JPH06237431A - Electronic still camera - Google Patents

Abstract

PURPOSE:To obtain the electronic still camera using a mini-disk(MD) inexpensive and having a large storage capacity as a recording medium. CONSTITUTION:The electronic still camera is made up of an image pickup section 11, an MD camera main body 10 and a mini-disk 30 loaded freely removably. A picture picked up by the image pickup section 11 is outputted as a picture signal of raster scanning form as an output signal 120, and given to an input of an amplifier 16 in the inside of the MD camera main body 10. A picture signal amplified by the amplifier 16 is converted into a digital signal 124 by an A/D converter 18 and subject to prescribed correction processing by a signal processing section 20. Digital picture element data 126 are recorded to a rewritable area 31 of the mini-disk 30 in the order of addresses by an MD controller 26. Programs (firmware) and data controlling the operation of the electronic still camera are read from a ROM area of the mini-disk 30 and stored in an internal storage section of a system controller 28 and they are used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic still camera, and more particularly to an electronic still camera using a mini disk as a recording medium.

[0002]

2. Description of the Related Art Conventionally, in electronic still cameras, as is well known, image signals picked up by a solid-state image pickup device are transferred to a floppy disk or a memory card (SRAM, FLUSH CARR).
D) is recorded as a recording medium. At the time of recording, the electronic still camera converts an image signal into a digital signal, compresses the data amount to a desired data amount or less by a conversion method such as two-dimensional orthogonal transformation, and stores the data amount in a recording medium.
For example, in the two-dimensional orthogonal transform method, one screen of image data is divided into blocks of a predetermined number and size, and the image data of each block is transformed into spatial frequency domain data, that is, transform coefficients by two-dimensional orthogonal transform. . This conversion coefficient is truncated at a portion equal to or less than a predetermined threshold value, and the rest is divided by a quantization step based on the normalization coefficient,
By this, normalization is performed. The normalized transform coefficient is then compressed by being run-length and Huffman encoded and stored in the image data recording medium. As a result, the storage capacity of the recording medium is used efficiently.

[0003]

However, in the prior art, both the floppy disk and the memory card have a small storage capacity as the recording medium for the image data of the electronic still camera, so that the recording of the image on the recording medium is performed. In order to increase the number of sheets, the compression coding of the above image data was indispensable. Further, it takes a considerable time to compress and encode each image and record it on a recording medium.
Further, there is an unsolved problem that the price of the memory card becomes expensive when the storage capacity of the memory card is increased.

An object of the present invention is to solve the above drawbacks of the prior art and to provide an electronic still camera using a mini disk which is inexpensive and has a large storage capacity as a recording medium.

[0005]

In order to solve the above-mentioned problems, the present invention captures an object scene image, converts an image signal representing the imaged object scene image into digital image data,
In an electronic still camera that records this image data on a recording medium, the recording medium is a mini disk having a read-only area and a rewritable area, and the camera includes an image pickup means for taking a scene image and Signal processing means for performing signal processing of image data sent from the imaging means, image recording means for recording the image data processed by the signal processing means in the rewritable area of the mini disk, imaging means, signal processing means, and The control means controls the image recording means, and controls a series of timings from the photographing of the object scene image by the imaging means to the writing of the image data in the rewritable area of the recording medium.

The control program and data are stored in the read-only area of the recording medium, and the control means may read and use the control program and data from the read-only area during operation.

Further, compression processing means for compressing and coding the image data processed by the signal processing means may be provided.

Furthermore, the compression processing means may be configured so that the compression encoding of the image signal can be released by selection.

[0009]

According to the present invention, the image pickup means photographs the object scene image, and the signal processing means performs signal processing of the image data sent from the image pickup means. The image recording means uses a mini disk having a read-only area and a rewritable area as a recording medium, and records the image data processed by the signal processing means in the rewritable area. The control means controls a series of timings from the photographing of the object scene image by the imaging means to the writing of the image data in the rewritable area of the recording medium.
A control program and data are stored in the read-only area of the recording medium, which is read out and used at the time of operation. Further, the compression processing means can compression-encode the image data processed by the signal processing means, and can release the compression-encoding of the image signal by selection.

[0010]

Embodiments of the electronic still camera according to the present invention will now be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals represent the same or corresponding parts. FIG. 1 is a schematic block diagram showing an embodiment of an electronic still camera (hereinafter referred to as an MD camera) using a Mini Disk (for example, a recording capacity of about 130 MB) of the present invention. 4 and 5 are schematic block diagrams showing modified examples of the embodiment shown in FIG.

Referring to FIG. 1, the MD camera includes an image pickup unit 11
And MD camera body 10. The image pickup unit 11 is an optical image pickup system including a taking lens 12, a diaphragm 13, and a solid-state image pickup device 14, and takes an image of the object scene based on an instruction from the MD camera body 10. The solid-state imaging device 14 is composed of, for example, a CCD (charge coupled device). This CCD captures an image of one frame by a series of operations of accumulating, transferring, and discharging charges on the image plane. In the case of continuous shooting, it is possible to capture an image of several frames per second by repeating the above series of operations. The image signal is output in the form of, for example, R, G, B color component signals. This color component signal is output (120) in the same raster scanning format as the TV signal, and the MD camera body 10
Connected to the input of the internal amplifier 16.

The MD camera body 10 is a system controller
Under the control of 28, the image signal for each one-shot image pickup in the image pickup section 11 is sent to the A / D converter 18 via the amplifier 16 and converted into a digital image signal 124. The digital image signal 124, which is the output of the A / D converter 18, is connected to the input of the signal processing unit 20, is subjected to predetermined correction processing, and is connected to the input of the compression processing unit 22. Input digital image data 12
6 is compression-coded in the compression processing unit 22 by, for example, an orthogonal transform coding method. The compression-encoded digital data 128 is temporarily stored in the data buffer unit 24 for one frame and then read by the MD controller 26 in the address order in synchronization with the writing speed to the mini disk 30 (130). Rewritable area of Mini Disc 30
Written to 31 (140).

The amplifier 16 is a circuit for amplifying the minute image signal 120 sent from the CCD 14 to an appropriate level. A
The / D converter 18 is a circuit that converts the image signal 122 amplified by the amplifier 16 into a digital image signal 124. This A / D
Digital image signal 124 converted in converter 18
Are quantized to 8 bits for each of the color component signals R, G and B.

The signal processing unit 20 includes a digital image signal 124
It is a circuit that performs signal processing such as white balance adjustment, gamma correction, and color difference signal processing on the image data converted into. Digital image data 12 processed by the signal processing unit 20
6 is sent to the compression processing unit 22.

The compression processing section 22 uses the digital image data 12
This is a circuit for compression encoding 6. More specifically, the image data for one frame is subjected to orthogonal transform coding in block units of a plurality of pixels. As the orthogonal transform, for example, a two-dimensional discrete cosine transform (DCT) is applied. As a result, each block is converted into spatial frequency domain data, and the data is sequentially arranged in the horizontal and vertical directions of the screen from a low frequency. In encoding, the image data that has been two-dimensionally orthogonally transformed is subjected to coefficient truncation for transform coefficients, and then normalized. Coefficient truncation is to compare the orthogonally transformed transform coefficient with a predetermined threshold value and discard the part below the threshold value. The normalization is to perform quantization (compression) with the normalized coefficient by dividing the transform coefficient, which has been truncated, by a predetermined quantization step value. Therefore, a non-negligible processing time is required to perform the compression processing. The compression processing unit 22 is configured to be able to bypass the compression processing function by selecting a selection switch (not shown). That is, since the recording capacity of the mini disk 30 as a recording medium is large and a sufficient image can be recorded, the provision of the compression processing unit 22 is not a necessary condition.

The data buffer section 24 is the signal processing section described above.
20 and image data 12 processed by the compression processing unit 22
8 is temporarily stored in the buffer memory for one frame.
The image data temporarily stored in the buffer memory is read by the MD controller 26 in the order of addresses (130).
The MD controller 26 converts the read image data into a predetermined format and writes the rewritable area 31 of the mini disk 30.
Write to (140).

The mini disk 30 is a hybrid flexible magnetic disk having a read-only area 32 for reproduction and a rewritable area 31 for recording and reproduction.
The read-only area 32 is an electronic still camera (image pickup unit 11 and
A ROM area in which firmware of the MD camera body 10) and control parameters (aperture, focus, zoom value, camera gamma correction value, matrix coefficient, etc.) of the camera are recorded in advance. The rewritable area 31 is
This is an area in which the data 140 sent from the MD controller 26 can be written. The mini disk 30 is a recording medium that can be easily attached to and detached from the MD camera body 10.

The system controller 28 is the MD camera body.
After the power of 10 is turned on, the firmware and control parameters of the electronic still camera are read from the read-only area 32 of the mini disk 30 and stored in a storage unit (not shown) inside thereof. The system controller 28 is a control unit that controls timing, data processing, and the like for each component of the electronic still camera based on this information. In addition,
The exchange of control information and timing information (102 to 114) between the system controller 28 and each component is performed via the system bus 100 of the system controller 28.

Next, the operation in the case of taking a picture with the electronic still camera of the present embodiment having the above-mentioned structure will be described.
First, when the operator turns on the power of the electronic still camera and mounts the mini disk 30, the camera firmware is loaded from the mini disk 30 and stored in the internal storage section of the system controller 28 under the control of the system controller 28. The camera is ready for operation. Then, when a shutter switch (not shown) is pressed, the CCD 14 sequentially photoelectrically converts and outputs the image of the field formed on the image forming surface via the lens 12. This image signal is amplified by the amplifier 16 and digitally converted by the A / D converter 18. The digital image signal 124 is subjected to gamma correction processing and color difference signal processing in the signal processing section 20, and is sent to the compression processing section 22. Here, the look-up table (LUT) for gamma correction and the matrix coefficient for color difference signal processing in the signal processing unit are determined by the control parameters read from the mini disk 30. As for the control parameters, some selection items can be selected by a selection switch (not shown), and if different ones from the current settings are selected, the corresponding control parameters are loaded from the mini disk 30 to the system controller 28. It has become. Therefore, the operator can select the control parameter according to the shooting conditions of the scene and can press the shutter switch of the camera.

The digital image data 126 output from the signal processing unit is subjected to the above-mentioned compression processing in the compression processing unit 22. At this time, the compression processing function can be bypassed by selecting the selection switch. This is because by using the mini disk 30 as a recording medium, it is possible to store a sufficient number of frames of image data without performing compression processing. The image data 128 output from the compression processing unit 22 is temporarily stored in the data buffer unit 24, then read by the MD controller 26 and recorded in the rewritable area 31 of the mini disk 30 in a predetermined format.

Next, it is assumed that the ROM area 32 of the mini disk 30 stores a plurality of types of picture patterns as illustrated in FIG. 2, for example. When the operator selects and sets the pattern of FIG. 2 in advance, the pattern data is read from the ROM area 32 by the MD controller 26.
The read pattern data is stored in the data buffer unit 24. In this state, when the operator presses the shutter switch of the camera, the captured image data is combined with the pattern data (for example, the image data is masked with the pattern data) to form the combined image shown in FIG. Become. This composite image is read by the MD controller 26 from the data buffer section and recorded in the rewritable area 31 of the mini disk 30 in a predetermined format.

In this case, as shown in the configuration example of FIG.
ROM part provided in the body of MD camera 10 instead of M area 32
It may be stored in 40. By doing so, it is not necessary to write the pattern data in the ROM area 32 of the mini disk 30, and the mini disk 30 can be easily manufactured. If the ROM section 40 is replaced, the operator
You can enjoy synthesizing more varied pattern data and images. Alternatively, the ROM of the mini disk 30
Area 32 stores standard pattern data and ROM
The special pattern data according to the operator's preference may be stored in the section 40. In this case, the system controller 28 determines the operator's selection settings, reads the selection pattern data stored in the ROM area 32 or the ROM section 40 of the mini disk 30, and then the data buffer section 24
To store.

Next, FIG. 5 shows a modification of the above embodiment. Referring to FIG. 5, the data buffer section 24 in the main body of the MD camera 10 has an external output function and can be connected to the external monitor 200. Further, the system controller 28 has a standard interface connection function (for example, SCSI, GPIB, RS232C, etc.), and is configured to be capable of transmitting data with an external device. In addition, in the ROM area 32 of the mini disk 30, the external monitor 20
Firmware for 0, firmware for data transmission, and firmware for camera photography are recorded.

The operator can select the MD camera body 10 by using a selection switch (not shown) provided on the MD camera body 10.
10 functions are used as (1) electronic still camera,
(2) Rewritable area 31 of the mini disk 30 on the external monitor 200
Is used as a controller for displaying the image recorded in, or (3) is used as a controller for transmitting the image recorded in the rewritable area 31 of the mini disk 30 to an external device by data transmission. ,
Can make a decision. When the operator selects one of the above functions, the firmware suitable for that function is transferred from the ROM area 32 of the mini disk 30 to the system controller 2
Loaded to 8. By configuring the MD camera body 10 as described above, the ROM, RA
M can be minimized and have many functions.

As in the above embodiment, the firmware of the electronic still camera is stored in the ROM area 32 of the mini disk 30.
This means that the firmware can be upgraded by supplying the media as a mini disk without replacing the ROM element in the camera.

[0026]

As described above, according to the present invention, since the mini disk is used as the recording medium of the electronic still camera,
The cost of the recording medium can be reduced, and the recording capacity can be significantly increased.

Further, since the recording capacity of the recording medium is significantly increased, the compression processing means can be removed from the electronic still camera, and the cost of the electronic still camera body can be reduced and the image quality can be improved. .

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of an electronic still camera using a mini disk of the present invention as a recording medium.

FIG. 2 is a diagram showing an example of pattern data stored in a ROM area in the embodiment shown in FIG.

FIG. 3 is a composite image diagram in which captured image data and selected pattern data are composited and recorded in the embodiment shown in FIG.

FIG. 4 is a block diagram showing a schematic configuration of a modified example in which a ROM section for storing special pattern data is added in the embodiment shown in FIG.

5 is a block diagram showing a schematic configuration of a modified example in which the camera main body is made multifunctional by adding an image sending function and a data transmitting function in the embodiment shown in FIG.

[Explanation of symbols]

 10 MD camera body 11 Imaging unit 12 Shooting lens 13 Aperture 14 Solid-state imaging device (CCD) 16 Amplifier 18 A / D converter 20 Signal processing unit 22 Compression processing unit 24 Data buffer unit 26 MD controller 30 Mini disc 31 Mini disc rewriting Possible area 32 Read-only area (ROM area) of mini disk 40 ROM section 200 External monitor 300 Standard interface

Claims (4)

[Claims] 1. An electronic still camera for photographing an object scene image, converting an image signal representing the imaged object scene image into digital image data, and recording the image data on a recording medium. The medium is a mini disk having a read-only area and a rewritable area, and the camera is an image pickup means for picking up a scene image, and signal processing for performing signal processing on image data sent from the image pickup means. Means, an image recording means for recording the image data processed by the signal processing means in a rewritable area of the mini-disc, and controlling the image pickup means, the signal processing means and the image recording means, and controlling the image pickup means in the image pickup means. An electronic still camera, comprising: a control unit that controls a series of timings from photographing a scene image to writing image data in a rewritable area of the recording medium. . 2. The electronic still camera according to claim 1, wherein a control program and data are stored in a read-only area of the recording medium, and the control means operates from the read-only area during operation. An electronic still camera characterized by reading and using data. 3. The electronic still camera according to claim 1, wherein the camera includes compression processing means for compression-encoding the image data processed by the signal processing means. . 4. The electronic still camera according to claim 3, wherein the compression processing means can cancel the compression coding of the image signal by selection.