U.S. patent number RE42,657 [Application Number 11/003,580] was granted by the patent office on 2011-08-30 for dual compression format digital video production system.
This patent grant is currently assigned to Multi-Format, Inc.. Invention is credited to Barry H. Schwab, Kinya Washino.
United States Patent |
RE42,657 |
Washino , et al. |
August 30, 2011 |
Dual compression format digital video production system
Abstract
An audio/video production system is implemented on a PC-based
platform, preferably utilizing various forms of removable magnetic,
optical, or magneto-optical storage media. Specially modified
cameras or other sources provide digitally data-compressed audio
and video program materials in two formats, a first format having a
higher data-compression ratio and intended for use in off-line
systems to develop edit decision lists, and a second format having
a lower data-compression ratio and intended for use in on-line
editing and to produce the final representations of the programs.
Off-line editing decisions may thus be developed on a PC using
removable storage media, and final representations of the programs
may be produced on-line in accordance with stationary-head or
rotary-head digital-tape-based formats, such as DAT, 6-mm or 8-mm
tapes. In an alternative embodiment, automatic and unattended
editing, or extended program playback of more than 40 hours
duration of digital video, is available.
Inventors: |
Washino; Kinya (Little Ferry,
NJ), Schwab; Barry H. (West Bloomfield, MI) |
Assignee: |
Multi-Format, Inc. (Little
Ferry, NJ)
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Family
ID: |
23567794 |
Appl.
No.: |
11/003,580 |
Filed: |
December 3, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
09900784 |
Jul 6, 2001 |
Re. 42020 |
|
|
|
09016777 |
Jan 30, 1998 |
Re. 37342 |
|
|
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08298104 |
Aug 30, 1994 |
5537157 |
|
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|
08050861 |
Apr 21, 1993 |
5450140 |
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Reissue of: |
08396574 |
Mar 1, 1995 |
5488433 |
Jan 30, 1996 |
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Current U.S.
Class: |
348/722 |
Current CPC
Class: |
H04N
5/23203 (20130101); H04N 5/772 (20130101); G06T
9/007 (20130101); H04N 9/8042 (20130101); H04N
5/765 (20130101); G11B 27/34 (20130101); G11B
27/002 (20130101); H04N 5/222 (20130101); G11B
27/032 (20130101); G11B 27/031 (20130101); G06F
3/14 (20130101); H04N 9/7921 (20130101); G09G
2340/02 (20130101); H04N 5/85 (20130101); H04N
9/642 (20130101); H04N 9/8063 (20130101); G11B
2220/90 (20130101); G09G 2340/0407 (20130101); G11B
2220/455 (20130101); H04N 5/915 (20130101); H04N
21/426 (20130101); G11B 2220/41 (20130101); G06F
3/1454 (20130101); G11B 27/034 (20130101); G11B
2220/2525 (20130101); G09G 2340/0442 (20130101); H04N
9/641 (20130101); G11B 2220/2516 (20130101); H04N
5/907 (20130101); H04N 9/8047 (20130101); H04N
5/781 (20130101); G11B 2220/20 (20130101); G11B
2220/61 (20130101); G11B 2220/913 (20130101); G11B
27/024 (20130101) |
Current International
Class: |
H04N
5/76 (20060101) |
Field of
Search: |
;348/722,231-233
;386/52,60,117-120 ;360/14.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Panasonic NAB 95 Catalog. cited by other.
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Primary Examiner: Lee; M.
Attorney, Agent or Firm: Gifford, Krass, Sprinkle, Anderson
& Citkowski, P.C.
Parent Case Text
REFERENCE TO RELATED APPLICATIONS
.Iadd.More than one reissue application has been filed for the
reissue of patent application Ser. No. 09/900,784. The reissue
applications are application Ser. Nos. 11/003,580, filed Dec. 3,
2004 (the present application), 11/003,834, filed Dec. 3, 2004,
11/003,576, filed Dec. 3, 2004, and 11/003,579, filed Dec. 3, 2004,
all of which are continuation reissues of patent application Ser.
No. 09/900,784. .Iaddend.This .Iadd.is a continuation of U.S.
patent application Ser. No. 09/900,784, filed Jul. 6, 2001, now
U.S. Pat. No. Re. 42,020, which is a continuation of U.S. reissue
application Ser. No. 09/016,777, filed Jan. 30, 1998, now U.S. Pat.
No. RE37,342, which is a reissue of U.S. Pat. No. 5,488,433, which
.Iaddend.is a continuation-in-part of U.S. application Ser. No.
08/298,104, filed Aug. 30, 1994.Iadd., now U.S. Pat. No. 5,537,157,
.Iaddend.and U.S. application Ser. No. 08/050,861, filed Apr. 21,
1993, now .[.patented,.]. U.S. Pat. No. 5,450,140.Iadd., the entire
contents of all of which are incorporated herein by
reference.Iaddend..
Claims
Having thus described the system, we claim:
.[.1. A digital audio/video production system adapted for use with
an on-line video editing facility, the production system
comprising: a digital video recorder capable of simultaneously
recording information representative of the same program source
material, including correlated edit-time-code information, onto
first and second removable storage media in first and second
formats, respectively, the information in the first format being
data-compressed relative to the information in the second format; a
programmed personal computer configured to receive the first
removable storage medium, enabling an operator to edit the
information representative of the program source material in the
first format in off-line fashion so as to develop an edit decision
list; and means to transfer the edit decision list to an on-line
video editing facility, the on-line editing facility being further
configured to receive the second removable storage medium, whereby
an operator of the on-line facility may edit the program source
material in the second format using the edit decision list to
create a final video production..].
.[.2. The digital video production system of claim 1, wherein the
information in the second format is non-compressed..].
.[.3. The digital video production system of claim 1, wherein the
digital video recorder forms part of a camcorder..].
.[.4. The digital video production system of claim 1, wherein the
first removable medium is a magnetic hard disk..].
.[.5. The digital video production system of claim 1, wherein the
first removable medium is an optical disk..].
.[.6. The digital video production system of claim 1, wherein the
first removable medium is a magneto-optical disk..].
.[.7. The digital video production system of claim 1, wherein the
second removable medium is a tape drive..].
.[.8. The digital video production system of claim 1, including
digital audio and video program data which are interleaved..].
.[.9. The digital video production system of claim 1, the means to
transfer the edit decision list to the on-line video editing
facility including means to record the edit decision list onto a
third removable storage medium..].
.[.10. The method of producing a final video program, comprising
the steps of: providing video program source material in first and
second digital formats, the material in the first format being
compressed relative to the material in the second format; recording
the material in the first and second formats, respectively, onto
first and second removable storage media along with correlated
edit-time-code information; interfacing the first storage medium to
an off-line video editing system to develop edit decision
information; transferring the edit decision list to an on-line
video editing system; accessing the program material in the second
storage medium using the on-line video editing system; and editing
the material in the second format on the second storage medium in
accordance with the edit decision list to produce a final video
program..].
.[.11. The method of claim 10, the second format being a
non-compressed format..].
.[.12. A digital video production system adapted to deliver program
material and an accompanying edit decision list to an on-line video
editing facility for the purpose of creating a final program, the
system comprising: digital video recording apparatus, including: an
input to receive a video program, means to digitally compress the
program in accordance with more than one compression ratio, an
interface to a first removable storage medium, an interface to a
second removable storage medium, and means to simultaneously record
the video program onto the first removable storage medium at a
first compression ratio and onto the second removable storage
medium at a second compression ratio, the first compression ratio
being greater than the second; and an off-line digital video
editing system, including: an interface to receive the first
removable storage medium. a display to review portions of the video
program, enabling a user to make edit decisions concerning the
program, and an interface to a third removable storage medium to
store a list of the edit decisions, whereby an on-line video
editing facility, upon receiving the second and third storage
medium, may be used to produce a final, edited version of the
program in accordance with the decision list..].
.[.13. The digital video production system of claim 12, wherein the
second compression ratio is zero..].
.[.14. The digital video production system of claim 12, wherein the
off-line digital video editing system forms part of a programmed
personal computer..].
.[.15. The digital video production system of claim 12, wherein the
digital video recorder forms part of a camcorder..].
.[.16. The digital video production system of claim 12, wherein the
first removable medium is a magnetic disk drive..].
.[.17. The digital video production system of claim 12, wherein the
first removable medium is an optical disk..].
.[.18. The digital video production system of claim 12, wherein the
first removable medium is a magneto-optical disk..].
.[.19. The digital video production system of claim 12, wherein the
second removable medium is a tape drive..].
.[.20. The digital video production system of claim 12, including
interleaved digital audio and video program data are
interleaved..].
.[.21. The digital video production system of claim 12, wherein the
program includes separately recorded audio and video
portions..].
.[.22. A digital video recording apparatus adapted for use with an
on-line video editing facility and a personal computer configured
to perform off-line editing, including edit-list development, the
apparatus comprising: a camera outputting information
representative of a video program; means to digitally compress the
program information at a plurality of compression ratios; a
removable disk drive to store a highly compressed version of the
program information suitable for off-line editing using the
personal computer; and a removable tape drive to store a less
compressed version of the program information suitable for on-line
editing; both versions of the program being stored with correlated
edit-time-code information, thereby enabling the on-line editing to
use the edit list developed during off-line editing..].
.[.23. The digital video recording apparatus of claim 22, wherein
the camera, means to digitally compress the program at a plurality
of compression ratios, removable disk drive, and removable tape
drive are all integral to a camcorder..].
.[.24. A digital audio/video production system, comprising: (a)
digital video recording apparatus, including: an input to receive a
video program, first and second removable digital storage media,
and means to simultaneously record the program, including
correlated edit-time-code information, onto the first and second
removable storage media in first and second formats, respectively,
the first format being data-compressed relative to the information
in the second format; (b) a first video editing system, including:
means to receive the first removable storage medium, and controls
enabling an operator to edit the program in the first format and
develop a set of edit decision directives; and (c) a second video
editing system, including: means to receive the second removable
storage medium, means to receive the edit decision directives, and
means to edit the program information in the second format in
accordance with the edit decision directives to create a final
video production..].
.[.25. The digital audio/video production system of claim 24,
wherein the digital video recording apparatus includes means to
receive a plurality of the first removable storage media..].
.[.26. The digital audio/video production system of claim 24,
wherein the second video editing system includes means to receive a
plurality of the second removable storage media, wherein the edit
decision directive being applicable to all of the second removable
storage media received..].
.[.27. The digital audio/video production system of claim 26,
wherein the digital video recording apparatus forms part of a
camcorder..].
.[.28. The digital audio/video production system of claim 26,
wherein the first video editing system forms part of a programmed
personal computer..].
.[.29. The digital audio/video production system of claim 26,
wherein the first removable digital storage medium is a magnetic
disk..].
.[.30. The digital audio/video production system of claim 26,
wherein the first removable digital storage medium is an optical
disk..].
.[.31. The digital audio/video production system of claim 26,
wherein the first removable digital storage medium is a
magneto-optical disk..].
.[.32. The digital audio/video production system of claim 26,
wherein the first removable digital storage medium is a
semiconductor memory..].
.[.33. The digital audio/video production system of claim 24,
wherein the second removable digital storage medium is a magnetic
tape..].
.[.34. A video production method, comprising the steps of:
simultaneously recording information representative of a video
program, plus correlated edit-time-code information, onto first and
second removable digital storage media in first and second formats,
respectively, the program information in the first format being
data-compressed relative to the program information in the second
format; receiving the first removable storage medium at a first
video editing facility and editing the program information at the
first facility in the first format to develop a see of edit
decision directives based upon the edit-mime-code information; and
receiving the second removable storage medium and edit decision
directives at a second video editing facility and editing the
program information at the second facility in the second format in
accordance with the edit decision directives so as to create a
final video production..].
.[.35. The video production method of claim 34, further including
the step of recording the final video production onto a third
removable storage medium at the second video editing
facility..].
.[.36. The video production method of claim 34, further including
the step of outputting the final video production as the program
information is edited in the second format in accordance with the
edit decision directives..].
.[.37. The video production method of claim 34, wherein the step of
editing the program information at the second facility further
includes the step of adding audio special effects in the final
video production..].
.[.38. The video production method of claim 34, wherein the step of
editing the program information at the second facility further
includes the step of adding video special effects in the final
video production..].
.[.39. The video production method of claim 38, wherein the step of
adding video special effects includes the step of adding
titling..].
.Iadd.40. A dual format digital video recording system for
recording a program having audiovisual content, comprising: a first
digital storage medium; a second digital storage medium; a first
digital interface associated with the first digital storage medium
for receiving a first signal representing the audiovisual content
in a first compressed, digital format and edit-time-code
information, wherein the audiovisual content in the first
compressed, digital format and the edit-time-code information are
recorded onto the first digital storage medium; a second interface
associated with the second digital storage medium for receiving a
second signal representing the audiovisual content in a second
compressed, digital format and edit-time-code information wherein
the audiovisual content in the second compressed, digital format
and the edit-time-code information are recorded onto the second
digital storage medium; wherein the edit-time-code information for
the audiovisual content in the first compressed, digital format and
the edit-time code for the audiovisual content in the second
compressed, digital format are correlated; wherein the audiovisual
content in the first compressed, digital format is more compressed
than the audiovisual content in the second compressed, digital
format; and wherein the audiovisual content in the first
compressed, digital format is recorded simultaneously with the
audiovisual content in the second compressed, digital format.
.Iaddend.
.Iadd.41. The dual format digital video recording system of claim
40, wherein the first digital storage medium is a removable storage
medium. .Iaddend.
.Iadd.42. The dual format digital video recording system of claim
40, wherein the second digital storage medium is a removable
storage medium. .Iaddend.
.Iadd.43. The dual format digital video recording system of claim
40, wherein the audiovisual content in the first and second
compressed, digital format comprises a frame rate of substantially
24 frames per second. .Iaddend.
.Iadd.44. The dual format digital video recording system of claim
40, wherein the first signal representing the audiovisual content
in a first compressed, digital format and the second signal
representing the audiovisual content in a second compressed,
digital format comprises a video program, and wherein a complete
copy of the video program is stored on the first digital storage
medium and a complete copy of the program is stored on the second
digital storage medium. .Iaddend.
.Iadd.45. The dual format digital video recording system of claim
40, wherein the digital video recording system forms part of a
camcorder. .Iaddend.
.Iadd.46. The dual format digital video recording system of claim
40, further including random access memory (RAM) for temporarily
storing a portion of the audiovisual content in the first
compressed, digital format. .Iaddend.
.Iadd.47. The dual format digital video recording system of claim
46, wherein the first digital storage medium is removable and
wherein the first digital storage medium is hot-swappable from the
system. .Iaddend.
.Iadd.48. A dual format digital video recording method for
recording a program having audiovisual content, comprising:
providing a first signal representing the audiovisual content in a
first compressed, digital format and edit-time-code information;
providing a second signal representing the audiovisual content in a
second compressed, digital format and edit-time-code information,
wherein the audiovisual content in the first compressed, digital
format is more compressed than the audiovisual content in the
second compressed, digital format and wherein the edit-time-code
information for the audiovisual content in the first compressed,
digital format and the edit-time code for the audiovisual content
in the second compressed, digital format are correlated; and
simultaneously recording the audiovisual content in the first
compressed, digital format with its edit-time-code information and
the audiovisual content in the second compressed, digital format
with its edit-time-code information. .Iaddend.
.Iadd.49. The dual format digital video recording method of claim
48, wherein the audiovisual content in the first compressed,
digital format and its edit-time-code information are recorded onto
a first digital storage medium and wherein the audiovisual content
in the second compressed, digital format and its edit-time-code
information are recorded onto a second digital storage medium.
.Iaddend.
.Iadd.50. The dual format digital video recording method of claim
49, wherein the first and second digital storage media are
removable. .Iaddend.
.Iadd.51. The dual format digital video recording method of claim
48, wherein the audiovisual content in the first and second
compressed, digital format comprises a frame rate of substantially
24 frames per second. .Iaddend.
.Iadd.52. The dual format digital video recording method of claim
49, wherein the first signal representing the audiovisual content
in a first compressed, digital format and the second signal
representing the audiovisual content in a second compressed,
digital format comprises a video program, and wherein a complete
copy of the video program is stored on the first digital storage
medium and a complete copy of the program is stored on the second
digital storage medium. .Iaddend.
.Iadd.53. The dual format digital video recording method of claim
49, wherein the first and second digital storage media are part of
a camcorder. .Iaddend.
.Iadd.54. The dual format digital video recording method of claim
48, further including temporarily storing a portion of the
audiovisual content in the first compressed, digital format on
random access memory (RAM). .Iaddend.
.Iadd.55. The dual format digital video recording method of claim
54, wherein the first digital storage medium is removable and
further including hot-swapping the first digital storage medium.
.Iaddend.
Description
FIELD OF THE INVENTION
This invention relates generally to video recording systems
associated with the editing of program materials, and, more
particularly, to a system that takes advantage of a PC-based
platform for performing non-linear editing functions.
BACKGROUND OF THE INVENTION
Traditional video editing systems are generally divided into two
categories: linear and non-linear. Linear editing systems are
generally integrated with tape-based program storage, while
non-linear editing systems are associated more closely with
disk-based storage media, wherein random-access storage more easily
may be implemented. The typical linear editing system is
implemented with one of the many "broadcast quality" videotape
recording formats. The choices for analog recorders include, among
others, 1'' C-format, Betacam, Betacam-SP, 3/4'' U-matic,
U-matic-SP, S-VHS, and Hi-8. The choices for digital recorders
include, among others, D-1, D-2, D-3, D-5, DCT, and Digital
Betacam. Each of these recording formats is incompatible with any
other format, and all require sophisticated system facilities,
including synchronization systems, edit controllers, audio and
video switchers and processors, digital video effects (DVE)
systems, character generators, and other equipment. This, in turn,
requires extensive physical plant facilities for electric power,
air conditioning and air filtration, storage space, and maintenance
equipment. Furthermore, large operational and maintenance staffs
are required to keep the equipment in good working order. However,
recording duration capacity for these types of videotape recorders
ranges up to three hours or more, making them uniquely valuable for
many applications, such as program distribution, archival storage,
and as master program sources for mass duplication of videos for
the home video market.
In contrast, non-linear systems are based on optical discs, or
alternatively, on magnetic or magneto-optical disks. Because of the
relatively high cost of these storage media when long-duration
recording periods are required, such systems are relegated to use
as off-line editing systems applied to the preparation of edit
decision lists (EDLs) for use in edit suites incorporating linear
editing systems. However, the rapid random-access features and
editing ease are valuable for short programs.
As currently implemented by many manufacturers (such as AVID and
videoCube), PC-based hard disk storage is very expensive. If
equipped with 10 GB of storage capacity, the system, in practice,
is utilized in a two-step process. First, the original unedited
program material is digitized at a high data-compression ratio to
provide representative pictures for use in an off-line editing
environment, whereby the operator may develop an EDL. This EDL then
is used to perform the required editing, using program materials
that have been digitized and stored at much lower data-compression
ratios. Because these two digitizing steps must be performed in
real time, this is an expensive, time-consuming process which
requires well-trained and expensive operational and engineering
personnel.
SUMMARY OF THE INVENTION
It is an object of the invention to integrate the most valuable
features of linear and non-linear editing system approaches.
It is another object of the invention to provide capabilities for
automatic unattended editing from edit decision lists developed on
an off-line editing system.
It is yet another object of the invention to provide a PC-based
digital video recorder for applications such as broadcast
television playback, video duplication source-master playback, or
other related applications.
A further object of the invention is to provide extended playback
of 40 hours or more of digital video programming, for cable
television or other uses.
The present invention achieves these and other objectives by
providing a PC-based audio/video production system which addresses
the problem of providing inexpensive alternatives to the large,
expensive edit suites currently in common use. Digital program
source materials, produced by specially modified cameras or other
sources, provide data-compressed audio and video program materials
in two formats having matched edit-time-code identification. A
first format having a higher data-compression ratio and intended
for use in an off-line editing system is used to develop an edit
decision list, and a second format having a lower data-compression
ratio is used in an on-line editing system for the production of a
final representation of the program. As such, off-line editing
decisions may be developed on a PC, including a portable PC, using
removable storage media, and final representations of the programs
may be implemented on a stationary-head or rotary-head
digital-tape-based format, such as DAT, 6-mm or 8-mm.
By employing one of several new, small, inexpensive storage media
such as PCMCIA-based disk drives, and by utilizing data-compression
technology, the off-line editing capabilities are achieved in an
economical system, with the digital-tape-based formats providing
broadcast-quality required even for demanding applications.
Recording duration capacity for these media is 60 to 120 minutes or
longer for conventional NTSC or PAL video formats, and a natural
extension to HDTV formats (with comparable program duration
capacity) is achieved as commercial availability of storage media
having higher recording densities becomes economically practical.
Where compatibility to film materials is desirable, operation of
the various system components at 24 frames-per-second is
implemented.
A method of producing a final video program according to the
invention therefore includes the steps of providing program source
materials in first and second digital formats, the first format
being characterized in having a higher data compression ratio than
the second; recording the materials in the first and second
formats, respectively, onto first and second removable storage
media along with correlated edit-time-code information in each
case; interfacing the first storage medium to an off-line video
editing system to develop an edit decision list; interfacing the
second storage medium to an on-line video editing system;
transferring the edit decision list developed in conjunction with
the off-line video editing system to the on-line video editing
system; and editing the materials in the second format on the
second storage medium, in accordance with the edit decision list,
to produce a final video program.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic drawing of a portable dual-format digital
video recorder optionally implemented as part of a camcorder
system;
FIG. 2 is a functional block diagram of a dual-format digital video
recorder;
FIG. 3 is an oblique representation of an off-line digital video
editing system implemented with a PC-based edit controller having
provisions for accepting removable storage media; and
FIG. 4 is a block diagram of an on-line digital video editing
system implemented with a PC-based edit controller having
provisions for accepting removable storage media.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a portable dual-format digital video recorder
according to the invention, optionally implemented as part of a
camcorder system. A lens 2 and viewfinder 4 are mounted on the body
of a camera frame. The usual optical-splitter, CCD sensors and
driver circuitry, and digital signal processing circuitry are
located at 6, with optional battery-pack capability being shown at
10. The various analog and digital output signals and any input
audio, video, or control signals, all shown generally at 16, are
interfaced through appropriate connectors disposed on the
rear-panel 12 and sub-panel 14. Provisions are included as shown
for the input of analog audio signals, and for the output of both
analog and digital audio signals. Preferably fiber-optic cabling is
employed as a signal-carrying medium.
The internal video recording facilities are comprised of two parts.
First, a lower data-compression-ratio digital audio/video signal is
recorded on a stationary-head or rotary-head digital data tape
recorder (such as quarter-inch cartridge, half-inch cartridge, DAT,
6-mm or 8-mm) in the removable-tape transport 18, intended for
utilization in an off-line video editing system, described herein
below. Simultaneously, a second digital audio/video signal having a
higher data-compression ratio is recorded on a removable storage
media unit 20. This removable storage medium is intended for
utilization in an off-line video editing system, also described
herein below. In practice, this removable storage medium may be
implemented by any of several well known technologies, such as
magnetic or magneto-optical disks, optical discs, or semiconductor
memory modules. The two signal recording media implemented in the
two parts of the internal video recording facilities may record the
audio and video signals in separated form, or alternatively may be
implemented by any of several well-known systems for interleaved
audio/video data, such as the audio/video interleave ("AVI") system
of Microsoft Corporation, the "M-Power" technique offered by
Hewlett-Packard, or other systems.
Examples of removable storage media include PCMCIA-based removable
disk drives (currently available with capacities of 420 MBytes, and
soon to be available with capacities as high as 1 GByte) and 8-mm.
tape cassettes (currently available with capacity of 20 GB, and
soon to be available with capacities as high as 80 GB). At a
data-compression ratio of 50:1, 420 MBytes will store approximately
75 minutes of program material (in NTSC format using an image
dimension in pixels of 320.times.240 for off-line editing), and at
a data-compression ratio of 5:1, 20 GB also will store
approximately 60 minutes of program material. When the newer 50 GB
or 80 GB tapes become available, these tapes will be capable of
storing either four hours of programming in NTSC or PAL format, or
two hours in an HDTV format, making them practical for use in those
applications currently allocated to linear editing equipment, as
described above. Alternatively, using the currently available
MPEG-2 data compression with a ratio of 20:1, a 20 GB tape will
accommodate four hours of NTSC or PAL recording (or one hour of
HDTV); an 80 GB tape will accommodate 16 hours of NTSC or PAL
recording (or four hours for HDTV). Where compatibility to film
materials is desirable, operation of the various system components
at 24 frames-per-second is implemented.
FIG. 2 is a functional diagram of a storage-device-based digital
recorder according to the invention, either employed in a video
camera, or implemented separately in editing and production
facilities. As shown, a removable hard disk drive 70 and a digital
tape drive 88 are interfaced through an interface bus controller
72. Such a system achieves data transfer rates of 10 MB/sec, and
higher rates on these or other data storage devices, such as
high-capacity removable memory modules, is anticipated. In
practice, alternative methods of storage such as optical or
magneto-optical drives could be utilized, preferably based on
various interface bus standards such as SCSI-2 or PCMCIA. In all
cases, however, in order to ensure compatibility with downstream
editing facilities, both of the removable media for drives 70 and
88 should be recorded with identical or at least correlated
edit-time-code information, so that edit lists developed from one
storage medium will produce the same results when applied to the
program material recorded simultaneously on the other storage
medium.
Microprocessor 74, through user interface provisions 75 (such as
keyboards, touch-screens, etc.) controls the 64-bit or wider data
bus 80, which integrates the various components. Currently
available microprocessors include the Alpha 21064 by Digital
Equipment Corporation, and the MIPS R4400 by MIPS Technologies,
Inc. Future implementations might rely on the already announced P6
by Intel Corp. or the PowerPC 620. An alternative architecture may
be implemented using multiple processors working in parallel to
increase the effective frame rate. The PCI data bus, for example,
is capable of sustained data transfer rates of 100 MB/sec. A ROM 76
is used for fixed program storage. The RAM 78 preferably has the
capacity to function as a buffer, representing 25 seconds or more
of live NTSC video in 4:2:2 format, to enable "hot-swapping" of
removable media without interruption of the input video signal
during recording or alternatively the output video signal during
playback. Graphics processor 82 represents dedicated hardware which
performs the various manipulations required to process input video
signals 84 and to output the video signals 86. Although shown as
Y/R-Y/B-Y format, either the inputs or outputs, or both, may be
configured in alternative formats, such as RGB, YIQ, YUV or other
commonly used alternatives.
While a software-based implementation of the data compression is
possible, a hardware-based implementation is preferred, with the
system employing, for the tape-based drives, a data-compression
ratio of 5:1 for conventional signals (NTSC/PAL) and a 10:1
data-compression ratio for HDTV signals. For the hard-disk drive, a
data-compression ratio of 50:1 is preferably utilized. Examples of
the many available options for this data compression function
include the currently available Apple QuickTime system, fractal
compression, MPEG-1 (for off-line applications) and Motion-JPEG
(for on-line applications). In many applications, MPEG-2 data
compression will be suitable for on-line editing. Audio signals may
be included within the data stream, as proposed in the several
systems for digital television transmission already under
evaluation by the Federal Communications Commission, or by one of
the methods available for integrating audio and video signals used
in multi-media recording schemes, such as the Microsoft ".AVI"
(Audio/Video Interleave) file format. As an alternative, an
independent system for recording audio signals may be implemented,
either by employing separate digital recording provisions
controlled by the same system and electronics, or by implementing
completely separate equipment external to the camera system
described above.
FIG. 3 shows an off-line digital video editing system, implemented
with a PC-based edit controller having provisions for accepting
materials in the form of removable storage media. The controller
102 is preferably of conventional design, but operates at least at
the level of current Intel Pentium or high-level "486" processors.
The unit is equipped with a color display, and preferably includes
a PCI internal bus structure, and provisions for interfacing with a
removable PCMCIA storage card 104. In one embodiment this card 104
is implemented with magnetic or magneto-optical disks, or with an
optical disc unit. Alternatively, a stand-alone external data
storage unit (not shown) could be interfaced through the PCMCIA
facilities, or by way of an SCSI-type interface.
As an optional feature, a PCMCIA expansion adapter 106 may be
provided, so that a plurality of PCMCIA cards or PCMCIA devices 108
may be accessed conveniently through a single PCMCIA slot on the
PC, as shown. This expansion adapter is provided with internal
selection and multiplexing circuitry, so that each plug-in card or
device may be accessed independently and without interference with
any other card or device in the expansion adapter. The selection
may be performed by employing techniques well-known in the art,
such as the addressing schemes utilized for SCSI or GPIB data
busses. Since a single 420 MByte PCMCIA card module is capable of
holding 75 minutes of programming material with image dimensions in
pixels of 320.times.240, 4:2:2 sampling and a 50:1 data compression
ratio, an expansion adapter equipped with ten PCMCIA slots and
plug-in cards is capable of providing ten hours of original program
material, and this programming capacity is capable of being further
expanded with other types of PCMCIA-compatible devices. As a
further option, a custom-designed PC could be provided with
multiple PCMCIA slots to accept a plurality of storage devices
without the need for an external expansion adapter.
In operation, the off-line digital video editing system PC is used
to edit and combine the materials stored on various data-storage
devices, producing an edit decision list which then may be utilized
by an on-line editing system. The availability of multiple storage
devices enables the operator to rehearse and then confirm
"A/B-roll" edits with only two storage devices, and "A/B/C-roll"
edits with three storage devices. When equipped with expansion
provisions or additional SCSI-bus devices, the system is capable of
controlling the various storage devices so as to produce highly
complicated sequences in a convenient and timely manner. While the
lower-quality (higher data-compression ratio) program materials are
utilized only for determining the edit points (edit decision list)
for the program, the off-line editing system described herein below
is capable of producing the final edited version of the program
with high-quality results in accordance with the preferred
embodiment.
The versatility of the system may be further enhanced if planning
for the program is begun by providing script and staging
information to the computer in advance of editing, or even in
advance of filming or taping the original production. The script
may be provided as a simple text file, or as a formatted word
processor file, such as used in "WordPerfect" or "Word for
Windows". As an alternative, the file may be of a custom format, as
is commonly used by professional scriptwriters. This script and
staging information is then reformatted to include specific
commands, such as when to switch camera coverage to a particular
actor, or the choice of a particular camera angle. Further details
may now be included, such as the ability to identify close-up
camera coverage, or points at which specific visual special effects
(such as split-screen views or chroma-keyed backgrounds) or sound
effects are to be incorporated. The modified script file is then
used to guide the operator of the off-line editing system in making
edit decisions to match the program materials to the script, to
make any modifications to the script that are necessitated by the
circumstances of the taping, or to take advantage of any unforeseen
artistic opportunities presented by the actual taped materials.
In addition, it is common practice in broadcast-television news
studios to use remotely controlled cameras to telecast the live
programs. These cameras are mounted on motorized bases which are
capable of moving the cameras to any desired position on the stage,
within the physical limits imposed by the stage itself (such as the
length of the camera cables or the clearance available for cameras
to move relative to each other on the stage). The zoom-lenses,
pan-tilt mounts, and camera electronic control settings are
manipulated through the camera remote-control facilities, which may
include either separate electronic control panels or alternatively
computer interfaces with appropriate control software, such as the
unit described by Washino, U.S. Pat. No. 5,325,202. By coupling the
software script materials to instructions for control of the camera
movements, the capabilities of all of these systems may be
optimized. The modified script file must be prepared before the
actual taping occurs, however, and should include the physical
layout of the sets and props for each scene.
The staging information described herein above, is identified by
special camera-remote-control software, and the camera control
operator is provided with a graphical interface which depicts the
layout of the set and the "blocked" positions of the actors and
props for a given scene. This system preferably also includes a
user interface (such as a touch-screen or a mouse) to enable the
camera control operator to program the cameras to be in the correct
location, and to have the correct zoom-lens and pan-tilt positions,
to capture the scene as desired, as described in co-pending
application U.S. Ser. No. 08/050,861. At this time, the operator
optionally may add information to control automated lighting
systems, which are well-known in the art of the film, video, and
stage production. This enhanced version of the modified script file
is then used to direct camera actions during the actual taping of
the scenes, and is further modified as part of the off-line editing
process as the EDL is developed, as described above, in accordance
with the invention.
An on-line digital video editing system is depicted in
block-diagram form in FIG. 4. The functional operation of the
editing system follows that of the digital video editing system
disclosed in FIG. 2, or in an alternative embodiment, may be
implemented in a more sophisticated form, as described in our
co-pending application "Multi-Format Audio/Video Production
System," U.S. application Ser. No. 08/298,104 filed Aug. 30, 1994.
This system is implemented with a PC-based edit controller 206
having separate provisions for accepting removable storage media.
In the preferred embodiment, the digital video tapes recorded by
the system of FIG. 2 are installed in a tape-storage "jukebox" 208
for easy access during editing. Such tape cassette handling devices
are well-known in the art of computer data storage, and are
generally utilized for data back-up applications or for archival
storage.
The edits incorporated into the edit decision list are utilized to
sequence the various digital tapes so as to assemble a recording of
the desired program materials into a final finished product, which
is then recorded on the videotape recorder 202. This video recorder
may be implemented as any of the commonly used choices for analog
recorders, including, among others, 1'' C-format, Betacam,
Betacam-SP, U-matic-SP, and Hi-8. If implemented as a digital
recorder, the available choices include, among others, D-1, D-2,
D-3, D-5, DCT, and Digital Betacam. Furthermore, the final format
could be another digital data tape such as the type used for
program source material or any other removable storage media. Since
the time-code identification numbers on the removable media of the
off-line system correlate with those utilized in the on-line
system, no conversion or adaptation of the edit decision list is
needed. The video monitor 204 is used to manipulate the
windows-based edit system control software, and to view the program
materials as the edit process proceeds. This process will be
essentially automatic, as all of the necessary decisions already
have been made in the off-line editing process as described above.
In addition, this is an appropriate time for adding digital video
effects to the program or to implement any special effects included
in the program script.
The invention may be used for other applications limited to
record/playback, without implementing the full range of editing
features. For example, in applications such as master playback for
video duplication, the program master tape must be played, rewound
to the beginning, and then restarted, on a repeating cycle. In
facilities employing a conventional video tape recorder, this
represents a great deal of physical stress on the program master
tape, thereby requiring a large number of copies of this master
tape when many production runs are required to complete an order.
In addition, some production time is lost due to the rewinding
process itself. In a disk-based application of the system disclosed
herein, there is no significant deterioration of the master program
even in repeated usage, and it is possible to begin playing a
program at any point desired, with essentially no delay due no
cueing the program media to the physical location containing that
part of the recorded program. In order to provide the necessary
recording time duration, additional hard-disk drives would be added
to achieve the required playback duration. Based on an MPEG-2
data-compression ratio of 20:1 (with a 4:2:2 recording system for
NTSC signals), two hours of digital video would require
approximately 8 GB of disk storage capacity. Disk-drives offering
capacity of 9 GB are currently available, and until removable media
achieve comparable levels, a program would accordingly be loaded
into internal or external disk-storage units from the required
number of removable media units.
The invention may also be employed as a playback unit for cable
television usage or other extended-playing time applications. By
adding as many "juke-box" units as desired, it is a simple matter
to extend the playback time capability of the system, with each
"juke-box" providing approximately 40 hours of digital video
playback. By fully utilizing the RAM-based audio/video buffering
capabilities discussed with reference to FIG. 2, it is possible to
supply digital video playback on a continuous basis by changing the
tape storage cassettes or cartridges "on-the-fly" while video
playback proceeds. If provided with computer-readable
identification codes on each cassette or cartridge, the computer is
able to locate the "juke-box" and the particular physical storage
slot containing program materials that previously have be scheduled
for playback. Identification and library management systems of this
type are well-known in the art, and are in common usage implemented
as "cart-machines" employed for playback of commercial
advertisements or other program materials at broadcast stations. In
addition, playback at any frame rate or television system standard
would be available, in accordance with our co-pending U.S.
application Ser. No. 08/298,104 filed Aug. 30, 1994.
The versatility of the Digital Video Production System may be
enhanced further, if planning for the program is begun by providing
script and staging information to the computer in advance of
editing, or even in advance of filming or taping the original
production. Computer software having access to the script materials
will enable the operator to match the scenes to the recorded video
materials quickly, thereby speeding the editing process. In
addition, it is common practice in broadcast-television news
studios to use remotely-controlled cameras to telecast the live
programs. By coupling the software script materials to instructions
for control of the camera movements, the capabilities of all of
these systems will be optimized.
* * * * *