JP2001111958A - Electronic still camera - Google Patents

Abstract

(57) [Summary] [Problem] To record a very large number of images at low cost and to enable recording and playback of images close to moving images.
It is possible to shoot without worrying about the recording state of the image or the remaining capacity of the memory. SOLUTION: An image sensor 1 and a photographing mode switch 15 are provided.
Operating means such as an audio recording switch 25, an image compression / expansion circuit 6 for compressing / expanding image data, a high-speed RAM 11 for storing a plurality of compressed image data, and a magneto-optical disk 14 for recording compressed image data. Image compression / decompression circuit 6
And a CPU 10 for controlling compression in the RAM, writing / reading of the RAM 11 and recording of the magneto-optical disk 14,
U10 is an image compression / decompression circuit 6 according to the operation of the operation means.
, And control is performed to terminate the compression in response to the release of the operation of the operating means.
Control is performed such that a plurality of pieces of image information stored in the AM 11 are recorded on the disk 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an electronic still camera for recording an image signal of a still image obtained by imaging with an image sensor on a recording medium.

[0002]

2. Description of the Related Art Conventionally, an electronic still camera uses a magnetic disk such as a floppy disk having a diameter of about 2 inches, a memory card, or the like as a recording medium, and can record a color still image on the recording medium. It has been done.

The number of revolutions for recording and reproducing data on the floppy disk having a diameter of about 2 inches is 3600 rpm.
(A case corresponding to the so-called NTSC system of the television broadcasting system), in which one rotation is used to record one field. When recording is performed in frame units, 25 screens can be recorded per disc, and when recording is performed in field units, 50 screens can be recorded per disc.

The memory card has a total memory capacity of, for example, several megabytes, and can record, for example, about several tens of still images.

[0005]

The above-mentioned conventional electronic still camera has the following problems.

First, when the above-mentioned floppy disk having a diameter of about 2 inches is used as a recording medium, the disk has a size of 2 frames per disk as described above.
Only about 50 images can be recorded on a 5-screen, field-by-field basis.

In addition, when the above-mentioned memory card is used, the memory card is still expensive (currently, about tens of thousands of yen), and the storage capacity is about several megabytes instead of being expensive. Due to the above restrictions, only tens of still images can be stored, and continuous shooting of several frames per second can record only tens of seconds. Therefore,
Due to these problems, when using the memory card,
It is not easy to shoot and record one after another.

Further, the above-mentioned magnetic disk,
Any of those using a memory card can perform continuous shooting, but can record images close to moving images (hereinafter referred to as pseudo moving images),
There is no playback function.

In addition, the conventional electronic still camera has a drawback that the waiting time for recording the photographed image on a magnetic disk or the like is long, and the photographing must be performed while paying attention to the recording state of the image on the magnetic disk. Similarly, the conventional electronic still camera has a drawback in that it is necessary to take a picture while paying attention to the capacity of a memory card having a small storage capacity.

In view of the above, the present invention is capable of recording a very large number of images at low cost and recording and reproducing images close to moving images. It is an object of the present invention to provide an electronic still camera capable of shooting without worrying about the remaining capacity of the memory.

[0011]

An electronic still camera according to the present invention has been proposed to achieve the above-mentioned object, and converts an image formed on an imaging surface into an electric signal to obtain image information. Imaging means, operating means, image compression means for compressing the image information, semiconductor memory means for temporarily storing a plurality of compressed image information, and a large-capacity recording the compressed image information. A recording medium, at least compression of the image compression means and writing / writing of the semiconductor memory means;
Control means for controlling reading and recording of the recording medium, wherein the control means starts compression by the image compression means in response to operation of the operation means, and responds to release of operation of the operation means Controlling to terminate the compression by the image compression means, and performing control to record a plurality of pieces of image information stored in the semiconductor memory means on the recording medium after the compression by the image compression means is completed. It is a feature.

An electronic still camera according to the present invention has been proposed in order to achieve the above-mentioned object, and an image pickup means for converting an image formed on an image pickup surface into an electric signal to obtain image information. Operating means, image compression means for compressing the image information, semiconductor memory means for temporarily storing a plurality of compressed image information, a large-capacity recording medium for recording the compressed image information, At least control means for controlling compression of the image compression means, writing / reading of the semiconductor memory means, and recording on the recording medium, wherein the control means operates in response to an operation of the operation means. After the compression by the image compression means is started, the remaining capacity of the semiconductor memory means is detected, and when it is detected that the remaining capacity has been exhausted, the compression by the image compression means is terminated and stored in the semiconductor memory means. A plurality of image information is characterized in performing control to record on the recording medium.

Here, a predetermined disk (for example, a magneto-optical disk) can be used as the large-capacity recording medium. In addition, the plurality of shooting modes include, at least, a still image mode for recording a still image on the recording medium, a continuous shooting mode for recording a continuous still image on the recording medium, and a continuous shooting mode close to a moving image. Examples include a pseudo moving image mode for recording on a recording medium, and an audio recording mode for recording only audio on the recording medium. Further, the electronic still camera of the present invention may be provided with an image decompression means for decompressing the compressed image information, a display means for displaying the image information, and the like.

Further, the electronic still camera of the present invention includes:
Voice information input means for inputting voice information and voice compression means for compressing voice information can be provided. At this time, the semiconductor memory means can also temporarily store the compressed voice information, The capacity recording medium can also record the compressed audio information. At this time, the electronic still camera of the present invention can also be provided with audio decompression means for decompressing the compressed audio information.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a configuration of an electronic still camera according to an embodiment of the present invention.

The electronic still camera according to the present embodiment has the structure shown in FIG.
As shown in FIG. 1, an image pickup device 1 that converts an image formed on an image pickup surface into an electric signal to be image information, operation means such as a photographing mode switch 15 and a voice recording switch 25, and digitally converted image data Image compression / expansion circuit 6 for compressing / expanding image data, a high-speed RAM (random access memory) 11 which is a semiconductor memory means for temporarily storing a plurality of compressed image data, and record the compressed image data. Disk 14 as a large-capacity recording medium
And a CPU (Central Processing Unit) 10 as control means for controlling at least the compression in the image compression / expansion circuit 6, the writing / reading of the RAM 11, and the recording of the magneto-optical disk 14. In response to the operation of the operating means, the image compression / expansion circuit 6 starts compression, and in response to the release of the operation means, controls the image compression / expansion circuit 6 to end the compression. After the compression by the compression / expansion circuit 6 is completed, control is performed so that a plurality of pieces of image information stored in the RAM 11 are recorded on the magneto-optical disk 14.

Further, the CPU 10 of the electronic still camera according to the present embodiment starts the compression by the image compression / expansion circuit 6 in response to the operation of the operation means, and then starts the RAM.
When the remaining capacity is detected and the remaining capacity is detected to be exhausted, the compression by the image compression / expansion circuit 6 is terminated, and a plurality of pieces of image information stored in the RAM 11 are recorded on the magneto-optical disk 14. Perform control.

In FIG. 1, an image of a subject or the like is formed on an image pickup surface of an image pickup device 1 such as a CCD (charge-coupled device) by a lens system (not shown). The image sensor 1 is driven by a driver 2, and an image output from the image sensor 1 is converted into digital data by an A / D (analog / digital) converter 3. The digital image data is subjected to signal processing such as so-called knee and gamma processing by the signal processing circuit 4 and then temporarily stored in the buffer memory 5.

The image data stored in the buffer memory 5 is read out and sent to the compression section of the image compression / decompression circuit 6, where, for example, the so-called JPEG (International Standardization Working Group for color still image coding) is used. Joint Pictu
The compression encoding is performed by using an algorithm of a "re Expert Group" method. Therefore, as a specific configuration of the compression unit of the image compression / decompression circuit 6, an orthogonal transform circuit that performs a discrete cosine transform (DCT) on the image data, and a quantization that quantizes a DCT coefficient by the discrete cosine transform And a coder for performing entropy coding such as Huffman coding on the quantized output. Note that arithmetic coding may be used as entropy coding. From the image compression / expansion circuit 6, data obtained by adding header information to the image data compressed by the compression processing is output.
After being stored in a high-speed RAM (random access memory) 11, it is recorded via a disk driver 13 on a magneto-optical disk 14, which is a large-capacity recording medium.

On the other hand, one of the audio signal subjected to the acoustic-electric conversion by the microphone 17 and the audio signal via the audio line input terminal 18 is selected by the switch 19 and sent to the amplifier 20. The audio signal amplified by the amplifier 20 is converted into digital audio data by an A / D converter 21 and the audio compression / decompression circuit 2
Sent to 2.

In the compression section of the audio compression / expansion circuit 22,
For example, the audio signal is time-compressed to 640 times in the standard mode and 1280 times in the long-time mode. The audio compression / expansion circuit 22 specifically has a memory such as a RAM.
The above-described time compression and time expansion are realized by changing the write / read speed of the memory.

The audio compression / expansion circuit 22 divides an audio signal or the like into a plurality of frequency bands so that the higher the frequency band, the wider the bandwidth, and separates the signals in each frequency band into fixed sections (blocks). A cosine transform (DCT) process is performed, and the obtained coefficient data is further divided into each critical band in consideration of human auditory characteristics, and compression codes are adaptively allocated to each critical band in consideration of a so-called masking effect. ATRAC (Adaptive TRansform)
Acoustic signals can also be compressed by a compression coding technique called an Acoustic Coding method.
As a configuration for performing the compression encoding in consideration of the human auditory characteristics, a filter means for dividing an input audio signal into a rough frequency band in consideration of a critical band, and an output of the filter means for each predetermined block unit Orthogonal transform means for performing DCT transform on the input signal; and adaptive bit assigning means for obtaining adaptive bit assignment information in consideration of the masking effect in a critical bandwidth according to human auditory characteristics using an output of the orthogonal transform means. It is possible to use an encoding means for encoding the output of the orthogonal transform means based on the bit assignment information obtained by the adaptive bit assignment means.

The audio data compressed by the compression unit of the audio compression / expansion circuit 22 as described above is transmitted to the high-speed RA via a bus.
After being stored in an M (random access memory) 11 via a disk driver 13
4 is recorded.

For this reason, according to the electronic still camera of the present embodiment, the audio data and the image data are both recorded on the magneto-optical disk 14 or the image data is recorded without recording the audio data. Only to do,
It is also possible to record only audio data without recording image data. Note that whether to record audio data is instructed by an audio recording switch 25 described later.

In this embodiment, the magneto-optical disk 14 is a very inexpensive and large-capacity (140 megabytes, for example, at present, about 1,000 yen) rewritable optical disk. I have. In particular,
A recording medium called a so-called mini-disc (MD: Mini Disc), which is a magneto-optical disc having a diameter of 64 mm, is used. The compressed image data and the compressed audio data are recorded on the magneto-optical disc 14. Is recorded and played back.

For this reason, the compressed image data from the image compression / decompression circuit 6 is added with an error correction code by, for example, a CPU (Central Processing Unit) 10 and further subjected to, for example, EFM (8-14 modulation). After that, it is recorded on the magneto-optical disk 14. When the MD is used for the magneto-optical disk 14, an image (one frame or one field) is recorded on the disk in cluster units. The MD cluster is 64 Kbytes,
Therefore, 64 kbytes or 128 kbytes, ...
・ Record one image.

On the other hand, when recording audio data on the magneto-optical disk 14, the CPU 10 also adds an error correction code and EFM modulation to the audio data compressed by the audio compression / expansion circuit 22. It will be recorded after application. The magneto-optical disk 14 compresses, for example, audio for about 10 seconds per field,
Record. The image and the sound are recorded on another track on the magneto-optical disk 14. For example, sound is recorded on the inner track of the magneto-optical disk 14, and image is recorded on the outer track. In this way, by separately setting the recording area for the sound and the image, the recording of the sound becomes easy in the case of after-recording described later.

The disk driver 1 according to the present embodiment
3 irradiates a laser beam to the magneto-optical disk 14, receives reflected light from the magneto-optical disk 14 with a photodetector, and controls rotation of a spindle motor and an optical pickup based on a detection signal from the photodetector. Of the posture of the vehicle. Thus, the disk driver 13 causes the laser light to follow the track on the magneto-optical disk 14 at a constant speed. Here, the disk driver 13 controls the optical pickup and the magnetic field generator at the same time, thereby
4 is recorded. In general, when recording on a magneto-optical disk, there are two types of control: a direct current signal to the magnetic field generator and a modulation signal to the optical pickup, and a modulation signal to the magnetic field generator and a modulation signal to the optical pickup. There is a magnetic field modulation method for providing a DC signal (to make the laser power constant). In the present embodiment, the above-described magnetic field modulation method is employed.

More specifically, the disk driver 13 has a two-axis actuator, a spindle motor, and a thread motor as movable parts, and the two-axis actuator moves the objective lens perpendicular to the magneto-optical disk 14. It has a focusing coil and a tracking coil that moves in the radial direction of the disk 14. The optical pickup includes a laser light source such as a laser diode, a collimator lens, an objective lens, optical components such as a polarizing beam splitter and a cylindrical lens, and a photodetector having a light receiving section having a predetermined pattern. The laser beam from the laser diode is used for reading the magnetization direction of the disk 14 for reading and for servo, and for recording, for raising the temperature of the recording surface of the disk 14 above the Curie point and for servo during recording. Will be The detection signal of the photodetector is
Track king and focus servo, disk 14
This is used to detect the magnetization direction of the signal recorded in (i.e., read the recorded signal). Further, a magnetic field modulation coil (that is, a magnetic field generator) provided for performing the magnetic field modulation is provided on the recording surface of the disk 14 whose temperature has been raised to the Curie point or higher by the laser diode, and a modulated magnetic field corresponding to the EFM signal. Used to give.

When the MD is used as the magneto-optical disk 14, the data transfer rate of the MD is about 140 kbytes / sec. Therefore, even if a single still image is compressed to, for example, 64 Kbytes, it is necessary to record about one .0 image on a disk.
That would take 5 seconds. Therefore, for example, in a continuous shooting mode described later, if image data is directly recorded on the MD, only about two images can be recorded per second. If the compression rate is increased to, for example, 32 Kbytes per image, about 4 images (frames) can be recorded per second, but increasing the compression rate leads to a decrease in image quality. For this reason, in the electronic still camera of the present embodiment, the RAM 11 is provided in order to cover the slow transfer rate of the MD. In other words, the RAM 11 stores the FIFO (first-in-
You can think of it as a first-out memory.

Next, reproduction of the image data and audio data stored in the RAM 11 is performed based on the read address from the CPU 10. When reproducing the image data recorded on the magneto-optical disk 14, the disk driver 13 controls the magneto-optical disk 14.
Is read from the memory.

The compressed image data and audio data read from the magneto-optical disk 14 are temporarily stored in the RAM 11.
The EFM is demodulated and error-corrected by the CPU 10 and then sent to the corresponding image compression / expansion circuit 6 or audio compression / expansion circuit 22 via the bus.

The compressed image data sent to the image compression / expansion circuit 6 is subjected to an expansion process, which is the reverse of the compression process, by an expansion unit of the compression / expansion circuit 6, and then stored in a buffer memory. 5 to the signal processing circuit 7. In the signal processing circuit 7, the buffer memory 5
Is converted into image data that can be displayed on the monitor device 9. That is, when the monitor device 9 uses a liquid crystal display (LCD) or a cathode ray tube (CRT) as a display screen, processing corresponding to these is performed. The image data from the signal processing circuit 7 is converted into an analog image signal by a digital / analog (D / A) converter 8 and sent to the monitor device 9 for display. In the monitor device 9, not only the image data stored in the RAM 11 and the magneto-optical disk 14, but also the image is captured by the image sensor 1 and stored in the buffer memory 5 via the A / D converter 3 and the signal processing circuit 4. It is also possible to display the image data obtained via the signal processing circuit 7 and the D / A converter 8 by directly reading the data thus obtained.

On the other hand, the compressed audio data sent to the audio compression / expansion circuit 22 is
The decompression unit performs a decompression process that is the reverse of the compression process. The expanded audio data is D
The audio signal is converted into an analog audio signal by the / A converter 23, amplified by the amplifier 24, and then output from the audio output terminal 25.

The CPU 10 is a microcomputer for controlling each unit in addition to the above-described processing, and controls the image compression / expansion circuit 6, the audio compression / expansion circuit 22, the disk driver 13, and the like. Further, the CPU 10 also performs opening / closing and opening / closing time control of the optical system based on ON / OFF of a shutter button 16 of the electronic still camera, aperture control, and the like, and a shooting mode for switching a shooting mode described later. A switch signal from the switch 15, a voice recording switch 25 for instructing whether or not to record voice, a microphone 1
The processing of the audio signal processing system and the like is also performed according to a switching signal from the switch 19 for switching whether to record either the audio signal from the audio signal 7 or the audio signal from the audio line input terminal.

Next, the operation of the electronic still camera according to the present embodiment will be described with reference to the following flowchart.

First, the flow chart of FIG. 2 shows the switching between the still image mode, the continuous shooting mode, the pseudo moving image mode, and the after-recording mode by the photographing mode switch 15 and the operation in the after-recording mode.

In the flowchart of FIG. 2, in step S1, it is determined whether or not the photographing mode switch 15 has been turned on. That is, the operation of the electronic still camera of the present embodiment differs depending on the mode set by the shooting mode switch 15,
If it is determined that the shooting mode switch 15 is not turned on, the determination in step S1 is repeated, and if it is determined that the shooting mode switch 15 is turned on, the process proceeds to step S2.

In step S2, it is determined whether or not the still image mode is selected by the photographing mode switch 15, and if it is determined that the still image mode is selected, step S20 is performed.
Proceed to step S.
Proceed to 3. The processing after step S20 will be described later.

In step S3, it is determined whether or not the continuous shooting mode has been selected by the shooting mode switch 15. If it is determined that the continuous shooting mode has been selected, step S40.
Proceed to step S.
Proceed to 4. The processing after step S40 will be described later.

In step S4, it is determined whether or not the pseudo moving image mode has been selected by the photographing mode switch 15. If it is determined that the pseudo moving image mode has been selected, the process proceeds to step S70, in which it is determined that the moving image mode has not been selected. If so, the process proceeds to step S5. The processing after step S70 will be described later.

In step S5, it is determined whether or not the after-recording mode is selected by the photographing mode switch 15. If it is determined that the after-recording mode is selected, step S5 is performed.
The process proceeds to step S6, and if it is determined that no item is selected, the process returns to step S2. If it is determined in step S5 that the post-recording mode is not selected, the process may return to step S1.

Here, the post-recording mode is a mode in which a sound input from the microphone 17 or the sound line input terminal 18 is recorded on the magneto-optical disk 14 irrespective of an image. In step S6 when it is determined that the post-recording mode is selected in step S5, it is determined whether or not the voice recording switch 25 is turned on. When it is determined that the voice recording switch 25 is not turned on, the process of step S6 is performed. Is repeated, and if it is determined that the switch is turned on, step S
Go to 7.

In step S7, the audio compression / expansion circuit 22 starts audio compression processing, and the next step S8
Then, recording of the compressed audio data on the magneto-optical disk 14 via the RAM 11 is started. After step S8, it is determined in step S9 whether or not the voice recording switch 25 has been turned off. If it is determined that the voice recording switch 25 has not been turned off, the determination in step S9 is repeated.
If it is determined that the switch has been turned off, the process proceeds to step S10.

In step S10, the audio compression processing in the audio compression / expansion circuit 22 is terminated. Thereafter, in step S11, recording on the magneto-optical disk 14 is also terminated.

Next, in step S2 of FIG.
In step S20 when the still image mode is selected,
The processing of the flowcharts of FIGS. 3 and 4 is performed. When the still image mode is selected, every time the shutter button 16 is pressed, compression coding of image information and recording of the compression-coded image data on the magneto-optical disk 14 via the RAM 11 are performed. Will be That is, in the still image mode, only one image data is stored in the RAM 1.
The compressed data from the RAM 11 is recorded on the magneto-optical disk 14.

In the flowchart of FIG.
When the process proceeds from step S2 to step S20, the process in the still image mode is started in step S21. When the process in the still image mode is started, it is determined in step S22 whether or not the shutter button 16 has been turned on. If it is determined that the shutter button 16 has not been turned on, the process proceeds to step S22.
Is repeated, and if it is determined that the switch is turned on, the process proceeds to step S23.

In the step S23, an image freeze process is performed to inhibit the image data sequentially sent from the image pickup device 1 through the signal processing circuit 4 from being newly taken into the buffer memory 5, and the next step S24 Then, the image compression / expansion circuit 6 starts the compression processing of the image data written and read into the buffer memory 5 immediately before the image freeze processing. Step S25
Then, it is determined whether or not the compression process has been completed. If it is determined that the compression process has not been completed, the determination in step S25 is repeated. If it is determined that the compression process has been completed, the process proceeds to step S26.

In step S 26, the compressed image data is recorded on the magneto-optical disk 14.

In the flowchart of FIG. 3, if there is an interrupt process from the voice recording switch 25 for performing voice recording between the processes from step S21 to step S25, for example, At the same time, the operation of the voice switch interruption process after step S30 in the flowchart of FIG. 4 is also performed.

In FIG. 4, in the audio switch interruption process in the still image mode in the audio recording switch 25 in step S30, it is determined in step S31 whether or not the audio recording switch 25 has been turned on. If it is determined that the voice switch has not been performed, the process proceeds to step S35, and returns to the time point of the voice switch interrupt processing in the flowchart of FIG. On the other hand, if it is determined in step S31 that the voice recording switch 25 has been turned on, the process proceeds to step S31.
At 32, the audio compression processing in the audio compression / expansion circuit 22 is started.

In the next step S33, it is determined whether or not the voice recording switch 25 has been turned off. If it is determined that the voice recording switch 25 has not been turned off, the determination in step S33 is repeated. , Step S34
Then, after ending the audio compression processing in step S34, the process returns to the audio switch interrupt processing point in the flowchart of FIG.

For this reason, in the flowchart of FIG. 3, step S2 following step S26 is performed.
In step 7, it is determined whether or not the audio compression processing has been completed.
The determination at step S27 is repeated, and if it is determined that the process has been completed, the process proceeds to step S28.

In step S28, the audio data on which the compression process has been completed is recorded on the magneto-optical disk 14, and then the process in the still image mode is terminated in step S29.

Next, in step S3 of FIG. 2,
In step S40 when the continuous shooting mode is selected, the processing of the flowcharts in FIGS. 5 and 6 is performed. That is, when the continuous shooting mode is selected, compression encoding is performed while the shutter button 16 is kept pressed,
The data is stored in the high-speed RAM 11, and when the remaining capacity of the RAM 11 becomes 0 or the shutter button 16 is released (turned off), recording is performed on the magneto-optical disk 14. In the continuous shooting mode, the image is recorded on the magneto-optical disk 14 with high image quality (at least 64 Kbytes or 128 Kbytes are used per image). Therefore, several images of image data are stored in the RAM 11 and then sequentially recorded on the magneto-optical disk 14. The sound recording in the continuous shooting mode is performed in the same manner as in the still image mode.

In the flowchart of FIG.
When the process proceeds from step S3 to step S40, the continuous shooting mode process is started in step S41. When the process in the continuous shooting mode is started, interruption of image freeze is permitted in step S42.

In the next step S43, it is determined whether or not the shutter button 16 has been turned on. If it is determined that the shutter button 16 has not been turned on, the determination in step S43 is repeated. S44
Proceed to. In step S44, the image freeze processing is performed in response to the shutter button 16 being turned on. In the next step S45, the image compression / expansion circuit 6 writes and reads out the buffer memory 5 immediately before the image freeze processing. The compression processing of the compressed image data is started.

In the next step S46, whether the remaining capacity of the buffer memory 5 is insufficient or the shutter button 1
It is determined whether or not No. 6 has been turned off.
If it is determined to be NO at step 46, the process returns to step S44 by freeze interrupt processing, and if it is determined that the remaining capacity of the buffer memory 5 is insufficient or the shutter button 16 is turned off, the process proceeds to step S47.

In step S47, the image freeze interrupt is prohibited, and in the next step S48, the compressed image data is recorded on the magneto-optical disk 14.

Also in the continuous shooting mode shown in the flowchart of FIG. 5, if there is an interruption process from the audio recording switch 25 for recording the audio, for example, during the processing from the step S41 to the step S48, At the same time as the processing for the image, the operation of the voice switch interrupt processing after step S60 in the flowchart of FIG. 6 is also performed.

In FIG. 6, in the voice switch interrupt processing in the continuous shooting mode in the voice recording switch 25 in step S60, it is determined in step S61 whether the voice recording switch 25 has been turned on, and the voice recording switch 25 is turned on. If it is determined that there is not, the process proceeds to step S65, and FIG.
Return to the time point of the voice switch interrupt processing in the flowchart of FIG. On the other hand, if it is determined in step S61 that the voice recording switch 25 has been turned on, the process proceeds to step S6.
In step 2, the audio compression processing in the audio compression / expansion circuit 22 is started.

In the next step S63, it is determined whether or not the voice recording switch 25 has been turned off. If it is determined that the voice recording switch 25 has not been turned off, the determination in step S63 is repeated. , Step S64
Then, after completing the audio compression processing in step S64, the flow returns to the audio switch interrupt processing point in the flowchart of FIG.

Therefore, in the flowchart of FIG. 6, step S4 following step S48 is performed.
In S9, it is determined whether or not the audio compression processing has been completed.
The determination at step 49 is repeated, and if it is determined that the processing has been completed, the process proceeds to step S50.

In step S50, the audio data on which the compression processing has been completed is recorded on the magneto-optical disk 14. Thereafter, in step S51, the continuous shooting mode processing is terminated.

Next, in step S4 of FIG.
In step S70 when the pseudo moving image mode is selected, the processing of the flowchart in FIG. 7 is performed. When the pseudo moving image mode is selected, when the shutter button 16 is pressed, a compression process is started, and the compression process is recorded on the magneto-optical disk 14. When the shutter button 16 is pressed again, the compression and recording are started. To end. That is, the pseudo moving image mode is a mode for recording a moving image in which the image quality is somewhat sacrificed as compared with the still image mode or the continuous shooting mode. For example, the image is compressed to 32 Kbytes per image, and 4 frames per second. This is a mode in which continuous shooting is performed continuously. In this case, since the average transfer speed from the compression unit of the image compression / expansion circuit 6 to the RAM 11 and the transfer speed from the RAM 11 to the magneto-optical disk 14 are substantially the same, unless the RAM 11 overflows or underflows, the optical transmission speed continues. A pseudo moving image can be recorded on the magnetic disk 14. In addition, by increasing the compression ratio,
Recording of about 0 frames is also possible. However, in this case, since the deterioration of the image becomes conspicuous, when displaying the image, the image is displayed by thinning out the image vertically and horizontally. Although continuous shooting in the continuous shooting mode can be performed at a high speed, continuous shooting is a mode in which a high-quality still image can be recorded for only a few seconds. This mode can record moving images even in the range. Furthermore, the sound in the pseudo video mode is
For example, as in a so-called camcorder, the sound being captured is recorded as it is.

In the flowchart of FIG.
When the process proceeds from step S4 to step S70, the pseudo moving image mode process is started in step S71. When the processing in the pseudo moving image mode is started, in step S72, interruption of image freeze is permitted.

In the next step S73, it is determined whether or not the shutter button 16 has been turned on. If it is determined that the shutter button 16 has not been turned on, the determination in step S73 is repeated. S74
Proceed to. In step S74, the audio compression / expansion circuit 22 starts audio compression processing. That is,
In this pseudo moving image mode, audio compression recording and end are performed in conjunction with the start and end of image compression recording.

In the next step S75, an image freeze process is performed. In the next step S76, the image compression / expansion circuit 6 compresses the image data written and read into the buffer memory 5 immediately before the image freeze process. Start processing.

In the next step S77, it is determined whether or not the shutter button 16 has been turned on again. If it is determined that the shutter button 16 has not been turned on, the process returns to step S75 and the same processing is repeated to determine that the shutter button 16 has been turned on. In this case, the process proceeds to step S78. Step S76 and step S76
77 and the magneto-optical disk 1 via the RAM 11
4 has begun recording. If it is determined in step S77 that the shutter button 16 has not been turned on and the process returns to step S75, the number of frames of the pseudo moving image is 1
In accordance with the number of frames per second, for example, a freeze pulse as shown in FIG. 8 (an example of a pulse in the case of 6 frames per second is shown in FIG. 8) is generated, thereby performing interrupt processing. To do.

In the step S78, the image freeze interrupt is prohibited, and in the next step S79, the audio compression processing ends.

In the next step S80, the compressed image data and compressed audio data are all
4 is determined. Step S80
If it is determined that no data is recorded in step S8,
The determination of 0 is repeated, and if it is determined that recording has been performed, the process proceeds to step S81.

In step S81, after the recording on the magneto-optical disk 14 is completed, in step S82, the processing in the pseudo moving image mode is completed.

The CPU 10 performs the judgments in the above-described flowcharts and controls the respective units.

As described above, the electronic still camera according to the embodiment of the present invention includes the image pickup device 1 for converting an image of a subject through an optical system into an electric signal, and the image pickup device 1
An image compression / expansion circuit 6 for compressing and encoding image information from the camera, a high-speed RAM 11 for temporarily storing high-quality continuous shot image compressed data, and a large-scale RAM for storing compression-encoded information. The optical disk includes a magneto-optical disk 14 having a capacity, a photographing mode switch 15 capable of switching a photographing mode such as a normal still image, a continuous photographing, and a pseudo moving image, and a CPU 10 capable of detecting the switching of the photographing mode. Since a large-capacity and inexpensive recording medium such as a so-called mini-disk is used as the magnetic disk 14, not only 1000 to 2000 still images but also tens of seconds or several minutes In addition, it is possible to record and reproduce high-quality continuous shot still images and audio of several seconds. Further, in the electronic still camera according to the present embodiment, a still image, a continuous photograph, a pseudo moving image, a sound, and the like can be mixedly recorded on one magneto-optical disk 14.

That is, in the electronic still camera according to the present embodiment, the user can freely and steadily record without worrying about the remaining number of recordable images and the cost per image. Not only pictures,
High-quality continuous shooting for several seconds, pseudo-moving images and sound for several minutes can be recorded on one recording medium.

[0077]

According to the electronic still camera of the present invention,
By compressing the image information from the imaging means by the image compression means and recording it on a large-capacity and inexpensive recording medium consisting of a magneto-optical disk, the number of images that can be recorded is increased, so that the user can It is possible to freely and steadily record without worrying about the remaining number of recordable images and the cost per image. In the electronic still camera of the present invention, the semiconductor memory means absorbs the difference between the transfer speed of the image information from the imaging means and the recording speed of the recording medium. This also enables recording of continuously shot images and pseudo moving images. Further, in the electronic still camera according to the present invention, the control means controls the compression by the image compression means, the writing / reading of the semiconductor memory means, and the recording on the recording medium in accordance with the operation of the operation means. By performing control to record a plurality of pieces of image information stored in the semiconductor memory means on the recording medium after the end of the compression, it becomes possible to take a picture without worrying about the recording state of the image. The control means starts the compression by the image compression means in response to the operation of the operation means, detects the remaining capacity of the semiconductor memory means, and terminates the compression by the image compression means when it detects that the remaining capacity has been exhausted. However, by controlling to record a plurality of pieces of image information stored in the semiconductor memory means on the recording medium, the semiconductor memory can be used effectively, and photographing can be performed without concern for remaining capacity.

In the electronic still camera of the present invention, since the audio information is also compressed, the recording medium can record the audio information compressed together with the image or separately from the image.

Further, in the electronic still camera of the present invention, since the image expanding means, the audio expanding means and the display means are provided, the compressed image information and audio information can be expanded. You can see the expanded image.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram illustrating a schematic configuration of an electronic still camera according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the electronic still camera according to the present embodiment in each shooting mode and after-recording mode.

FIG. 3 is a flowchart illustrating an operation in a still image mode.

FIG. 4 is a flowchart showing an audio switch interruption process in a still image mode.

FIG. 5 is a flowchart showing an operation in a continuous shooting mode.

FIG. 6 is a flowchart showing a voice switch interrupt process in a continuous shooting mode.

FIG. 7 is a flowchart showing an operation in a pseudo moving image mode.

FIG. 8 is a diagram illustrating an example of a freeze pulse.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Image sensor, 2 Driver of image sensor, 3, 21
A / D converter, 4,7 signal processing circuit, 5 buffer memory, 6 image compression / expansion circuit, 8,23 D /
A converter, 9 monitoring device, 10 CPU, 11
RAM, 13 disk driver, 14 magneto-optical disk, 15 shooting mode switch, 16 shutter button, 17 microphone, 18 audio line input terminal, 19 switch, 20, 24 amplifier, 22 audio compression / expansion circuit, 25 audio recording switch

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H04N 5/92 H04N 5/781 510E // H04N 101: 00 5/92 H

Claims (14)

[Claims] 1. An image pickup means for converting an image formed on an image pickup surface into an electric signal to obtain image information, an operation means, an image compression means for compressing the image information, and a plurality of compressed images Semiconductor memory means for temporarily storing information; a large-capacity recording medium for recording compressed image information; at least compression of the image compression means, writing / reading of the semiconductor memory means, and recording of the recording medium Control means for controlling the operation of the operation means, the control means starts the compression by the image compression means, and in response to the release of the operation of the operation means, the compression by the image compression means And controlling to record a plurality of pieces of image information stored in the semiconductor memory means on the recording medium after the end of the compression by the image compression means. Electronic still camera. 2. The electronic still camera according to claim 1, wherein the large-capacity recording medium is a predetermined disk. 3. The electronic still camera according to claim 1, further comprising image expansion means for expanding the compressed image information. 4. An audio information input means for inputting audio information, and audio compression means for compressing the audio information, wherein the semiconductor memory means also temporarily stores the compressed audio information, 4. The recording medium according to claim 1, wherein said compressed audio information is also recorded.
The electronic still camera according to any one of the above. 5. The electronic still camera according to claim 4, further comprising audio expansion means for expanding the compressed audio information. 6. The plurality of photographing modes include at least:
A still image mode for recording a still image on the recording medium, a continuous shooting mode for recording a continuous still image on the recording medium,
6. A pseudo-moving mode for recording a still image close to a moving image on the recording medium, and an audio recording mode for recording only audio on the recording medium. 2. The electronic still camera according to claim 1. 7. The electronic still camera according to claim 1, further comprising display means for displaying image information. 8. An image pickup means for converting an image formed on an image pickup surface into an electric signal to obtain image information, an operation means, an image compression means for compressing the image information, and a plurality of compressed images. Semiconductor memory means for temporarily storing information; a large-capacity recording medium for recording compressed image information; at least compression of the image compression means, writing / reading of the semiconductor memory means, and recording of the recording medium Control means for controlling the operation of the operation means, after starting the compression by the image compression means, detects the remaining capacity of the semiconductor memory means, the remaining capacity is lost Detecting that the image compression means terminates the compression by the image compression means, and controls to record a plurality of pieces of image information stored in the semiconductor memory means on the recording medium. Child still camera. 9. The electronic still camera according to claim 8, wherein the large-capacity recording medium is a predetermined disk. 10. An image decompressing means for decompressing the compressed image information is provided.
An electronic still camera as described. 11. An audio information input means for inputting audio information, and audio compression means for compressing audio information, wherein the semiconductor memory means also temporarily stores the compressed audio information, 9. The recording medium according to claim 8, wherein said compressed audio information is also recorded.
The electronic still camera according to any one of 0. 12. The electronic still camera according to claim 11, further comprising audio expansion means for expanding the compressed audio information. 13. The plurality of shooting modes include at least a still image mode for recording a still image on the recording medium, a continuous shooting mode for recording a continuous still image on the recording medium, and a continuous still mode close to a moving image. 13. The image processing apparatus according to claim 8, comprising a pseudo moving image mode for recording an image on the recording medium, and an audio recording mode for recording only audio on the recording medium. Electronic still camera. 14. The electronic still camera according to claim 8, further comprising display means for displaying image information.