Digital Camera Patent AbstractA signal recording/reproducing apparatus includes a CCD imager.
The still image taken by said CCD imager is recorded, together with
resolution information, on a recording medium. The recording medium
is recorded, together with resolution information, is a still image
taken by said digital camera and having a higher resolution than
said CCD imager. When a still image is reproduced from said recording
medium and displayed on a monitor, a video encoder converts the
resolution of a reproduced still image based on resolution information.
The converted resolution agrees with a resolution of the monitor.
As a result, a reproduced still image is properly displayed on the
monitor.
Digital Camera Patent ClaimsWhat is claimed is:
1. A digital camera, comprising: an imaging device for subjecting
incident light to photo-electric conversion on an imaging surface
so as to create image data; a recorder for recording the image data
obtained from said imaging device to a removable recording medium
in a manner which conforms with any one of N (N: integer) compatible
modes out of M (M: integer) compatible modes together with management
information indicative of the any one of N (N: integer) compatible
modes; and a reproducer for reproducing the image data in accordance
with any one of the M of compatible modes based on the management
information recorded in said removable recording medium, wherein
the M and N are positive integers satisfying M>N, the M compatible
modes include a compatible mode upper than the N compatible modes,
the image data is motion image data, and the compatible mode is
associated with a frame rate of the motion image data.
2. A digital camera, comprising: an imaging device for subjecting
incident light to photo-electric conversion on an imaging surface
so as to create image data; a recorder for recording the image data
obtained from said imaging device to a removable recording medium
in a manner which conforms with any one of N (N: integer) compatible
modes out of M (M: integer) compatible modes together with management
information indicative of the any one of N (N: integer) compatible
modes; and a reproducer for reproducing the image data in accordance
with any one of the M compatible modes based on the management information
recorded in said removable recording medium, wherein the M and N
are positive integers satisfying M>N, the M compatible modes
include a compatible mode upper than the N compatible modes, the
image data is accompanied by audio data, and the compatible mode
is associated with a sampling rate and a quantifying bit number
of the audio data.
3. A digital camera, comprising: an input processor for subjecting
a signal fetched from outside to an input process corresponding
to any one of N qualities; a recorder for recording a first signal
output from said input processor to a removable recording medium
which stores a second signal having a quality which is different
from any of the N qualities and higher than the N qualities; a reproducer
for reproducing any one of the first signal and the second signal
from said removable recording medium; a quality detector for detecting
a quality of the any one of the first signal and the second signal
reproduced by said reproducer; an output processor for subjecting
the any one of the first signal and the second signal reproduced
by said reproducer to any one of M output processes respectively
corresponding to M qualities; and a selector for activating any
one of the M output processes based on a detection result of said
quality detector, wherein the N and M are positive integers satisfying
N<M, the M qualities include the quality of the second signal,
the first signal and the second signal are motion image data, and
the quality is associated with a frame rate of the motion image
data.
4. A digital camera, comprising: an input processor for subjecting
a signal fetched from outside to an input process corresponding
to any one of N qualities; a recorder for recording a first signal
output from said input processor to a removable recording medium
which stores a second signal having a quality which is different
from any of the N qualities and higher than the N qualities; a reproducer
for reproducing any one of the first signal and the second signal
from said removable recording medium; a quality detector for detecting
a quality of the any one of the first signal and the second signal
reproduced by said reproducer; an output processor for subjecting
the any one of the first signal and the second signal reproduced
by said reproducer to any one of M output processes respectively
corresponding to M qualities; and a selector for activating any
one of the M output processes based on a detection result of said
quality detector, wherein N and M are positive integers satisfying
N<M, the M qualities include the quality of the second signal,
the first signal and the second signal are accompanied by audio
data, and the quality is associated with a sampling rate and a quantifying
bit number of the audio data. Digital Camera Patent DescriptionBACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to digital cameras and, more particularly,
to a digital camera for recording image data onto an unloadably
loaded recording medium, such as a memory card or optical disk,
and reproducing record data out of the recording medium.
2. Description of the Prior Art
The digital cameras have functions of reproducing compressed image
data out of a recording medium and decompressing it into a decompressed
image to be displayed on a monitor provided thereon. Some of the
digital cameras have also a function of reproducing sound data out
of a medium as above and outputting it via a speaker through predetermined
signal processing.
Meanwhile, the parameters associated with the reproduced image
and sound data vary in quality. The individual image sensors are
quite different in respect of the parameter of resolution, e.g.,
pixel count ranges from as low as about 0.35 million to as high
as nearly several hundreds of millions. In order to actually display
reproduced images on a monitor, encoding has to be done so that
the resolution can be matched to the image sensor. In dealing with
motion image data, not only the quality of the resolution parameter
but also the quality of the frame rate parameter should be taken
into consideration. For motion image data, in some cases 15 still
images constitute 1 second of motion image whereas in other cases
30 still images are required for 1 second of motion image. For proper
speed reproduction, reproduction should be suited in frame rate.
Furthermore, for reproducing sound data, the quality associated
with this parameter, which may be expressed in terms of sampling
rate or quantization bit count for conversion from an analog to
digital signal, must be taken into account.
In this manner, the qualities of different digital cameras are
greatly different from one to another in respect of resolution,
frame rate, sound quality, and other parameters. However, as long
as the still image, motion image or sound having been taken by one
person's digital camera is reproduced on that camera, it is satisfactory
to merely have a corresponding reproduce function to a recording
function of the same camera.
However, today's digital cameras employ unloadable recording media,
such as memory cards and magneto-optical disks. It is possible to
commonly utilize only one recording medium between the digital cameras
adopting a same scheme of recording media. This means that one can
use on his or her digital camera a recording medium having been
used on another's digital camera. However, if there is superiority
or inferiority in parameter quality between these cameras, the data
recorded by the digital camera implementing the superior parameter
quality is impossible to reproduce on a digital camera implementing
on inferior parameter quality. More specifically, if one digital
camera has an image sensor with a resolution quality of XGA and
the other digital camera has that of VGA, image data with XGA taken
by the one digital camera cannot be reproduced on the other digital
camera having no XGA-compatible encoding function.
SUMMARY OF THE INVENTION
It is therefore, a primary object of the present invention to provide
a digital camera which can reproduce even an image signal taken
by a superior performance of another digital camera.
A signal recording/reproducing apparatus according to the present
invention, comprises: an input processing circuit for performing
a corresponding input process to any one of qualities of N in kind
on a signal externally fetched; a recorder for recording a first
signal outputted from the input processing circuit to an unloadably
loaded recording medium recorded with a second signal having a quality
different from the qualities of N in kind; a reproducer for reproducing
either one of the first signal or the second signal from the recording
medium; a quality detector for detecting a quality of a signal reproduced
by the reproducer; an output processing circuit for performing output
processing of M in number corresponding to respective qualities
of M in kind on the reproduced signal; and an enabler for enabling
any one of the output processing of M in number based on a result
of detection by the quality detector, wherein the N and the M are
positive integers that satisfy N<M, and the qualities of M in
kind including the quality of the second signal.
According to the present invention, when a signal is externally
given, the input processing circuit performs corresponding input
process to any one of the qualities of N in kind on this signal.
The first signal outputted from the input processing circuit is
recorded on the recording medium by the recorder. The recording
medium herein is unloadably loaded and recorded with a second signal
having a different quality from any of the qualities of N in kind.
If a first signal or second signal is reproduced from the recording
medium by the reproducer, the reproduced signal is supplied to the
output processing circuit for performing corresponding output processing
of M in number to the respective qualities of M in kind. On the
other hand, the reproduced signal is detected in quality by the
quality detector. The enabler enables any one of the output processing
of M in number based on a result of detection by the quality detector.
Consequently, the reproduced signal is output-processed depending
upon its quality, thus being properly outputted. Furthermore, N
and M are positive integers that satisfy N<M, and the qualities
of M in kind include a quality of the second signal. Accordingly,
even when the second signal has a quality that the input processing
circuit is not compatible with, a reproduced signal is properly
outputted. That is, according to the present invention, it is possible
to properly reproduce a signal having been recorded on the recording
medium by an image recording/reproducing apparatus having a higher
performance than the present apparatus.
In one embodiment of the invention, the first and second signals
include respective ones of quality information, and the quality
detector detecting a quality of the reproduced signal according
to the quality information included in the reproduced signal.
In another embodiment of the invention, the input processing circuit
includes an image sensor having a first resolution to shoot a subject,
the first signal being an image signal having the first resolution.
On the other hand, the second signal recorded on the recording medium
is an image signal having a second resolution higher than the first
resolution. In the output processing circuit, a first converter
converts the first resolution image signal into a third resolution
image signal, and a second converter converts the second resolution
image signal into the third resolution image signal. Here, the third
resolution is a resolution of the monitor that is lower than the
first and second resolutions. A converter selector selects either
one of an output of the first converter or an output of the second
converter.
In another embodiment of the invention, the input processing circuit
includes a microphone to intake an external sound and an input processor
to perform signal processing with a first sound quality on a sound
signal taken by the microphone. The first signal is a sound signal
having the first sound quality. On the other hand, the second signal
is a sound signal having a second sound quality superior to the
first sound quality. In the output processing circuit, a first output
processor performs corresponding output processing to the first
sound quality, and a second output processor performs corresponding
output processing to the second sound quality. A processor selector
selects either one of the first output processor or the second output
processor. As a result, a desired sound is outputted
In still another embodiment of the invention, the input processing
circuit includes an image sensor to shoot a subject at a first frame
rate, the first signal being a motion image signal having the first
frame rate. On the other hand, the second signal recorded on the
recording medium is a motion image signal having a different second
frame rate from the first frame rate. The first and second signals
include respective ones of frame rate information, and the reproducer
reproducing either one of the first signal or the second signal
into a form in compliance with the frame rate information. Due to
this, the motion image signal is reproduced at a desired rate.
A digital camera according to the present invention, comprises:
an image sensor for shooting object at a first frame rate; a recorder
for recording a corresponding first motion image signal having the
first frame rate to a subject image shot by the image sensor onto
an unloadably loaded recording medium recorded with a second motion
image signal having a different second frame rate from the first
frame rate; a selector for selecting a desired motion image signal;
a detector for detecting a frame rate of the desired motion image
signal; and a reproducer for reproducing the desired motion image
signal into a form in compliance with the frame rate detected by
the detector.
According to the present invention, a subject is shot by the image
sensor at a first frame rate. A corresponding first image signal
at the first frame rate to the shot subject image is recorded on
the recording medium by the recorder. The recording medium herein
is unloadably loaded and recorded with a second motion image signal
having a different second frame rate from the first frame rate.
If a desired motion image signal is selected by the selector, the
desired motion image signal is detected in frame rate by the detector.
The reproducer reproduces a desired motion image signal in a suited
form for the detected frame rate. That is, the desired motion image
signal is reproduced at normal rate.
In one embodiment of the invention, the first and second motion
image signals include frame rate information, and the detector detecting
a frame rate of the desired motion image signal according to the
frame rate information.
The above described objects and other objects, features, aspects
and advantages of the present invention will become more apparent
from the following detailed description of the present invention
when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing one embodiment of the present
invention;
FIG. 2 is a block diagram showing a configuration of a video encoder;
FIG. 3 is a block diagram showing a configuration of a sound record
processing circuit;
FIG. 4 is a block diagram showing a configuration of a sound reproduce
processing circuit;
FIG. 5 is an illustrative view showing exemplary qualities associated
with typical parameters of a reproduce system;
FIG. 6 is a flowchart showing part of operation of the present
embodiment;
FIG. 7 is a flowchart showing another part of the operation of
the present embodiment;
FIG. 8 is a flowchart showing still another part of the operation
of the present embodiment;
FIG. 9 is a flowchart showing yet another part of the operation
of the present embodiment;
FIG. 10 is a flowchart showing another part of the operation of
the present embodiment;
FIG. 11 is a flowchart showing still another part of the operation
of the present embodiment;
FIG. 12 is a flowchart showing yet another part of the operation
of the present embodiment;
FIG. 13 is a flowchart showing another part of the operation of
the present embodiment; and
FIG. 14 is a flowchart showing still another part of the operation
of the present embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In this embodiment, a magnet-optical disk having a particular diameter
is employed as a recording medium. In order to provide compatibility
between the cameras using the disk as a recording medium, a plurality
of compatible modes are provided which are defined by resolution,
frame rate and sound quality as shown in FIG. 5.
In other words, the digital camera parameters of resolution, frame
rate, and sound quality, each of which vary in parameter quality
as shown in FIG. 5, describe the signals from input processing circuits
and the signals recorded on the magneto-optical disk, and the parameter
qualities of the signals from the input processing circuits are
not always the same parameter qualities of the signals recorded
on the magneto-optical disks. The digital camera of the present
invention has output processing circuits capable of processing signals
recorded on magneto-optical disks which have parameter qualities
that differ from the signals from the input processing circuits.
For resolution, at first, three compatible modes are provided,
i.e. an SXGA mode having pixels in number of 1280.times.960, an
XGA mode having pixels in number of 1024.times.768, and a VGA mode
having pixels in number of 640.times.480.
For motion-image frame rate, two modes are provided, i.e. 30 fps
to form 1 second of motion image with 30 still image frames, and
15 fps to form 1 second of motion image with 15 still image frames.
For sound quality, three modes are provided, i.e. high quality,
normal quality and low quality. In a high quality mode, a stereo
sound is available with a sampling rate of 44 kHz and a quantization
bit count of 16 bits. In a normal mode, a monaural sound is available
with a sampling rate of 22 kHz and a quantization bit count of 16
bits. In a low quality mode, a monaural sound is available with
a sampling rate of 8 kHz and a quantization bit count of 8 bits.
FIG. 1 shows a digital camera of this embodiment. For a recording
system, lowest levels are satisfied among the modes in resolution,
the modes in frame rate and the modes in sound quality. That is,
a CCD imager 1 is such a low-cost imager that outputs an imager
signal of 640.times.480 pixels with a frame rate of 15 fps. Also,
a digital signal processing circuit 5 is such a cheap circuit as
for perfonning signal processing with a low frame rate, e.g. 15
fps. Furthermore, a microphone 17 is a monaural microphone. A sound
recording circuit 18 is also such an inexpensive circuit as for
creating a sound signal with low quality.
In FIG. 1, the CCD imager has a light receiving surface on which
a subject optical image is incident 1 through a lens (not shown).
The CCD imager 1 produces, by photoelectric conversion, a corresponding
imager signal having 640.times.480 pixels to the subject image.
The imager signal is outputted at a frame rate of 15 fps from the
CCD imager 1 in response to a timing signal sent from a timing generator
(TG) 2, and subjected to well-known noise removal and level adjustment
by a CDS/AGC circuit 3, followed by being converted into a digital
signal (imager data) by an A/D converter 4.
A signal processing circuit 5 is arranged in a rear stage of the
A/D converter 4. The signal processing circuit 5, upon given a processing
command from a CPU 19, performs well-known signal processing, such
as color separation and YUV conversion, on the imager data outputted
from the A/D converter 4, thereby creating image data having a luminance
component (Y component) and a chrominance component (U component,
V component) on a pixel-by-pixel basis. The created image data is
delivered via a bus 8 to a memory control circuit 7. The memory
control circuit 7 in turn temporarily store the image data into
an image data storage area 6a of a SDRAM 6. (The CPU 19 includes
a timer 19a and counters 19b and 19c, as will be discussed below.)
A video encoder 9 causes the memory control circuit 7 to read out
the image data in the image data storage area 6a in response to
a processing command sent from the CPU 19. The video encoder 9 fetches
the read-out image data through the bus 8 and encodes it into a
composite image signal of an NTSC format. The encoded composite
image signal is supplied to a monitor 10 mounted on the camera main
body. Herein, the monitor 10 has a screen with a resolution of approximately
0.11 million of pixels. The resolution of the monitor is lower than
that of the CCD imager 1. The video encoder 9 performs conversion
of resolution with the resolution of the monitor 10 taken into consideration.
An image compression/decompression circuit 11, upon receiving a
compression command sent from the CPU 19, fetches 1 frame of image
data out of the image data storage area 6a via the memory control
circuit 7 and the bus 8, to perform image compression on it according
to an JPEG format. Obtaining compressed image data, the image compression/decompression
circuit 11 delivers the compressed image data to the memory control
circuit 7 through the bus 8. The compressed image data is stored
by the memory control circuit 7 onto a compressed data storage area
6b. On the other hand, the image compression/decompression circuit
11, when receiving a decompression command sent from the CPU 19,
causes the memory control circuit 7 to read 1 frame of compressed
image data out of the compressed data storage area 6b, and performs
decompression processing on the read-out compressed image data according
to the JPEG format. Obtaining the decompressed image data, the image
compression/decompression circuit 11 stores the decompressed image
data into the image data storage area 6a through the memory control
circuit 7.
The sound record processing circuit 18, when given a processing
command from the CPU 19, performs record processing on a sound signal
of a predetermined time period that have been corrected by the monaural
microphone 17. More specifically, the sound record processing circuit
18 performs sampling at a sampling rate of 8 kHz on 1/15th of a
second of monaural sound signal outputted from the monaural microphone
17, and then performs quantization by 8 bits into quantized data.
The quantized data is subjected to well-known digital signal processing
to produce low-quality digital sound data. The produced signal sound
data is stored by the memory control circuit 7 into a sound data
storage area 6c.
A sound reproduce processing circuit 15, when given a processing
command from the CPU 19, reads out the sound data stored in the
sound data storage area 6c through the memory control circuit 7.
The sound reproduce processing circuit 15 performs predetermined
reproduce processing on the read-out sound data and outputs the
processed sound signal through a speaker 16.
The CPU 19 also performs by itself to record and reproduce image
and sound data, in addition to issuance of the above-mentioned processing
commands. The CPU 19, upon recording, reads out through the memory
control circuit 7 the compressed image data stored in the compressed
data storage area 6b and the sound data stored in the sound data
storage area 6c, and delivers the compressed image data and sound
data thus read, together with a record command, onto a disk control
circuit 12. The compressed image data and sound data are recorded
onto a magnet-optical disk 14. Meanwhile, the CPU 19, upon reproducing,
issues a reproduce command to the disk control circuit 12 so that
the disk control circuit 12 reads the compressed image data and
sound data out of the magnet-optical disk 14. The CPU 19 writes
through the memory control circuit 7 the read-out compressed image
data and sound data respectively to the compressed data storage
area 6b and the sound data storage area 6c.
Incidentally, the magnet-optical disk 14 is an unloadable recording
medium and accessible, when loaded in a slot 13, by the disk control
circuit 12.
A system controller 26 is connected with an R/P select switch to
select either one of a record mode and a reproduce mode, a record
mode select switch 21 to select either one of still image record
mode or a motion image record mode, a reproduce mode select switch
22 to select either one of a still image reproduce mode and a motion
image reproduce mode, a release button 23 to issuing a trigger for
taking a picture of a subject, a set key 24 to instruct a start
of motion image reproducing in a motion image reproduce mode, and
a renewal key 25 to instruct a renewal of a reproduced still image
in a still image reproduce mode.
When a record mode is selected by the R/P select switch 20, a system
controller 26 supplies the CPU 19 with a key state signal that corresponds
to a status in operation of the record mode select switch 21 and
release button 23. On the other hand, when a reproduce mode is selected
by the R/P select switch 20, the system controller 26 supplies the
CPU 19 with a key state signal that corresponds to a status of the
reproduce mode select switch 22, set key 24 and renewal key 25.
The video encoder 9, in concrete, is configured as shown in FIG.
2. The image data read out of the image data storage area 6a of
the SDRAM 6 is delivered to resolution conversion circuits 9a 9c.
The resolution conversion circuit 9a is to convert a VGA resolution
into a resolution on the monitor 10. The resolution conversion circuit
9b is to convert an SGA resolution into the resolution on the monitor
10. The resolution conversion circuit 9c is to convert an SXGA resolution
into the resolution on the monitor 10. The image data outputted
from the resolution conversion circuits 9a 9c is supplied to a select
circuit 9g through D/A converters 9d 9f. The select circuit 9g selects
any one of image signals outputted from the D/A converters 9d 9f
according to a select instruction sent from the CPU 19. Specifically,
when the input image data has a resolution VGA, the select circuit
9g selects an output of the D/A converter 9d. When the input image
data has a resolution XGA, the select circuit 9g selects an output
of the D/A converter 9e. When the input image data has a resolution
SXGA, the select circuit 9g selects an output of the D/A converter
9f. The image signal thus selected is converted into a composite
video signal by a composite video signal producing circuit 9h. The
composite video signal thus converted is then outputted onto the
monitor 10.
The sound record processing circuit 18 is configured as shown in
FIG. 3. The A/D converter 18a is configured by a sampling circuit
181a to perform sampling on a sound signal at a sampling rate of
8 kHz, and a digitizing circuit 182a to convert the sampled data
into digital data at a quantization bit count of 8 bits. The output
of the digitizing circuit 182a is subjected to well-known signal
processing by the digital signal processing circuit 18b and then
outputted as low-quality digital sound data.
The sound reproduce processing circuit 15 is configured as shown
in FIG. 4. The sound data read out of the sound data storage area
6c of the SDRAM 6 is inputted to a high-quality reproduce system
15a, normal reproduce system 15b and low-quality reproduce system
15c. The high-quality reproduce system 15a is formed by a digital
signal processing circuit for L-side sound 151a, a D/A converte
152a, a digital signal processing circuit 153a for R-side sound
and a D/A converter 154a. The D/A converters 152a and 154a herein
are designed to properly convert high-quality sound data having
been sampled at a sampling rate of 44 kHz and quantized at a quantization
bit count of 16 bits into an analog signal.
The normal reproduce system 15b is formed by a digital signal processing
circuit for monaural sound 151b and a D/A converter 152b. The D/A
converter 152b is designed to convert normal sound data having been
sampled at a sampling rate of 22 kHz and quantized at a quantization
bit count of 16 bits into an analog signal. The low-quality reproduce
system 15calso is formed by a digital signal processing circuit
for monaural sound 151c and a D/A converter 152c. The D/A converter
152c is designed to properly convert low-quality sound data having
been sampled at a sampling rate of 8 kHz and quantized at a quantization
bit count of 8 bits into an analog signal.
The select circuit 15d selects any one of outputs of the high-quality
reproduce system 15a, normal reproduce system 15b and low-quality
reproduce system 15c according to a select instruction sent from
the CPU 19, and outputs it to the speakers 16L and 16R. More specifically,
if the input sound data is high-quality sound data, the select circuit
15d selects L-side and R-side sound signals outputted from the D/A
converters 152a and 154a, and outputs the L-side sound signal to
the speaker 16L and the R-side sound signal to speaker 16R. On the
contrary, when the input sound data is normal sound data, the select
circuit 15d selects a monaural sound signal outputted from the D/A
converter 152b and outputs it to the speakers 16L and 16R. When
the input sound data is low-quality sound data, the select circuit
15d selects a monaural sound signal of from the D/A converter 152c
and outputs it to the speakers 16L and 16R.
Explanation will now be made concretely on an operation of the
CPU 19, with reference to FIG. 6 to FIG. 14. In these figures, FIG.
6 to FIG. 9 show an operation for a case that a record mode is selected,
and FIG. 10 to FIG. 14 show an operation for a case that a produce
mode is selected.
Referring first to FIG. 6, in step S1 through-image display processing
is made. In this case, the TG2 is given a read instruction while
the signal processing circuit 5 and video encoder 9 are respectively
given processing commands. Furthermore, the select circuit 9g of
FIG. 2 is given a command to select an output of the D/A converter
9d. As a result, subject motion images are displayed real-time on
the monitor 10.
The CPU 19 then determines in step S3 whether the release button
23 has been pressed or not. If obtaining a determination result
of ES the process advances to step S5. In step S5 it is determined
whether the record mode currently selected is in a still image record
mode or motion image record mode. If a still image record mode is
selected, the process proceeds to step S7. When a motion image record
mode is selected, the process proceeds to step S9. After completing
the process of the step S7 or S9, the CPU 19 returns to step S1.
In step S7 a subroutine shown in FIG. 7 is processed. First, in
step S11 it is determined whether a predetermined time period has
elapsed or not. If determined "YES", in step S13 a picture-taking
process is suspended. The predetermined time period in step S11
corresponds to a time required for the image data (still image data)
of a subject image upon operating the release button 23 to be processed
through from a signal processing circuit 5 to an output. In step
S13 the TG2 is given a read suspension command, and the signal processing
circuit 5 is given a processing suspension command. Due to this,
after operating the release button 23, only 1 frame of image data
is obtainable.
The CPU 19 subsequently in step S15 provides a compression command
to the image compression/decompression circuit 11. The 1-frame image
data stored in the image data storage area 6a is subjected to JPEG
compression by the image compression/decompression circuit 11. This
produces compressed image data. The compressed image data produced
is stored into the compressed data storage area 6b through the memory
control circuit 7. The image compression/decompression circuit 11,
each time completing a 1-frame compression process, generates a
compression completion signal. In step S17 a presence or absence
of a compression completion signal is determined. If determined
ES in step S19 the compressed image data is read out of the compressed
data storage area 6b. The CPU 19 thereafter in step S21 instructs
the disk control circuit 21 to record the read-out compressed image
data. At this time, the CPU 19 provides resolution information on
"VGA" and a file no., together with a record command,
to the disk control circuit 21. The disk control circuit 12, in
turn, records the compressed image data, together with the resolution
information "VGA" and file no. onto the magnet-optical
disk 14. In the magnet-optical disk 14, a still image file is formed
accommodating the compressed image data and having the resolution
information and the file no. written in a header.
Incidentally, the digital camera in this embodiment produces only
VGA-resolution image data. Accordingly, resolution information "VGA"
is outputted in step S21.
When the still image file has been recorded, the disk control circuit
12 issues a record completion signal. In step S23 ES is determined
in response to the record completion signal. Thereupon, the CPU
19 advances to step S25 to send a processing command to the sound
record processing circuit 18. In response to the processing command,
the sound record processing circuit 18 fetches 1/15th of a second
of a monaural sound signal from the monaural microphone 17, and
converts the fetched sound signal into low-quality sound data. The
converted low-quality sound data is written to the sound data storage
area 6c through the memory control circuit 7. In step S27 it is
determined whether 5 seconds have elapsed from starting the sound
record processing or not. The sound record processing of step S25
is repeated until obtaining a determination result of ES The low-quality
sound data is accumulated to 5 seconds onto the sound data storage
area 6c.
After elapsing by 5 seconds, the CPU 19 advances from step S27
to step S29 to read 5 seconds of audio data out of the audio data
storage area. Furthermore, the CPU 19 in step S32 instructs the
disk control circuit 12 to record the 5-second audio data. This
record instruction includes information of sound quality of "law
quality" and a file no. same as that of the still image file
recorded in step S21. The disk control circuit 12 records onto the
magnet-optical disk 14 asound file that accommodates the 5-second
sound data and written in a header with the sound quality information
and file no. Mutual relation is given through the file no. between
a still image file accommodating the compressed image data produced
responsive to an operation of the release button 23 and a sound
file accommodating the sound data fetched after the operation of
the release button 23.
The disk control circuit 12 also generates a record completion
signal upon completing the sound data recording. When a record completion
signal is generated, the CPU 19 in step S33 determines ES and returns
to step S7 shown in FIG. 6. Thereafter, the CPU 19 returns to step
S1. As a result, motion images are again displayed real-time on
the monitor 10.
In step S9 a subroutine shown in FIG. 9 is executed. First, in
step S41 a time period of 1/15th of a second is set onto the timer
19a, and then the timer 19a is started. Next, in step S43 a completion
command is given to the image compression/decompression circuit
11. In step S45 a processing command is sent to the sound record
processing circuit 18. The image compression/decompression circuit
11 reads image data out of the image data storage area 6a and performs
JPEG compression on it into compressed image data, and writes the
compressed image data to the compressed data storage area 6b. Meanwhile,
the sound processing circuit 18 converts the 1/15th of second of
sound signal inputted through the microphone 17 into low-quality
sound data, and writes the converted low-quality sound data to the
sound data storage area 6c.
In step S47 it is determined whether the release button 23 has
been shifted off or not, and in step S49 it is determined whether
the timer 19a has reached time-up or not. If the timer reaches time-up
in a state the release button 23 is being pressed, the process returns
to step S41 to repeat the above process. Due to this, until the
release button 23 is released from the pressing state, a plurality
of frames of compressed image data are successively accumulated
onto the compressed data area 6b. Simultaneously, the related sound
data to the compressed image data is accumulated to the sound data
area 6c.
If the release button 23 is shifted off, then in step S51 compressed
image data and low-quality sound data are read out respectively
of the compressed data area 6b and the sound data area 6c. In step
S53, the disk control circuit 12 is instructed to record these of
data. At this time, the CPU 19 supplies resolution information of
"VGA", sound quality information of "low quality",
frame rate information of "15 fps" and a file no., together
with a record command, to the disk control circuit 12. Due to this,
the disk control circuit 12 forms in the magnet-optical disk 14
a motion image file that accommodates compressed image data and
low-quality sound data and is written in a header with resolution
information, sound quality information, frame rate information and
a file no. This motion image file is prepared in an AVI (Audio Video
Interleave) form or QUICKTIME form.
The disk control circuit 12, when the recording is completed, outputs
a record completion signal. In response to this record completion
signal, the CPU 19 returns from step S55 to step S9 shown in FIG.
6. The CPU 19 thereafter returns to step S1. As a result, real time
motion images are again displayed on the monitor 10.
When a reproduce mode is selected, the CPU 19 first in step S61
of FIG. 10 determines whether either one is selected of a still
image reproduce mode or a motion image reproduce mode. If a still
image reproduce mode is selected, in step S63 a still image reproduce
process is carried out. If a motion image reproduce mode is selected,
in step S65 a motion image produce process is carried out. After
ending the process of step S63 or S65, the process returns to step
S61.
In a still image reproducing mode, a subroutine shown in FIG. 11
is executed. The CPU 19 first in step S71 sets a count value S of
the counter 19b to "1", and then in step S73 instructs
the disk control circuit 12 to reproduce a still image file S and
sound file S. After reproducing a still image file S and sound file
S, the CPU 19 in step S75 writes the compressed image data and sound
data contained in these files, respectively, to the compressed data
storage area 6b and the sound data storage area 6c. In step S77
resolution information is detected from the still image file S while
sound quality information is from the sound file S.
In step S79, any one of the resolution conversion circuits 9a-9c
of FIG. 2 is selected based on the detected resolution information.
Specifically, when the resolution information is "VGA",
the gselect circuit 9g is instructed to select an output of the
D/A converter 9d. When the resolution information is "XGA",
the select circuit 9g is instructed to select an output of the D/A
converter 9e. When the resolution information is "SXGA",
the select circuit 9g is instructed to select an output of the D/A
converter 9f.
In the succeeding step S81, any one of the reproduce systems 15a-15c
of FIG. 4 is selected based on the detected sound quality information.
That is, when the sound quality information is "high quality",
the select circuit 15d is instructed to select outputs of the D/A
converters 152a and 154a. When the sound quality information is
"normal", the select circuit 15d is instructed to select
an output of the DIA converter 152b. When the sound quality information
is "low quality", the select circuit 15d is instructed
to select an output of the D/A converter 152c.
The magnet-optical disk 14 is unloadably loaded. There is a case
that an XGA-resolution still image and high-quality sound have been
taken on another digital camera are recorded to the magneto-optical
disk 14. In such a case, it is impossible for the GVA resolution
conversion circuit 9a to properly process image data with XGA resolution.
Similarly, the low-quality reproduce system 15c cannot properly
process high-quality sound data. In order to cope with this, this
embodiment is further provided with an XGA-resolution conversion
circuit 9b, an SXGA-resolution conversion circuit 9c, a high-quality
reproduce system 15a and a normal reproduce system 15b. This makes
it possible to properly reproduce image data having a higher resolution
than the CCD imager 1 and sound data processed by a higher performance
processing circuit than the sound record processing circuit 18.
The CPU 19 subsequently in step S83 sends an decompression command
to the image compressed/decompression circuit 11, and in step S85
starts up the video encoder 9. In response to the decompression
instruction, the image compression/decompression circuit 11 reads
out compressed image data, and performs JPEG decompression on the
read-out compressed image data. The decompressed image data is stored
to the image data storage area 6a. The video encoder 9 reads out
the image data stored in the image data storage area 6a to display
a reproduced still image on the monitor 10. Because the compatible
resolution conversion circuit with the image data is selected in
step S79, the reproduced still image is properly displayed on the
monitor 10.
The CPU 19 subsequently sends a processing command to the sound
reproduce processing circuit 15. Thereupon, the sound reproduce
processing circuit 15 reads 1/15th of a second of sound data out
of the sound data storage area 6c, and outputs a corresponding sound
to the read-out sound data through the speaker 16. In this case,
the sound data has been processed by the reproduce system selected
in step S81. Accordingly, sound is properly outputted through the
speaker 16.
In step S89 it is determined whether a time period of 5 seconds
has elapsed from a sound reproduction start or not. The process
of step S87 is repeated until obtaining a determination result of
ES As a result, continuous reproduction is made of 5 seconds of
sound data stored in the sound data storage area 6c. If the time
period of 5 seconds has elapsed and ES determination is made in
step S89, the CPU 19 determines in respective steps S91 and S93
whether the renewal key 25 and the reproduce mode select switch
22 have been respectively operated or not. If the renewal key 25
is pressed, in step S95 the counter 19b is incremented and in step
S97 the video encoder 9 is stopped, and the process returns to step
S73. On the other hand, if the reproduce mode select switch 22 is
operated, the process directly returns to step S63 shown in FIG.
10.
In a motion image reproduce mode, a subroutine shown in FIG. 13
and FIG. 14 is executed. First in step S101 an image file select
process is performed. If a desired motion image file is selected,
in step S103 the disk control circuit 12 is instructed to reproduce
the selected motion image file. In the succeeding step S105 the
compressed image data and sound data contained in the reproduced
motion image file are written through the memory control circuit
7, respectively, onto the compressed data storage area 6b and the
sound data storage area 6c. After ending the writing, the process
advances to step S107 to detect resolution information, sound quality
information and frame rate information contained in the reproduced
motion image file.
In step S109 any one is selected of resolution conversion circuits
9a-9c shown in FIG. 2 based on the detected resolution information.
In step S111 any one is selected of the high-quality reproduce system
15a, the normal reproduce system 15b and the low-quality reproduce
system 15c shown in FIG. 4 based on the detected sound quality information.
For example, in the case that the resolution information represents
"VGA" and the sound quality information shows "normal
quality", the select circuit 9g of FIG. 2 in step S109 is given
a command to select the D/A converter 9d, and in step S111 the select
circuit 15d of FIG. 4 is given a command to select the D/A converter
152b.
In step S113 a count value M of the counter 19c is set to "1".
In the succeeding steps S115 and S117, it is determined on a presence
or absence of operation in the set key 24 and the reproduce mode
select switch 22. If the set key is pressed, the process proceeds
to step S119. If the reproduce mode select switch 22 is operated,
the process returns to step S65 of FIG. 10.
In the case the process advances to step S119, the CPU 19 in this
step starts up the video encoder 9, and in step S121 sets a corresponding
time period to the detected frame rate information onto the timer
19a. For example, if the detected frame rate information is "30
fps", then 1/30 of a second is set onto the timer 19a. Completing
the setting, the timer 19a is started in step S123, and thereafter
in respective steps S125 and S127 the image compression/decompression
circuit 11 and the sound reproduce processing circuit 15 are respectively
given a decompression command and a processing command. The image
compressed/decompression circuit 11, each time given a decompression
command, reads 1 frame of compressed image data out of the compressed
data area 6b and performs JPEG decompression thereon. The produced
compressed image data is written to the image data area 6a. This
decompressed image data is read out by the video encoder 9 and subjected
to a resolution conversion process by the resolution conversion
circuit having been selected in step S79. As a result, still image
in a current frame is properly displayed on the monitor 10.
On the other hand, the sound reproduced processing circuit 15,
each time given a processing command, reads a corresponding time
period of sound data to 1 frame out of the sound data area 6c. The
read-out sound data is subjected to reproduce processing by the
reproduce system having been selected in step S111. As a result,
sound is properly outputted through the speaker 16. Incidentally,
the CPU 19 sends the detected frame rate information, together with
a processing command, to the sound reproduce processing circuit
15. The sound reproduce processing circuit 15 in turn reads a corresponding
time period of sound data to the 1 frame based on this detected
frame rate information.
In step S129 it is determined whether the timer 19a has reached
time-up or not. If when obtaining a determination result of ES the
process advances to step S133 through a counter 19c increment process.
In step S133 the current count value M is compared with the number
of frames M max of the compressed image data contained in the motion
image file, and the process of steps S121 (S133 is repeated until
M>Mmax is reached. If reaching M>Mmax, in step S135 a video
encoder 9 is stopped and the process returns to step S101.
By the process of steps S121-S133, the compressed image data in
each frame and sound data corresponding to 1 frame are reproduced
in the order according to a time on the timer 19a. As a result,
motion images are displayed varying at normal speed while sounds
are outputted through the speaker 16 at normal speed.
As described above, the digital camera of this embodiment adopts
the low quality CCD imager, signal processing circuit, microphone
and sound record processing circuit, and can cope with only the
lowest level of the compatible mode of FIG. 5. In contrast, the
reproduce system is structured to satisfy all the compatible modes
of FIG. 5. Accordingly, where a high-resolution image or high-quality
sound taken on another digital camera is recorded on the magneto-optical
disk 14, such an image and sound is possible to properly reproduce
on the digital camera of the present embodiment.
Incidentally, in this embodiment the compatible modes were explained
limited in resolution, frame rate and sound quality to those as
shown in FIG. 5. However, the invention is never limited to them.
That is, the compatible modes may be defined as two modes, i.e.
an image compression mode to compress still image data according
to a JPEG format and a non-compression mode not to perform any compression
process at all.
Also, the motion image file in this embodiment was to be prepared
in an AVI form or QUICKTIME form, the motion image file may be in
an MPEG scheme.
Furthermore, the digital camera was provided with the processing
circuits to cope with the lowest level of compatible modes. Alternatively,
the digital camera may provided with a medium level or highest level
of processing circuits, instead of the lowest level. It is possible
to provide in the digital camera processing circuits to cope with
two of the three levels. For example, it is possible to adopt a
CCD imager shootable with XGA resolution in addition to VGA resolution
thereby enabling recording an image with the lowest or medium level
resolution, or to adopt a signal record processing circuit to perform
sound processing with low and high two qualities thereby enabling
low-quality or high-quality sound data creation.
Also, although the embodiment used the magnet-optical disk as recording
medium, it is needless to say that a recording medium, such as a
memory card, may be employed provided that it can be unloadably
loaded onto the camera main body.
Furthermore, although the embodiment had a plurality of resolution
conversion circuits in the video encoder to select a corresponding
resolution conversion circuit to the resolution of reproduced image
data, the resolution conversion circuit on the video encoder maybe
one in number so that parameters set on the circuit are variable
depending upon resolution of reproduced image data. By doing so,
it is possible to cope with a plurality of resolutions by use of
one resolution conversion circuit. Also, although the sound data
reproduce systems were prepared in plurality of number depending
on the quality, a plurality of qualities can be dealt with by one
reproduce system if varying the processing parameters each time
reproduction is done.
Also, an image is displayed on the monitor simultaneous with turning
on a power to the camera. It is however needless to say that a monitor
on/off switch may be provided to display an image depending upon
selection by an operator.
Although the present invention has been described and illustrated
in detail, it is clearly understood that the same is by way of illustration
and example only and is not to be taken by way of limitation, the
spirit and scope of the present invention being limited only by
the terms of the appended claims.
|