JPH07255030A - Recording and reproducing device for compressed image - Google Patents

Abstract

PURPOSE:To provide an image recording and reproducing device which makes a compression ratio display of digital compressed images or display them in compression order on a monitor in single-picture mode and also displays the digital compressed images as multiple images on a monitor in the compression order. CONSTITUTION:The reproducing device for images which are compressed and recorded on a memory card 11 reads image information out of the memory card 11 by an S/M/C part (system/memory/control part) 12 and decompresses the information to an image through respective circuit parts 9, 14, 15, and 16 with the control signal of the S/M/C part 12 based on information that a user sets at a display mode control part 21. The decompressed image is recorded in a memory part 17 in order, and the image signal is read out and converted from digital to analog to generate compression ratio corresponding to the video signal by an OSDC part 19, and this signal is added to the video signal to display a single picture on the monitor 20 in the compression order or reduced screens in multi-screen mode in the compression order.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image signal recording / compressing / decompressing / reproducing apparatus, and particularly, when reproducing a compressed image on a CRT screen, the compression ratio is superimposed and displayed on each photographed image, or in the order of compression ratio. The present invention relates to a compressed image recording / reproducing apparatus that displays each captured image as a single image or multiple images.

[0002]

2. Description of the Related Art In the case of digitally recording an image taken by a conventional digital still video camera (hereinafter referred to as DSVC) or the like on a recording medium such as a memory card, the capacity of the recording device is taken into consideration and the data of the image signal is reduced in capacity. It is necessary to compress. As a method of compressing such image data, for example, JPEG (Joint Photogr) is used.
The apic Expert Group algorithm is known. The image reproduction of the compressed image uses the JPEG inverse algorithm.

Therefore, this compression / expansion algorithm will be briefly described. The image of the image signal is divided into a predetermined number of blocks (8 * 8 pixel block division), and the data of each pixel in each divided block is orthogonally transformed (DCT; Dis).
create Cine Transform).

The converted data (image signal) is converted into DC component (low frequency component) and AC component (high frequency component) coefficients, and quantization suitable for each component is performed using a quantization table ( This quantization table is the source that controls the image quality and the amount of coded information).

After quantization, both DC / AC components are entropy coded and digitally recorded on a storage medium such as a memory card. In reproduction, a technique has been established in which the encoded signal read from the storage medium is inversely transformed (inverse quantization, inverse DCT) to obtain the original signal and the image is displayed on the CRT.

Based on this technology, for example, Japanese Patent Laid-Open No. 1-21989
No. [compressing and recording apparatus for image signals and decompressing and reproducing apparatus] have been proposed. The content of this proposal is another improvement proposal of Japanese Patent Application Laid-Open No. 61-135286, which is a device capable of changing the compression ratio of image data, and selects a compression ratio when the DCT-converted image data is compression-encoded. The image data compressed by the selected compression ratio and the compression ratio data are written in different areas of the recording medium.

Further, in reproduction, a technique has been proposed in which compression ratio selection data and compression-encoded image data are read from a recording medium, and compressed image data is decompressed and decoded using the compression ratio selection data.

[0008]

However, in the prior art, as seen in JP-A 1-2221989,
A method of compressing and decompressing (encoding and decoding) a captured image has been discussed, and a point concerning a compression ratio display and a display system in reproducing and displaying a compressed image has not been disclosed.

Recently, there have been many opportunities to view compressed digital replay images shot by DSVC, but it is unclear how much the replay image is a replay image compressed. For example, when a photographer shoots a subject at a later date on a monitor. When you want to know the compression ratio of, there is a problem that you do not know the contents. Furthermore, when trying to compare and examine replay images shot with the same subject with different compression ratios, it would be very inconvenient without the compression ratio display function, and the photographer would have to reduce the compression ratio when shooting. is there. Further, when it is intended to perform image editing centered on the compression rate, for example, multi-image comparison editing of images having the same compression rate or rearrangement of the same images in the compression rate order, such editing cannot be performed immediately.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems of the prior art, in which a subject signal is image-compressed and recorded, and at the same time compression rate information corresponding to the compressed image is stored in a storage medium. And a reproducing means for reading the compressed image and the compression rate information recorded in the storage medium and displaying the compressed image and the compression rate on the reproduction screen at the same time. A recording / reproducing apparatus for compressed images is proposed.

Further, there is provided means for reading the compression information recorded in the storage medium in advance at the time of reproducing the compressed image and reproducing the compressed image in the order of the compression ratio.

Further, when the compressed image is reproduced, the compression information recorded in the storage medium is read in advance, the compressed images are written in the memory in the order of the compression ratio, and the compression ratio is displayed on the compressed image reproduction screen of the single image or the multi-image. Display at the same time.

For example, when shooting a subject with a DSVC camera, the camera is provided with a compression ratio selection mode (manual, auto, fixed, etc., each having several to ten or more types of compression quantization tables), which is selected to select a compressed image and a compressed image. Means for recording information such as a rate on a recording medium, such as a memory card, is provided, and those images and image information are recorded. During reproduction, a means for pre-reading and storing the image information of the recorded image, such as the compression rate and the image recording address information, from the recording medium is provided so that the photographer can take the captured image in the order of low compression rate (or high compression rate). In order to reproduce one screen at a time, the reproducing apparatus having means for sequentially reading the image signals corresponding to the respective compression ratios directly from the recording medium using the recorded image information read in advance and decoding and reproducing the image signals is provided. provide. If you want to display multiple images in ascending order of compression rate (or in order of higher compression rate), use the recorded image information that was read in advance, and sequentially select (compression rate order) from the recording medium to read out the image signal and decode it for playback. The present invention provides a device having means for recording a multi-image (for example, 25 screens) in a memory and means for reproducing the image recorded in the memory. And if the photographer wants to know the compression ratio of the playback image and wants to display the compression ratio on a part of the captured image, select the compression ratio display code with a button etc. to compress each captured image in single-screen display or multi-screen display. And means for displaying the rate.

[0014]

According to the circuit configuration means of the present invention, in the expansion and reproduction of the compressed and recorded image, the compression ratios of the reproduced images can be simultaneously displayed, and the images can be reproduced in the order of the compression ratios so that the images of different compression ratios can be the same. The image quality comparison and evaluation of images can be easily performed sequentially on the CRT.

Further, comparative evaluation of reproduced images having different compression rates can be easily carried out.

Furthermore, since multiple images can be reproduced in order of compression rate, it is possible to easily perform image editing and image comparison and examination based on this display.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing an image signal compression recording apparatus according to an embodiment of the present invention, and FIGS. 2 and 3 are schematic configuration diagrams of an image signal expansion / reproduction apparatus according to another embodiment. FIG. 4 shows an example in which the compression rate is displayed on the monitor.
3 shows a single image and compression rate on the monitor.
Is an example of displaying a multi-image and a compression rate on the monitor.
In the following figures, the same parts are designated by the same reference numerals.

Next, the compression / expansion operation of the image signal will be described with reference to FIGS. FIG. 1 shows an embodiment of an image compression apparatus related to the compression ratio display, and the shutter, AF mechanism, gamma correction circuit, white balance circuit, etc., which are parts of the camera that are not particularly related to the explanation of the operation, are omitted.

In FIG. 1, the subject light that has passed through the lens 1 enters the image pickup device 2 after passing through a diaphragm (not shown). The subject image incident on the imaging device 2 is converted from an optical signal to a video electric signal. The video signal converted into an electric signal is amplified into an electric signal of a predetermined size by an amplifier circuit 3 and a luminance signal 4 (the luminance signal is hereinafter referred to as a Y signal),
It is separated into Y and C signals by a color signal (color signal is hereinafter referred to as C signal) separation unit and is input to five A / D conversion units. The A / D converter converts the Y and C signals from analog signals into digital signals.

The color signals (Y, C) converted into digital signals enter the blocking unit 6 and, for example, 8 × 8 = 6.
It is divided into blocks of 4 pixels. The image signal blocked by the blocking unit 6 is orthogonally transformed (orthogonal transform is herein referred to as cosine transform, hereinafter referred to as DCT transform).
It is input to the section 7. The orthogonal transformation unit 7 performs orthogonal transformation for each block. Then, the orthogonally transformed signal is sent to the compression encoding unit 8. The compression encoding section 8 receives an image from a signal sent from the compression rate selection ROM table section 9 (the compression rate selection ROM table section 9 is also called a quantization table, which is data for determining the compression rate of the source image). Encode the data. As the compression rate selection ROM table data 9 to be encoded, some kinds of compression data having an optimum compression rate are prepared in advance in advance in ROM according to the characteristics (picture or the like) of a captured image. If the photographer selects the compression rate with the mode setting button 13 before shooting the subject, this signal enters the system / memory / control section (hereinafter referred to as S / M / C section) 12, and the compression rate selection ROM table section Select 9 data. That is, one of the data in the compression rate selection ROM table section 9 corresponding to the compression setting content set by the mode setting button 13 is selected and the image signal is encoded. As the encoded data, the image compression data, the image compression rate data, and other data (for example, color or monochrome, frame or field, etc.) are recorded in the memory card 11. The S / M / C unit 12 is a control circuit that controls each function of the DSVC, and receives a signal from the amplifier circuit 3 to generate various synchronization signals. The control signal is also output to each of the A / D conversion unit 5, the blocking unit 6, the orthogonal transformation unit 7, the compression ratio selection ROM table unit 9, and the compression encoding unit 8. Further, the S / M / C unit 12 sends a control signal for recording an image to the connector unit 10, and the data compression-encoded by the compression encoding unit 8 is written in the memory.

2 and 3 show an embodiment of the present invention for decoding and reproducing a signal in which a compressed image recorded in the memory card 11 and data accompanying the image data are written, and FIG. 3 is shown in FIG. This is an example in which the memory unit 17 is added.

Next, the operation of this reproducing apparatus will be described. When the memory card 11 is connected to the card connector section 10 and the general reproduction mode is selected by the display mode control section 21, a control signal from the system / memory / control section (hereinafter referred to as S / M / C section) 12 causes The image data in the memory card 11 is searched and S / M / C
The CPU in the unit 12 analyzes the data. Based on this analysis result, the compressed image signal and other data are output from the memory card 11 in synchronization with the control signal of the S / M / C unit 12 and input to the decompression decoding unit 14. Next, a signal corresponding to the previously analyzed data is given from the S / M / C section 12 to the compression rate selection ROM table section 9, and the compression rate data set at the time of shooting is given to the decompression decoding section 14 for decoding. Get the data.

The decoded data is subjected to orthogonal inverse transform in the orthogonal inverse transform unit 15. The orthogonally inversely transformed block data are input to the block synthesizing unit 16 and the block data are synthesized.

Here, in FIG. 3, each block composite data is once written in the memory unit 17.

After that, the memory writing image in the memory section 17 is sequentially read by the memory reading signal from the S / M / C section 12, and enters the D / A converting section 18 to be converted into an analog image signal. OSDC for this analog image signal
Section (OSDC section is a circuit configuration that superimposes on the image signal and carries another information signal. Here, the OSDC section for analog signal is used.
Although it is a circuit, a digital OSDC circuit configuration may be used. ) The output signal of 19 is superimposed, and the image display monitor 20
The reproduced image can be viewed on the image monitor 20. The S / M / C unit 12 is a control unit that controls each function of the reproducing device, and includes a compression rate selection ROM table unit 9, a decompression decoding unit 14, an orthogonal inverse transformation unit 15, and a block synthesis unit 1.
6, memory unit 17, D / A conversion unit 18, OSDC unit 19
A control signal is input / output to / from each to control the operation of each unit. Further, the S / M / C unit 12 sends a write / read signal to the memory card unit 11 to control the memory data. The S / M / C unit 12 analyzes the image display control signal received from the display mode control unit 21,
What kind of reproduced image is displayed on the image display monitor 20 is sent to each functional circuit section by signal control suitable for the content.

Next, the compression rate display operation of the reproduced compressed image will be described with reference to FIGS. In the figure, 23 is an embodiment in which a single compressed image is also displayed on the monitor at the same time, and 24 is a multi-image display of 25 screens with the compression ratio display (an example in which 25 screens are displayed on the monitor in the order of photographing a subject). ) This is an example displayed on a monitor.

As described with reference to FIG. 1, the photographer with the DSVC has the mode setting button 13 before photographing the subject.
After setting the compression rate of the image automatically or manually (Automatic is a system that automatically determines the compression rate according to image quality, manual is a system that determines the compression rate each time according to the subject taken by the user), When shooting and playing back a subject, the person who tries to play it back (hereinafter called the player)
With respect to reproduction, operations such as selection of simple screen reproduction or multi-screen reproduction (selection of the number of multi-screens), selection of presence / absence of compression ratio display, selection of other data display, etc. are operated by keys on the display control unit 21. As a result, the S / M / C unit 12 operates and a display corresponding to the input condition is displayed on the monitor 20.

Next, the compression rate display operation of the compressed image will be described with reference to FIG. When the player reproduces the digital compressed image, the player connects the memory card 11 in which the digital image is recorded to the connector unit 10. Next, the main SW of the playback device (not shown) is turned on. Under this condition, the player uses the display mode control unit 21 to select the playback mode of step A21 and set the playback method to A.
Determined in 21 steps.

That is, in step A20, the presence or absence of a memory medium is detected, and the process branches to a step of issuing some warning that reproduction cannot be performed without the memory card 11. If the detection is OK, the reproduction mode of A21 step (reproduction mode) is set, and in A22 step, it is selected whether or not the reproduced image is a single screen. If it is a single screen, the process proceeds to the next A26 compression rate display step. If it is not the single screen display, the process proceeds to the multi-screen display of step A23.

Here, in the case of the single image compression rate display in step A26, the content of the compression rate selection ROM table is S / M /
The C section 12 analyzes the compression rate, outputs display data corresponding to the content to the OSDC circuit 15, and adds the compression rate data to the analog signal output from the D / A conversion section 18 (step A27). ), The image is displayed on the monitor (A28 step).

Next, in the case of multi-image display (step A23), the number of multi-image displays is then selected (step A24), and a predetermined multi-image display is performed.

Next, the compression rate reproduction display of compressed images according to another embodiment, that is, single image reproduction display and multi-image reproduction display operation will be described with reference to FIGS. The simple reproduction (reproduction of compressed images in the order of recording) and multi-display reproduction (screen display according to the shooting order by selecting the number of multi-image displays, for example, 25 screens or 50 screens) have been described in the previous embodiment. Here, the simple reproduction in which the compression rate is rearranged and the multi-image redisplay in which the compression rate is rearranged will be mainly described with reference to the flowchart of FIG.

It is assumed that the memory card is connected to the reproducing apparatus and the reproducing apparatus is powered on before step A1.

First, a simple single image reproduction in the order of compression ratio (2 in FIG. 5)
7 shows an example of this). That is, when the user selects the compression rate simple single-image reproduction mode in step A1 (mode selection), the presence or absence of the memory medium is detected in step A2 (memory medium), and some warning that reproduction cannot be performed without the memory card 11 is given. Branch to the step of issuing. If detection is OK, the playback mode is A3 step, and A4
In step (image data search), a control signal for reading the contents of the memory card 11 is output from the S / M / C unit 12 and the number of recorded sheets,
The CPU in the S / M / C unit 12 reads the information such as the compression rate and the fields / frames. Next, the player inputs the compression rate order display signal (the order of low compression rate or the order of high compression rate) in step A5. For example, in this case, if a mode for reproducing in ascending order of compression ratio is selected, single image reproduction (Y) of step A6 is selected, and the process proceeds to general reproduction of the next step A7. A7 (N) is selected and the process proceeds to the reproduction in the compression ratio order of A12. Based on the condition selected in the A5 step, the images are read from the memory card first so that the images are reproduced in the descending compression ratio in the A13 step (memory address processing). 12 information
The CPU is re-processed, the memory addresses are read out in the ascending compression ratio, and the first reproduced image is recorded in the memory unit 17. Next, step A8 is entered to decide whether or not to display the compression rate. This compression ratio display presence / absence signal may be an interrupt signal during image display, or may be previously set in step A5 or A1.
You may decide in steps. When an interrupt signal in this case (for example, an interrupt signal by remote control operation) is input as a compression rate display signal by remote control operation, the compression rate data output preparation is performed by ID display processing of A9 (ID display processing).

Next, in the reproduction processing step A10 (reproduction processing), at the same time, the signal recorded in the memory unit 17 is
An analog signal is reproduced by the D / A converter 18, compression rate data is added to the reproduced image, and the image is displayed on the monitor. That is, in FIG. 3, the S / M / C unit 12 and the OSDC unit 19
Outputs the compression rate corresponding to the reproduced image, and the D / A converter 18
Is added to the output and the reproduced image can be viewed on the image display monitor 20. Reference numeral 28 in FIG. 5 is another embodiment, which is an example of a forward reproduction with a high compression rate in a compression rate order simple single-image reproduction. This display method can also be easily implemented by adding software as in the above embodiment.

Next, the multi-image reproduction in order of compression ratio (2 in FIG. 5)
(Shown in FIG. 5) will be described.

When the player selects the compression ratio multi-image reproduction mode in step A1, the presence or absence of the memory medium is detected in step A2 and a warning is issued to the effect that reproduction cannot be performed without 11 cards (here To processing function)
Branch to. If the detection is OK, the reproduction mode of the A3 step is entered, and the control signal for reading the memory contents is output from the S / M / C section 12 in the A4 step, and information such as the number of recorded images, the compression ratio, and the field / frame is displayed in the S / M / The CPU in the C section 12 reads it. Next, in step A5, the player inputs the compression rate order display signal (the order in which the compression rate order is low or the order is high) and the compressed image display number. For example, in this case, an embodiment will be shown in which the player selects the 25-screen multi-image reproduction mode in the ascending compression order.

As a result of the selection of A5, from the A6 step (N) branch, the A14 step (multi-image reproduction) is entered and the multi-display is recognized. Judge that it is reproduction. (If it is not a multi-image reproduction, the process proceeds to A14 step (N) branch to another processing function.) By this process judgment, the process proceeds to A16 (memory address process), A17 (memory writing process), and A18 (multi-image number), and the compression rate. The recorded images are read out from the memory card 11 in the order of ascending image, and pictures for 25 screens are sequentially recorded in the memory section 17 of FIG. And 25
When the screen is full of memory, the process proceeds to the A8 compression rate display step.

This flow (steps A15 to A18) will be described with reference to the circuit block of FIG. 3. First, in step A4 (image data search), S / M /
Under the condition that the C section 12 grasps the contents of the memory card 11 in advance by the memory card 11 and the connector section 10 and displays them in the order of multi-image and low compression rate, S /
The address of the recorded image in the order of lower compression rate than the image information stored in the M / C unit 12 is arithmetically processed in 12 and sequentially read out from the memory card 11, and the decompression / decompression unit 1
4, compression rate selection ROM table section 9, orthogonal inverse transformation section 1
5. The block synthesizing unit 16 and the image reproduction processing are S / M / C.
It is implemented by receiving the control signal of the unit 12. This reproduced image is further stored in the memory unit 17 by another control signal in 12
, The digital image signals sequentially subjected to block synthesis are thinned out and recorded. Now, when further entering A8 (compression ratio display) step, it is whether or not to display the compression ratio. The compression ratio display presence / absence signal may be an interrupt signal during image display, or may be determined in advance in A1 step or A5 step. In this description, when an interrupt signal (interrupt signal by remote control operation) is input by remote control operation, it is compressed into a reproduced image in the ID display processing of A9 (ID display processing) and the reproduction processing step of A10 (reproduction processing). The rate display image is added and the image is displayed on the monitor.

That is, referring to FIG. 2, S / M / C
By the image information stored in the unit 12 and various arithmetic processing,
Where in the memory the image with low compression ratio is located, the compression ratio of the image, the number of multi-image display, the selection of the thinning clock for recording the composite image in the memory, etc. Decide S / M / based on these information
The C unit 12 outputs the compression rate value corresponding to each reproduced image to the OSDC unit 19, and the output value and the reproduced image output converted from the digital signal to the analog signal by the D / A conversion unit 18 are added to form a composite signal. The processed or component signal-processed signal (this processing circuit not shown) is connected to the image display monitor 20. As a result, a multi-image 25 screen, a compression ratio low order, and a compression ratio value display reproduction image can be viewed on the monitor. . This display situation is shown in FIG.
Is a multi-screen (monitor). The embodiment of 26 in FIG. 5 is a method of displaying a multi-image in the descending order of compression ratio, and can be easily implemented by adding software as in the above embodiment.

[0041]

As described above, according to the structure of the present invention, the compression rate at the time of photographing a subject can be easily known.

Further, it is possible to sequentially display a single image in the order of high or low compression ratio of the digital compressed image, and to display multiple images in the order of high or low compression ratio in the multi-image display of the digital compressed image.

Furthermore, it is possible to easily evaluate the image quality of images obtained by shooting the same subject with different compression ratios, and to evaluate the image quality when the subjects have different compression ratios in single image sequential display or multi-image display.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a digital compressed image recording apparatus of the present invention.

FIG. 2 is a schematic configuration diagram of a digital compressed image reproducing device showing an embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a digital compressed image reproducing apparatus showing another embodiment of the present invention.

FIG. 4 is a schematic diagram of a compression ratio display example for explaining an embodiment of the present invention.

FIG. 5 is a schematic view of an example of image display in order of compression ratio for explaining another embodiment of the present invention.

FIG. 6 is a compression ratio display flowchart illustrating an embodiment of the present invention.

FIG. 7 is a flowchart for displaying images in order of compression ratio for explaining another embodiment of the present invention.

[Explanation of symbols]

1 lens part 2 imaging device part 3
Amplification unit 4 Y / C separation unit 5 A / D conversion unit 6
Blocking unit 7 Orthogonal transform unit 8 Compression coding unit 9 Compression rate selection ROM table unit 10
Connector part 11 Memory card 12 System / memory / control part 13 Mode setting button 14 Decompression / decoding part 15
Orthogonal inverse transformation unit 16 Block synthesis unit 17 Memory unit 18
D / A converter 19 OSDC 20 Image display monitor 21
Display mode control section 22 Monitor 23 Single screen display monitor figure 24, 25, 26 25 screen multi display monitor figure 27, 28 Single screen display monitor figure

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location H04N 7/30 H04N 7/133 Z

Claims (3)

[Claims] 1. A recording means for image-compressing and recording a subject signal and simultaneously recording compression rate information corresponding to the compressed image in a storage medium, and the compressed image and compression rate information recorded in the storage medium. A compressed image recording / reproducing apparatus comprising: a reproducing unit for reading and displaying the compressed image and the compression rate on a reproduction screen at the same time. 2. A compressed image reproducing apparatus comprising means for reading in advance compression information already recorded in a storage medium when reproducing a compressed image, and reproducing the compressed image in the order of compression ratio. 3. When reproducing a compressed image, the compression information recorded in the storage medium is read in advance, the compressed images are written in a memory in the order of compression ratio, and the compression ratio is displayed on the compressed image reproduction screen of the single image or multi-image. 3. The compressed image recording / reproducing device according to claim 1, wherein the compressed image is displayed at the same time.