U.S. patent application number 13/796742 was filed with the patent office on 2013-07-25 for imaging device.
This patent application is currently assigned to NIKON CORPORATION. The applicant listed for this patent is Nikon Corporation. Invention is credited to Takashi KURIYAMA.
Application Number | 20130188921 13/796742 |
Document ID | / |
Family ID | 45010325 |
Filed Date | 2013-07-25 |
United States Patent
Application |
20130188921 |
Kind Code |
A1 |
KURIYAMA; Takashi |
July 25, 2013 |
IMAGING DEVICE
Abstract
An imaging device includes an imaging sensor that outputs an
imaging signal representing a sequence of frame images of a
photographic subject. A buffer memory temporarily stores data of
the sequence of frame images from the imaging signal. A release
switch is actuated by a user to output an image-taking signal. A
controller, upon receipt of the image-taking signal from the
release switch: (i) generates moving image data from at least some
of the plurality of frame images stored in the buffer memory, (ii)
generates at least one piece of still image data based on at least
one frame image of the plurality of frame images stored in the
buffer memory, and (iii) associates the moving image data with the
still image data and records the moving image data and the still
image data in a recording medium.
Inventors: |
KURIYAMA; Takashi;
(Yokohama-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Nikon Corporation; |
Tokyo |
|
JP |
|
|
Assignee: |
NIKON CORPORATION
Tokyo
JP
|
Family ID: |
45010325 |
Appl. No.: |
13/796742 |
Filed: |
March 12, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13093557 |
Apr 25, 2011 |
8422868 |
|
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13796742 |
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Current U.S.
Class: |
386/225 |
Current CPC
Class: |
H04N 9/79 20130101; H04N
5/772 20130101; H04N 9/8042 20130101; H04N 5/23245 20130101; H04N
5/907 20130101; H04N 5/2621 20130101 |
Class at
Publication: |
386/225 |
International
Class: |
H04N 9/79 20060101
H04N009/79 |
Foreign Application Data
Date |
Code |
Application Number |
May 25, 2010 |
JP |
2010-119424 |
Claims
1. An imaging device comprising: an imaging sensor that outputs an
imaging signal representing a sequence of frame images of a
photographic subject; a buffer memory that temporarily stores data
of the sequence of frame images from the imaging signal; a release
switch that is actuated by a user to output an image-taking signal;
and a controller that is coupled to the release switch and the
buffer memory, and that, upon receipt of the image-taking signal
from the release switch: (i) generates slow motion moving image
data from at least some of the plurality of frame images stored in
the buffer memory, the slow motion moving image data to be played
at a second frame rate lower than a first frame rate at which the
frame images were output per unit time by the imaging sensor, (ii)
generates at least one piece of still image data based on at least
one frame image of the plurality of frame images stored in the
buffer memory, and (iii) associates the slow motion moving image
data with the still image data and records the slow motion moving
image data and the still image data in a recording medium.
2. The imaging device according to claim 1, wherein the slow motion
moving image data has a predetermined time duration.
3. The imaging device according to claim 2, wherein the
predetermined time duration is set in advance of outputting the
imaging signal by the imaging sensor.
4. The imaging device according to claim 2, wherein the at least
one frame image of the plurality of frame images from which the at
least one still image data is generated is neither a first frame
image nor a last frame image of the plurality of frame images
stored in the buffer memory during the predetermined time
duration.
5. The imaging device according to claim 1, wherein a single
actuation of the release switch causes the controller to generate
the slow motion moving image data and the still image data, and
record the slow motion moving image data and the still image data
in the recording medium.
6. The imaging device according to claim 1, further comprising the
recording medium, which is removably attachable to the imaging
device.
7. The imaging device according to claim 1, further comprising: a
display by which the slow motion moving image data and the still
image data can be played back for viewing, wherein the controller
generates display image data to be displayed on the display from
the slow motion moving image data and the still image data
associated with the slow motion moving image data, the controller
generating the display image data so that a still image generated
from the at least one piece of still image data is displayed after
a moving image generated from the slow motion moving image data is
displayed.
8. The imaging device according to claim 1, wherein the imaging
device is an electronic camera.
9. The imaging device according to claim 8, further comprising: a
display by which the slow motion moving image data and the still
image data can be played back for viewing, wherein the controller
generates display image data to be displayed on the display from
the slow motion moving image data and the still image data
associated with the slow motion moving image data, the controller
generating the display image data so that a still image generated
from the at least one piece of still image data is displayed after
a moving image generated from the slow motion moving image data is
displayed.
10. The imaging device according to claim 1, wherein: the
controller generates the slow motion moving image data based on the
plurality of frame images stored in the buffer memory during a
first predetermined time that ends when the image-taking signal is
output by the release switch, and based on the plurality of frame
images stored in the buffer memory until an end of a second
predetermined time that starts when the image-taking signal is
output by the release switch, and the controller generates the
still image data based on the frame image stored in the buffer
memory when the image-taking signal is output by the release
switch, or during one of the first and second predetermined
times.
11. The imaging device according to claim 1, wherein each of the
frame images stored in the buffer memory has a number of pixels
that is equal to or larger than an HDTV standard in number of
pixels.
12. The imaging device according to claim 1, wherein the still
image data is equal to or larger than the slow motion moving image
data in number of pixels.
13. The imaging device according to claim 1, wherein the second
frame rate is 0.4 of the first frame rate.
14. An imaging device that includes a playback mode, the imaging
device comprising: a memory that stores moving image data and still
image data associated with the moving image data, the moving image
data including a plurality of frame images based on an imaging
signal from an imaging sensor that images light from a subject, the
still image data including a piece of still image data based on a
frame image of the plurality of frame images; and a controller that
generates display image data to be displayed from the moving image
data and the still image data associated with the moving image
data, the controller generating the display image data so that a
still image generated from the piece of still image data is
displayed after a moving image generated from the moving image data
is displayed.
15. The imaging device according to claim 14, wherein the moving
image data is slow motion moving image data that is displayed at a
second frame rate lower than a first frame rate that represents the
number of the frame images output per unit time by the imaging
sensor.
16. The imaging device according to claim 15, wherein the second
frame rate is 0.4 of the first frame rate.
17. The imaging device according to claim 14, wherein the moving
image data has a predetermined time duration.
18. The imaging device according to claim 17, wherein the
predetermined time duration is set in advance of outputting the
imaging signal by the imaging sensor.
19. The imaging device according to claim 17, wherein the frame
image of the plurality of frame images from which the still image
data is generated is neither a first frame image nor a last frame
image of the plurality of frame images included in the moving image
data during the predetermined time duration.
20. The imaging device according to claim 14, wherein the memory is
removably attachable to the imaging device.
21. The imaging device according to claim 14, further comprising: a
display by which the display image data is displayed.
22. The imaging device according to claim 14, wherein the imaging
device is an electronic camera.
23. The imaging device according to claim 22, further comprising: a
display by which the display image data is displayed.
24. The imaging device according to claim 14, wherein each of the
frame images stored in the memory has a number of pixels that is
equal to or larger than an HDTV standard in number of pixels.
25. The imaging device according to claim 14, wherein the still
image data is equal to or larger than the moving image data in
number of pixels.
26. The imaging device according to claim 14, wherein: the
controller generates the moving image data based on the plurality
of frame images stored in a buffer memory during a first
predetermined time that ends when an image-taking signal is output
by a release switch of the imaging device, and based on the
plurality of frame images stored in the buffer memory until an end
of a second predetermined time that starts when the image-taking
signal is output by the release switch, and the controller
generates the still image data based on the frame image stored in
the buffer memory when the image-taking signal is output by the
release switch, or during one of the first and second predetermined
times.
27. An imaging device comprising: an imaging sensor that outputs an
imaging signal representing a sequence of frame images of a
photographic subject; a buffer memory that temporarily stores data
of the sequence of frame images from the imaging signal; a release
switch that is actuated by a user to output an image-taking signal;
and a controller that is coupled to the release switch and the
buffer memory, and that, upon receipt of the image-taking signal
from the release switch: (i) generates moving image data from at
least some of the plurality of frame images stored in the buffer
memory, (ii) generates at least one piece of still image data based
on at least one frame image of the plurality of frame images stored
in the buffer-memory, and (iii) associates the moving image data
with the still image data and records the moving image data and the
still image data in a recording medium.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of U.S. patent application Ser. No.
13/093,557 filed Apr. 25, 2011, the disclosure of which is
incorporated by reference herein in its entirety. The disclosure of
the following priority application also is incorporated hereby
reference in its entirety:
[0002] Japanese Patent Application No. 2010-119424, filed on May
25, 2010.
TECHNICAL FIELD
[0003] The present invention relates to an imaging device that can
record a moving image.
BACKGROUND ART
[0004] A recording device is proposed in which a moving image
starts to be temporarily stored when moving image-incorporated
still image capturing mode is set; and a captured still image is
recorded and a moving image is generated from any one of the
following moving images and recorded when a shutter button is
pressed: a moving image that has been temporarily stored before the
still image is captured, a moving image converted from the captured
still image, and a moving image captured after the shutter button
is pressed (refer to, for example, WO2006/028172).
SUMMARY OF INVENTION
[0005] However, in regard to known imaging devices equipped with
the recording device disclosed in WO2006/028172, no technology is
disclosed in which a moving image having an impressive digital
video effect such as a slow motion moving image where a subject
appears to move more slowly than actual movement is captured in
synchronization with the timing at which the still image is
captured, and the moving image and the still image are associated
with each other and recorded.
[0006] An object of the invention is to provide an imaging device
capable of capturing a slow motion moving image with high
resolution and extreme precision in an automatic manner, in
relation with timing of capturing a still image with high
resolution and extreme precision.
[0007] An imaging device according to the invention includes a
storage unit that sequentially stores a plurality of frame images
based on an imaging signal from an imaging sensor that images light
from a subject, a moving image data generation unit that generates
slow motion moving image data to be played at a second frame rate
lower than a first frame rate that represents the number of the
frame images stored per unit time in the storage unit, based on the
plurality of frame images stored in the storage unit for a
predetermined time period, a still image data generation unit that
generates at least one piece of still image data based on at least
one frame image of the plurality of frame images stored during the
predetermined time period in the storage unit, and a record control
unit that associates the slow motion moving image data generated by
the moving image data generation unit with the still image data
generated by the still image data generation unit and records the
moving image data and the still image data in a recording
medium.
[0008] According to the imaging device of the invention, it is
possible to capture the slow motion moving image with high
resolution and extreme precision and to capture the still image
with high resolution and extreme precision in parallel, at
synchronized timing.
BRIEF DESCRIPTION OF DRAWINGS
[0009] FIG. 1 is a block diagram illustrating a system
configuration of an electronic camera according to an
embodiment.
[0010] FIG. 2 is an explanatory diagram illustrating a frame rate
for storing a slow motion moving image in a buffer memory and a
frame rate for recording the slow motion moving image in a recoding
medium at the time of capturing the slow motion moving image.
[0011] FIG. 3 is a flowchart illustrating a process performed when
the slow motion moving image and a still image are captured in the
electronic camera according to the embodiment.
[0012] FIG. 4 is a diagram illustrating an exemplary display on a
display unit.
[0013] FIG. 5 is a diagram illustrating an exemplary indication by
an indicator.
[0014] FIG. 6 is an explanatory diagram illustrating another
example of the frame rate for recording the slow motion moving
image in the recording medium at the time of capturing the slow
motion moving image.
DESCRIPTION OF EMBODIMENTS
[0015] Hereafter, an electronic camera as an imaging device
according to an embodiment of the present invention will be
described with reference to the accompanying drawings. FIG. 1 is a
block diagram illustrating a system configuration of an electronic
camera 2 according to a first embodiment. As illustrated in FIG. 1,
the electronic camera 2 is configured by a microprocessor and the
like. The electronic camera 2 includes a control unit 4 that
collectively controls over respective units of the electronic
camera 2. The control unit 4 is connected with an imaging sensor 6,
a buffer memory 8, a recording medium 10, a display unit 12, an
operation unit 14, and a detection unit 16.
[0016] The imaging sensor 6 is configured by a CCD, CMOS or the
like, and images light from a subject through an image-capturing
lens (not shown). The control unit 4 acquires image data based on
an imaging signal that is a digital signal obtained by converting
an analog signal output from the imaging sensor 6 using an A/D
converter (not shown).
[0017] The buffer memory 8 temporarily stores image data produced
based on the imaging signal from the imaging sensor 6. In
particular, when the electronic camera 2 is set, for example, to
slow motion moving image capturing mode or the like in which a slow
motion moving image (to be described below and also referred to as
a slow moving image hereinafter) is captured, the buffer memory 8
sequentially stores a plural number of pieces of image data based
on the imaging signal output from the imaging sensor 6 in
synchronization with a moving image cycle (60 fps or the like),
that is, a plurality of frame images constituting the slow moving
image. In this case, the frame images, each having the number of
pixels matching or exceeding the standard (1280.times.720 pixels or
more) of high definition television (HDTV), that is, so-called high
resolution frame images are sequentially stored in the buffer
memory 8 in a first-in first-out (FIFO) manner.
[0018] More specifically, in a case where the buffer memory 8 has a
storage area that is allowed to store, for example, n (n is a
natural number) frame images, as illustrated in FIG. 2(a), the
control unit 4 performs control such that a first frame image F1
obtained through a first acquisition, a second frame image F2
obtained through a second acquisition, . . . , and an n-th frame
image Fn obtained through an n-th acquisition are sequentially
stored in the buffer memory 8. In a case where a subsequent frame
image Fn+1 is output from the imaging sensor 6 after n frame images
F1 to Fn are stored in this way, the oldest frame image F1 is
removed from the buffer memory 8 and the newest frame image Fn+1 is
stored instead. Whenever a subsequent frame image is output from
the imaging sensor 6, a process of removing the oldest frame image
and storing the newest frame image is repeatedly performed.
[0019] That is, the buffer memory 8 includes n addresses (storage
areas to sequentially store the frame images), and stores
sequentially the first frame image F1 in an address of address
number (n-1), the second frame image F2 in an address of address
number (n-2), . . . , and the n-th frame image Fn in an address of
address number 0. That is, the frame images F1 to Fn are stored in
all of the n addresses, the subsequent frame image Fn+1 is output,
and the frame image (that is, the oldest frame image) F1 in the
address of address number (n-1) is deleted. Then, the respective
frame images F2 to Fn are shifted from the addresses of address
number (n-2) to address number 0 so as to be stored in the
addresses of address number (n-1) to address number 1,
respectively, and the (n+1)-th frame image (that is, the newest
frame image) Fn+1 is stored in the address of address number (0).
Accordingly, the newest frame image is always stored in the address
of address number (0), and the address with the greater address
number stores the older frame image. The address with address
number 0 stores the newest frame image at all times.
[0020] The recording medium 10 is a potable type recording medium
that is removably installed in a card slot (not shown) provided in
the electronic camera 2. For example, a CF card, an SD card, a
smart media, or the like is used as the recording medium. In the
recording medium 10, moving image data and slow moving image data
are recorded. The moving image data and the slow moving image data
are produced by subjecting each of the frame images stored in the
buffer memory 8 to a resizing process (resizing from a high
resolution to a low resolution) to achieve a resolution suitable
for a moving image, which is performed by a reduction circuit (not
shown) in the control unit 4, a moving-image image process
performed by a moving image signal processing circuit (not shown)
in the control unit 4, and a moving image compression process
performed by a moving image compression circuit (not shown) in the
control unit 4. In the recording medium 10, information related to
image-capturing and still image data are also recorded. The still
image data is obtained by subjecting the frame image stored in the
buffer memory 8 to a still-image image process performed by a still
image signal processing circuit (not shown) in the control unit 4
and a still image compression process performed by a still image
compression circuit (not shown) in the control unit 4.
[0021] The display unit 12 is configured by a monitor including an
LCD and the like provided on the rear surface of the electronic
camera 2, or an EVF or the like including an LCD and the like. The
display unit 12 displays a through image based on the imaging
signal from the imaging sensor 6, a moving image based on the
moving image data recorded in the recording medium 10, a slow
moving image based on the slow motion moving image data
(hereinafter, referred to as slow moving image data), a still image
based on the still image data, and information related to the
image-capturing. The operation unit 14 is configured by including a
power supply switch operated for turning on/off the power supply of
the electronic camera 2, a command dial operated for setting
image-capturing mode such as moving image capturing mode for
capturing a moving image or slow motion moving image capturing mode
for capturing a slow moving image, a release button operated for
entering instructions such as an instruction to start capturing of
a moving image or a still image, a menu button operated for
displaying menu items or the like on the display unit 12, a cross
key operated for selection of a menu item or the like or for
setting various conditions, an OK button operated for confirmation
of the operation such as selection of a menu item or setting of
various conditions, and the like.
[0022] The detection unit 16 is configured by including an attitude
sensor and the like and detects information related to a change in
the attitude of the electronic camera 2 relative to a subject at
the time of capturing the slow moving image in the electronic
camera 2. The control unit 4 controls an ending time of the
capturing of the slow moving image based on the detection result
from the detection unit 16. Instead of including the attitude
sensor, the detection unit 16 may be configured by employing a
structure that detects information related to a change in the
attitude of the electronic camera 2 by detecting a change in
movement of a subject, based on at least two frame images having a
resolution suitable for the detection of attitude change of the
electronic camera 2, at first which are produced based on the
imaging signal from the imaging sensor 6 and then subjected to a
resizing process (resizing from a high resolution to a low
resolution) performed by the reduction circuit (not shown) in the
control unit 4.
[0023] In the electronic camera 2 according to this embodiment, the
slow moving image data that is to be played at a second frame rate
lower than a first frame rate that represents the number of frame
images being stored per unit time in the buffer memory 8 after
being output from the imaging sensor 6 is generated. The still
image data is generated based on at least one frame image out of
the plurality of frame images that constitute the slow moving image
data. The generated slow moving image data and the still image data
can be recorded in the recording medium 10 in association with each
other. Hereinafter, a process performed at the time of capturing
the slow moving image and the still image in the electronic camera
2 according to the embodiment will be described with reference to a
flowchart illustrated in FIG. 3.
[0024] In this embodiment, the slow moving image data is generated
based on a plurality of frame images stored in the buffer memory 8
for a time period from a time at which the frame image to become
the still image data is stored in the buffer memory 8 to the
beginning of a first predetermined time period, and a plurality of
frame images stored in the buffer memory 8 for a time period, that
is, until the end of a second predetermined time period after the
frame image to become the still image is stored in the buffer
memory 8. That is, the slow moving image data is generated based on
the plurality of frame images stored in the buffer memory 8 during
a predetermined time period (the first predetermined time period
the second predetermined time period), and the still image data is
generated based on the frame image stored in the buffer memory 8 at
the ending time of the first predetermined time period (that is,
the beginning time of the second predetermined time period).
Furthermore, the predetermined time period (for example, 1 second
or the like), the first predetermined time period (for example, 0.6
second or the like), and the second predetermined time period (for
example, 0.4 second or the like) are set in advance and stored in a
memory (not shown) in a rewritable manner. In other words, the slow
moving image data is generated based on the plurality of frame
images stored from the beginning of the first predetermined time
period, which begins before the frame image to become the still
image data is stored in the buffer memory 8, until the end of the
second predetermined time period, which ends after the frame image
to become the still image is stored in the buffer memory 8.
[0025] First, when a user operates the command dial to set the slow
motion moving image capturing mode, the control unit 4 switches to
the slow motion moving image capturing mode for capturing the slow
motion moving image and the still image associated with the slow
motion moving image. Then, it is determined whether or not the user
has half-pressed the release button (Step S10). When it is
determined that the release button is half-pressed in Step S10, the
control unit 4 determines that an instruction to prepare generation
of the still image data and an instruction to generate the slow
moving image data are given. Accordingly, as shown in FIG. 4, the
control unit 4 performs control such that the display unit 12
displays the through image 20 and the indicator 22 thereon, and a
focus lens (not shown) or the like is driven to move a focus
position toward a main subject for the main subject in the through
image 20 to be on focus. Then, it is determined whether or not the
main subject is on focus (Step S11). The indicator 22 has a
function of indicating to the user where the current time point is
within the time span between the beginning and end (that is, over
the entire period during which the slow moving image is generated)
of the predetermined time period (in other words, indicating where
the current time point is within the time span between the
beginning and end of the first predetermined time period and where
the current time point is within the time span between the
beginning and end of the second predetermined time period).
Referring to FIG. 4, a bar 22c (described below, see FIG. 5) inside
a frame 22a of the indicator 22 is not displayed. No display of the
bar 22c means an operation stage before the beginning of the first
and second predetermined time periods. A mark 22b represents the
ending time of the first predetermined time period (the beginning
time of the second predetermined time period), that is, the mark
22b means that the full-pressing operation of the release button in
Step S13 to be described below is executed. The indicator 22 will
be described below in detail.
[0026] When it is determined that the main subject is on focus in
Step S11 (Yes in step S11), the control unit 4 performs control
such that the capturing of the slow moving image is started, that
is, the buffering into the buffer memory 8 and the indication of
the current time point by the indicator 22 are started (step S12).
Specifically, as described above, the control unit 4 performs
control such that the plurality of frame images F1, . . . , and Fn
. . . (see FIG. 2) produced based on the imaging signal, which is
output from the imaging sensor 6 in synchronization with the moving
image cycle, start to be stored in the predetermined addresses in
the buffer memory 8. Next, when the buffering into the buffer
memory 8 is started, the control unit 4 starts control of causing
the indicator 22 to indicate the progress of buffering, that is,
which time point of buffering between the beginning and end of the
predetermined time period (the first predetermined time period) is
being executed at the current time point. That is, at the time
prior to the beginning of the predetermined time period (the first
predetermined time period), as shown in FIGS. 4 and 5(a), nothing
is displayed inside the frame 22a of the indicator 22. However,
when the buffering is started, as shown in FIG. 5(b), the display
of the bar 22c is started from the left end of the frame 22a. As
the frame images stored in the buffer memory 8 increase in number
(with time), as shown in FIG. 5(c), the bar 22c extends toward the
right side of the frame 22a.
[0027] In this embodiment, when the release button is full-pressed
by the user (Yes in Step S13 to be described below), the still
image data is generated based on the frame image that is based on
the imaging signal output from the imaging sensor 6. Accordingly,
after n frame images are stored in the buffer memory 8 until the
release button is full-pressed by the user from the time at which
the first predetermined time period ends, a process is repeatedly
performed in which the oldest frame image in the buffer memory 8 is
deleted each time the frame image is output, and the output frame
image (the newest frame image) is stored in the buffer memory 8. In
this case, the bar 22c inside the frame 22a does not show any
change as being in the state illustrated in FIG. 5(c). That is, the
bar 22c extends up to the position of the mark 22b that represents
the time (the end of the first predetermined time period and the
beginning of the second predetermined time period) at which the
still image is captured, but does not extend during a period in
which the release button is not full-pressed by the user.
[0028] Next, in the middle of the process in which storage of the
frame image into the buffer memory 8 is repeatedly performed after
the first predetermined time period has elapsed, the control unit 4
determines whether or not the release button is full-pressed by the
user (Step S13). When it is determined that the release button is
full-pressed by the user in Step S13, the control unit 4 determines
that a still image capturing instruction to generate the still
image data is input. In this case, the control unit 4 causes the
second predetermined time period (ending the counting for the first
predetermined time period) to begin to elapse, and causes the bar
22c to extend toward the right side of the frame 22a with time as
illustrated in FIG. 5(d). In this way, by displaying the bar 22c
that indicates where a current time point is between the beginning
and end of the predetermined time period (the second predetermined
time period) on the display unit 12, it is possible to indicate to
the user that the capturing of the slow moving image is not
completed. Next, the control unit 4 acquires information related to
the change in the attitude of the electronic camera 2 relative to
the main subject detected by the detection unit 16, and determines
whether or not the acquired change in the attitude of the
electronic camera 2 is equal to or more than a predetermined
threshold value (Step S14). That is, when it is determined that the
user has full-pressed the release button or the like for example,
it is further determined whether or not the attitude of the
electronic camera 2 which is posed during the image-capturing is
considerably changed, for example, to an attitude of the electronic
camera 2 at the state of not capturing. The predetermined threshold
value is set in advance to an appropriate value and stored in a
memory (not shown) or the like.
[0029] When it is determined that the change in the attitude of the
electronic camera 2 is not equal to or more than the predetermined
threshold value in Step S14 (No in Step S14), the control unit 4
determines whether or not the predetermined time period (the second
predetermined time period) has elapsed (Step S15). That is, it is
determined whether or not the storage of the frame images necessary
to generate the slow moving image data into the buffer memory 8 is
completed after the release button is full-pressed (that is, after
the entering of the still image capturing instruction). When it is
determined that the predetermined time period (the second
predetermined time period) has not yet completely elapsed in Step
S15 (No in Step S15), the control unit 4 returns the process to
Step S14.
[0030] On the other hand, when it is determined that the
predetermined time period (the second predetermined time period)
has completely elapsed in Step S15 (Yes in Step S15), the control
unit 4 determines that the storage of n frame images necessary to
generate the slow moving image data into the buffer memory 8 is
completed, and thereby ends the buffering into the buffer memory 8
and the indication of the current time point by the indicator 22
(Step S16). At this time, as illustrated in FIG. 2(a), n-p (p is a
natural number, n>p) frame images, F2 to F5 . . . , have been
stored in the buffer memory 8 over a period from a time prior to
the input time TS of the still image capturing instruction to a
time prior to the beginning of the first predetermined time period,
and p frame images, . . . Fn and Fn+1, have been stored over a
period from the input time TS of the still image capturing
instruction to the ending time of the second predetermined time
period. In Step S17 described later, the slow moving image data is
generated based on the n frame images F2 to Fn+1. FIG. 5(e)
illustrates the state of the bar 22c inside the frame 22a of the
indicator 22 after the predetermined time period (the second
predetermined time period) has completely elapsed.
[0031] Further, when it is determined that the change in the
attitude of the electronic camera 2 is equal to or more the
predetermined threshold value in Step S14 (Yes in Step S14), the
control unit 4 determines that the attitude of the electronic
camera 2 is considerably changed, and ends the buffering into the
buffer memory 8 and the indication of the current time point by the
indicator 22 even in a case where the predetermined time period
(the second predetermined time period) has not yet elapsed (Step
S16). That is, even in a case where the bar 22c inside the frame
22a of the indicator 22 is not in the state of FIG. 5(e) but in the
state of FIG. 5(d), the time at which it is determined that the
change in the attitude of the electronic camera 2 is equal to or
more than the predetermined threshold value is used as the end
point of the predetermined time period (the second predetermined
time period). In this case, the slow moving image data is generated
in Step S17 based on the frame images stored in the buffer memory
8, where the frame images include n-p (p is a natural number,
n>p) frame images F2 to F5 stored during a period from a time
prior to the input time TS of the still image capturing instruction
to a time prior to the beginning of the first predetermined time
period, and frame images, of which the number is smaller than p,
stored during a period from the input time TS of the still image
capturing instruction to the time at which it is determined that
the change in the attitude of the electronic camera 2 is equal to
or more than the predetermined threshold value, that is, the frame
images F2 to F5 that are smaller in number than n.
[0032] Next, the control unit 4 performs a slow moving image data
generating process and a still image data generating process based
on the plurality of frame images stored in the buffer memory 8
(Step S17). The slow moving image data generating process will be
described first. The control unit 4 reads the frame images F2 to F5
out of the buffer memory 8 at a second frame rate (for example, 24
frames/second or the like which is equal to 1/2.5, that is, 0.4, of
a first frame rate) lower than the first frame rate (for example,
60 frames/second or the like) which is the same as a frame rate
(image-capturing frame rate) at which the frame images are output
from the imaging sensor 6. That is, the frame image F2 stored in
the buffer memory 8 at a time Ti (for example 1/60 second or the
like) as illustrated in FIG. 2(a) is read out of the buffer memory
8 at a time T2 (for example, 1/24 second) as illustrated in FIG.
2(b). Then the read frame images F2 to F5 are subjected to a
resizing process (resizing from a high resolution to a low
resolution) of resizing the frame image to have a resolution
suitable for a moving image, performed by the reduction circuit
(not shown) in the control unit 4, and the moving-image image
process (inclusive of the image compression process), performed by
the moving image signal processing circuit (not shown) in the
control unit 4 so as to generate the slow moving image data. The
value of the second frame rate is set in advance, and stored in a
memory (not shown) in a rewritable manner. Next, the still image
data generating process will be described. The control unit 4 reads
the frame images stored in the buffer memory 8 at the time TS, at
which the still image capturing instruction is input, out of the
buffer memory 8. Next, the still image data is generated by
subjecting the read frame image to the still-image image process
(inclusive of the still image compression process) performed by the
still image signal processing circuit (not shown) provided
separately from the moving image signal processing circuit in the
control unit 4. In this embodiment, since the frame images, each
having pixels more than those required for the standard of HDTV,
that is, high resolution frame images are stored in the buffer
memory 8, it is possible to obtain the still image data of high
resolution. In addition, the number of pixels of the generated
still image data is larger than that of the generated slow moving
image data.
[0033] Next, when an instruction to display the slow moving image
and the still image on the display unit 12 is entered via the
operation unit 14 by the user, the control unit 4 causes the
display unit 12 to display the preview of the slow moving image
that is based on the slow moving image data generated in Step S17.
Then the control unit 4 causes the display unit 12 to display the
preview of the still image that is based on the still image data
generated in Step S17 for several seconds (which are set in
advance) (Step S18).
[0034] Next, the control unit 4 causes the display unit 12 to
display a selection screen that allows the user to select whether
or not to record at least either one of the slow moving image data
and the still image data generated in Step S17 in the recording
medium 10 before recording into the recording medium 10 is started.
The selection screen includes a description informing that one of
the items "record only slow moving image data", "record only still
image data", "record both slow moving image data and still image
data", and "record neither slow moving image data nor still image
data" can be selected, icons, and the like. The control unit 4
determines whether or not the user has selected to record at least
any one of the slow moving image data and the still image data in
the recording medium 10 using the selection screen (Step S19).
[0035] When it is determined that the user has selected to record
at least either one of the slow moving image data and the still
image data in the recording medium 10 in Step S19 (Yes in Step
S19), that is, when any one of the items "record only slow moving
image data", "record only still image data", and "record both slow
moving image data and still image data" is selected by the user,
the control unit 4 records at least any one of the slow moving
image data and the still image data in the recording medium 10
according to the selection by the user (Step S20). Specifically,
when the item "record only slow moving image data" is selected,
only the slow moving image data is recorded (the still image data
is deleted). When the item "record only still image data" is
selected, only the still image data is recorded (the slow moving
image data is deleted). When the item "record both slow moving
image data and still image data" is selected, both of the slow
moving image data and still image data are recorded. In a case
where the slow moving image data is to be recorded in the recording
medium 10, the slow moving image data generated in Step S17 is
subjected to the moving image compression process performed by the
moving image compression circuit (not shown) in the control unit 4
and the compressed slow moving image data is recorded in the
recording medium 10. In a case where the still image data is to be
recorded in the recording medium 10, the still image data generated
in Step S17 is subjected to the still image compression process
performed by the still image signal processing circuit (not shown)
in the control unit 4 and then the compressed still image data is
recorded in the recording medium 10. In a case where both of the
slow moving image data and the still image data are to be recorded
in the recording medium 10, both data are recorded after being
associated with each other (after being added with information
(date and time at which an image is captured, identification
number, or the like) indicating the association between both
data).
[0036] Since the slow moving image data and the still image data
are recorded in association with each other, for example, it is
possible to display information informing that the still image
linked to the slow moving image exists, during the playing of the
slow moving image and to display information informing that the
slow moving image linked to the still image exists, during the
display of the still image. In addition, when displaying a reduced
image (thumbnail image) based on reduction image data of the still
image that is generated at the time of generating the still image
data and recorded in a state of being added to the still image
data, it is possible to display information informing that the
related slow moving image exists. Further, when the user enters an
instruction to play the related slow moving image (or still image)
using the operation unit 14 during the playing of the still image
(or the slow moving image), the slow moving image (or the still
image) can be easily played.
[0037] On the other hand, when it is determined that the user has
selected not to record at least one of the slow moving image data
and the still image data in the recording medium 10 in Step S19 (No
in Step S19), that is, when it is determined that the user has
selected the item "record neither slow moving image data nor still
image data", the control unit 4 deletes both of the slow moving
image data and the still image data generated in Step S17 without
recording them in the recording medium 10 in accordance with the
selection of the user.
[0038] In Step S18, when displaying the selection screen for
selecting whether or not at least any one of the slow moving image
data and the still image data is to be recorded in the recording
medium 10 after the slow moving image and the still image are
displayed for preview on the display unit 12, or after displaying
the selection screen, the invention may employ a structure that can
change the value of the second frame rate and generate the slow
moving image again at the changed second frame rate. This case
effectively applies to a case in which the user wants to further
slow down or slightly increase the playing speed of the slow moving
image which is to be displayed after the user has watched the image
once through the preview. Specifically, the control unit 4 returns
the process to Step S17 when the value of the second frame rate is
changed by the user through the operation of the operation unit 14,
so that a series of frame images stored in the buffer memory 8 is
read again at the changed second frame rate, and the slow moving
image is played based on the frame images that are read. After
that, the slow moving image is displayed on the displayed unit 12
at the changed frame rate for preview, and a confirmation screen
(selection screen) for confirming whether to record the slow moving
image data having the changed frame rate in the recording medium 10
is displayed on the display unit 12. When the user performs an
operation of confirming the record of the changed slow moving image
using the operation unit 14, the slow moving image data generated
with use of the changed second frame rate is recorded in the
recording medium 10.
[0039] According to the electronic camera 2 of the embodiment, it
is possible to capture a slow moving image having an impressive
video effect, high resolution, and extreme precision, and to
capture a still image having high resolution and extreme precision
in the middle of capturing the slow moving image. That is, since
the frame images that constitute a slow moving image are stored
with a high resolution in the buffer memory 8, it is possible to
generate the slow moving image data with high resolution and
extreme precision. In addition, since the still image data is
generated based on the high resolution frame image, it is possible
to generate the still image data with high resolution and extreme
precision (for example, the still image data having a resolution
higher than that of the slow moving image data). Furthermore, since
it is possible to indicate to a user a time period (predetermined
time period) during which the frame images for generating the slow
moving image data are being buffered using the indicator 22, the
user can quickly check whether or not the slow moving image is
being captured. Accordingly, it is possible to suppress a
significant change in the attitude of the electronic camera 2
relative to the subject in the middle of capturing the slow moving
image and thus it is possible to generate the slow moving image
data with good precision. Moreover, it is possible to control the
ending time of the predetermined time period (the second
predetermined time period) based on the detection result from the
detection unit 16, and to suspend the buffering of the frame images
when the attitude of the electronic camera 2 is considerably
changed. Accordingly, it is possible to generate the slow moving
image data with good precision which is obtained before the
attitude of the electronic camera 2 is considerably changed.
[0040] In the above embodiment, when the predetermined time period
(the second predetermined time period) that is set in advance has
elapsed, or when the change in the attitude of the electronic
camera 2 relative to the main subject is equal to or more than the
threshold value, the buffering into the buffer memory 8 and the
indication of the current time point by the indicator 22 end.
However, a configuration may be employed in which the buffering
into the buffer memory 8 and the indication of the current time
point by the indicator 22 end when it is determined that the
release button is full-pressed in a state in which the frame images
are being sequentially stored in the buffer memory 8.
[0041] In the above embodiment, a piece of still image data is
generated based on one frame image stored in the buffer memory 8
when it is determined that the release button is full-pressed, but
two or more pieces of still image data may be generated based on
two or more frame images. Alternatively, the still image data may
be generated based on the frame image stored in the buffer memory 8
before or after it is determined that the release button is
full-pressed. In addition, the still image data may be generated
based on the frame image stored in the buffer memory 8 when the
release button is not full-pressed (for example, in a case where a
best shot is made when the release button is not full-pressed or
the like). In this case, the frame images stored in the buffer
memory 8 are displayed on the display unit 12 for example so that
the user can select at least one frame image to be recorded as the
still image data, and the still image data is generated based on
the selected frame image.
[0042] In the above embodiment, the slow moving image data is
generated by reading, at the second frame rate, the frame images
which are stored at the first frame rate in the buffer memory 8.
However, a configuration may be employed in which the moving image
data is generated by reading the frame images at the first frame
rate and the slow moving image data is generated by adding
information instructing to play back the moving image at the second
frame rate to the generated moving image data.
[0043] In the above embodiment, the frame images F2, . . . , Fn+1
stored in the buffer memory 8 for the time period T1 as illustrated
in FIG. 2(a) are read out of the buffer memory 8 for the time
period T2 in a non-interlace manner as illustrated in FIG. 2(b).
However, the invention may be configured such that the frame images
F2 to Fn+1 may be read in the interlace manner. For example, as
shown in FIG. 6, one field (hereinafter, referred to as a first
field) F2E obtained by diving the frame image F2 into two fields is
read for the time period T1 and then the other field (hereinafter,
referred to as a second field) F2O is read for the time period T1.
The first field F2E is a field configured by only even-numbered
lines of the frame image F2 for example, and the second field F2O
is a field configured by only odd-numbered lines of the frame image
F2. Subsequently, as shown in FIG. 6, after the first field F2E is
read again for the time period T1, one field F3E of the frame image
F3 obtained by diving the frame image F3 into two fields is read
for the time period T1 and then the other field F3O is read for the
time period T1. Through the similar reading operation, that is, as
shown in FIG. 6, a field F4E of the frame image F4 obtained by
diving the frame image F4 into two fields is read, the other field
F4O is read, the field F4E is read again, and a field F5E obtained
by diving the frame image F5 into two fields is read, and the other
field F5O of the frame image is read. In this way, the reading
operation is repeated sequentially for the frame images. As a
result, it is possible to generate the slow moving image data at
the second frame rate that is 1/2.5 (that is, 0.4) of the first
frame rate.
[0044] The above-described embodiment is provided for easy
understanding of the invention and thus is not construed to limit
the invention. Accordingly, each element disclosed in the above
embodiment includes design modifications and equivalents within the
technical scope of the invention.
* * * * *