JPH10108133A - Image pickup device and its control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow even an information processing unit having a different kind of environment to simply read and reproduce video data to be picked up. SOLUTION: When an image pickup instruction (depression of a shutter) is received from an operation section 114, luminance and color difference data from a signal conversion section 104 are stored once in a video memory 116, the data are coded into data of the JPEG system by a coding section 108 and stored in a memory 111. Then the same video data stored in the video memory 116 are thinned this time, an RGB conversion section 107 converts the data form into the RGB form and the resulting data are stored in the memory 111. Then link information denoting the relation of the two coded data stored in the memory 111 is generated, and the link information and the coded data are unified and stored in a recording medium in a recording section 113.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an imaging device and a control method thereof.

2. Description of the Related Art In the shooting and recording of digital video,
Because it is necessary to transmit and record large-capacity video signals at high speed,
A technique has been used in which the amount of information is efficiently reduced by an encoding compression technique such as PEG, and the image quality is hardly degraded.

It is assumed that, for example, a configuration shown in FIG. 2 is employed as a photographing apparatus (digital camera) that performs such encoding and compression processing. Hereinafter, description will be given with reference to FIG.

[0003] A captured image is formed on an image sensor 102, which is a CCD here, through a lens 101, converted into an electric signal by photoelectric conversion, and further converted into an A / D signal.
The signal is converted into a digital signal by the converter 103. This digital signal is converted into a video signal composed of a luminance signal and a color difference signal by the signal conversion unit 104 at the next stage, and is temporarily stored in the video memory 116 sequentially. When the video signal for one screen is recorded in the video memory 116, the video signal is sent to the encoding unit 108 in units of blocks of an arbitrary size, and is converted into encoded video data subjected to compression processing. The encoded video data is sent to the recording unit 113, and is recorded and stored on a removable recording medium such as a memory card.

[0004] Reproduction of video data on a recording medium is performed as follows.

The data on the recording medium is first read out to the memory 111 under the control of the CPU 106, and is sequentially sent to the encoding unit 108. The encoding unit 108 decompresses or decompresses the compression-encoded video data and converts it into a video signal composed of luminance and color difference signals. This video signal is converted by the RGB conversion unit 107 into a data format used by the display LCD 115, here the RGB format, and is sequentially converted into the VRAM 11.
2 is recorded. The signal on the VRAM 112 is sent to the LCD 115 at an arbitrary timing, and the reproduced video is displayed to the observer.

[0006] The photographed video data is transferred to an external device via the recording medium. On the external device side,
Using a driver to access this recording medium,
Performs data transfer, but if the recording format of the data on the medium is different from the external device and cannot be handled directly, the data format is converted simultaneously and the converted data is removable. Recording is performed on a medium or a recording medium in an external device.

[0007]

As described above, photographed video data is recorded on a removable recording medium. However, the recording format here is to increase the recording efficiency of the medium, and therefore, the versatility is increased. And was recorded using a high compression encoding method with a low compression rate. For this reason, it is necessary for the external device to perform a conversion process on the data on the medium, and the data can be used only by the external device having a driver or software capable of performing this process.
In addition, the encoded video signal must be decoded at the time of reproduction, and high-speed processing cannot be performed.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and makes it possible to easily read and reproduce photographed video data even in an information processing apparatus having different types of environments. An image pickup apparatus and a control method thereof are provided.

In order to solve this problem, for example, an imaging apparatus according to the present invention has the following configuration. That is, an imaging unit that converts a captured video into an electric signal, an encoding unit that performs a plurality of different encoding processes on video data captured by the imaging unit, and a plurality of encoding units that are obtained by the encoding unit. Control means for creating link data indicating the relevance of the encoded video data, and causing the plurality of encoded video data to be stored and held in a predetermined storage medium together with the link data.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 shows a block configuration of a photographing apparatus according to the embodiment. Hereinafter, each configuration will be described together with its operation.

An image photographed by the photographer is a lens 1
01, the image is formed on the image sensor 102 through the image sensor 1
The analog electric signal is converted into the electric signal by the photoelectric effect 02. This signal is converted into a digital signal by the A / D converter 103 at the next stage. The digital data is sequentially sent to the signal conversion unit 104, converted into a video signal including a luminance and color difference signal, and output to the video bus 105.

At the time when the photographer is performing framing for determining the subject to be photographed, the video signal is input from the video bus 105 to the RGB converter 107 for display and converted into an RGB format signal for display. Then, the data is output to the data bus 109 at the subsequent stage. The signal on the data bus 109 is
The data is recorded in the VRAM 112 under the control of the CPU 106, data is sent from the VRAM 112 to the LCD 115 at an arbitrary timing, and an image is displayed to the photographer.

When the photographer determines a subject and presses a shutter switch (not shown) on the operation unit 114 for recording, a recording operation of a video signal is started. A video signal (output signal of the signal conversion unit 104) composed of a luminance / color difference signal photographed at the time when the shutter switch is pressed can be recorded on a recording medium as it is. In order to record data, the encoding and compression processing is performed by the encoding unit 108 to reduce data redundancy and increase recording efficiency. For this encoding process, the video signal is temporarily recorded in the video memory 116.

When a certain amount of video data is recorded in the video memory 116, the video signal is transferred to the coding unit 108 under the control of the CPU 106, and the first coding process is started. In the first encoding processing, processing is performed using parameters such as a compression ratio and a video size desired by the photographer. The compression ratio and the like are based on the settings of a fine mode, a normal mode, and the like provided in a so-called device.

The encoding and compression processing for the video signal is, for example, a DCT based on the JPEG format.
(Discrete cosine transform) and Huffman transform.
The encoding and compression processing is started when the video signal composed of the luminance and color difference signals is recorded in the video memory 116 for one screen. The video signal is sent to the encoding unit 108. The luminance signal is 8 × 16 pixels and the color difference signal is 8 ×
The data is converted from raster scan to zigzag scan using eight pixels as a minimum unit and read from the video memory 116. Since the DCT and the Huffman transform are known per se, their description is omitted. The settings such as the compression ratio, the size of the video to be recorded, and the output data format required by the encoding unit 108 are changed from the values set by the photographer before the photographing to the CPU 106 when the shutter switch is pressed.
Is transmitted to the encoding unit 108.

When the video signal is input to the encoding unit 108, the video signal is sequentially subjected to encoding processing, sent to the data bus 109, and temporarily recorded in the memory 111 at the subsequent stage. The above processing is repeated, and the encoding processing of all video signals for one screen is performed. Before and after this processing, the CPU 106 generates a header / footer of an arbitrary format (for example, shooting date / time information) for the encoded video data, if necessary, and records it on the memory 111 together with the video data.

By the way, at the time when the above-mentioned first encoding processing is completed, the video signal data composed of the luminance and chrominance signals before the encoding processing is stored in the video memory 116 in the previous stage, and the photographer is stored in the memory 111 in the latter stage. Holds the first encoded data 303 that has been subjected to the encoding process using the parameters set by the user.

Then, when the first encoding process is completed,
The second encoding process is started again on the video signal data in the video memory 116 at the previous stage. The second encoding process is a process of converting a video signal in a format that is easy for the photographing apparatus to handle when reproducing and displaying a video, or that is required when video data is transferred to an external device. Here, a process is performed to generate video data in which a small image whose video size is thinned out compared to the data amount used in the first encoding process is converted into RGB format. In addition, it is also possible to add highly versatile encoding processing to reduce the data amount. In the second encoding process, parameters recorded in advance in the ROM 110 of the apparatus are stored in the CPU 106 regardless of the encoding parameters set by the photographer.
Are read, and based on this, the same video signal on which the first coding process has been performed is subjected to the coding process again.

In the second encoding process, first, the video memory 1
Under the control of the CPU 106, a video signal whose size is reduced is generated from the video signal held in the block 16 by using an arbitrary method such as interpolation. This signal is sequentially RGB
The data is sent to the conversion unit 107, converted from the luminance / color difference format to the RGB format, and temporarily recorded in the memory 111 at the subsequent stage. At this time, as in the case of the first encoding process, the CPU 106
Generates and records the header and footer of the RGB signal data as necessary.

When the second encoding process is completed, the video signal data composed of the luminance and chrominance signals before the encoding process is stored in the video memory 116 at the previous stage, and the parameters set by the photographer are stored in the memory 111 at the subsequent stage. , And second encoded data 304 that has been subjected to a second encoding process in a predetermined format. After that, using the same video signal and changing only the compression ratio at the time of encoding,
Although it is possible to generate the n-th encoded data in the n-th encoding format, such as the one obtained by encoding only the luminance information, the encoded data in the above two formats is stored in the recording unit 113 here.
Record on the removable media above.

At the time of recording, the CPU 106 generates link data indicating the relationship between the two encoded data before recording the two encoded data on the memory 111 on the recording medium in the recording unit 113, and Record above. The two encoded data and link data are recorded on a recording medium in the recording unit 113 in a format shown in FIG. 3 which can be read by an assumed external device. In this case, the second encoded data 304 is recorded while being positioned as thumbnail data which is a data amount reduced version of the first encoded data 303. After recording the data, the data in the previous and next memories is discarded in preparation for the next photographing, and the framing operation is returned again.

Incidentally, the recording medium in the embodiment may be any kind of memory card, magnetic disk (hard disk or the like), magnetic tape or the like.

The above-described processing is achieved by the control and execution of the CPU 106. This program is stored in the ROM 110, and is organized as shown in FIG. It should be noted that the flowchart in FIG. 7 is a process when the shutter switch of the operation unit 114 is operated.

First, in step S 1, digital data of luminance and color difference for one screen obtained from the signal conversion unit 104 is stored in the video memory 116. Next, the process proceeds to step S2, where parameters corresponding to the mode (for example, fine mode or normal mode) designated by the operation unit 114 are read from the ROM 110, set in the encoding unit 108, and stored in the video memory 116 in units of predetermined blocks. The data is transferred to the encoding unit 108 to perform encoding. As described above, in the embodiment, DCT (Discrete Cosine Transform) based on the JPEG format and Huff
Man conversion will be performed. The encoded data thus obtained is temporarily stored in the memory 111 as first encoded data (step S3).

Next, the process proceeds to step S4, in which the luminance data and the color difference data are decimated and read from the video memory 116, and the RGB conversion unit 107 creates the data in the RGB format. In step S5, the generated data is converted into the second data. The data is stored in the memory 111 as encoded data.

Thereafter, in step S6, link data of the two encoded data stored in the memory 111 is generated as described above, and in step S7, the removable storage finally mounted on the recording unit 113 is generated. It is stored and saved on a medium.

Next, processing for reproducing the video data 301 recorded on the recording medium will be described. In displaying the recorded video, the second encoded data 304 recorded in the RGB format is used here as it is. When an instruction to display an arbitrary video recorded by the photographer is input from the operation unit 114, the CPU 106 searches for the specified video data on the recording medium, and stores the second encoded data 304 therein into the memory 111. Read on. If the number of pixels of the second encoded data 304 matches the number of pixels required by the display LCD 115, the data on the memory 111 is rearranged so that the RGB pixels of the LCD 115 match the order. Then, the data is recorded in the VRAM 112, and the data is transferred and displayed from the VRAM 112 to the LCD 115 at an arbitrary timing. If the number of pixels of the second encoded data 304 does not match the number of pixels required by the display LCD 115, the CPU 106 enlarges / enlarges the encoded data.
After performing interpolation processing for reduction, recording is performed on the VRAM 112 and video is displayed on the LCD 115. If the second encoded data 304 has been subjected to some compression processing,
After the CPU 106 expands or decompresses the encoded data, a similar process is performed to display an image.

In this case, since the second coded data 304 has a smaller image size than the first coded data 303, the display processing can be performed quickly and the memory area to be used is small, so that the memory It is also possible to reduce the size of 111.

Next, a process for transferring the recorded video data 301 via a removable recording medium to an external device, in this case, a computer running an arbitrary OS will be described. When data is transferred from a recording medium to a computer, the amount of information required for one data file may differ depending on the OS. For example, one OS can read video data alone, while another OS can read video data alone. In addition to the data, data indicating the association with the data for icons and thumbnails and the application is required. With respect to such a difference between OSs, the first and second encoded data are made to correspond to data required by each OS, so that subsequent processing can be made unnecessary.
In this case, in an OS that can be captured by video data alone, two pieces of information of the first and second encoded data can be used as video data. By pre-recording in such a format on a recording medium, there is no need to use an extra driver or application when capturing data, so that data transfer can be easily realized and a highly versatile recording medium can be used. Can be used.

According to the present embodiment as described above,
Displaying the same video data in this storage medium by storing the captured video data in a storage medium as two types of data, versatile data and data convenient for the device itself, or more The user only needs to read and display any of the video data, and does not need a dedicated driver or the like.

In the above embodiment, the video memory 11
After the video data is stored in No. 6, the first encoding and the second encoding are processed in this order. However, this order may be reversed. May be performed. This is because all of these processes are performed on the data stored in the video memory 116.

In the above-described embodiment, the data in the recording unit 113 is described as being detachable. However, for example, a communication interface is provided, and encoded data in a specified format is transmitted to a higher-level device connected to the communication interface. You may transfer it.

In this case, in accordance with a predetermined instruction from the higher-level device, means for transmitting the stored data list, and in accordance with the instruction indicating the data format to be transferred, the data of the corresponding format in the designated data It is sufficient to provide a means for transferring

<Second Embodiment> Next, a second embodiment will be described.

In the second embodiment, an example is shown in which a single image sensor can cope with moving images and still images simultaneously. FIG. 4 shows a block configuration of a photographing apparatus according to the second embodiment.

First, a captured image is formed on an image sensor 102 through a lens 101, and is converted into an analog electric signal by the photoelectric effect of the image sensor 102. This signal is converted into a digital signal by the A / D converter 103 at the next stage. The digital data is sequentially sent to the signal conversion unit 104, converted into a video signal including a luminance and color difference signal, and output to the video bus 105. The signal on the video bus 105 is sent to the RGB conversion unit 107 under the control of the CPU 106, is converted into the RGB format, is sequentially recorded in the VRAM 112, and is output from the VRAM 112 at an arbitrary timing.
The data is sent to the CD 115, and the photographed video is displayed to the photographer. At the time of recording, when a photographer presses a moving image recording switch and a still image recording switch (not shown) on the operation unit 114, a moving image and a still image can be distinguished and recorded simultaneously. This process will be described below separately for a moving image and a still image.

First, in the case of shooting a moving image, signals on the video bus 105 are sequentially sent to the first encoding unit 401.
Here, the video signal composed of the luminance and the chrominance is subjected to conversion (DCT and Huffman conversion) for recording in the JPEG format, as described in the first embodiment. The first encoding unit 401 is provided with a dedicated memory 402 for performing block conversion (zigzag scan) on a signal input in a raster format from the video bus 105, and data that flows sequentially has a certain size. The following images can be encoded without any time loss. The size of the image to be recorded is set in advance by the photographer, but when recording a moving image, the size is set within a range in which the size of the image is restricted. Therefore, the first encoding unit 401 captures only data in a necessary area from the data flowing through the video bus 105.

In order to achieve real-time encoding and recording, the compression ratio of the video signal is set high in advance. The moving image data output from the first encoding unit 401 after being subjected to the real-time encoding process is directly recorded on a recording medium in the recording unit 113 in a moving image format under the control of the CPU 106. Before and after recording
If necessary, the CPU 106 generates a header and a footer of the moving image data and records them at an arbitrary position in association with the moving image data to be recorded. During recording of a moving image, the signal on the image bus 105 is simultaneously sent to the RGB conversion unit 107, and the image being photographed is displayed to the photographer in real time.

Next, recording of a still image will be described. When the photographer presses the still image recording switch provided on the operation unit 114, first, the luminance and brightness on the video bus 105 are stored in the dedicated memory 404 connected to the second encoding unit 403.
A video signal composed of a color difference signal is taken in for one screen, starting at an arbitrary timing. The magnitude of the video signal at this time is set in advance by the photographer as in the case of shooting a moving image. However, in still image recording, as described above, all of the video signals are stored in the memory 404 before the video signal is encoded. No real-time processing is required for capturing, so the size of the video can be freely selected below the size of the image sensor 102 used or the capacity of the dedicated memory. The video signal recorded in the memory 404 is subjected to conversion for recording in the same JPEG format as in the first encoding unit 401 in the second encoding unit 403 here, but also in real time, unlike moving image shooting. Since it is not necessary to transfer and record data in the first encoding unit 401, the compression ratio can be lower than that set in the first encoding unit 401, and a video signal with high image quality can be performed. The still image data converted by the second encoding unit 403 is
Under the control of a memory control unit 406 different from 106, the data is temporarily recorded in the dual port memory 405.

If the still image recording operation does not occur at the same time as the moving image recording operation, the CPU 1 immediately starts recording on the medium.
The recording operation is performed under the control of 06. First, the encoded still image data is transferred to the memory 11 via the data bus 109.
1 is recorded. This still image data is added to the CPU 106
Generates the necessary header and footer and records them on the recording medium as one data file.

The processing when the still image recording operation is performed simultaneously with the moving image recording operation is as follows. The memory control unit 406 does not output the still image data onto the data bus 109 until the moving image shooting ends, and enters a standby state. If still image shooting is performed during this time, still image data is sequentially recorded up to the limit of the capacity of the dual port memory 405. When the dual port memory 405 is full, no further recording is accepted. After the moving image recording is completed, the memory control unit 406 requests the CPU 106 to record the still image data, and passes the subsequent processing to the CPU 106. When a plurality of still image data exist in the dual port memory 405, the CPU 106 sequentially generates a header and a footer and records them on a recording medium. At this time, link data indicating the relevance to a series of moving images is generated and recorded together. During the still image recording, it is possible to simultaneously generate small image data for displaying on the LCD 115 or for thumbnails having different compression ratios and image sizes as described in the first embodiment.

If the still image recording process does not occur at the same time during the recording of the moving image, the CPU 106 can also generate the small image data for display on the LCD 115 or the thumbnail for the moving image at an arbitrary timing. It is. Also in this case, as described above, link data indicating the relevance to a series of moving images is simultaneously generated and recorded.

As described above, in the second embodiment, even when there is only one image pickup device for photographing a video, moving images and still images of different encoding systems are encoded from the same video signal. Records can be made.

The present invention can be applied to a system including a plurality of devices (for example, a camera and a recording unit).
The present invention may be applied to a device including one device (for example, a digital camera device).

Another object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or apparatus, and to provide a computer (or CPU) of the system or apparatus.
And MPU) read and execute the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

As a storage medium for supplying the program code, for example, a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer based on the instruction of the program code. ) May perform some or all of the actual processing, and the processing may realize the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that the CPU included in the function expansion board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

As described above, according to the photographing apparatus of the embodiment, a plurality of coded video data having different coding conditions are generated from the same video signal at the time of photographing, so that the photographic apparatus can be used in the photographing apparatus. Can be reduced, and high-speed internal processing can be realized, and user operability can be improved.

Further, even when data is transferred to an external device after being recorded on a recording medium, a special driver such as a dedicated driver is provided because data transfer can be easily performed without requiring special processing such as data conversion. Data can be transferred even to an external device that is not connected, and a highly versatile method of using a recording medium can be realized.

[0053]

As described above, according to the present invention, photographed video data can be easily read and reproduced by an information processing apparatus having different types of environments.

[0054]

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a block diagram showing a conventional example.

FIG. 3 is a diagram illustrating a relationship between first and second encoded data and link data according to the first embodiment.

FIG. 4 is a block diagram showing a first embodiment of the present invention.

FIG. 5 is a flowchart illustrating an operation processing procedure according to the first embodiment.

[Explanation of symbols]

 Reference Signs List 101 lens 102 imaging device 103 A / D converter 104 signal conversion unit 105 video bus 106 CPU 107 RGB conversion unit 108 encoding unit 109 data bus 110 ROM 111 memory 112 VRAM 113 recording unit 114 operation unit 115 LCD 116 video memory

Claims (11)

[Claims] An imaging unit configured to convert a captured video into an electric signal; an encoding unit performing a plurality of different encoding processes on video data captured by the imaging unit; And a control unit for creating link data indicating a relationship between the plurality of encoded video data and storing and holding the plurality of encoded video data in a predetermined storage medium together with the link data. . 2. The imaging apparatus according to claim 1, wherein the plurality of encoding processes are processes for making the code amounts of the video data different from each other. 3. The apparatus according to claim 2, wherein said encoding means performs JPEG encoding. 4. The imaging device according to claim 1, wherein the encoding unit thins out video data stored in the storage medium to generate RGB format data. 5. The photographing apparatus according to claim 1, wherein the storage medium is detachable from the apparatus. 6. The storage device according to claim 1, further comprising storage means for storing video data imaged by said imaging means, and supplying the stored video data to said encoding means. An imaging device according to any one of the above. 7. A display unit for displaying an image obtained by the imaging unit, and a generation unit for generating data in a format that can be displayed on the display unit based on video data imaged by the imaging unit. The imaging device according to any one of claims 1 to 6, further comprising: 8. An image processing apparatus, further comprising: an instruction unit for instructing that image data captured by the imaging unit be stored on the storage medium, wherein the storage unit, the encoding unit, and the control unit include the instruction unit. 7. The image pickup apparatus according to claim 6, wherein the apparatus operates when an instruction from the means is given. 9. The instruction by the instruction means includes a moving image storage / holding instruction and a still image storage / holding instruction. When the moving image storage / holding instruction is issued, the compression ratio is higher than in the case of still image storage / holding. 9. The imaging apparatus according to claim 8, wherein the video data is stored and held in the storage medium by using an encoding that becomes: 10. When the still image storage / holding instruction is issued by the instructing means and the moving image storage / holding operation is being performed, the process waits, and when the moving image storage / holding operation is completed, The imaging device according to claim 9, wherein the image data is stored in a storage medium. 11. An imaging step of converting a captured video into an electric signal, and a control step of storing and holding a plurality of encoded video data different from the video data captured in the imaging step in a predetermined storage medium. A method for controlling an imaging device, comprising: