U.S. patent number 3,747,087 [Application Number 05/156,762] was granted by the patent office on 1973-07-17 for digitally controlled computer animation generating system.
This patent grant is currently assigned to Computer Image corporation. Invention is credited to Lee Harrison, III, Francis J. Honey, Marshall M. Parker, Edwin J. Tajchman.
United States Patent |
3,747,087 |
Harrison, III , et
al. |
July 17, 1973 |
DIGITALLY CONTROLLED COMPUTER ANIMATION GENERATING SYSTEM
Abstract
This invention relates to a system for automatically producing
an animation sequence and includes an analog portion for generating
output signals representing one or more sections of a raster on
which images viewed by a video camera can be produced. Analog
inputs to the analog portion define the parameters of the raster
sections to effectively define the shape of each part of the viewed
image produced thereon. The analog inputs to the analog portion are
digitally controlled by signals from a digital computer portion
which establishes these digital control signals from information
fed to it from a director or a recording means.
Inventors: |
Harrison, III; Lee (Camarillo,
CA), Honey; Francis J. (Denver, CO), Tajchman; Edwin
J. (Denver, CO), Parker; Marshall M. (Lakewood, CO) |
Assignee: |
Computer Image corporation
(Denver, CO)
|
Family
ID: |
22560978 |
Appl.
No.: |
05/156,762 |
Filed: |
June 25, 1971 |
Current U.S.
Class: |
345/22; 352/52;
348/239; 348/586; 345/20; 348/32; 345/953; 345/473; 345/656;
315/367; 352/87 |
Current CPC
Class: |
G06G
7/06 (20130101); G06J 1/00 (20130101); Y10S
345/953 (20130101) |
Current International
Class: |
G06G
7/00 (20060101); G06J 1/00 (20060101); G06G
7/06 (20060101); G06f 003/14 () |
Field of
Search: |
;340/324A,324AD
;315/19,24 ;178/6.8,DIG.6,DIG.35 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Trafton; David L.
Claims
What is claimed is:
1. A method of producing an animation sequence of a subject from a
single still view of the subject comprising the steps of generating
video signals representing each part of the subject as selectively
divided into one or more parts; reproducing each of said parts of
the subject on a separate raster section generated from parameter
signals defining its size, shape, position, and structure; the
generation of each raster section being synchronized with the
generation of the video signals representing the part of the
subject produced thereon, establishing a series of digital signals
representing the parameters for each raster section over a given
time interval, which digital signals are selectively varying over
said time interval, and selectively varying the parameter signals
over said time interval in response to the digital signals to
produce changes in selected ones of the raster sections, thereby
producing corresponding changes in the parts of the subject
reproduced thereon.
2. The method of claim 1 further comprising the step of recording
the sequence.
3. The method of claim 1 further comprising the step of displaying
the parts of the image as reproduced on the raster sections.
4. The method of claim 1 further comprising the step of generating
video signals representing background information in
synchronization with the production of the animation sequence of
the subject.
5. A method of producing an animation sequence of a subject from a
single still view still the subject comprising the steps of
scanning each part of the subject as selectively divided into one
or more parts to produce video signals representing each part,
generating parameter input signals defining the size, shape,
position and structure of a raster section for each of said parts
of the subject, combining the parameter input signals to generate,
in synchronization with the generation of the video signals
representing each part of the subject, time varying coordinate
signals defining a raster section, modulating the intensity of the
electron beam of an electron beam device with the video signals
representing each part of the subject while simultaneously
directing the scan pattern of the electron beam with the coordinate
signals produced in synchronization therewith to reproduce each
part of the subject on a separate raster section, establishing a
series of digital signals defining the parameters for each raster
section over a given time interval, which digital signals are
selectively varying over said time interval, and selectively
varying the parameter input signals over said time interval in
response to the digital signals, thereby producing corresponding
changes in the scanning patterns of the electron beam, the raster
sections produced thereby and the parts of the subject produced
thereon.
6. The method of claim 5 wherein the position parameters include
parameters that define the angles of rotation of the raster
sections, and the method further comprising the step of varying
over time the angle of rotation parameters for selected ones of the
rasters to vary the angles of rotation of these rasters with
respect to reference axes.
7. The method of claim 5 wherein one of the scanning pattern
changes produces changes in the degree of bend in the raster lines
of selected ones of the raster sections.
8. The method of claim 5 including the step of generating in
synchronization with the generation of the video signals horizontal
and vertical sweep signals of selected slopes as part of the
parameter input signals.
9. The method of claim 5 further comprising the steps of generating
modulation signals, and selectively modulating the sweep signals
with the modulation signals.
10. The method of claim 5 further comprising the step of generating
video signals representing background information for the animation
sequence and combining the background information video signals
with the video signals representing each part of the subject to
produce an animation sequence of the subject with background.
11. The method of claim 10 further comprising the step of blanking
parts of the display positioned behind other parts of the
display.
12. A method of producing an animation sequence of an image, the
sequence divided into frames between initial and final frames, the
method comprising the steps of generating first sets of digital
signals representing scan pattern parameters for the initial frame
of the sequence, generating second sets of digital signals
representing scan pattern parameters for the final frame of the
sequence, generating further sets of digital signals using the
initial and final digital parameter signals as references
representing scan pattern parameters for each frame therebetween in
accordance with selected functions defining the patterns of
parameter change from frame to frame throughout the sequence, each
set of digital signals in each frame representing a distinct scan
pattern, converting the digital signals in each set of digital
signals to analog signals, generating from each first set of analog
signals a distinct scan pattern, the scan patterns from the first
sets representing the image of the initial frame, and generating a
distinct scan pattern from each further set of analog parameter
signals for each subsequent frame through the final frame of the
sequence to produce a series of images.
13. The method of claim 12 further comprising the step of
reproducing the parts of a subject divided into a selected number
of parts on the scan patterns in each frame of the sequence.
14. The method of claim 13 further comprising the steps of causing
the beam of a video camera to scan each part of the subject in
synchronization with the generation of a scan pattern to produce
video information representing each part of the subject, there
being as many scan patterns generated per frame as there are parts
of the subject, and producing an animated sequence of the subject
from the scan patterns and video signals.
15. The method of claim 14 further comprising the steps of
producing a recording of the sequence.
16. The method of claim 12 further comprising the steps of
recording the digital signals representing the scan pattern
parameters, and playing the digital recording back to produce the
analog signals.
17. The method of claim 12 including the steps of loading the
digital signals in each set sequentially into buffer units, and
transferring the digital signals in each set simultaneously from
the buffer units to generate a scan pattern.
18. A method of generating an image comprising the steps of
generating horizontal and vertical sweep signals representing
straight-line raster scans, establishing sets of digital data, the
digital data in each set defining parameters representing the size,
shape, position and structure of a raster section, converting the
digital data in each set to analog parameter signals, combining the
analog parameter signals in each set and the sweep signals in a
selected manner and sequence to produce time varying coordinate
signals representing a series of raster sections, generating
modulation signals, combining the modulation signals with selected
ones of the analog parameter signals, the digital signals defining
selected raster sections including signals defining the frequency
phase, amplitude, and waveform of the modulation signals.
19. The method of claim 18 further comprising the step of applying
the coordinate signals to the beam deflection inputs of a cathode
ray tube display device to produce a display of the image.
20. The method of claim 19 further comprising the steps of
generating video signals representing each part of a subject
divided into a selected number of parts in synchronization with the
generation of a raster section, and modulating the intensity of the
cathode ray tube beam with the video signals to produce a display
of the subject, whereby the size, shape and position of each part
of the displayed subject are determined by the size, shape and
position of the raster section on which it is reproduced.
21. The method of claim 20 further comprising the step of
compensating the beam intensity of the cathode ray tube for
variations in size of the image and velocity of the spot as the
beam scans.
22. The method of claim 18 further comprising the step of combining
a modulation signal of a selected frequency, phase, amplitude and
waveform with the vertical sweep signal to bend the lines of
selected raster sections.
23. The method of claim 18 further comprising the step of combining
a modulation signal of a selected frequency, phase, amplitude and
waveform with the horizontal sweep signal to vary the rate at which
the raster lines of particular raster sections are drawn.
24. The method of claim 18 further comprising the step of combining
a modulation signal of a selected frequency, phase, amplitude and
waveform with the analog parameter signals defining the depth of
particular raster sections.
25. The method of claim 18 further comprising the step of
synchronizing the generation of a modulation signal with the
generation of each line of a selected raster section.
26. The method of claim 18 wherein the analog parameter signals
include signals representing the sines and cosines of angles
through which selected raster sections are to be rotated with
respect to a reference axis, and further comprising the step of
combining combinations of other analog parameter signals with the
sine and cosine parameter signals to rotate the selected raster
sections.
27. The method of claim 26 wherein some of the combinations of
other analog parameter signals combined with the sine and cosine
parameter signals are produced by combining modulation signals with
selected ones of the analog parameter signals.
28. A computer animation system for generating an animation
sequence comprising a digital computer means, means for feeding
digital data to the digital computer means defining certain
parameters of an image for an initial frame of the sequence, means
for feeding digital data to the digital computer means defining
certain parameters of the image for a final frame of the sequence,
means associated with the digital computer means for automatically
calculating, upon command, the digital data defining certain
parameters of the image for each frame between initial and final
frames in accordance with selected patterns of parameter change
throughout the sequence, means for converting the digital data to
analog signals, and means for combining the analog signals to
produce signals representing the animation sequence.
29. The system of claim 28 including digital recording means, means
for recording the digital data defining the parameters of the image
for each frame of the sequence on the digital recording means, and
means to play back the digital data on the digital recording
means.
30. The system of claim 28 including a subject, means for producing
video signals representing the subject, and means responsive to the
video signals and signals representing the animation sequence to
produce an animation sequence of the subject.
31. The system of claim 30 including means responsive to the video
signals and signals representing the animation sequence to produce
a color
representation of the animation sequence of the subject. 33. The
system of claim 30 including means for blanking parts of the
subject positioned
other parts of the subject. 33. A system for generating time
varying coordinate signals for producing an animation sequence of
an image on a display device, film, or video tape, the system
comprising an analog network means having analog inputs and
outputs, means for generating horizontal and vertical sweep signals
representing straight line raster scans, circuit means associated
with the analog network means for generating time varying
coordinate signals representing a particular raster section at its
outputs from a given set of parameter signals and the sweep signals
at its inputs, the parameter signals defining the size, shape,
position and structure of the raster section, digital input means
for storing and transferring sets of digital data defining the
parameters of each raster section to be generated, means for
feeding digital data to the digital input means defining each
parameter of each raster section to be generated, means for feeding
the sets of digital data relating to the parameters of each raster
section to be generated from the digital input means in a
prescribed sequence, means for converting the sets of digital data
from the digital input means to sets of analog parameter signals,
means for feeding the sets of analog parameter signals and the
sweep signals to the appropriate inputs of the analog network means
to produce the time varying coordinate signals representing a
series of raster sections, means to generate video signals
representing each part of a subject divided into a selected number
of parts, the generation of the video signals for each part of the
subject being synchronized with the generation of the time varying
coordinate signals representing a raster section, and means
responsive to the video and coordinate signals for
producing a display of the animation sequence of the subject. 34.
The system of claim 33 wherein the sequence is comprised of frames,
the video signals representing each part of the subject being
generated during each
frame. 35. The system of claim 33 including means for generating
signals defining the red, blue and green color components for
colors assigned to each part of the subject, and means responsive
to the video signals, coordinate signals, and color component
signals to produce a color
representation of the animated subject. 36. The system of claim
33
including means defining the number of lines in each raster
section. 37. The system of claim 33 including means for rotating
each raster
section about a selected axis of rotation. 38. The system of claim
37 wherein the analog parameter input signals defining each raster
section include signals defining the size and axis of rotation of
the raster section, and including means for automatically
compensating the axis of
rotation for variations in size of the raster section. 39. The
system of claim 38 wherein the size parameter signals are
multiplied by the axis of
rotation parameter signals. 40. The system of claim 33 including
means for feeding the digital data within each set of digital data
to the conversion means in a prescribed sequence, and means to
simultaneously transfer the digital data in each set of digital
data to the inputs of the analog
network means. 41. A system for generating an animation sequence of
an image composed of one or more raster sections, each raster
section being defined in terms of size, shape, position and
structure by analog parameter signals, the sequence divided into
frames between initial and final frames, the system comprising
analog network means having coordinate outputs and parameter
inputs, means associated with the analog network means for
generating time varying coordinate signals at its outputs
representing a raster section of a size, shape, position and
structure defined from a set of analog parameter signals at its
input, digital computer means, means for feeding digital data to
the digital computer means defining the parameters of the raster
sections for the initial frame of the sequence, means for feeding
digital data to the digital computer means defining the parameters
of the raster sections for the final frame of the sequence, means
associated with the digital computer means for establishing certain
parameters of the raster sections between initial and final frames,
means for generating as many sets of digital signals as there are
raster sections composing the image for each frame, each set of
digital signals defining the parameters of a raster section, means
for loading the digital signals in each set in timed sequence into
a series of interface units beginning with the set defining the
first raster section to be generated in the first frame and
continuing in timed sequence through the set defining the last
raster section to be generated in the last frame, means for
simultaneously initiating the transfer of the digital signals from
the interface units after the last of the series of interface units
is loaded with one set of signals, means for loading the digital
signals of the next set into the interface units as soon as the
prior set is transferred therefrom, means for converting the
digital signals from the interface units to analog signals, and
means for applying the analog signals to the inputs of the analog
network means to produce time varying coordinate signals at its
outputs sequentially representing the raster sections of the image
for each frame throughout the sequence.
Description
CROSS REFERENCES TO COPENDING RELATED APPLICATIONS
This application relates to the disclosures of application Ser. No.
95,096 filed Dec. 4, 1970, now U.S. Pat. No. 3,710,011, and
application Ser. No. 72,642, filed Sept. 16, 1970, now U.S. Pat.
No. 3,689,917.
SUMMARY OF THE INVENTION
The invention of this application produces animation sequences of
scenes in a way different from any other system, to create a new
and novel computer animation system that provides greatly increased
figure animation capability.
The system basically includes an analog portion for generating
output signals representing one or more sections of a raster on
which images viewed by a video camera can be produced. Analog
inputs to the analog portion define the structure, size, shape,
location, orientation and other parameters of the raster section to
effectively define the shape of each part of the viewed image
produced thereon. By varying the analog inputs, the raster section
parameters can be made to vary, thus imparting motion to the image.
In this system the values and variations in values of the analog
inputs are controlled by digital signals from a digital computer
which establishes these digital control signals from information
fed to it from a director.
More specifically, the analog computer portion generates X and Y
coordinate signals representing each section of an animated image
for each frame of an animated sequence, each section of the image
comprising a raster section. Sweep generators within the analog
portion generate the basic horizontal and vertical sweep signals
which are combined with, or modulated by, other input signals to
define the structure, shape, size, position and other parameters of
each raster section for each sequence frame. The X and Y coordinate
signals at the output of the analog portion can be applied to a
cathode ray tube to produce a display of the animated sequence or
can be used to record the sequence on video tape or film.
The input signals to the analog portion define, for each raster
section, parameters such as X and Y position, X and Y size,
horizontal and vertical axes of rotation which determine the radius
of rotation of each raster section, section depth, cosine and sine
of the angle of rotation, intensity, and horizontal, vertical and
depth modulation. Other parameter inputs define overall X and Y
position and depth for the entire image. All of these parameter
input signals act in conjunction with the sweep generators to
ultimately produce the X and Y coordinate output signals from the
analog portion for use in producing an animation sequence. By
varying these input signals, each raster section can be made to
vary in height or width, move anywhere in relationship to any other
raster sections, rotate about any point located inside or outside
the raster section, and can be modulated with the variety of
modulation signals to produce bending or distortion of the raster
section, which bending or distortion can be made to vary by varying
modulation signal parameters such as frequency, phase and
amplitude.
The parameter signals of the analog portion and the modulation
signal parameters are established for each section of the image and
for each frame of the sequence by a digital computer portion which
automatically calculates these parameters from information it
receives at its input from a director. Parameter data for each
raster section for initial and final frames of a sequence of a
selected number of frames are selected on the director, which
information is fed to the digital computer. The digital computer is
programmed to automatically calculate, upon command, the parameter
data for each section and for each frame between initial and final
frames in accordance with a selected fairing function and to store
this information in a digital memory such as magnetic tape or disc.
Depending on the fairing function selected, these digital
computations may be linear or based on some other mathematical
function to define the patterns of parameter change throughout the
sequence. For example, in this way an arm of a figure can be made
to move at a constant rate from a first to a second position, or at
a varying rate depending on the fairing function selected. The
digital information recorded on the magnetic tape or disc can then
be played back through the digital computer to the analog portion
to produce the animated sequence.
Where a figure is displayed on the animated raster sections a video
camera is trained to scan the individual parts of the figure to be
animated. Timing pulses are generated to time the scan of the video
camera in synchronization with the production of the X and Y
coordinate output signals from the analog portion to reproduce each
part of the scanned figure on a raster section as defined by the X
and Y coordinate output signals. The result is that the video
signals from the video camera determine the detail surface
characteristics and shape of each part of the image as displayed on
a raster section, while the analog portion of the computer defines
the structure, shape, size, position and other parameters of each
raster section as determined by the values of its parameter inputs.
Digital signals from the digital computer vary the parameter inputs
in a controlled manner between initial and final frames to animate
the raster sections and hence the parts of the figure produced
thereon to create the animation sequence.
With this system the editing is actually done by the digital
computer and not after the scenes are recorded on video tape or
film. By dividing a sequence to be filmed into segments or scenes
having initial and final frames, the information for creating each
frame of the entire sequence can be recorded on digital magnetic
tape as the scenes are produced, which information can then be
played back through the system for ultimate display or recording of
the animation sequence on film or video tape. In this way, a
sequence of any length can be produced without the need to edit the
film or video tape.
Means are also provided for adding background information to the
sequence and for varying the background and image foreground
information by switching artwork video inputs during the sequence.
The system further includes means for producing the entire sequence
in colors that can be selectively varied.
From the foregoing, it is apparent that this system allows an
artist to produce animated sequences in far less time than would be
possible using conventional techniques (requiring 24 separate
drawings for each second of animation) and yet provides him with
wide control for producing many different types of animation. The
result is that the artist animates with the computer by operating
the director controls, giving his full attention to creativity and
results rather than the tedium of repetition.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a general block diagram of the system of this invention
for generating an animation sequence;
FIG. 2 is a block diagram of a network for producing a color
display or video tape of an animation sequence generated by the
network of FIG. 1;
FIG. 3 is a block diagram of a network for producing a color
recording on film of an animation sequence generated by the network
of FIG. 1;
FIG. 4 and 4A combined are a schematic drawing of the analog
computer portion of the system;
FIG. 5 is a block diagram of the control network of the system;
FIG. 6 is a block diagram of the frequency synthesizer of the
system;
FIG. 7 is a block diagram of the function generator of the system;
and
FIGS. 8, 9, 10, 11 and 12 are illustrations used in explaining the
operation of the system.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT
Before describing the system components in detail, the system will
be generally described by referring to the block diagrams of FIGS.
1, 2 and 3. An input interface unit 20, also called a director,
generates analog and digital signals defining each parameter of
each raster section for a given frame of the sequence to be
generated. The values of these signals are set with analog
controls, such as for example, potentiometers, and digital
parameter or channel select controls, such as for example,
multiposition switches, which determine the parameter or parameters
being defined at a given instance by the analog control signals.
The analog signals from the director 20 are converted to digital
signals and fed to a digital computer 22, such as a Honeywell 316
or equivalent, which is programmed to store on appropriate command
the digital information relating to each parameter of the given
frame and to feed this information in a prescribed manner to an
interface network 24 containing a plurality of interface units.
Some of these units convert the digital parameter data from the
digital computer 22 to analog parameter signals and transfer these
signals to parameter inputs of an analog computer portion 26.
Digital data from other interface units of the interface network 24
is fed to a frequency synthesizer 32 to define the frequencies of
modulation signals used for producing certain animation effects.
Digital data from still other interface units of the interface
network 24 is fed to a function generator 34 for defining the
phase, wave form, amplitude, and synchronization mode of the
modulation signals, which signals are fed from the output of the
function generator 34 to modulation parameter inputs of the analog
computer portion 26. From these inputs and those from the interface
units of the interface network 24, the analog computer portion 26
generates signals at its output defining raster sections. In this
way such parameters as the structure, shape, size and position of
each raster section generated at the output of the analog portion
26 are defined by the control settings of the director 20.
The digital computer 22 is also programmed upon receipt of
parameter information from the director 20 defining initial and
final frames of an animation sequence of a given number of frames
to automatically calculate the parameter information defining each
frame therebetween in accordance with an appropriate fairing
function selector on the director, which function defines the
pattern of variation for each parameter throughout the sequence,
and to record the digital parameter information defining the entire
sequence on a digital recording device such as a magnetic tape unit
36 or magnetic disc unit 38. Upon appropriate command from the
director 20, the digital information stored on the digital tape 36
or disc 38 is played back through the digital computer 22,
interface network 24, and analog computer portion 26, to produce
signals at the output of the analog portion 26 representing the
entire animation sequence.
The system also includes a plurality of video cameras such as 40,
41 and 42, each of which can be made to scan an art-work subject
for display on the raster sections generated by the analog portion
26. The artwork subjects could be from most any source such as a
slide projector 43, or light boxes 44 and 45, on which the artwork
is mounted. The video information from each of the cameras 40
through 42 is sent to a switcher unit 52 which is controlled by
signals from the outputs of still other interface units of the
interface network 24 to switch the video of a selected one of the
cameras 40 through 42 to the input of a gray level encoder 54. The
encoder 54 is fully described in copending U.S. patent application
Ser. No. 95,096, filed Dec. 4, 1970 now Pat. No. 3,710,011,
entitled A System For Automatically Producing A Color Display of A
Scene From A Black And White Representation Of The Scene. For the
purposes here, it is sufficient to know that the encoder 54
produces video signals at its output representing the artwork in
discrete shades of gray, which signals are fed to an overlap
network 56 together with the output signals from the analog portion
26. The overlap network 56 may be of the type disclosed in FIG. 8
of U.S. Pat. No. 3,364,382 for blanking portions of the generated
image appearing behind other portions of the image. To accomplish
this, an output signal from the overlap network 56 is fed to a
video gate 58 to gate the video signal from the output of the gray
level encoder 54, through the gate 58, to an output conductor 60
only when image information is generated over an area not
previously covered with other image information. Hence, the output
conductor 60 carries a video signal representing the artwork in
discrete shades of gray and which has been compensated for overlap
prevention. This video signal can be used to reproduce the various
parts of the artwork on the raster sections generated by the analog
computer portion 26.
The analog computer portion 26 generates horizontal and vertical
reset pulses from signals received by it from the frequency
synthesizer 32. These horizontal and vertical reset pulses are fed
from the analog computer portion 26 to the digital computer portion
22, as shown by conductors 62, and to a camera control network 64,
as shown by conductors 66, to synchronize the generation of the
coordinate output signals from the analog portion 26 defining the
raster sections with the generation of the video signals on the
conductor 60 representing the artwork.
The coordinate output signals from the analog portion 26 and video
signals on the conductor 60 may be typically used to produce either
a black and white or color display, video tape, or film of the
animation sequence with the networks of FIGS. 2 and 3. Referring to
FIG. 2, the output signals from the analog portion 26 and video
signals on the conductor 60 are fed into a color network 67,
together with signals from still other interface units of the
interface network 24 defining the red, blue and green color
components for each discrete gray shade. The color network 67 may
be of any one of the embodiments fully disclosed in the
above-reference application Ser. No. 95,096 for assigning colors to
each gray shade. The output from the network 67 may be used
directly to produce a color display or video tape of the animation
sequence, or fed to a video effects unit 68 and combined with
signals representing background information in TV format, such as
from a color video camera 69 photographing background artwork 70, a
conventional film chain 71, or a video tape recorder 72, any one of
which may be used to supply background information for the
sequence.
The output from the video effects network 68 is fed to a color
monitor 73 for producing a color display of the animation sequence,
directly to a video tape recorder 74 to produce a video tape of the
sequence, or to a microwave link 75 for transmission to a video
tape recorder 76.
In FIG. 3, there is shown a network for producing a color film of
the animation sequence. The video signal on the conductor 60 and
the output signals from the interface units of the interface
network 24 defining the red, blue and green color components of the
color to be assigned to each gray shade, are fed to an RGB color
color encoder 77, such as the type shown in FIG. 6 of the
above-referenced application Ser. No. 95,096. The encoder 77
generates a video signal at an output 78 representing the red color
component of each assigned color which is fed to an X-Y monitor 79,
a video signal at an output 80 representing the blue color
component of each assigned color which is fed to an X-Y monitor 81,
and a video signal at an output 82 representing the green color
component of each assigned color which is fed to an X-Y monitor 83.
The coordinate output signals from the analog portion 26 are also
fed to each of the X-Y monitors 79, 81 and 83, the X-Y monitor 79
producing a black and white display defining the red color
components of the sequence filmed by a camera 84 on red encoded
black and white film, X-Y monitor 81 producing a black and white
display defining the blue color components of the sequence filmed
by a camera 85 on blue encoded black and white film, and the X-Y
monitor 83 producing a black and white display defining the green
color components of the sequence filmed by a camera 86 on green
encoded black and white film. The red, blue and green encoded films
are then processed in the laboratory by known techniques to produce
a composite color film of the animation sequence.
As a variation of this technique, the monitors 79, 81 and 83 could
be equipped with high intensity tubes with red, blue and green
phosphors, respectively, and the images produced thereon optically
combined and photographed on color film.
ANALOG COMPUTER PORTION
The analog computer portion 26 will be described in more detail by
referring to the network of FIGS. 4 and 4A. The analog portion 26
includes summation amplifiers 90 and 91. Output conductors 92 and
93, respectively, from the summation amplifiers 90 and 91 carry X
and Y coordinate signals for generating a raster section the
parameters of which are defined by input signals to the analog
portion 26. By changing the values of these input signals, the
values of the X and Y coordinate signals at the outputs 92 and 93
are changed, thereby changing the parameters of the raster section
generated thereby.
Remembering that the coordinate output signals 92 and 93 produce a
raster section the parameters of which are defined by the values of
the input signals to the analog portion 26, it can best be
understood how these coordinate signals are generated and what
these raster parameters are by beginning at the inputs of the
analog portion 26.
The analog portion 26 has a plurality of inputs each of which has
an analog parameter signal thereon for defining the shape, size,
position and structure for a given raster section represented by
the X and Y coordinate outputs 92 and 93. The signal at an input 95
defines the overall X position of the entire image comprised of a
selected number of raster sections; the signal at an input 96
defines the X position of a given section of the image relative to
the other sections of the image; the signal at an input 97 defines
the horizontal size or length of raster lines of the given raster
section; the signal at an input 98 defines the horizontal axis of
rotation of the given raster section; the signal at an input 99
defines the vertical axis of rotation of the given raster section;
the signal at an input 100 defines the vertical size or the spacing
between raster lines of the given raster section; the signal at an
input 101 defines the Y position of the given raster section
relative to the other sections of an image; the signal at an input
102 defines the overall Y position of the entire image; the signal
at an input 103 defines the depth or overall size of the given
raster section; the signal at an input 104 defines the overall
depth or overall size of the entire image; signals at inputs 105
and 106 define the cosine and sine, respectively, of an angle R,
where R is the angle of rotation of the given raster section with
respect to a reference axis; and inputs 107, 108 and 109 carry
modulation signals from the function generator 34 to be described,
for producing depth, vertical and horizontal modulations of the
given raster section. The inputs 95 through 106 are from interface
units of the interface network 24, and the inputs 107 through 109
from the function generator 34.
A 1.2 megahertz signal generated by the frequency synthesizer 32,
to be described, is fed to an input 110 and through a conductor 111
to a sync generator 112. From the 1.2 megahertz signal, the sync
generator 112 produces a 60 hertz signal for comparison with the 60
hertz line frequency and creates therefrom a voltage control
oscillator (VCO) control signal at an output 113 which is fed back
to the frequency synthesizer 32. The VCO signal adjusts the
frequency of the 1.2 megahertz signal to insure that the 60 hertz
signal generated by the sync generator 112 is locked to the line
frequency. The generator 112 generates at one of its outputs 114 a
horizontal reset signal of a frequency of 28.35 kilohertz, and at
another output 115 a vertical reset signal of a frequency of 60
hertz. As will be seen, these horizontal and vertical reset signals
are used throughout the system to synchronize various timing
operations.
The horizontal reset signal on the conductor 114 is fed through a
conductor 116 and a conductor 117 to the reset input of an
integrator 118. Another input conductor 119 to the integrator 118
is connected from the input 97 defining the horizontal size of a
particular raster section. Therefore, after each horizontal reset
pulse the integrator 118 operates as a horizontal ramp generator to
draw a line of the raster section of a length determined by the
magnitude of the signal at the input 97. The output of the
integrator 118 is fed through a conductor 120 to one input of a
summation amplifier 121. The summation amplifier 121 has another
input conductor 122 connected to the input 109 carrying the
horizontal modulation signal from the function generator 34.
Another input conductor 123 to the summation amplifier 121 is
connected from the output of a multiplier 124 having one input
connected by a conductor 125 to the horizontal size input 97, and
having another input conductor 126 connected to the input 98
defining the horizontal axis of rotation of the section. Therefore,
the purpose of the multiplier 124 is to insure that where there is
an increase in the horizontal size of the raster section, there is
automatically a corresponding change in the horizontal axis of
rotation of that section to insure that the section rotates about
the same relative point. The output of the summation amplifier 121,
representing the sum of the horizontal ramp function, the
horizontal modulation signal, and the product of the signals
representing the horizontal axis of rotation and the horizontal
size of the raster section is fed through a conductor 130 and a
conductor 134 to one input of a multiplier 136.
The vertical reset signal at the output 115 from the sync generator
112 is fed through a conductor 140 and a conductor 142 to the reset
input of an integrator 144. The integrator 144 has an input
conductor 146 connected from the analog computer input 100 defining
the vertical size of each raster section so that each time after
the integrator 144 receives a vertical reset pulse, it generates a
vertical ramp function defining the height of the raster section
(the distance between the raster lines) in accordance with the
magnitude of the signal at the input 100. The output of the
integrator 144 is fed through a conductor 150 to one input of a
summation amplifier 152. Another input conductor 154 to the
summation amplifier 152 is connected from the input 108 to the
analog portion carrying the vertical modulation signal from the
function generator 34. Another input conductor 156 to the summation
amplifier 152 is connected from the output of a multiplier 158
having one input connected by a conductor 160 to the input 99 of
the analog portion carrying the signal defining the vertical axis
of rotation of the raster section, and another input conductor 162
connected from the vertical size input 100. The multiplier 158
performs the same function with respect to compensating for changes
in vertical size as the multiplier 124 does for compensating for
changes in horizontal size. That is, where there is a change in the
vertical size of the raster section, the multiplier 158 insures
that there is automatically a corresponding change in the vertical
axis of rotation so that the point of rotation remains in the same
relative position. The output from the summation amplifier 152
representing the sum of the vertical ramp signal, the vertical
modulation signal, and the product of the signals defining the
vertical axis of rotation and vertical size of the raster section
is fed through a conductor 165 and a conductor 169 to one input of
a multiplier 171.
To provide a wide variety of animation capability, this system
includes means for rotating each raster section about a point
defined by the horizontal and vertical axes inputs 98 and 99 and
through an angle, which will be called R, the cosine and sine of
which are defined by voltages at the inputs 105 and 106,
respectively, to the analog portion 26. The system further includes
means for rotating any raster distortion with the raster. To
illustrate the importance of these rotation capabilities, consider
the problem of producing an animation sequence of a walking figure.
As the figure moves, the legs must bend at the knees and rotate at
the hips, and the arms must bend at the elbows and rotate at the
shoulders. Taking one of the arms as an example, as the raster
section on which the arm is produced rotates causing rotation of
the arm about the shoulder, the raster distortion pattern creating
the bend at the elbow, which bend is produced by a selected
vertical modulation signal from the function generator 34, must
also rotate or else an unnatural or undesirable distortion of the
arm will result. For this reason, rotation is imparted to the
raster section after the modulation signals are summed with the
horizontal and vertical ramp signals. Hence, the signal at the
input 105 representing the cosine of R is fed through a conductor
180 and a conductor 181 to a second input of the multiplier 136,
and through a conductor 183 to a second input of the multiplier
171. The signal at the input 106 representing the sine of R is fed
through a conductor 185 and a conductor 187 to one input of a
multiplier 189, the other input of which is connected by conductor
191 to the output of the summation amplifier 152. The signal on the
conductor 185 representing the sine of R is also fed through a
conductor 195 to one input of a multiplier 197 having another input
connected by a conductor 200 to the output of the summation
amplifier 121. The output from the multiplier 136 representing the
product of the output from the summation amplifier 121 and the
cosine of R is fed through a conductor 205 to one input of a
summation amplifier 207. The output from the multiplier 189
representing the product of the output from the summation amplifier
152 and the sine of R is fed through a conductor 209, an inverter
211 and a conductor 213 to a second input of the summation
amplifier 207. The summation amplifier 207 has a third input
conductor 215 connected from the input 96 of the analog portion 26
carrying the signal defining the X position of the section. The
output from the multiplier 197 representing the product of the
output from the summation amplifier 121 and the sine of R is fed
through a conductor 219 to one input of a summation amplifier 221.
The output from the multiplier 171 representing the product of the
output from the summation amplifier 152 and the cosine of R is fed
through a conductor 223 to a second input of the summation
amplifier 221. The summation amplifier 221 has a third input
conductor 225 connected from the input 101 of the analog portion 26
carrying a signal defining the Y position of the raster
section.
A summation amplifier 230 has one input connected by a conductor
231 to the input 103 of the analog portion carrying the signal
defining the depth of the raster section, another input connected
by a conductor 232 to the input 107 of the analog portion carrying
the depth modulation signal from the function generator 34, and
another input connected by a conductor 233 to the input 104 of the
analog portion carrying the signal defining the overall depth of
the entire image. The output from the summation amplifier 230
representing the sum of these depth signals is fed through a
conductor 235, a conductor 236, and a conductor 237 to one input of
a multiplier 238. The output from the summation amplifier 207 is
fed through a conductor 240 to a second input of the multiplier
238. The output from the summation amplifier 230 is also fed
through the conductors 235 and 236 and through a conductor 242 to
one input of a multiplier 244, the other input of which is
connected by a conductor 246 to the output of the summation
amplifier 221. The output from the multiplier 238 representing the
product of the signals from the summation amplifiers 207 and 230 is
fed through a conductor 248 to one input of the summation amplifier
90. Another input of the summation amplifier 90 is connected by a
conductor 250 to the input 95 of the analog portion 26 carrying the
signal defining the overall X position of the image. The output
from the multiplier 244 representing the product of the signals
from the summation amplifiers 221 and 230 is fed through a
conductor 252 to one input of the summation amplifier 91. Another
input of the summation amplifier 91 is connected by a conductor 254
to the input 102 of the analog portion 26 carrying the signal
representing the overall Y position of the image. Hence, the output
from the summation amplifier 90 represents the X coordinate signal
for the raster section, and the output of the summation amplifier
91 represents the Y coordinate signal for the raster section.
From the above description, it is apparent that the analog portion
26, given a set of fixed input parameter signals, generates a
raster section of a particular size, shape, structure, and position
as defined by these input signals. If the input parameter signals
remain constant over time, identical raster sections will be
generated repeatedly. If, on the other hand, the input parameter
signals are changed in a prescribed manner over a prescribed time
interval, a plurality of raster sections, each shaped, sized,
structured and positioned differently from the others, are
generated. Furthermore, by changing the input parameter signals
defining each raster section at prescribed increments and at a
prescribed frequency, motion can be imparted to the rasters and
hence the image, to produce an animation sequence. The control of
the input parameter signals to the analog portion 26 to produce and
animate the different raster sections is accomplished with the
control network of FIG. 5.
CONTROL NETWORK.
In generating an animation sequence, the control network operates
in basically three modes: a frame reference mode, a record mode,
and a playback mode.
In the frame reference mode the digital computer 22 receives
digital parameter information from the director 20 for establishing
initial and final frames for the sequence. The director 20 has an
analog input portion 270 (which might include, for example, a
plurality of potentiometers or the like) for generating analog
signals which might be used to define any raster parameter, and a
parameter select input 272 (which might include multiposition
switches) for selecting the parameter to be defined by the analog
signal from the analog input 270. The analog input signals from the
analog input 270 selected for particular ones of these parameters
are fed through suitable conductors 274 to one input of a
multiplexer 275 having another input connected by conductor 276 to
an output from the digital computer 22 which carries signals in
accordance with its program to gate the analog information from the
analog input 270 in a prescribed sequence through conductors 277 to
the input of an analog to digital converter 278. The digital output
signals from the converter 278 are fed through conductors 279 to an
input of the digital computer 22.
The computer 22 is programmed to store the information received
from the analog input 270 and to interrogate through appropriate
conductors 282 the parameter select unit 272 to determine the
parameter to which each piece of stored information pertains.
Having made this determination, the parameter information is
transferred to an appropriate storage location within the computer
22. By manipulating the analog input 270 and parameter select 272
controls, digital signals are eventually stored in the appropriate
memory locations of the digital computer 22 representing each
parameter of each raster section of the image for the initial frame
of the sequence. Having stored the initial frame information, the
same procedure is followed for establishing the digital parameter
information for the last frame of the sequence.
Having established the initial and final frame parameters for the
sequence the digital computer 22 can now be placed in the record
mode. In this mode the digital computer 22 is programmed to
calculate, upon command from the director 20, the digital parameter
information defining each raster section of each frame between
initial and final frames, and to record this information on the
digital recording device such as magnetic tape 36 of disc 38. These
calculations are made in accordance with a selected one of several
mathematical functions called fairing functions which define the
rate of change of each parameter from frame to frame throughout the
sequence. For example, if a linear fairing function is selected,
the rate of parameter change from frame to frame is constant, while
other fairing functions produce varying change rates. The computer
22 is programmed to make its calculations in accordance with any
one of the several fairing functions, a particular function
selected by command signal from the director 20.
With the digital parameter information defining each raster section
of each frame of the sequence recorded on the digital recording
device, the control network can be placed in its playback mode to
play the recorded digital parameter information back to the digital
computer 22 where it is stored in a prescribed sequence in various
memory locations.
In this manner digital parameter information is fed to and stored
in the digital computer 22 for transfer to other networks of the
system such as the analog portion 26, frequency synthesizer 32, and
function generator 34, to generate the sequence. The manner in
which this transfer is accomplished is the time regardless of its
source (whether from the director 20 or digital magnetic recording
devices 36 or 38) and will not be explained.
As parameter information from one of the input sources is stored at
some memory location within the computer 22, the computer 22 is
programmed to transmit this information sequentially at high speed,
and in a specified order to interface units within the interface
network 24. In this described embodiment of the invention there are
basically four types 285, 286, 287 and 288 of these interface
units. There may be any number of each type depending on the number
of parameters to be defined. For example, in this embodiment there
are nine units of the type 285, two units of the type 286, 31 units
of the type 287, and one unit of the type 288 for a total of 43
interface units, each to affect a different parameter as each
raster section of an image frame is drawn. There are, therefore, at
least as many interface units as there are parameters to be defined
for each raster section generated.
The information stored in the digital computer 22 defining each
parameter is fed in an order determined by the digital computer
program to each of the interface units. Hence, for example, the
information defining a first parameter of a given raster section is
fed through conductors 290, 291 and 292 to an interface unit of the
type 285; conductor 290, 291 and 293 to an interface unit of the
type 286; conductors 290, 294 and 295 to an interface unit of the
type 287; and conductors 290, 294 and 296 to an interface unit of
the type 288; and so on for the information defining the second and
succeeding parameters until all of the parameter information
defining a particular raster section of the frame is fed to the
inputs of each interface unit.
As the information defining the first parameter is fed to each
interface unit at high speed, a signal is sent from the digital
computer 22 through a conductor 300 to a channel address counter
302 which has a separate output connected to a gate input of each
interface unit. To illustrate, there is an output conductor 305
connected to a gate input of the interface unit of the type 285, an
output conductor 306 connected to a gate input of the interface
unit of the type 286, an output conductor 307 connected to a gate
input of the interface unit of the type 287, and an output
conductor 308 connected to a gate input of the interface unit of
the type 288.
In this embodiment with 43 interface units, the counter 302 would
have 43 such output conductors each connected to a gate input of an
interface unit. Each time the digital computer 22 feeds information
defining a parameter for a particular raster section to each
interface unit it sends a signal through the conductor 300 to
activate an appropriate one of the outputs of the counter 302 which
in turn gates the information which is present at the inputs of all
the interface units to the appropriate one of these units. The
digital computer 22 is programmed to feed the digital parameter
information in the proper sequence so it is gated to the
appropriate interface unit to effect the appropriate parameter
input to the system.
When the last output conductor, which for purposes of illustration
might be the conductor 308, of the counter 302 is activated to gate
digital parameter information to the last interface unit, all the
units are loaded and the high speed transfer of information from
the digital computer 22 relating to the next raster section to be
generated must be stopped. Hence, the gating signal on the last
output conductor 308 of the counter 302 is also fed through a
conductor 309 to an input of the digital computer 22 to stop the
high speed transfer. As will be seen, the high speed transfer of
information from the digital computer 22 will be started again to
reload the interface units with information by the start of a
vertical reset or a section change pulse defining the next raster
section.
Each of the types of interface units 285 through 288 is designed
differently to perform a different interface function and for
interface with a different part of the system. The unit type 285 is
used for interface with the frequency synthesizer 32 and function
generator 34 for defining the frequency, phase, waveform, and
synchronization mode parameters of the modulation oscillators for
use in creating vertical, horizontal and depth modulation. In this
embodiment, two such units are required to define frequency, and
one for phase, waveform and synchronization mode. With vertical,
horizontal, and depth modulation, nine such units are used. Each
unit type 285 includes a shift register 310 having one input,
connected by conductors 290, 291, and 292 to the output of the
digital computer 22 for receiving the digital parameter
information, an input connected by the conductor 305 to an output
of the channel address counter 302 for gating the appropriate
digital parameter information into the shift register 310, and an
input connected by a conductor 311 and a conductor 312 to the
output of a clock control 313. The clock control 313 has an input
315 connected to the output of an OR gate to be described. When the
clock control 313 receives a signal at its input 315, it transmits
a series of pulses through the conductors 312 and 311 to the input
of the shift register 310 to feed the digital parameter information
in the shift register 310 serially through an output conductor 316
to the frequency synthesizer 32 or function generator 34. The clock
pulses from the output of the clock control 313 are also fed
through a conductor 317 to the frequency synthesizer 32 or function
generator 34.
Each interface unit of the type 286 includes a first buffer 320 and
a second buffer 321, the input of which is connected to the output
of the buffer 320. The buffer 320 has one input connected by the
conductors 290, 291 and 293 to the output of the digital computer
22 for receiving the digital parameter information, and an input
connected by the conductor 306 to an output of the channel address
counter 302 for gating the appropriate digital parameter
information into the first buffer 320. The second buffer 321 has an
input 322 which, like the input 315 of the clock control 313, is
connected to the output of the OR gate. On appropriate signal at
the input 322, the digital parameter information in the first
buffer 320 is transferred to the second buffer 321 and through an
output conductor 323 to provide digital control signals available
for such operations as section blanking and video switching. In
this embodiment, two such unit types 286 are used, although, of
course, the number depends on the number of digital control signals
required for various contolling operations.
An interface unit of the type 287 is used to interface with each of
the parameter inputs 95 through 106 of the analog portion 26, and
the function generator 34 to define the amplitudes of the
modulation signals. Since there are vertical, horizontal, and depth
modulations, three such units are required for this purpose. Units
of this type are also used to interface with the color network 67
or RGB color encoder 77 of FIGS. 2 and 3, for defining the colors
of each frame of the image. For example, where each frame has five
different colors (five discrete shades of gray, a color for each
shade), and since each color has a red, blue and green color
component, 15 such units are required. A unit of this type is also
used to interface with an intensity compensation network, to be
described.
Each interface unit of the type 287 includes a first buffer 324 and
a second buffer 325, the input of which is connected to the output
of the first buffer 324. The first buffer 324 has an input
connected by the conductors 290, 294 and 295 to the output of the
digital computer 22 for receiving the digital parameter
information. The buffer 324 also has an input connected by the
conductor 307 to an output of the channel address counter 302 to
gate the appropriate digital parameter information into the buffer
324. For example, this information might define one of the color
parameters, or an amplitude parameter for a modulation oscillator,
or one of the input parameters 95 through 106 to the analog portion
26. The buffer 325 has an input 326 which, like the inputs 315 and
322 to the units 285 and 286, is connected to the output of the OR
gate. Upon receiving an appropriate signal at the input 326, the
digital information in the buffer 324 is transferred to the buffer
325 and fed through the conductors 327 to the input of a digital to
analog converter 328 which converts the digital information to an
analog signal for transmission through its output conductor 329 to
the appropriate parameter input of the system.
The interface unit type 288 has the dual function of defining the
number of raster lines in each raster section and timing the
transfer of parameter information from the digital computer 22 to
the parameter inputs of the analog portion 26 and other parameter
inputs of the system. In this described embodiment, there is only
one interface unit of the type 288 required in the system. It
includes a buffer 330 and a section length counter 331, an input of
which is connected to the output of the buffer 330. The buffer 330
has one input connected by conductors 290, 294 and 296 to the
output of the digital computer for receiving the digital parameter
information, and an input connected by the conductor 308 to the
appropriate output of the channel address counter 302 for gating
into the buffer 330 the digital parameter information from the
digital computer 22 which defines the number of lines in the
section being generated. The section length counter 331 has an
input conductor 332 which is connected by conductors 333, 334, 116
and 114 to the horizontal reset output of the sync generator 112
(FIG. 4). The section length counter 331 continuously counts the
horizontal reset pulses on its input conductor 332 and upon
reaching a prescribed count, generates an overflow or section
change signal at an output conductor 335. How long the counter 331
must count to generate the overflow signal depends on the digital
information fed to it from its input buffer 330. The length of the
count by the counter 331 defines the number of lines in the section
being generated.
When the counter 331 stops counting and generates the section
change signal at its output, this signal is fed through the
conductor 335 and a conductor 337 to an input of a blanking
generator 338 (FIG. 4). The blanking generator 338 has another
input connected by a conductor 340, a conductor 341 and the
conductors 140 and 115 to the vertical reset output of the sync
generator 112, and another input connected by a conductor 342 and
in the conductors 334, 116 and 114 to the horizontal reset output
of the sync generator 112. Upon receiving a section change signal
from the counter 331, the blanking generator 338 generates a signal
at its output which is fed through a conductor 345 for use in
blanking the beam of a monitor used for displaying the image or a
scan converter used in producing the image in TV format. The
blanking generator 338 is set to generate the blanking signal for a
period of time equivalent to approximately two horizontal raster
lines, although this period is adjustable. The blanking generator
338 generates another signal at an output which is fed through a
conductor 346 for use in blanking the beam of the artwork scanning
camera, such as the camera 40, 41 or 42, a monitor used for
displaying the image, or a scan converter used in producing the
image in TV format, between each scan cycle and raster line. For
example, where as is customary there are two interlacing scan
cycles or fields per frame, the blanking signal on the conductor
346 blanks the beam between each field and raster line. This, of
course, is to insure that the beam is turned off during flyback
from the end of one scan or line to the beginning of the next.
The section change signal on the output conductor 335 of the
section length counter 331 is also fed through a conductor 370 to
one input of an OR gate 371 which has another input connected by a
conductor 372, a conductor 373, and the conductors 341, 140 and 115
to the vertical reset output of the sync generator 112, (FIG. 4).
The output of the OR gate 371 representing either the vertical
reset or section change signals is fed through a conductor 374 to a
preset input 375 of the section length counter 331 to preset the
counter at the end of each raster section and frame, or at the end
of each raster section and field if there are two fields per frame,
to a count defined by the digital parameter information in the
buffer 330. At the same time, the OR gate output signal is fed to
the input 326 of each interface unit of the type 287 to transfer
the digital parameter information in the buffer 324 through the
buffer 325 and converter 328 to the appropriate inputs of the
system; to the input 322 of each interface unit of the type 286 to
transfer the digital parameter information in the buffer 320
through the buffer 321 and on to the appropriate parameter inputs
of the system; and to the input 315 of each unit of the type 285 to
transfer the digital parameter information in the shift register
310 serially to the appropriate input of the system. Hence, the
section change signal from the section length counter 331 not only
initiates the blanking of raster lines between the raster secitons,
but acts with the vertical reset signal to determine the number of
lines in each raster section, by simultaneously transferring the
digital parameter information in each interface unit which defines
a new raster section to the appropriate inputs of the system.
The signal at the output of the OR gate 371 is also fed through the
conductor 374, a conductor 380, and a conductor 381 to a preset
input of the channel address counter 302 to preset the counter to a
number determined by information fed through a conuctor 382 to a
buffer input 383. The preset number determines the starting count
from which counter 302 addresses the interface units. This count
may vary from raster section to raster section. For example, there
are certain parameters that remain constant from section to section
in a given frame, such as overall X position, overall Y position,
and overall depth as these parameters affect all the sections of
the image. Color parameters might also remain constant. To
illustrate, if the informaiion for these overall parameters
occupies the first 18 interface units, it is necessary to reload
these units after each section. Therefore, the counter 322 should
be preset to begin its address with the 19th interface unit after
the parameter information for the first section of the frame is
transferred. The digital computer 22 is programmed to transmit the
desired preset value to the input buffer 383.
The channel address counter 302 also has an input connected by a
conductor 385 to the output of a delay network 386, the input of
which is connected by a conductor 387 and the conductors 373, 341,
140 and 115 to the vertical reset output of the sync generator 112
(FIG. 4), to reset the counter 302 just before the end of each
frame or field, if there are two fields per frame. The delay
network 386 generates a signal at its output that is delayed from
the vertical reset signal by approximately 90 percent of the time
period between vertical reset pulses. Therefore, in effect, there
is a pulse generated at the output of the delay network 386 that
occurs just prior to each vertical reset pulse after the first
vertical reset pulse is generated. These pulses from the output of
the network 386 are also fed through a conductor 388 to an input of
the digital computer 22 to enable the computer 22 for high speed
transfer of parameter data.
The signal from the output of the OR gate 371 is also fed through
the conductors 374 and 380, and a conductor 391 to an input of the
digital computer 22 to start the high speed transfer from the
computer 22 to the interface units of the digital parameter
information for the next raster section to be generated.
Reviewing the operation of the network of FIG. 6, digital
information is stored wthin the computer 22 definin the parameters
of each raster section of the image to be generated for a given
frame or frames. The origin of the information may be the director
20 which includes controls for setting the value of each set of
parameter information to define each raster section of a particular
frame, or may be some digital recording medium such as the digital
magnetic tape 36 or disc 38 on which is recorded parameter
informatinn defining each raster section of each frame of a
sequence. As the information is being stored, an output pulse from
the delay network 386 is fed through the conductor 388 to initiate
the high speed transfer of the digitial parameter information
defining the first raster section of the first frame which is fed
in a prescribed order in accordance with the digital computer
program from the output of the computer 22 to each of the interface
units of which in this described embodiment there are a total of
43, including four different basic types. The signal at the output
of the delay network 386 initiates the high speed transfer for the
first section parameter data only, the high speed transfer of
parameter data for subsequent sections being initiated by the
vertical reset or section change signals. As the digital parameter
information is fed to the interface units, signals are fed through
the conductor 300 to the channel address counter 302 generating
signals sequentially at a different one of its outputs, each one of
which is connected to a different interface unit to gtte the
appropriate digital parameter information from the computer 22 to
the appropriate one of the interface units. Hence, the interface
units are loaded sequentially with the appropriate information
defining the parameters of the first raster section. When the
gating signal appears at the last output of the channel address
counter 302, indicating that all the interface units are loaded,
this signal is fed through the conductors 308 and 309 to an input
of the computer 22 to stop the high speed tansfer of digital
parameter information.
It will be remembered that the purpose of the interface unit 288 is
to define the number of lines in the raster section currently being
drawn. However, because the information loaded in the interface
units relates to the first raster section, the interface unit 288
cannot perfomr this function as there is no raster section
currently being drawn. Nevertheless, when the next vertical reset
signal is generated by the sync generator 112 it is fed through the
conductors 115, 140, 341, 373 and 372 the OR gate 371, and the
conductor 374 to the inputs 375, 326, 322 and 315 of the interface
units to simultaneously transfer the digital parameter information
loaded in these units and the others like them defining the
parameters of the first raster section to the appropriate parameter
inputs of the system, and to preset the section length counter 331.
This same vertical reset signal is also fed through the conductors
380 and 391 to an input of the digital computer 22 to start the
high speed transfer of digital parameter information defining the
second section to the interface units. The vertical reset signal is
also fed through the conductor 381 to preset the channel address
counter 302 to a number defined by information fed from the
computer 22 through the conductor 382 into its input buffer 383.
The delayed vertical reset pulse at the input 385 to the counter
302 resets the counter 302 just prior to the start of each frame or
field, if there is more than one field per frame.
Along with the other di1ital parameter information from the digital
computer 22 defining the first raster section is information
defining the number of lines in the first raster section which is
now being generated at the output of the analog portion 26. This
information is fed to the interface unit 288 together with the
horizontal reset pulses from the sync generator 112. The section
length counter 331 counts the horizontal reset pulses at its input
332 for a length of time defined by the value of the information
which was transferred from its input buffer 330. When it has
reached a full count, a section change signal is generated at its
output which is fed through the conductors 335 and 337 to the
blanking generator 338 which generates a signal that blanks the
first two or three raster lines of the next raster section (which
would be the second raster section). This same section change
signal is fed through the conductors 335 and 370 and the OR gate
371 to perform the same functions with respect to the second
section as the vertical reset signal did with respect to the first,
that is, to simultaneously transfer the digital parameter
information loaded in the interface units defining the parameters
of the second raster section to the appropriate parameter inputs of
the system and to preset the section length counter 331, to start
the high speed transfer of digital parameter information defining
the third section to the interface units, and to preset the channel
address counter 302 to a number defined by information fed to its
buffer input 383 from the digital computer 22.
The process then repeats itself for the next section and each
succeeding section of the first frame, each time sequentially
loading the interface units with parameter information and
transferring this information simultaneously to the appropriate
inputs of the system to generate the next raster section until the
initial frame is generated. The process is then repeated for each
succeeding frame of the sequence.
If the parameter information stored within the digital computer 22
remains unchanged, each frame will be identical. If however, the
parameter information within the digital computer is changed, as
for example by manipulatinn of the control settings of the analog
input 270 and parameter select input 272 of the director 20, or by
the sequential playback of digital parameter information recorded
on the digital storage medium such as magnetic tape 36 or disc 38
into the digital computer 22, each frame will be different to
produce an animation sequence.
MODULATION OSCILLATORS (FREQUENCY SYNTHESIZER AND FUNCTION
GENERATOR)
Referring to FIGS. 6 and 7, there are shown the frequency
synthesizer 32 and function generator 34 of this invention, the
purposes of which are to generate modulation signals in response to
information received from the digital computer 22 through the
interface units for use in producing depth, vertical and horizontal
modulations by feeding these signals to the inputs 107, 108 and 109
of the analog portion 26. With these s1gnals each raster section
can be formed in a variety of ways to produce a variety of
animation effects. For example, vertical modulation can be used to
bend the raster lines, horizontal modulation to vary the rate at
which a raster line is drawn producing horizontal distortions, and
depth modulation to create depth distortions similar to
foreshortening effects obtained optically with wide angle
lenses.
Many of the major components of the networks of FIGS. 7 and 8 are
discloed in detail in copending U.S. Pat. application Ser. No.
72,642, filed Sept. 16, 1970, now Pat. No. 3,609,917, Frequency
Selector and Synthesizer, which will be referenced where
appropriate.
The frequency synthesizer 32 generates coherent digital signals of
selected frequencies and includes a voltage controlled oscillator
(VCO) and master synthesizer 400, the details of which are shown in
FIGS. 2 and 2A of the referenced application, Ser. No. 72,642. A
minor difference between the synthesizer 400 and the one disclosed
in the referenced application is that its master oscillator has a
frequency of 9.6 megahertz rather than 10 megahertz so as to be
easily divisible to produce the 1.2 megahertz signal. As previously
explained, the 1.2 megahertz signal is fed through the conductor
111 to the input of the sync generator 112 of FIG. 4, for
generating the horizontal and vertical reset signals. With this
difference in master oscillator frequencies, the frequencies
generated at the output of the synthesizer 400 are also reduced by
factors of 0.96 from the output frequencies of the network of FIG.
2 and 2A of the referenced application. These output frequencies,
which need not be described here, since they are clearly desribed
in the referenced application, are fed into a digital frequency
selcctor 401 for producing at its output a digital synthesized
signal which appears on an output conductor 402. By simply
paralleling digital frequency selectors of the type 401, a
plurality of coherent synthesized digital signals can be produced.
For example, in this described embodiment, three such signals are
necessary for vertical, horizontal and depth modulations and
therefore three digital frequency selectors of the type 401 would
be required. Since they are identical only one need be
described.
The frequency of the output signal from the digital frequency
selector 401 is determined by signals from a series of four-to-ten
line decoders 404, 405, 406, 407, 408, 409 and 410. The frequency
selector 401 is basically the same type as disclosed in FIG. 4 of
the referenced application, except that the switches 501 through
507 of that FIG. 4 used to select the synthesized frequency desired
are replaced by the decoders 404 through 410 and a shift register
411. The shift register 411 has an input conductor 412 connected to
a control mode switch 414 having an internal position 415 and an
external position 416. In either mode setting the shift register
411 is loaded with digital parameter information which is fed
through suitable conductors to the decoders 404 throuh 410. Each of
these decoders has 10 outputs representing the number 0 through 9,
one of which is activated in accordance with the binary coded
decimal (BCD) number at its input. The signals at the outputs of
the decoders 404 through 410 perform the same function as the
swtches 501 through 507 of FIG. 4 of the referenced application to
gate the appropriate ones of the output frequencies from the
synthesizer 400 to a series of frequency adders such as the adders
530, 540 and 544 of FIGS. 4 and 5 of the referenced application to
produce at the output of the selector 401 a synthesized signal of
the selected frequency.
With the mode switch 414 in its external position, digital
parameter information defining the frequency of the synthesized
signal is fed serially from the output 316 of an interface uiit of
the type 285 to an inut of the shift register 411. Simultaneously
with the transfer of the parameter information, the clock pulses on
the output conductor 317 of the same interface unit are fed to an
input of the shift register 411 to load the shift register with the
parameter information. After the shift register 411 is loaded, the
digital parameter information in BCD form is fed to the decoders
404 through 410 whih decode the information and feed it to inputs
of the selector 401 for defining the frequency of the synthesized
signal at its output 402. Hence, with the mode switch 414 in its
external position, the frequency of the synthesized signal is
controlled by the digital computer 22.
With the switch 414 in the internal position, the frequency of the
synthesized signal is selected by setting a series of BCD,
seven-place, thumb-wheel switches 420, 421, 422, 423, 424, 425 and
426 to the frequency desired. With the switch 414 in this mode
setting, the digital comuter 22 has no effect in selecting the
frequency of the synthesized signal from the selector 401. The
frequency is controlled exclusively by the settings of the BCD
switches 420 through 426 which feed information in binary coded
decimal form directly through the shift register 411 to the
decoders 404 through 410, the outputs of which define the frequency
of the synthesized signal as heretofore described.
Having defined the frequencies of the modulation oscillators, it is
necessary to define their phases, amplitudes, waveform,, and
synchronization modes. This is accomplished in the function
generator 34 of which there is one for each modulation signal
required. The synthesized digital output signal from the digital
frequency selector 401 of the frequency synthesizer 32 is fed
through the conductor 402 to an input of an updown counter 440
which counts the pulses of the synthesized digital signal
alternately upward and downward between prescribed limits producing
binary weighted outputs which are fed to the input of a digital to
analog converter 442. The converter 442 produces at an output
conductor 444 a stairstep triangular waveform of a frequency
depending on the frequency of the signal from the frequency
synthesizer 32 and the upper and lower limit settings of the
up-down counter 440. For example, if the up-down counter 440 is set
to count alternately up and down between counts of zero and 50, the
frequency of the triangular waveform output from the converter 442
would be 1/100 of the frequency of the synthesized signal. If the
up-down counter 450 is set to count alternately up and down between
counts of zero and 500, the frequency of the triangular waveform
output from the converter 442 is 1/1,000 of the frequency of the
synthesized signal from the frequency synthesizer 32. The up-down
counter 450 and digital to analog converter 442 perform generally
the same function in this circuit as the up-down counter 22 and
digital to analog converter 24 performs in the circuit of FIG. 7 of
the above-referenced application Ser. No. 72,642.
The up-down counter 440 has a triangle/sawtooth enable input 446
which controls whether the counter 440 counts alternately up and
down to produce a triangular waveform from the output conductor 444
or is reset each time it reaches an upper limit (or lower limit) to
produce a sawtooth waveform at the output conductor 444. In either
case the triangle or sawtooth waveform output from the converter
442 is fed through the conductor 444, a conductor 448 and a
resistor 450 to an analog gate 452. The wave form on the conductor
444 is also fed through a side shaper 454 to produce at its output
a sinusoidal waveform which is fed through a conductor 456 and
resistor 458 to an analog gate 460. An output from the up-down
counter 440 is fed through a conductor 462 to a level converter 464
to produce at its output a square waveform which is fed through a
conductor 466 and a resistor 468 to an analog gate 470. Hence, the
counter 440, converter 442, sine shaper 454 and level converter 464
produce triangle, saw tooth, sine and square waveforms from the
digital frequency signal of the frequency synthesizer 32. It is
still necessary however to select a particular one of these
waveforms for each modulation signal, and to define its phase and
synchronization mode.
A shift register 472 receives serial parameter information and
serial clock pulses at input conductors 316 and 317, respectively,
from an interface unit of the type 285, which serial parameter
inforation defines the phase, waveform and synchronization mode of
a particular modulation signal. The phase data information is
transferred from the shift register 472 through suitable conductors
to a phase angle translator 474, while the data defining the
waveform and synchronization mode is transferred through suitable
conductors to a function control circuit 476. The function control
circuit 476 has an input connected by a conductor 478 and the
conductors 333, 334, 116 and 114 to the horizontal reset output of
the sync generator 112 (FIG. 4), and an input connected by a
conductor 480 to the output conductor 337 of the interface unit of
the type 288 for receiving the section change signals.
The function of the phase angle translator 474 and shift register
472 are to set the phase of the modulation waveform. To explain how
this is done, suppose that the counter 440 is made to start from a
count of zero and count alternately between counts of zero and 50
so that a complete cycle is equivalent to 100 counts. For purposes
of establishing a phase for the waveform, a single cycle is divided
into 100 counts with each count equivalent to a particular phase.
The phase angle translaor 474 receives the phase data from the
shift register 472 and converts it to binary weighted outputs which
are fed to the up-down counter 440 to preset its count to a
prescribed number, and also sends a signal either through a
conductor 482, causing the counter 440 to count up, or a conductor
484, causing the counter 440 to count down from the prescribed
number, thereby setting the phase of the waveforms produced
therefrom. The phase data in the shift register 472 has a binary
weight of some number between zero and 100, which data is fed to
the phase angle translator 474. If the data represents a number
between zero and 50, then the phase angle translator 474 transfers
that data directly to the counter 440 together with a signal on the
conductor 482 causing the counter to count up from that number.
However, if the phase data in the shift register 472 represents a
count of between 50 and 100, the output of the shift register would
have no meaning to the counter 440 since it never reaches counts of
over 50. Therefore, the phase angle translator 474 translates data
representing numbers between 50 and 100 to numbers between 0 and 50
which do have meaning to the counter 440. For example, if the data
from the shift register 472 represetts the number 60, to designate
a corresponding phase the translator 474 translates the number 60
to the number 40 and transfers data representing the number 40 to
the counter 440 together with a signal on the conductor 484 causing
the counter 440 to count down. Hence, the purpose of the phase
angle translator 474 is to convert phase data from the shift
register 472 to data that has meaning to the counter 440 for
establishing the phase of its output waveform.
If the counter 440 is in its divide-by-1,000 mode so that it counts
alternately between zero and 500, a complete cycle would have 1,000
counts and the phase data fed through the conductor 316 to the
shift register 472 would represent some count between zero and
1,000 to define the phase of the output waveform from the counter
440.
The fuction control circuit 476 has an output conductor 490 which
carries an enable signal to the gate input of the analog gate 452,
to gate the triangle or sawtooth waveform, as the case may be, from
the output of the converter 442 to the input of a summation
amplifier 491. The function control circuit 476 has another output
conductor 493 which carries an enable signal to the gate input of
the analog gate 460 for gating the sinusoidal waveform from the
sine shaper 454 to the input of the summation amplifier 491. The
function control circuit 476 has another output cnnductor 494 which
carries an enable signal to the gate input to the analog gate 470
to gate the square waveform from the output of the level converter
464 to the input of the summation amplifier 491. The parameter data
in the shift register 472 defining the waveform of a particular
modulation signal is fed to the function control circuit 476 which
sends a signal through the conductor 490, 493 or 494 to gate the
selected waveform signal through the summation amplifier 491 to one
input of a multiplier 496. The multiplier 496 has another input
connected by a conductor 497 to the output conductor 329 of a
interface unit of the type 287 for receiving information defining
the amplitude of the selected waveform.
To produce certain animation effects it is desirable to phase-lock
the modulation signals with the generation of a particular raster
section or with the generation of each raster line of a particular
raster section. The latter synchronization mode might be desirable,
for example, in producing a bend in a raster section where each
line of the raster must be bent at precisely the same place. It
might also be desirable to have no phase lock, allowing the
modulation signal to free run. To provide these synchronization
modes, the parameter data in the shift register 472 defining the
synchronization mode is fed to the function control circuit 476
which, in accordance with the synchronization mode selected,
transmits either the horizontal reset signals at its input
conductor 478, the section change signals at its input conductor
480, or neither if in the free run mode, through an output
conductor 498 to an input of the up-down counter 440. At each pulse
on the input conductor 498, the counter 440 is reset to begin
counting from a phase condition defined by the phase data from the
phase angle translator 474. The function control circuit 476 also
sends a signal through a conductor 499 to the counter 440 to time
the loading of the phase data from the translator 474 into the
counter 440.
Hence, in this manner, a modulation signal of a defined frequency,
phase, waveform, amplitude and synchronization mode is produced at
the output of the multiplier 496 and fed through a conductor 500 to
an appropriate modulation input to the analog portion 26 such as
the input 107, 108 or 109 for use in producing depth, vertical or
horizontal animation. Since three modulation signals are needed in
this embodiment, three function generators of the type described
are required.
INTENSITY COMPENSATION
Referring to FIGS. 4 and 4A, there is shown an intensity
compensation network 520 the details of which are disclosed in
copending U.S. Patent application Ser. No. 74,662, filed Sept. 23,
1970, entitled Beam Intensity Compensator, having an input
conductor 521 connected from an intensity input 522. The input 522
receives analog information from an interface unit of the type 287
defining the beam intensities of the scanning devices of the system
on which the image is produced which devices include the scan
convertors of the color network 67, the X-Y monitors 79, 81 and 83
of FIG. 3, and the overlap network 56 of FIG. 1. The network 520
also has an input conductor 523 connected from the vertical size
input 100 to carry vertical size information, an input conductor
524 connected from the horizontal size input 97 to carry horizontal
size information, an input conductor 525 connected to the output of
the summation amplifier 230 to carry depth information, an input
conductor 526 connected from the vertical modulation input 108 to
carry vertical modulation signals, and an input conductor 527
connected from the horizontal modulation input 109 to carry
horizontal modulation signals. The purpose of the intensity
compensation network 520 is to compensate the beam intensities of
the display devices for variations in size of the image and scan
velocity of the spot as the beam travels across the screen of the
device. The intensity compensation signal for the monitored display
is fed through a conductor 530 to modulate the video signals to the
scan converters or X-Y monitors, and the intensity compensation
signal for the overlap network is fed through a conductor 531 to
modulate the video signal to the overlap network 56.
OPERATION
To describe the operation of the system, it is best to consider an
example of how a particular animation sequence is generated by
referring to FIGS. 8 through 12. Suppose it is desired to produce
an animated sequence of a cartoon caricature of a man walking with
the wind blowing his hat off. The character includes a right arm
601, a right leg 602, a hat 603, a head and body 604, a left leg
605, and a left arm 606. As previously described, an animation
sequence is composed of a finite number of frames, the frequency of
which depends upon whether the sequence is to be filmed, recorded
on video tape, or displayed on a TV monitor. If the sequence is to
be filmed, the frame rate should be 24 frames per second to be
compatible with movie film rates; if the image is to be displayed
on a TV monitor or recorded on video tape for use in the United
States, the frame rate should be 30 frames per second for
compatibility with the US TV scan rate. To produce the sequence, it
is first necessary to establish image parameters for initial and
final frames of the sequence, and the manner in which the image is
to move between initial and final frames, requiring among other
things the selection of the number of frames in the sequence, the
number of raster sections on which the image is to be displayed,
and the fairing functions defining the rates of parameter change
throughout the sequence. All of these variables are in the control
of the operator.
Suppose in this illustration that during the sequence the man takes
one half step from an initial position shown in FIG. 9 to a final
position shown in FIG. 10, and that as he takes the one half step,
his hat is blown off his head as shown in FIG. 10. Further suppose
that his arms and legs move from an initial position to a final
position as shown.
Because there are a total of six different parts 601 through 606 of
the figure moving relative to one another during the sequence, each
of these parts are produced on a separate raster section; the right
arm 601 on a raster section 610, the right leg 602 on a raster
section 611, the hat 603 on a raster section 612, the head and body
604 on a raster section 613, the left leg 605 on a raster section
614, and the left arm 606 on a raster section 615. Therefore,
controls on the director 20 are set to select a total of six raster
sections and to establish the number of raster lines in each
section.
Because the overlap network 56 of FIG. 1 blanks the last generated
overlapping information, the parts of the figures should be
generated from foreground to background. Hence, the raster sections
should be generated in the following order: right arm section 610,
right leg section 611, hat section 612, head and body section 613,
left leg section 614, and left arm section 615. These various body
parts are drawn from top to bottom on a piece of artwork 618 and
displayed such as on the light box 45 of FIG. 1. A video camera
such as the camera 42 of FIG. 1 is made to scan the artwork 618
from top to bottom at rates determined by the horizontal and
vertical reset pulses from the sync generator 112 of FIG. 1.
At this point it should be mentioned that it is not absolutely
necessary that the artwork 618 be arranged so that the camera 42
scans from top to bottom. With the appropriate circuitry, the
camera can be made to scan the various parts of the artwork in any
desired sequence to accommodate the overlap network 56. In any
case, for the purposes of this example, it will be assumed that the
artwork is drawn in the sequence shown and that the camera scans
from top to bottom.
Appropriate controls of the director 20 are set to feed digital
parameter information to the digital computer 22 which in turn is
fed to the switcher 52 as the sequence is generated to switch the
video information from the camera 42 to the input of the grey level
encoder 54 which produces at its output signals representing the
artwork 618 in discrete shades of grey. The output signals from the
grey level encoder 54 are fed to the video gate 58 together with
signals from the output of the overlap network 56 which prevent
overlapping on the part of the image where one part is positioned
behind another, to produce on the output conductor 60 from the
video gate 58 video signals representing the artwork in discrete
shades of grey for use in producing the animation sequence.
The operator must also select the number of frames in the sequence.
This, of course, depends on how fast the figure is to walk, but
assume for purposes of this example that he is to walk at a rate of
half a step per second. With TV rates of 30 frames per second, 30
frames are selected for the sequence by setting the controls on the
director 20. If the sequence is to be filmed, 24 frames are
selected. By adjusting the analog input 270 and channel select 272
controls of the director 20, and by observing the monitor 73 of
FIG. 2, the operator varies all of the parameters for each raster
section of the image necessary to set up the initial frame of the
sequence with the image of FIG. 9. Hence, for each raster section
610 through 615, digital signals are sent sequentially to the
digital computer 22 representing X position, Y position, horizontal
size, vertical size, section depth, and intensity, as well as
signals defining the number of lines in each raster section and the
red, blue and green color components of each color in each frame.
Additionally, the arms, legs, and hat must be made to rotate about
given points between initial and final frames, the hat being made
to rotate about a point 620, the legs about a point 621 located at
the hips, and the arms about a point 622 located at the shoulders.
In this illustration the head and body section 613 remains erect
throughout the sequence although, of course, it could be made to
rotate if desired. Therefore, for each raster section, digital
signals are sent to the digital computer 22 from the director 20
defining the cosine and sine of the angles of rotation, and the
vertical and horizontal axes of rotation.
Certain other parameters must also be defined. It will be noted
that in the initial frame the left arm has a bend at the elbow and
the left leg has a bend at the knee, whereas in the final frame the
right arm has a bend at the elbow and the right leg has a bend at
the knee. Vertical moduation signals are used to produce these
bends, which signals are generated by the frequency synthesizer 32
and function generator 34 from parameter information supplied them
from the digital computer 22. Each of these modulation signals has
five parameters that must be defined: frequency, phase, waveform,
amplitude and synchronization mode. Since elbow and knee bends are
fairly sharp, a triangular waveform is selected as more suitable
than a sinusoidal or square waveform. Also, these bends require
that each raster line of a raster section on which one of the arms
or legs is produced be bent the same amount and in exactly the same
place. Therefore, synchronization mode should be selected such that
the generation of the modulation signals for each raster section is
synchronized with the generation of each raster line in the
section, i.e., with the horizontal reset pulses. Hence, the
controls of the director 20 are set to select a triangular
waveform, synchronization on the horizontal reset signals, and the
appropriate frequency, phase and amplitude for the vertical
modulation signal for each of the raster sections 610, 611, 614 and
615 for the initial frame of the sequence.
In addition to the individual section parameters, the controls of
the director 20 are set to establish the parameters for the overall
image of the initial frame, namely, overall X position, overall Y
position and overall depth.
As all of this parameter information is sent to and stored in the
digital computer 22, the digital computer 22 is programmed to feed
the parameter information for each raster section of the initial
frame to the various interface units, as heretofore described,
beginning with the information defining the raster section 610 and
followed by the information for the raster section 611, 612, 613,
614 and 615, in that order. The channel address counter 302
sequentially directs each piece of digital parameter information to
the appropriate interface unit as heretofore described. Hence,
information defining raster section 610 is first sequentially
loaded into the interface units which information is transferred
from these units to the appropriate input of the other networks of
the system in response to the vertical reset signal from the sync
generator 112, at which time the digital parameter information for
the next section 611 is loaded sequentially into the interface
units and transferred to appropriate inputs of the system in
response to the section change signal at the output of the section
length counter 331 (FIG. 5), and so on for the section 612, 613,
614 and 615 to generate the initial frame of the sequence. The
sections 610 to 615 are, of course, drawn continuously, but two or
three raster lines are blanked at the beginning of each section.
The blanking is produced by signals generated by the blanking
network 338 in response to the section change signals from the
section length counter 331, the horizontal reset pulses, and the
vertical reset pulses. The section change signals in turn are
generated in response to information stored in the digital computer
22 defining the number of lines in each raster section. These
blanking signals from the blanking generator 338 are fed through
the conductor 345 to blank the beam of the scan converter of the
color network 67 between sections.
Upon transfer of each block of parameter information defining each
raster section from the interface units, digital parameter
information is fed from the output of the interface units of the
type 285 to the input of the shift register 411 of the frequency
synthesizer 32 to define the frequency of the vertical modulation
signal, and to the inputs of the shift register 472 of the function
generator 34 for defining the phase, waveform and synchronization
mode of the vertical modulation signal. Also for each raster
section, an analog parameter signal is fed from the output of an
interface unit of the type 287 through the conductor 497 to an
input of the multiplier 496 of the function generator 34 defining
the amplitude of the modulation signal. The result is to produce at
the output conductor 500 of the function generator 34 a series of
modulation signals of frequencies, phases, waveforms, amplitudes
and synchronization modes that produce the bends in the raster
sections 610, 611, 614 and 615 of FIG. 12. The modulation signal
for each raster section is fed to the vertical modulation input 108
of the analog portion 26.
Digital parameter information is fed from interface units of the
type 286 to perform various network control functions such as the
setting of the switch 52 to switch the video information from the
camera 42 through to the grey level encoder 54.
Analog parameter signals are fed from the outputs of the interface
units of the type 287 to the overall X position input 95, section X
position input 96, section horizontal size input 97, section
horizontal axis of rotation input 98, section vertical axis of
rotation input 99, raster vertical size input 100, raster Y
position input 101, overall Y position input 102, section depth
input 103, overall depth input 104, cosine R input 105, sine R
input 106, and intensity input 522 of the analog portion 26. Where
a color display or video tape of the animation sequence is to be
produced, analog voltages from other units of the type 287 are fed
to the color network 67 of FIG. 2 to define the red, blue and green
color components for each discrete grey shade. Where the sequence
is to be recorded on color film, these signals are fed to the RGB
color encoder 77 of FIG. 3.
As the analog parameter signals defining each raster section are
fed to the inputs of the analog portion 26 sequentially by raster
section, the integrators 118 and 144 of the analog portion 26 are
generating horizontal and vertical ramp functions synchronized with
the horizontal and vertical reset pulses from the sync generator
112. Since the video camera 42 also scans in synchronization with
the horizontal and vertical reset pulses from the sync generator
112, the generation of the horizontal and vertical ramp functions
from the integrators 118 and 144 is synchronized with the scan of
the video camera 42 scanning the artwork 618. The horizontal and
vertical ramp functions are combined with the analog parameter
signals at the input of the analog portion 26 as heretofore
described producing, at the output conductors 92 and 93, X and Y
coordinate output signals sequentially representing the raster
sections of the initial frame.
These X and Y coordinate signals are fed to an input of the overlap
network 56 together with the video signals from the output of the
grey level encoder 54 to produce the overlap compensated video
signal on the conductor 60 representing the artwork in discrete
shades of grey. The X and Y coordinate output signals from the
analog portion 26 and the video signals on the conductor 60 can be
fed to the color network 67 to produce a color display of the
initial frame on the color monitor 73. The operator in setting up
the initial frame can observe the effects of varying the controls
of the director 20 on the color monitor 73 until he is satisfied
with the initial frame image.
After he is satisfied with the initial frame, the operator
initiates a control signal on the director 20 to the digital
computer 22 to store the initial frame parameter information in the
computer 22. Having done this, he sets up the parameters for the
final frame in exactly the same manner with the networks
sequentially generating each section of the final frame of the
sequence as the operator varies the controls of the director 20
until he is satisfied with the final frame parameter.
In most cases, the parameters of the final frame are different from
those of the initial frame. For example, in this illustration the X
and Y position and angle of rotation parameters of the hat 603, and
therefore the section 612 are different. The angles of rotation of
the arms about the shoulders and hence the sections 610 and 615 are
different, as are the angles of rotation of the legs about the hips
and hence the sections 611 and 614; also, since the left arm and
left leg go from bent to straight positions, and the right arm and
right leg go from straight to bent positions, the amplitudes of the
vertical modulation signals for the sections 610, 611, 614 and 615
are different.
Having established the initial and final frame parameters for the
sequence, appropriate fairing functions must be selected to define
the rates of change for these parameters throughout the sequence.
Fairing functions can be selected that vary linearly,
exponentially, or in some other manner. To put it in terms of this
illustration, the hat 620 can be made to leave his head very
suddenly and then blow away at a constant rate or perhaps at a
decreasing rate; the arms can be made to bend and straighten at the
elbows in a constant manner throughout the sequence, or perhaps
slowly at first, gradually increasing, and then slowly at the end
of the sequence. The same is true with respect to the straightening
and bending of the knees as well as the rates of rotation of the
hat and each arm and leg throughout the sequence. For purposes of
this example, assume that the hat is to blow off suddenly and then
proceed at a constant rate, and that further it is to rotate from
the position of the initial frame to the position of the final
frame at a constant rate. Therefore, linear fairing functions are
selected to define the parameter changes between initial and final
frames of the raster section 612. Also assume that the bends in the
knees and elbows are to change at a constant rate throughout the
sequence, so that a linear fairing function is selected to define
the amplitude changes of the vertical modulation signals throughout
the sequence. Assume, however, that the rotation of each arm about
its shoulder point 622 and each leg about its hip point 621 is to
begin slowly, gradually increasing at the middle of the sequence,
and then gradually slowing to the end of the sequence. Appropriate
fairing functions are selected to vary the angles of rotation of
the raster sections 610, 611, 614 and 615 accordingly. In selecting
these fairing functions, appropriate command signals are sent from
the director 20 to the digital computer 22 which is programmed to
make parameter calculations in accordance with these selected
functions.
The digital computer 22 now has all the information for defining
the initial and final frames of the sequence as well as the fairing
function information as to how the image parameters should vary
throughout the sequence. With the digital computer 22 programmed to
calculate the section parameters for each frame between initial and
final frames of the sequence in accordance with the fairing
functions selected upon appropriate command from the director 20,
the digital computer 22 goes into its record mode and automatically
computes this information and records it on the digital recording
medium such as magnetic tape 36 and/or disc 38.
With the digital parameter information defining the entire
animation sequence recorded, upon appropriate command from the
director 20 the control network is placed in the playback mode to
play the digital parameter information recorded on the tape or disc
back to the digital computer 22 from which it is fed section by
section and frame by frame as heretofore described to the interface
units. From there it is fed to other inputs of the system to
produce a color display or video tape of the animation sequence.
Also the video signals on the conductor 60 can be fed to the RGB
color encoder 77, and the X and Y coordinate output signals from
the analog portion 26 fed to the X-Y monitors 79, 81 and 83 (FIG.
3) to produce a color film of the sequence.
With this sequence completed, the operator may wish to create a
second sequence with the cartoon character of FIGS. 9 and 10 taking
the second half step. To do this, an initial frame is set up for
the second sequence the same as the final frame of the first
sequence, and a final frame is set up for the second sequence the
same as the initial frame of the first sequence. The operation
heretofore described is then repeated to produce the second
sequence so that now a sequence has been produced of the character
taking a full step. By appropriately rerecording the digital
parameter data for this sequence on the digital magnetic tape 36, a
sequence of any length can be produced of the character
walking.
This example is only meant to illustrate the basic operating
principles of the system and by no means describes the multitude of
animation variations that can be achieved on this system. Indeed,
by appropriately selecting scene length and parameter variations
such as fairing functions and modulation signals, an unlimited
variety of animation effects can ve achieved. As still a further
illustration of the versatility of this system, it should be noted
that once the parameters defining the raster sections, such as the
raster sections 610 through 615, have been established for a given
animation sequence, any figure can be produced thereon and caused
to animate in exactly the same manner by simply changing the
artwork 618. For example, if the artwork 618 where changed to show
the parts of a rabbit, the rabbit would be produced on the raster
sections 610 through 615 and caused to move in the animation
sequence just as the characters of FIGS. 9 and 10. In fact, it may
be desirable in producing certain effects to have no artwork at all
and instead show the raster sections themselves which in the above
exmaple would produce an animation sequence of the rasters shown in
FIGS. 11 and 12.
Various changes and modifications may be made within the invention
as will be readily apparent to those skilled in the art. Such
changes and modifications are within the scope and teaching of this
invention as defined by the claims appended hereto.
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