JPH02203684A - Electronic camera - Google Patents

Abstract

PURPOSE:To improve the convenience of use as a system by providing a memory storing once a picture data compressed in the compression mode and storing the picture data into the memory till a recording means reaches the recordable state. CONSTITUTION:The camera is provided with a compression means 314 compressing a picture data to be recorded, means 241, 251 provided corresponding to the means 314 and selecting the compression mode, a memory 316 storing once a picture data compressed in the compression mode, and a discrimination means 317 discriminating whether or not the picture data stored in the memory 316 is able to be recorded in the recording means 15 and when it is discriminated not to be stored, the picture data stored in the memory 316 is stored in the memory 310 of the camera till the recording means 15 reaches the recordable state, e.g. till a new memory card 15 is loaded. That is, the picked-up picture data is warranted and the picture data is not transferred to the memory card 15 before the picture data is not recordable. Thus, the user selects the mode optionally without caring about the compression mode to attain the pickup.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an electronic camera that records still images using a memory card as a recording medium.

(Prior Art) In recent years, solid-state imaging devices such as CCDs (charge-coupled devices) and rotating magnets have been introduced as alternatives to conventional (still) cameras that use the exposure of photographic film to take and record still images. 2. Description of the Related Art Electronic cameras that take and record still images using recording media have been commercialized. However, since this type of electronic camera uses a rotating magnetic recording medium, it requires a drive device inside the camera to drive the rotating magnetic recording medium relative to the recording head. I don't think it's suitable for this. Therefore, the applicant has already proposed an all-solid-state electronic camera system that records image signals on a memory card using semiconductor memory as a system that does not require such a drive device and is advantageous for miniaturization ( For example, %Gan Sho 61-163711). An example of a typical configuration of such an electronic camera system is shown in FIG.

The image of the subject is formed on a CCD 126, which is an image sensor, via a lens 12), an aperture 122, and a color filter 120, and is photoelectrically converted by the CCD 126. ccnl
The output signal of 26 is subjected to predetermined processing in a preprocessing circuit 127, and then sent to an A/D (analog-digital) converter 12.
8, it is converted into a digital signal and recorded on the memory card 115.

The memory card 115 stores signals from each pixel of the image sensor.
It will be digitized and stored.

The signal of each pixel of the image sensor is processed by a preprocessing circuit 127.
Pre-processing includes, for example, amplification, white balance correction,
and predetermined processing such as r correction is performed. The preprocessed pixel data is recorded in the memory card 115 in the order according to the pixel arrangement. During playback, the data recorded on the memory card 115 is set in a playback device, subjected to necessary signal processing, and then D/A (digital-to-analog) converted and input to a TV (TV) monitor. and displayed as an image. In addition, FIG. 13 shows a Koos 110, a round release switch 111 that triggers the imaging operation, a battery 123 as a power source, an aperture 122 and a shutter control circuit 124 for controlling the electronic shutter operation, a CCD drive circuit 125, and A monitor section 130 is also shown. The CCD drive circuit 125 includes a shutter control circuit 124, a CCD 126, a preprocessing circuit 127, an A/D converter 128, and a memory card 115.
This is a circuit for controlling and driving.

The monitor section 130 displays a photographed image using a signal passed through the preprocessing circuit 127i during photographing, and is used as a finder.

In this way, the method of recording data corresponding to each pixel of a solid-state image sensor directly onto a memory card is simple, but the memory capacity required to record the image data for one screen of still images is limited. Depending on the conditions (modes), there may be times when you have taken a still image or one screen, but there is not enough space on the memory card to record it, or when new image data is added to the recording area where the image data of a certain screen was deleted. This creates an inconvenience in that even if an attempt is made to write, the capacity may be insufficient and recording may not be possible.

(Problem to be solved by the invention) As mentioned above, when the user changes the recording conditions (mode),
We thought of a method to record still images under arbitrary desired recording conditions, but there were problems in that the still images could not be recorded, or the erased image data could not be rewritten under different recording conditions. be.

Therefore, the present invention makes it possible to save captured still images even when the memory card does not have enough storage capacity, and furthermore, it is possible to erase any screen and create a new image. It is an object of the present invention to provide a new electronic camera that can flexibly deal with discrepancies in recording areas during recording.

[Structure of the invention]

(Rounding Means for Solving the Problem) The present invention provides a compression means for compressing image data to be recorded in an electronic camera equipped with a memory card for recording photographed image data, and a method corresponding to this means. means for selecting a compression mode, a memory for temporarily storing the image data compressed in the compression mode selected by the means, and nine stroke data stored in this memory, which can be recorded in the recording means. The image data stored in the memory when it is determined by this means to be rejected is stored in the memory until the recording means becomes ready for recording, for example, by a new memory card. This electronic camera is characterized in that the information is stored in the camera's memory until it is mounted.

(Function) The present inventors have previously proposed an electronic camera that has multiple compression modes and allows the user to select the mode as appropriate.
If memory cards with different compression ratios are selected, there will inevitably be excess memory capacity, or conversely, a capacity shortage in which one frame cannot be recorded. Therefore, the inventors of the present invention guaranteed the captured image data, and for example, when a new memory card is inserted, the image data can only be stored on the memory card when the image data can be recorded. Make a transfer. This allows users to select any compression mode and shoot without worrying about the compression mode.

(Example) Hereinafter, an example of an electronic camera according to the present invention will be described with reference to the drawings.

An electronic camera system consists of an electronic camera and a playback device. The former, an electronic camera, is a device that uses a semiconductor memory card as a recording medium to capture and record an image of a subject.The latter, an electronic camera, reads out image information recorded on a memory card from the memory card and displays it on a TV.
(Television) A device for displaying images on a receiver or the like.

FIG. 1 is a perspective view of the electronic camera as seen diagonally from the rear, and explanations of parts having the same functions as a normal camera will be omitted. The electronic camera 10 is provided with a release 11, an imaging mode changeover switch 12, an image capture number display section 13, and a reset button 9. Also, electronic camera 1
0 is provided with a ninth insertion slot 14 into which a semiconductor memory card 15 is inserted and removed from the right side. Further, the electronic camera 10 is provided with a shutter speed selection dial 18. Each of these parts will be explained in detail later.

FIG. 2 shows a schematic basic configuration of the electronic camera 10. When taking an image, similarly to a normal camera, focusing is performed by operating the lens system 2), and the shutter speed is selected and set by operating the shutter speed selection dial 18. Adjustment of the diaphragm is performed by the control circuit 24.
This is done by controlling the This electronic camera 1
0, shutter speed adjustment using a so-called electronic shutter is used. In the electronic shutter, the shutter speed is adjusted by controlling the charge accumulation time of the CCD array 26, which is an image sensor. An image of the subject is formed on the CCD array 26 via the lens system 2).

When the imaging operation is started and the series 11 is first pressed halfway (the release button is pressed halfway) by the operator, i.e., the user, the power supply voltage is applied to each electron from the power supply 23 using a battery. Supplied to the circuit section. The amount of incident light is measured by the exposure sensor 19, and the control circuit 24 controls the aperture 22 according to the amount of incident light.

The external color temperature is measured by the white balance sensor 17, and the control circuit 24 generates a white balance control signal in accordance with the measured color temperature.

When the release 11 is pushed further and the state changes from a half-pressed state to a fully-pressed state (a state in which the release button is fully pressed), the control circuit 24 generates a shutter pulse. The drive circuit 25 provides control signals to the CCD play 26, preprocessing circuit 27, A/D conversion circuit 28, and signal processing circuit 31 in response to the shutter pulse. In response to this control signal, the CCD array 26, preprocessing circuit 27, A/D conversion circuit 28, and signal processing circuit 31 operate.

An image information signal consisting of an analog signal outputted from the CCD array 26 is given to an A/D conversion circuit 28 via a preprocessing circuit 27, and is converted into a digital signal by the A/D conversion circuit 28. The digitized image information signal is further subjected to predetermined signal processing by a signal processing circuit 31. The digital image information signal output from the signal processing circuit 31 is supplied to the semiconductor memory card 15 together with a control signal including an address signal. In this way, the image information signal of the captured still image is stored in the semiconductor memory card 15 as a digital signal.

Prior to imaging, the user can selectively set the format of data to be stored in the semiconductor memory card 15 by operating the mode switch 12. The mode switch 12 is used to select and set a desired mode from a plurality of modes with different image quality.
The amount of digital data required to store one frame of image (therefore, one
number of image frames that can be stored on one memory card 15)
can be changed. For example, when set to mode 1, which is a high image quality mode, one frame of image is stored as high quality digital data of 640 bytes, and in mode 2, one frame of image is stored as 320 bytes of digital data, second only to mode 1. In mode 3, one frame image is stored in 160 bytes, which is the second highest image quality after mode 2, and in mode 4, which is the mode with the lowest image quality, one frame image is stored in 80 bytes. and is stored in the least amount of memory space per frame. For example, if the memory card 15 is equipped with 2.56 Mbytes of memory, one memory card 15 will receive 4 frames per memory card in mode 1, and 4 frames per memory card in mode 2, depending on the selected image quality.
8 frames can be stored in mode 3, 16 frames in mode 3, and 32 frames in mode 4.

Details of this method will be described later.

FIG. 3 shows the basic configuration of the memory card 15. The memory card 15 is composed of a printed circuit board on which a plurality of &W (random access memory) chips 36 are mounted. At one end of the memory card 15, an external terminal 32 including a data terminal, an address terminal, and a control terminal, and a power terminal 33 are provided. The memory card 15 is used by being loaded into the electronic camera 10 or the playback device. Power supply voltage is supplied to the memory card 15 via the power supply terminal 33, and signals are input and output to and from the memory card 15 via the external terminal 32. The memory card 15 has a built-in dedicated battery 34 to hold stored data. memory card 1
5 is provided with a power switching circuit 35, and when the memory card 15 is loaded into the electronic camera 10 or the playback device, the power source of the RAM chip 36 is switched from the built-in battery 34 to the power source 23 of the electronic camera 10. .

In FIG. 4, as a more specific example of the memory card 15, 20 1M bit AM chips 361 to 36□
. A memory card 15 using . At one end of the memory card 15, external terminals 32, -32. and a power supply terminal 33 are provided. External terminals 32) to 3
23 is an 8-bit data terminal 320, to address information. Address terminal 322 and control terminal 32 that receive
Consists of □.

The memory card 15 in FIG. 4 has 20M bits (2,
It has a capacity of 56 Mbytes). Control terminal 32° is R
It consists of a terminal C81 for selecting the AM chip 36, a terminal WP for write pulses, and a terminal CB for selecting a card when there are several playback cards.

Decoder 12), and 12 by input from terminal C8
) □ is selected. Decoder 12),
RAM chip 36. ~36□. corresponding to the decoder 12
)□ are RAM chips 36□1 to 36□. It corresponds to

For example, a CCD array 26, which is a solid-state image sensor, is used as an image sensor for capturing a frame image of a still image. The CCD array 26 used in the electronic camera of the present invention is, for example, a 7-frame interline transfer type CCD array.
OD play is suitable.

FIG. 5 shows a schematic configuration of an example of a frame interline transfer type CCD solid-state sensor.

In this CCD play, pixel light receiving sections 51 made of photoelectric conversion elements such as photodiodes are arranged two-dimensionally. The vertical transfer section 5 is adjacent to the pixel light receiving section 51 row of each column.
2 is provided. The charge in each pixel light receiving section 51 is transferred to the corresponding vertical transfer section 52 by field shift pulse φv1.
and is transferred via the transfer gate 53 to the charge storage section 54 which is a frame memory section. The signal charges in the charge storage section 54 are transferred to the output circuit 56 via the horizontal transfer section 55.
output as an electrical signal. A sweeping section 57 is provided at the other end of the vertical transfer section 52 .

In order to obtain a color image signal using only one CCD array, an optical system is installed on each pixel light receiving section 51 to separate R (red), G (green) and B (blue) light components. One color filter is placed. There are many known configurations of optical color filter types and arrangements.
The electronic camera of the present invention is not limited to any particular one.

The electronic camera 10 according to this embodiment will be described in detail with reference to FIG. 6, which shows a more specific configuration.

Before pressing the release 11, the user can select a desired mode by operating the mode switch 12, considering the image quality to be stored in the memory card and the number of frames to be stored in the memory card. The still image may be photographed by changing the mode one by one. The reason for this will be explained later. The selected mode signal is sent to the central processing unit (CP).
U) From 24□ to switch 31. is input. Note that when the memory card 15 is inserted into the camera body, the CPU 24,
reads the information of the memory card 15 (the number of file blocks used, etc. shown in the latter part), and is initialized in the case of a new card.

When the release 11 is pressed halfway, external color temperature information and exposure amount information are transmitted from the white balance sensor 17 and exposure sensor 19 to the I/F 24.
It is input to the CPU 24□ via. Based on the read exposure amount information, the CPU 241 controls the aperture p drive circuit 24. The diaphragm 22 is driven and controlled via the diaphragm 22. Also, C.P.
U24. Based on these white balance information and exposure amount information, the interface (I/F)
C via 243 and signal generator 251
This COD drive circuit 25 controls the CD drive circuit 252.
The drive of the CCD array 26 is controlled by □. moreover,
From CPU24□ to I/F24. The flash drive circuit 244 is controlled by a signal supplied through the flash drive circuit 244, and it is set whether or not the flash drive circuit 244 drives the flash 16, such as an electronic flash, during image capture. In addition, an amplifier circuit (amplifier) 271
and the color separation/r correction/white balance circuit 27□ are all connected from the CPU 241 to the I/F 24. It is controlled by signals given via the CPU 24, the I/F 24gP and the signal generator 25K.

Next, when the release 11 is pushed further and fully pressed, the signal generator 251), CCD array 26, amplifier 271, color separation/r correction/white balance circuit 271%, A/D conversion circuit 28, and signal processing circuit 313, filter 31! , sub-sample circuit 31s
1 data compression circuit 31 switch 31. Drive signals corresponding to each element are supplied to a memory interface (memory I/F) 31°.

In response to the operation of the release 11, image data is output from the CCD array 26. The image data is the amplifier 271
The G, G, and B signals are amplified to a predetermined level by the A/D converter 28 after passing through a color separation/white balance 11r correction circuit 27 consisting of a color separation circuit, a white balance circuit, and an r correction circuit. Ru. The R, G, and B digital signals output from the A/D converter 28 are converted into a luminance signal Y1 and color difference signals CRI and CBl by a signal processing circuit 311, and (the luminance signal Y1 remains unchanged) 2 The number of samples of the different types of color difference signals C1 and CBI is reduced to 1/2 and input to the low-pass filter 313. Luminance signal Y1, color difference signals CRI and CB 1
tf, the data is linearly quantized with one sample being 8 bits. What is the relationship between the sample points of the luminance signal Yl and the sample points of the color difference signals CR1 and CBI? It becomes as shown in Figure @7. Low pass filter 31! is the pre-lowpass filter for subsample rounding. The luminance signal Y1, color difference signals CR,1 and CB1 are passed through the low-pass filter 31! After passing through, it is applied to the sub-sampling circuit 31s. In the sub-sampling circuit 31m, the luminance signal is subjected to line offset subsampling to produce a luminance signal Y2 with 1/2 the number of samples.
In addition, the color difference signals C1 and CBI are sub-sampled every other line, resulting in color difference signals CR2 and CB2 having 1/2 the number of samples.

The relationship between each sample data point at this time is as shown in FIG. Luminance signal Y2, color difference signals C2 and CB2
is input to the data compression circuit 314. As already mentioned, the luminance signal Y2 and the color difference signals C2 and CB2 are
Each sample is linearly quantized with 8 bits per sample, but data compression circuit 31 reduces the number of data bits per sample.

In this embodiment, the data compression method is, for example, DPC.
Data compression is performed using M (differential pulse code modulation). Data compression using DPCM is a known technology,
Nonlinear compression and quantization of the difference between sample data and predicted values. For example, regarding the luminance signal Y22 in FIG. 8, the luminance signals Yll, Y12 . Y13. Y22 is predicted from already encoded data such as Y2), and the difference from the predicted value is nonlinearly quantized, and l samples are made up of 4 bits or 2 bits. Similarly, color difference signal CR2
and CB2 are also compressed, and one sample is made up of 4 bits or 2 bits. The brightness signal compressed in this manner is designated as Y3, and the color difference signals are designated as CR3 and CB3.

Switch 31. is provided to select the luminance signal and color difference signal according to the set mode. For example, when mode 1 is selected, the signal processing circuit 31m
The signals Yl, CRI and CBI outputted from the switch 31s are selected by the switch 31s and directly sent to the buffer memory 316
is stored in the memory card 15 via the . Similarly, in mode 2, the signals Y2 and C from the sample circuit 313
If R2 and CB2 are in mode 3, they are compressed by the data compression circuit 314 and the signal Y3. If CR3 and CB3 are in mode 4, the signals Y 3 , CR3 and CB3 compressed by the data compression circuit 314 and represented by 2 bits per sample are sent to the switches 31 . Selected accordingly. The signals selected by these switches 31g are stored in the memory card 15 via the buffer memory 316.

In addition to image data, 1 CPU indicates which mode is selected.
24. The information from is also stored in the memory card 15 at the same time as the image data. (For example, in mode 1, "001
", and in the case of mode 2, it is stored in a binary code indicating the mode number, such as roloJ. ) Further, the memory card 15 may also store imaging data such as whether or not to use a fludge gourd, white balance control data, exposure data (or aperture data), and shutter speed data in the same way as the mode in binary code. is also possible. This information is stored in the CPU24
．． The information is displayed on the display section 13, and the user, that is, the operator, can confirm this information on the display section 13.

The method of recording data to the memory card 15 is shown in FIG. 9(a).
This will be explained in detail with reference to (e). Here, as shown in FIG. 4, 1M bit RAM, for example SRAM
An example will be described in which a 20 Mbit, ie, 2.56 Mbyte memory card in which 20 (static RAM) are mounted is used.

As shown in FIG. 9(a), the entire memory space is divided into a directory area and a FAT (file allocation
table) area and data area. As shown in FIG. 9(b), the directory area contains the file number, that is, the image (if the file is image data).
frame) number, information indicating information classification, i.e., image data, audio data, or other data;
In case of image method, that is, image52. /60 series or 6251
50 series, image mode, that is, information that shows the image compression method (including a mode without compression), audio mode, that is, information that shows the compression method in the case of audio data, information that shows the year of recording (imaging), Information indicating the month of recording,
Information indicating the date of recording, information indicating the time of recording, and information indicating the number of minutes recorded are each written in 1 byte, and the number (entry block number) of the data block into which the file (image data file) is extracted and this number are also written. Writes the number of data blocks used to store the file. This directory area has 16 bytes per file and 256 bytes.
Allocate the file (256 frames for images).

Therefore, the directory area is 4 KB. FIG. 9(C) shows the structure of the FAT area, and FIG. 9(d) shows the structure of the data area. 256 bytes are prepared in the FAT area, and addresses are assigned from address OOH to address FFH. The data area is divided into 10 byte blocks, and block numbers QQH and FEB are assigned to each block.

To simplify the explanation, assume that approximately 40 bytes are required to record one frame of data, for example. In this case, the IJ block number is written as 11H1 and the number of used blocks as 04H, for example, in the directory area. F.A.
12H at address 11H in T area, 13H at address 12H
, 2AH at address 13H, and FFH at address 2AH.
Write.

This one frame of image data is 4 which links block numbers 11H, 12H, 13H and 2AH in the data area.
0 is written to the byte area.

FFH written to address 2AH in the FAT area indicates that it is the last block. FIG. 9(e) shows a 40 byte memory area with linked blocks. The first block, 256 bytes of block number 11H, indicates whether or not flash is used, white balance data,
Data on imaging conditions including exposure value (or aperture value) and shutter speed value are recorded, and the remaining 252 bytes are reserved as a user area for recording, for example, a title. Image data is continuously recorded from the 257th byte to block number 2AH. Mode 1 mentioned above
In this case, 64 blocks are used, in mode 2 32 blocks, in mode 3 16 blocks, and in mode 4 8 blocks.

With this method, even when variable length encoding is used in which the required memory capacity after encoding differs for each frame, recording on a memory card can be performed without any problem. That is, after encoding, the data is stored in the backup memory 316. The capacity of the buffer memory 316 is set to the capacity required to store at least one frame. ,1
The memory capacity required to record frame data is
Since it is known from the usage status of the rough memory 316, it is possible to calculate how many data blocks are to be used based on this information. Further, if the number of unused blocks in the memory card is insufficient, the image data is stored in the buffer memory 31a, and the next imaging cannot be continued unless a new memory card is inserted. or,
When the nine-stroke data stored in the buffer memory 316 is no longer needed, the buffer memory 31 is refreshed by pressing the reset button 9 in FIG.

The processing procedure (operation of the CPU) for performing such recording will be explained in detail with reference to the flowchart shown in FIG.

First, when the memory card 15 is inserted into the camera body, the memory I/F 31. Through the CPU 24. detects insertion of the memory card (step 8T1), and at the same time reads directory information (already used file types, number of used blocks, etc.) of the memory card 15 (step ST2). On the other hand, when the buffer memory is cleared, it is determined whether new data can be written (step 8T3). If possible, the set mode information (modes 1 to 4) is read (step 5T4),
Accordingly, the selection of the switch SW 31a changes every time the mode information is changed by the mode switch.

Then, when an operation input for the release 11 that determines the imaging timing is given (step 5T6), imaging information to be written to the directory area of the memory card 15, such as information on whether or not to use a flash, white balance information, exposure value ( (or aperture value) information, shutter speed information, year information, month information, day information, and time information (step ST7). Note that the mode information and memory card directory information have already been imported. Based on this information, the entry block number of the memory card 15 is set (step 5T8). Further, based on the mode information, the number of data blocks used to store the captured image is determined (step 5T9).
). The storage capacity of the installed memory card 15 is checked, and if the necessary number of data blocks for storing images cannot be secured in the memory card 15 (step 8T10), (display on the display unit 13 or as appropriate) If a new memory card 15 is inserted (step 8T14), the process returns to step 8T1. If the number of data blocks required to store images can be secured in the installed memory card 15 (step 1sTIQ), the FAT address of the memory card 15 is assigned (step STI1). , the image data and the above-mentioned imaging information are stored in the memory card 15 (step 8T12).

After transferring all data to the memory card, clear the buffer memory and record it in the buffer memory (Step 8T13)
.

Meanwhile, a new memory card is inserted, and step S
When returning to the TI, the directory information of the new memory card is read again (step 5T2).

If the number of blocks to be written to the memory card is less than 9 and a new memory card is inserted, the buffer memory has not been cleared (step 5T3), so the process of step ST8 for setting the entry block group of the memory card is performed and step ST9. 5T10.5TII, 5T12,5
Ends after T13t.

On the other hand, if a new memory card is not installed, the image data stored in the buffer memory 316 is discarded by a reset signal from the reset button 9 (step 5T15).

The method explained in FIG. 10 temporarily stores image data in a buffer memory according to the mode set for still image shooting, and then determines whether this data can be input to the memory card. However, a method may also be used in which the user is informed whether or not input is possible in a set mode prior to photographing. In this case, memory card 1
Since the directory information No. 5 is managed by the CPU 241, when the CPU 241 determines that photographing is not possible in the set mode, a display is displayed on the display unit 13 or an alarm (buzzer) is issued.

In FIG. 10, step 5T10, step 14
is provided before step ST6. Naturally, the reset button 9 becomes unnecessary.

Furthermore, the display unit 13 may display whether or not it is possible to take the first picture in the set mode.

Moreover, even though the camera's mode setting was set to mode 1 (640K) when the capacity of the memory card 15 was 80 in mode 4 and only the number of byte blocks remained, the warning was issued. When is pressed, the camera may be forcibly set to mode 4 and input to the memory card 15. Next, a playback device that reads image data from the memory card 15 and displays the video on a TV monitor or the like will be described with reference to FIG.

When the memory card 15 is inserted into the playback device 90 and a file number (image number) is specified by operating the keyboard 104, the CPU (central processing unit) 1o2 reads the memory card via the card interface (card I/F) 91. Reads the information of the directory area. The CPU 102 checks whether the information classification of the specified file number is image data, what the image format is, and what the compression mode is, and also recognizes the entry block number. Next, C.P.
UI O2 reads information on all block numbers from the FAT area. CPU 102), the block number is given to the card I/F 91, and the card I/F 91 generates an address according to the block number and transfers the image data to one
Read byte by byte.

Further, the CPU 102 controls the signal processing path according to the image format and mode information read out previously. For example, when the mode is mode 3, the data compressed to 4 bits is returned to 8-bit linear quantized data by the data restoration circuit 92, and when the mode is mode 4, the data is returned from 2 bits to 8 bits. In modes 1 and 2, the read image data is input to the interpolation circuit 94 without passing through the data restoration circuit 92. The interpolation circuit 94 outputs the luminance signal Y and two color difference signals CR and CB, and writes one frame of data into the frame memory 95. In addition, in modes 3 and 4, the image data is transferred to the data restoration circuit 9.
2 and the interpolation circuit 94 to be written into the frame memory 95.

Note that route control according to the above-mentioned modes is performed as follows.

The mode signal output from card I/F91 is
The signal is input to the determination circuit 100 via 102, and the mode is determined by the determination circuit 100. Depending on the determination result in the determination circuit 100, the state of the switch 106 is switched, and the data restoration circuit 92 and the interpolation circuit 9
The operation of No. 4 is also controlled by switching.

Further, data other than the image data output from the card I/F 91 is sent to the frame memory 9 via the data circuit 93.
5, it is stored in the same way as the image data. After one frame of data is written in the frame memory 95, a read clock is supplied from the signal generator 103 to this memory 95, and the luminance signal Y1 color difference signal CR and C
B is read out. Luminance signal Y and color difference signals CR and C
B is converted back to an analog signal by a D/A (digital-to-analog) converter 96 and sent to the TV monitor 107.
The input method is R (red), G (green) and B.
(Blue) input method, analog R, G and B signals are generated by the matrix circuit 97 and output to the TV monitor 10.
7 is input.

If the input method of the TV monitor 107 is an NTSC composite input method, the analogized luminance signal Y1 color difference signal CR and CB are converted into a composite signal by the first encoder 98 and the second encoder 99 and then output to the TV.
It is input to the monitor 107. If the input method of the TV monitor 107 is the Y-〇 separate input method, the analogized luminance signal Y1 color difference signals CR and CB are converted into a luminance signal Y and a color signal C by the first encoder 98. It is input to the TV monitor 107.

In the manner described above, images captured and stored in the memory card 15 can be displayed. Of course, it is also possible to make note copies by connecting output terminals such as the R, G and B output terminals to a video printer, for example.

Next, in the system of the present invention, it is also possible to erase every recorded image t-1 frame. This image erasure for each frame is performed as follows.

When you operate the keyboard 104 of the player to specify the image number and issue an erase command, the CPU 102
The directory area of the memory card 15 is searched via F91 to find an image number (file number) that matches the designated image number. When the designated image number is found, FFH is written in the area of the image number, entry block number, and number of blocks used in the corresponding directory. Furthermore, the storage contents of the addresses that were used in the FAT area are erased (OOH is written to all applicable addresses).

In addition, in the case of an electronic camera, when adding and recording the entire image of one frame, (under the control of the CPU 241)
The T area is searched for the address where OOH is written. The smallest address in which OOH is written is set as the entry block number, the required number of blocks is calculated from the memory capacity required to store one frame, and the address for linking the blocks to the FAT area is written. Next, data such as a file number and information classification are written into one of the empty directories (the file number is FFHO), and the entry block number and the number of used blocks are written into the last two words. Thereafter, imaging condition data such as whether or not a flash is used and image data are sequentially written into the linked blocks. As a result of searching the FAT area, if the number of blocks is insufficient for image storage, a signal indicating that writing is not possible is generated, and in response to this signal, for example, a warning indicating that writing is not possible is displayed on the display unit 13. is displayed. This warning may be displayed, for example, by lighting an LED (light emitting diode).

In the above, the case where one block is IOK bytes was explained as an example, but if the memory capacity required to record one frame of image data varies minutely, the size of one block may be made smaller. Alternatively, the minimum memory capacity required to record one frame may be one block.

Moreover, although the case where the luminance signal Y and the two color difference signals CR and CB are used has been described above, the 几-Y and BY signals may be used as the color difference signals. These signals Y, R-Y and B-Y are obtained from the R, G and B signals as follows: Y=0.3OR+0.59G+0.11BR-Y=
0.7OR-0,59G-0,11BB-Y=-0
, 30 - 0,59G + 0.89B. Similarly, it is also possible to use the optical and Q signals as the two color difference signals.

Furthermore, in the above, we have explained the case where data is compressed using DPCM in order to reduce the bit capacity of one sample, but such data compression may involve differences in the method of creating prediction signals or quantization for nonlinear quantization. There are various methods depending on the selection of the encoder, or transform encoding (transform coding).
There are many methods, such as using m coding. No matter what method is used, it is possible to cope with the problem by storing information indicating which method has been adopted as mode information in a memory card as binary data.

Furthermore, FIG. 12 shows a configuration according to another embodiment of the present invention, and in this embodiment, A/
D conversion circuit 28, signal processing circuit 311, filter 312
, sub-sample circuit 31ss, the part consisting of theta compression circuit 314 and switch 316 is connected to mixer circuit 41, A/
It is replaced with a D conversion circuit 281, a YC processing circuit 42, a filter 31', a data compression circuit 314', and a switch 3111. In this embodiment, the R, G, and B signals output from the color separation/γ correction/white balance circuit 272 are combined in a mixer circuit 41, and then the A/D conversion circuit 28'
The luminance signal and color difference signal outputted from the YC processing circuit 42 are supplied to the data compression circuit 3141 via the filter 31s1. The input and output of data compression circuit 314' are selected by switch 31a'.

〔Effect of the invention〕

According to the present invention, it is possible to provide an electronic camera and an image recording method thereof that are easy to use as a system including a memory card as a recording medium.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the external appearance of an electronic camera according to an embodiment of the present invention, FIG. 2 is a diagram showing a schematic configuration of an electronic camera according to the embodiment, and FIG. 3 is a diagram showing the structure used in the camera according to the embodiment. A perspective view for explaining the basic configuration of a semiconductor memory card,
Fig. 4 is a block diagram for explaining the detailed structure of the memory card, Fig. 5 is a diagram showing a schematic structure of the CCD array used in the same embodiment, and Fig. 6 is an electronic diagram of the same embodiment. A configuration diagram showing the configuration of the camera shown in FIG. 2 in more detail;
Figures 7 and 8 are diagrams for schematically explaining sample points of image data in the same embodiment as positions on a two-dimensional plane, and Figure gg9 explains the recording format in the memory card in the same embodiment. Fig. 10 is a flowchart showing the detailed procedure of processing during image capture in the same embodiment, and Fig. 11 is a schematic configuration of a reproducing machine for reproducing images captured by the camera of the present invention from a memory card. 12 is a block diagram showing the detailed structure of another embodiment of the present invention, and 131i0 is a diagram for explaining a conventional electronic camera. 11... Release, 12... Mode switch, 15
...Memory card, 16...Flash, 17...
・White balance sensor, 19...Exposure sensor, 2
)...Lens, 22...Aperture, 24...Control circuit, 25...Drive circuit, 26...CCD array, 27
...Preprocessing circuit, 28...A/D converter, 29...
- Data recording circuit, 31... signal processing circuit. Agent Patent Attorney Nori Ken Yudo Matsuyama Hikaru Diagram CR4 R2 Directory Diagram CB Beak B2 Memory Cart Contribution Seibo (0・N (C) Diagram Diagram Diagram Diagram

Claims (2)

[Claims] (1) In an electronic camera equipped with a recording means for recording photographed image data, a means for compressing the image data to be recorded and a means for selecting a compression mode provided corresponding to this means are provided. means, a memory for temporarily storing the image data compressed in the compression mode selected by the means, and a determining means for determining whether the image data stored in the memory can be recorded in the recording means. The electronic camera is characterized in that, when it is judged as negative by this means, the image data stored in the memory is stored in the memory until the recording means becomes in a recordable state. (2) The image data stored in the memory when the determination means according to claim 1 makes a negative determination continues to be stored in the memory until a new recording means is attached and becomes ready for recording. electronic camera.