JPH0918884A - Moving image compression and reproduction system and method and moving image radio signal transmission and reception system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the capacity of a frame memory and also to reduce the computing volume in a compression/reproduction mode by applying the halftone processing to a gradation image and reducing the quantity of data on a moving image. SOLUTION: An image segmentation part 11 of a movement detection/extraction means 10 detects the information on the movement area included in a gradation moving image supplied via an input terminal 1 and segments this image. A subtracter 12 subtracts the information on a reference image from the supplied image information to obtain a differential component. A movement decision part 13 detects the movement component based on the differential output of the subtracter 12. An image encoding means 20 inputs and processes a gradation image to outputs an encoded binary image. A reference image generation means 30 processes the data on only the movement information on every frame based on the correlation among the inter-frame movements of the moving image and also transmits the processed data. At the same time, the means 20 binarizes the gradation image based on the minimum data on only the movement information on the moving image and outputs this binary image.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving image compression / reproduction system and method, and a moving image wireless signal transmission / reception system, and in particular, when transmitting a moving image signal, the density of an image is set to, for example, 2 by a predetermined threshold value for each pixel. The present invention relates to a moving image compression / reproduction system in which halftone processing for converting low-gradation image data of about four or four values is performed on moving image data.

[0002]

2. Description of the Related Art As a technique for compressing and transmitting signal data of a moving image having contrast, a conditional pixel supplement method (cond
An itional replenishment system has already been proposed (Harashima Hiroshi "Image Information Compression" pp.89-92, Ohmsha, 1
991). This conditional pixel replenishment method uses high correlation at the time of stillness in inter-frame prediction. By comparing the amount of prediction error between frames with an appropriate threshold value, pixels with greatly deviated prediction values are concentrated. The part that is doing is judged to be the area of pixels (significant pixels) worth transmitting,
The other part is determined to be a region of pixels (insignificant pixels) that only need to repeat the predicted value, that is, the value of the previous screen, and the image data is separated for each region. When transmitting this image data, the address related to the pixel is transmitted so that the significant / insignificant pixel can be distinguished, and the prediction error of the significant pixel is quantized or the prediction error in the field is transmitted separately. Encoding is performed by, for example,

FIG. 55 shows a moving picture compression apparatus to which the above-mentioned conditional pixel replenishment method is applied. This moving picture compression apparatus is inputted with an image input terminal 1 to which the grayscale moving picture signal S1 of the current frame is inputted. A motion detection / extraction circuit 10 for detecting / extracting the motion of the image signal S1 and outputting a motion extracted image signal S2, and an encoding circuit for encoding the motion-extracted image signal S2 and outputting an encoded signal S3. 20 and a decoding circuit 3 for decoding the encoded signal S3 to generate a decoded signal S4
2, the decoded signal S4 that has been decoded has only a motion area component, so that the reference image signal S6 and the decoded signal S4 are combined to generate a reproduced image S5, and a reproduced image S5 of a certain frame is accumulated. A frame memory 31 for outputting as a reference image for the next frame is provided, and the encoded signal S3 generated by the encoding circuit 22 is output to the outside through the output terminal 2. The motion detection / extraction circuit 10 includes an image cutout unit 11 for extracting a moving part from the input image signal S1 of the current frame.
And a difference circuit 12 that takes the difference between the image signal S1 of this current frame and the reference image S6 output from the frame memory 31 and outputs a difference result S7, and this difference circuit 12
A motion determination unit 13 that determines whether or not each part of the screen is a moving part based on the output of the above, and outputs a determination signal S8. As a determination method performed by the motion detection / extraction circuit 10, for example, a method of determining a moving part when the absolute value error is larger than a predetermined value, and a non-moving part when the absolute value error is small can be considered. . The encoding circuit 22 converts the motion extracted image signal S2 into an encoded signal S3 by, for example, a discrete cosine transform (DCT-discrete cosine transform-) encoding method or a vector quantization encoding method.

FIG. 56 shows a moving picture reproducing apparatus which reproduces a coded moving picture signal which is compressed by the moving picture compressing apparatus shown in FIG. 55 and transmitted. In FIG. 56,
Encoded video signal S3 input through the input terminal 3
Is converted into a motion area decoded signal S4 by the decoding circuit 41 and supplied to the synthesizing circuit 42. The synthesizing circuit 42 reads the reproduced image signal S6 of the immediately preceding frame stored in the frame memory 43 to obtain the motion area decoded signals S4 and 1
The reproduced image S obtained by synthesizing the reproduced image signal S6 before the frame is combined.
5 is output to the outside. The reproduced image signal S5 of the current frame is stored in the frame memory 43, and when the moving image signal of the next frame is reproduced, the reproduced image signal S of the previous frame is reproduced.
Used as 6.

Since the conventional moving picture compression / reproduction device having the above-mentioned structure and operation does not need to transmit the still portion of the screen because it adopts the conditional pixel replenishment system, a large amount of data can be stored. It becomes possible to perform compression. At this time, since the grayscale image normally uses pixel values of 256 gradations, a data length of 8 bits is required for each pixel. Therefore, if the image size is “352 × 24
If there are 4 "pixels, the frame memories 31 and 43 must hold 8 x 352 x 244 = 687104 (bits) of data only with the luminance signal, which requires a large-capacity memory. It was Further, the increase in the amount of data means that the motion detection / extraction circuit 10, the encoding circuit 20, the decoding circuits 32 and 41, the synthesizing circuits 33 and 4
There was also a problem that the amount of calculation of 2 also increased.

On the other hand, as a technique for significantly reducing the amount of data, in the technical field of still image transmission processing, when processing a grayscale image for transmission, hard copy, etc., halftone processing of a multi-tone image is performed. Several pseudo halftone display methods have been proposed to reduce the tones. In the binary image processing as a typical example of the halftone processing, a graphic portion is cut out from an image having a simple grayscale structure, a value 1 is assigned to this graphic portion, and a value 0 is assigned to the other portions.
After conversion into a value image, a procedure of analyzing the shape feature of the graphic portion is used. The systematic dither method and the minimum mean error method are used for halftoning the grayscale image.

In the systematic dither method, the screen is regarded as a set of "n × n" dot sub-matrices, and the threshold value is determined only by the coordinate information in the sub-matrix. The arrangement of the thresholds of the sub-matrix is a factor that greatly affects the image quality, and two types have been proposed: a dot dispersion type that emphasizes resolution and a dot concentrated type that emphasizes gradation. A two-step threshold value determination method is known as an arrangement of threshold values for obtaining the required number of gradations and resolution performance.

In the mean error minimum method, the error between the read density and the display density of the reference pixel is weighted by the distance from the target pixel and the averaged error is added to the target pixel, and a binary value is set by a certain threshold value. This corrected value is regarded as the density for the pixel after the processing is performed, and it is also called an error diffusion method. This method has a satisfactory level of gradation expression and resolution and is said to be strong in processing such as reduction, but its evaluation is different for a unique striped pattern.

However, such a halftone processing method has heretofore been practiced in the field of still image processing, and is used for displaying halftones in the field of moving image processing in which temporal elements are taken into consideration. It wasn't done.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to reduce the data amount of a moving image signal by halftoning a grayscale image, thereby making it possible to reduce the capacity of a frame memory and the amount of calculation at the time of compression / reproduction. It is an object of the present invention to provide a moving picture compression / reproduction system capable of significantly reducing noise.

[0011]

To achieve the above object, a moving image compression / reproduction system including a moving image compression apparatus according to the present invention outputs a reference image signal for displaying the first frame of an input image signal. Reference image generating means; motion detecting / extracting means for comparing the reference image signal with a second frame of the input image signal to generate a differential signal indicating a moving region of the input image signal; An image encoding means for encoding the signal to generate an encoded image signal having a resolution lower than that of the difference signal;

Further, the moving picture compression / reproduction system according to the present invention determines the error between the past image data and the present image data, extracts the moving region in the moving image, and outputs the motion extracted image data. Detection / extraction means, encoding means for encoding the motion-extracted image data and outputting the encoded image data, and sequentially updating the image data for each frame that is sequentially input to store the image data for each frame. A moving picture compression apparatus comprising: a frame storing means for outputting to the motion detecting / extracting means; and a compressed image processing loop including at least the motion detecting / extracting means and the frame storing means, before and after the compressed image processing loop. It is characterized in that it is provided with a halftone processing unit which is provided at any of the three places and which converts an input grayscale image into a low gradation image. Further, the moving picture reproducing apparatus in the moving picture compression reproducing system according to the present invention sequentially updates the decoding means for decoding the input encoded image data and the sequentially input image data for each frame, and A frame storage unit for storing image data for each frame; and a unit for generating reproduced image data by synthesizing decoded image data and image signals of past frames stored in the frame storage unit, A reconstructing means is provided in the replay image processing loop including the synthesizing means and the frame storing means, and provided in any one of three positions before and after the replay image processing loop, for reconstructing the input low gradation image into a grayscale image. It is characterized by

The halftone processing means is provided between the motion detecting / extracting means and the encoding means in the compressed image processing loop, and between the decoding means and the frame storing means. A synthesizing unit for synthesizing the image signal of the past frame and the decoded image signal stored in the frame storing unit is provided, and low gradation is provided between the frame storing unit and the motion detecting / extracting unit. Reconstruction means is provided for converting the image of FIG.

The halftone processing means is provided before the compressed image processing loop, and the compressed image processing loop detects and extracts the movement of the input image signal halftone-processed to low gradation, and the movement data Is encoded and output, is decoded by the decoding means, is combined with the image signal of one frame before stored in the frame storage means, and the frame image data stored in the frame storage means is updated, At the same time, the motion detecting / extracting means uses this frame image data to detect and extract the motion data of the input image of the next frame.

The moving image compression apparatus stores the input image data for one frame and outputs it to the motion detecting / extracting means, and forms the compressed image processing loop together with the motion detecting / extracting means. The halftone processing means comprises a frame storage means provided after the compressed image processing loop and between the halftone processing means and the encoding means.

The halftone processing means weights the error between the read density and the display density of the reference pixel by the distance from the pixel of interest and averages the error, and adds the error to the pixel of interest. Converting the grayscale image into low grayscale pixels using the average error minimization method, and the moving image compression apparatus further stores the low grayscale image as a past low grayscale image; And a subtractor for obtaining an error between the past low gradation image and the current image data and outputting the error to the halftone processing means.

The moving image compression apparatus further comprises a storage means for holding a plurality of low gradation vectors consisting of a plurality of low gradation data, and the halftone processing means outputs an output value obtained by halftoning an input image. The output value is determined in units of a plurality of pixels, and the low-gradation vector having a smaller error from the vector of the input image is determined as an output value.

The moving picture compression apparatus further comprises a storage means for holding a plurality of low gradation vectors consisting of a plurality of low gradation data, and the halftone processing means outputs an output value obtained by halftoning an input image. The output value is determined by taking into consideration the error between the grayscale image and the output image in a predetermined reference range in addition to the error between the low gradation vector and the vector of the input image among the plurality of pixels. There is.

The moving image reproducing apparatus is provided at the rear side of the reproduced image processing loop for processing the output of the decoding means for decoding the input coded image signal, and the code subjected to halftone processing. Reconstructing means for converting the reproduction signal after decoding and synthesizing the digitized image signal from the low gradation signal to the grayscale signal is included.

The moving image reproducing apparatus is provided between the reconstructing means and the reproduced image output terminal, and the grayscale image output from the reconstructing means and the synthesizing circuit are output by a switching signal from the outside. It includes a selection means for selecting either the low gradation image.

The moving image reproducing apparatus is provided between the output side of the decoding means and the input side of the reproduced image processing loop including the synthesizing means and the frame storing means, and is decoded by the decoding means. The reproduced low-gradation image signal is converted into a grayscale image signal, and the reproduction image processing loop includes a reconstructing means for synthesizing the grayscale image signal with a grayscale image signal of a past frame and outputting the synthesized grayscale image signal.

The moving picture compression / reproduction device according to the present invention is such that, on the compression device side, a halftone processing means for converting a grayscale image into a low gradation image at any of the three positions in the compressed image processing loop, the front and the rear. Since the image data stored in the frame storage means is halftone-processed and the data amount is significantly reduced, it is not necessary to prepare a frame memory having such a large capacity. In addition, the amount of data calculation in the compression process is significantly reduced, which contributes to speeding up the calculation process.

Also, in the moving picture compression / reproduction device according to the present invention, the reproduction device also has a reconstructing means for converting a low gradation image into a grayscale image in any one of the preceding stage and the subsequent stage of the reproduction processing loop. Is provided, the low-gradation image is reconstructed into a gray-scale image and then a moving image is reproduced after data transmission is performed using the low-gradation encoded image data that has been subjected to halftone processing.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of a moving image compression / reproduction system and method and a moving image wireless signal transmitting / receiving system according to the present invention will be described in detail below with reference to the accompanying drawings. In the following description, a binarization process is used as a typical example of the halftone process, and a binary image is used as a typical example of the low gradation image.

Before describing specific embodiments of the present invention, the basic concept of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a moving image compression apparatus which constitutes a moving image compression / reproduction system according to the present invention. In the figure, a moving image compression apparatus includes an input terminal 1 to which a grayscale moving image is input, an output terminal 2 that outputs a binarized image generated by halftoning the grayscale image, both terminals 1 and Motion detection / extraction means 10 provided between the two
An image coding unit 20 provided at a stage subsequent to the motion detecting / extracting unit 10 for halftoning a grayscale image and outputting it as a coded signal, and a motion detecting / extracting unit 10 and an encoding unit from the input terminal 1. A reference image generating means 30 for generating a reference image based on a detection signal supplied from any part of the main signal processing loop reaching the output terminal 2 via 20 and supplying the reference image to the motion detecting / extracting means 10. I have it. In the present invention, the configuration of the specific embodiment is different due to the difference in the supply source of the signal supplied to the reference image generating means 30.

The motion detecting / extracting means 10 detects the information of the moving area included in the grayscale moving image supplied via the input terminal 1 and cuts out the image, and the grayscale image. Of the reference image generated based on the frame before the predetermined frame from the input image information of the input frame, the subtracter 12 for obtaining the difference component, and the motion component based on the difference output of the subtracter 12 And a motion determination unit 13 that detects This structure is similar to that of the conventional compression device shown in FIG.

The image coding means 20 is provided with a halftone processing means 21 for inputting a grayscale image, performing image processing such as binarization and outputting a coded binary image. The reference image generation means 30 is provided between the motion detection / extraction means 10 and the image processing means 20 before the motion detection / extraction means 10 constituting the main signal processing loop (a signal path indicated by a chain double-dashed line in the figure). The moving image signal after the predetermined processing is input to any one of three positions (the signal path of the wavy line in the figure) and the subsequent stage of the image processing means 20 (the signal path of the one-dot chain line in the figure) to input 1 Storage means 31 for storing information for each frame
It has.

With the above configuration, the reference image generating means 30
Performs data processing and transmission of only the motion information for each frame based on the correlation of motion between frames of the moving image, and the image coding means 20 inputs the light and shade inputted using the minimum data of only the motion information in the moving image. Since the image is binarized and output, the halftone processing technique used in the still image processing field can be applied to the moving image processing field while suppressing the data transmission amount.

The moving picture compression apparatus according to the first to fifth embodiments of the present invention will be sequentially described below with reference to FIGS. 2 to 6. In each figure, FIG.
Those denoted by the same reference numerals as those in FIG. 3 indicate the same or corresponding components as those of the conventional moving image compression apparatus. Further, among the signal paths in each of these figures, the path indicated by the solid line is the signal path of the grayscale image, and the path indicated by the alternate long and short dash line is the signal path of the binary image as the low gradation image.

FIG. 2 shows a specific structure of the moving picture compression apparatus of the moving picture compression / reproduction system according to the first embodiment of the present invention. In the configuration shown in FIG. 2, the image encoding means 20 includes a halftone processing circuit 21 and an encoding circuit 2.
2, and the reference image generation means 30 synthesizes the frame memory 31 as a storage means, the output of the motion detection / extraction means 10 and the data of one frame before stored in the frame memory 31. And 33.

The moving picture compression apparatus according to the first embodiment cuts out the moving picture signal S1 input as a grayscale image for each frame by the motion information of the previous frame and supplies it to the image coding means 20. The image encoding means 20 performs halftone processing on the grayscale image and binarizes the image signal S13.
Output as As a result, the image data to be processed can be significantly compressed even in the moving image signal.

Further, the moving picture compression apparatus according to the first embodiment not only binarizes and compresses the moving picture signal, but also catches the motion component of the input moving picture as a correlation for each frame and makes a motion part. Since the motion detecting / extracting means 10 and the reference image generating means 30 are also provided in order to obtain only the information, it is possible to significantly compress the information from the viewpoint of processing the moving image signal.

FIG. 3 is a block diagram showing a moving picture compression apparatus according to the second embodiment of the present invention. The difference from the moving picture compression apparatus according to the first embodiment is the reference image generation. The input of the means 30 is the output of the image coding means 20, and the reference image generation means 30 is provided with the decoding circuit 32. Therefore, the reference image used for detecting the movement of the grayscale moving image signal of the currently input frame is subjected to the same halftone processing as the binarized image output to the reproducing side, and the encoding processing is performed. Is the image signal. This binary image signal is decoded by the decoding means 32 and supplied to the synthesizing circuit 33,
The subsequent signal processing operation is the same as that of the moving picture compression apparatus according to the first embodiment shown in FIG.

Next, a moving picture compression apparatus according to a third embodiment of the present invention will be described with reference to the block diagram of FIG. In the figure, the same reference numerals as those in FIGS. 1 to 3 and 55 are the same as or correspond to the respective constituent elements of the compressor according to the conventional example and the first and second embodiments. 4, reference numeral 1 is a moving image input terminal, reference numeral 10 is a motion detecting / extracting means including an image cutout unit 11, a difference circuit 12, and a motion determining unit 13, and FIG.
Like the moving picture compression apparatus of the related art No. 5, the encoding circuit 2
2, a decoding circuit 32, a synthesis circuit 33, and a frame memory 31 are also provided.

The characteristic structure of the moving picture compression apparatus according to the third embodiment is composed of the motion detecting / extracting means 10, an encoding circuit 22, a decoding circuit 32, a synthesizing circuit 33, and a frame memory 31. A halftone processing circuit 21 for converting the input grayscale moving image signal into a binarized image is provided in the compressed image processing loop 3, and the halftone is provided in the feedback processing loop 4 including the reference image processing means 30. That is, a reconstructing circuit 34 is provided for converting the image data, which has been converted into a binary image by the processing circuit 21 and subjected to the signal processing, back into a grayscale image signal again. The reconstructing circuit 34 performs inverse halftone processing on the halftone processing, so to speak. In the compressed image processing loop 3, the specific locations where both circuits 21 and 34 are provided are halftone processing. The circuit 21 is between the motion detecting / extracting means 10 and the encoding circuit 22,
A reconstructing circuit 34 is provided between the frame memory 31 and the motion detecting / extracting means 10.

Therefore, the compressed image data S13 output from the output terminal 2 is also a binarized data signal. The halftone processing circuit 21 receives the motion extraction image signal S2 output from the motion detection / extraction circuit 2 and converts the signal S2 from a grayscale image signal into a binary image signal. As the method of this conversion, similar to the still image described above, there are the systematic dither method and the minimum mean error method (see "Image Analysis Handbook" Mikio Takagi, Yohisa Shimoda, The University of Tokyo Press, 1991), etc., Based on the grayscale image, the gradation of the pixel value is reduced to binary by these methods.

The motion extracted image signal S12 which has been halftone processed by the halftone processing circuit 21 is
It is supplied to the encoding circuit 22, where it is encoded and output to the moving image reproducing apparatus via the output terminal 2 and also used for processing the image data input next by the compressed image processing loop 3. To be done. That is, it is decoded by the decoding circuit 32 to become the binarized decoded signal S14, and the synthesizing circuit 3
In 3, the image is combined with the binarized image signal S16 of one frame before stored in the frame memory 31. The frame memory 31 stores the synthesized binary image signal S of the current frame.
15 is updated to the image signal of a new frame and stored.
The binarized image signal stored in the frame memory 31 is supplied to the reconstruction circuit 34, where the binarized image signal is converted into a grayscale image signal and the motion detection / extraction means 10 is executed.
Output to

The reconstruction circuit 34 uses the document "Dither image edge detection and smoothing processing" (Kenichi Takahashi, Masamitsu Ota, IEICE Transactions 1985/6, Vol.J68-D No.6, pp.1345).
-1355), the binarized image is converted into a grayscale image and output as the reference image signal S6 to the motion detecting / extracting means 10. In the motion detecting / extracting means 10, the difference circuit 12 inputs the image signal S1.
And the reference image signal S6, the difference signal S7 is detected.
Is output to the motion determination unit 13. The motion determination unit 13 detects the motion component by comparing the image data of the current frame with the image data of the previous frame, and outputs the detection signal S8 to the image cutout unit 11. The image cutout unit 11 extracts the motion by cutting out the image signal S1 based on the detection signal S8, and the image signal with the motion thus extracted is supplied to the halftone processing circuit 21.

According to this moving image compression apparatus, since the input grayscale moving image is binarized by the halftone processing circuit 21, the data capacity stored in the frame memory 31 is 1/100 of the conventional one. It becomes possible to compress to 8. The reason is that the number of bits per pixel of the image held in the frame memory 31 can be reduced from the conventional 8 bits to 1 bit. Also, for the same reason, the encoding circuit 22, the decoding circuit 32, and the synthesizing circuit 33.
The amount of data to be processed in 1 can be reduced to 1/8, and the amount of calculation to be processed in the image compression processing loop 5 can also be reduced. Further, in the third embodiment, motion detection is performed by correlating moving images between frames.
Since extraction is also performed, it suffices to perform halftone processing on one reference frame without performing halftone processing on all claims of the moving image frame, and on subsequent frames only halftone processing for motion components. The transmission amount can be reduced.

Next, referring to FIG. 5, the fourth embodiment of the present invention will be described.
A moving image compression apparatus according to the embodiment will be described.
The moving picture compression apparatus according to the fourth embodiment has a configuration of the image coding means 20 in the moving picture compression apparatus according to the second embodiment shown in FIG. 3 as shown in FIG. The modified image coding means 20A is provided. The image encoding means 20A directly inputs the input signal S1 which is a grayscale moving image signal through the input terminal 1 and then performs halftone processing to supply the binarized moving image signal to the motion detecting / extracting means 10. A tone processing circuit 21 and an encoding circuit 22 for encoding the binarized moving image signal cut out for each frame by the motion detecting / extracting means 10 are provided. Therefore, in the compressing device according to the fourth embodiment, the halftone processing circuit 21 of the image coding means 20A.
Is provided immediately after the input terminal 1, so that
Or unlike the compression apparatus according to the third embodiment, the image signals processed by all the constituent elements of the motion detecting / extracting means 10 and the reference image generating means 30 are binary moving images.

Next, referring to FIG. 6, the fifth embodiment of the present invention will be described.
A moving image compression apparatus according to the embodiment will be described.
The moving picture compression apparatus according to the fifth embodiment has a terminal 1
A reference image generation unit 30 that stores the image of the frame immediately preceding the grayscale moving image signal S1 that is input via and outputs it as a reference image signal S6, and the grayscale of the current frame based on the reference image signal S6. Motion detection that cuts out an image from the moving image signal S1 and outputs a motion extraction grayscale image signal S2
An extraction means 10 and an image processing means 20 for halftoning the motion-extracted grayscale image signal S2 to binarize it and then encoding it to output a binarized image S13 are provided.

The reference image generating means 30 is composed of a frame memory 31 for storing a signal of the input grayscale image signal S1 one frame before. Further, the motion detecting / extracting means 10 inputs a grayscale image signal of one frame before stored in the frame memory 31 as a reference image signal S6 and takes a difference from the grayscale image signal S1 of the current frame. 12, a motion determination unit 13 that determines the correlation of motion between frames based on the difference signal S7, and an image is cut out from the current frame based on the output of the motion determination unit 13 and a motion extraction grayscale image signal S2 is output. The image cutout unit 11 is provided.

Further, the image processing means 20 receives the motion extraction grayscale image signal S2 output from the motion detecting / extracting means 10 and performs halftone processing to output it as a motion extraction grayscale image binarization signal S12. Binarization circuit 21
And a coding circuit 22 which receives the motion extraction grayscale image binarized signal S12, encodes it, and outputs it as a binarized coded image signal S13, and this binarized coding The image signal S13 is supplied to the image reproducing device side via the output terminal 2.

In the moving picture compression apparatus according to the fifth embodiment, a motion extracting loop 6 composed of the reference picture generating means 30 is formed on the grayscale image side, and two loops are provided on the latter side of the loop 6.
Since the image processing means including the binarization circuit 21 is provided, the frame memory 31 must have the same storage capacity as the conventional one, but the decoding circuit and the synthesis circuit on the compression side. And various components such as a reconfigurable circuit can be omitted. Therefore,
There is an effect peculiar to the fifth embodiment that the amount of calculation on the compression side can be reduced and further simplification of the device can be achieved.

Next, a moving image reproducing apparatus according to sixth to eighth embodiments of the present invention will be described with reference to FIGS. 7 to 9. First, a moving image reproducing apparatus according to a sixth embodiment of the present invention will be described with reference to FIG. The reproducing apparatus according to the sixth embodiment corresponds to the moving picture compression apparatus according to the second and third embodiments, and includes a decoding circuit 41, a synthesizing circuit 42, and a frame memory 43.
Corresponds to the configuration of the conventional reproducing apparatus shown in FIG. 56 except that a binarized image signal is processed.

In FIG. 7, a reconstructing circuit 44 for inversely converting a binarized image signal into a grayscale image signal is provided after the reproduction image processing loop 40 formed by the frame memory 43 and the synthesizing circuit 42. . In the above configuration, the binary coded compressed image signal S13 is supplied via the input terminal 3, and this signal S13 is decoded by the decoding circuit 41 and supplied to the synthesizing circuit 42 as the decoded binary image signal S14. It The synthesizing circuit 42 synthesizes the binarized frame image signal S16 of one frame before stored in the frame memory 43 and the decoded binarized image signal S14 and outputs the binarized image signal S15. This binary image signal S
15 is supplied to the reconstruction circuit 44 to be inversely converted from the binarized image signal to the grayscale image signal S5, and is output to the outside as a reproduced image signal via the output terminal 4.

In the moving image reproducing apparatus according to the sixth embodiment, the amount of image data stored in the frame memory 43 in the reproduced image processing loop 40 is 1/8 bit, which is the maximum in image information processing. There is a peculiar effect that it is possible to achieve the speeding up of the processing and the reduction of the device cost by suppressing the increase in the capacity of the memory which is a difficult problem.

Next, referring to FIG. 8, the seventh aspect of the present invention will be described.
A moving image reproducing apparatus according to the embodiment will be described. The device according to the seventh embodiment shown in FIG. 8 is the same as the device according to the sixth embodiment shown in FIG. Have a configuration. In the seventh embodiment, when a reproduced image signal is displayed on a binary display or is output as a binary value by a printer or the like, a binary image is output by an external switching signal supplied from a terminal 7. Signal S15
And the grayscale image signal S5 can be switched and output. That is, the reconstruction circuit 44 is provided in the subsequent stage of the reproduction image processing loop 40A,
The binarized image signal S15 can be converted into the grayscale image signal S5 and output. The configuration up to this point is the same as that of the reproducing apparatus according to the sixth embodiment shown in FIG. A selection circuit 45 is provided at the subsequent stage of the reconfiguration circuit 44. The selection switching signal S18 is supplied from the external input terminal 7 to the selection circuit 45.
The binarized image signal S15 is supplied.

Therefore, as described above, when it is necessary to output the binarized image signal S15 as it is,
The external switching signal S18 supplied from the external input terminal 5 switches and outputs either the signal S5 or S15 as the reproduced image signal to be output via the output terminal 4.

Next, a moving image reproducing apparatus according to the eighth embodiment of the present invention will be described with reference to FIG.
The reproducing apparatus according to the eighth embodiment corresponds to the compressing apparatus according to the fifth embodiment shown in FIG. 6, and reproduced image processing formed by the synthesizing circuit 42 and the frame memory 43. The reconfiguration circuit 44 is provided in the preceding stage of the loop 40B.
Is provided. The operation of the reproducing apparatus according to the eighth embodiment will be described. The binarized compressed image signal S13 supplied via the input terminal 3 is decoded in the decoding circuit and supplied to the reconstruction circuit 44 as the binarized decoded image signal S14. The reconstructing circuit 44 converts the binarized signal S14 into a grayscale image signal S4 and supplies it to the synthesizing circuit 42. The synthesizing circuit 42 receives the image signal of one frame before as the reference image signal S6 from the frame memory 53, synthesizes the reproduced image signal S5, and outputs the synthesized image signal S5 to the outside through the output terminal 4.

In the eighth embodiment, it is not possible to obtain a peculiar effect, but in the point that signal processing can be performed using a binarized image signal on the compression device side, a fifth effect is obtained. The combination of the compression device according to the embodiment and the reproduction device according to the eighth embodiment contributes to the effectiveness of the present invention.

The above-described first to eighth embodiments are applicable to both wired and wireless transmission methods, and the configuration between the input and output terminals on the transmission side and the input on the reception side. 10 and FIG. 11, respectively, the ninth and tenth embodiments in which the moving picture compression / reproduction device according to the present invention is applied to the wireless transmission system are shown in FIGS. There is.

FIG. 10 is a block diagram showing a moving picture wireless signal transmission / reception system according to a ninth embodiment of the present invention. The compression apparatus according to the ninth embodiment is a specific example applied to a moving image wireless signal transmission / reception system, in which a low tone image subjected to halftone processing is placed on a carrier signal of a wireless frequency and wirelessly transmitted. is there.

The moving picture compression / transmission device 50 shown in FIG.
Is a camera 51 that captures a subject and captures it as a grayscale image.
And a halftone processing circuit 52 that halftone-processes the grayscale image signal S1 supplied from the camera 51 and outputs a low gradation image signal S12; A modulation circuit 53 that outputs the image signal S20 and an antenna 54 that outputs the moving image signal S20 are provided. The modulation circuit 53 generates a moving image signal S20 having a predetermined transmission frequency, and the antenna 54 radiates a radio wave S21 into the air.

FIG. 11 is a block diagram showing a moving picture reproducing apparatus according to the tenth embodiment of the present invention. This first
The reproducing device according to the 0th embodiment receives and reproduces the radio wave S21 transmitted through the compressing device according to the 9th embodiment, for example, and reverses the demodulated low gradation image signal. Halftone processing is performed to reconstruct a grayscale image.

The moving picture receiving / reproducing apparatus 55 shown in FIG.
Is an antenna 56 that receives the radio wave S21 and the radio wave S21 received by the antenna 56.
And a reconstructing circuit 5 for performing a reverse halftone process on the low gradation image signal S22 to reconstruct it as a grayscale image signal S5.
8 and a display 59 for displaying an image on the screen based on the grayscale image signal S5.

FIG. 12 is a block diagram showing a moving picture compression / reproduction device according to an eleventh embodiment in which the present invention is incorporated and applied to a portable videophone.

In FIG. 12, the portable videophone 60 is
It is divided into a compression side and a reproduction side via a transmission / reception circuit 65 having an antenna 54 (or 56). The compression transmission side
A camera 51, a microphone 61, an image encoder 62 that encodes the image signal S1 captured by the camera 51 and outputs an image code S24, and an audio signal S25 that is acoustically-electrically converted by the microphone 61. A voice encoder 63 that outputs a voice code S26, and a multiplexer 64 that multiplexes the image code and the voice code output from each encoder to generate a multiplexed signal S27 are provided. The transmission / reception circuit 65 emits the transmission signal S20 generated by converting the multiplexed signal S27 into a predetermined frequency as a radio wave through the antenna 54 (56).

The transmission / reception circuit 65 receives the radio wave from another portable videophone via the antenna 56 (54) and supplies it to the separator 66 as the multiplexed signal S28. The receiving / reproducing side receives a multiplexed signal S28 and separates it into an image code S29 and an audio code S30, and an image decoder 67 which decodes the separated image code S29 to generate an image signal S5. , A voice decoder 68 for generating a voice signal S31 by combining the separated voice codes S30, and an image signal S
Display 59 for reproducing and displaying 5, and audio signal S
And a speaker 69 for converting 31 into voice and outputting the voice.

In the above structure, the camera 51 is used for transmission.
The image signal S1 captured by S1 and the audio signal S25 captured by the microphone 61 are encoded into an image code S24 and an audio code S26 by the image encoder 62 and the audio encoder 63, respectively. The image encoder 62 performs image compression processing by detecting and extracting motion in a moving image simultaneously with image encoding. By providing the halftone processing circuit or the binarization circuit according to the above-described embodiment in the preceding stage or the loop of this compressed image processing loop, the image data to be transmitted can be greatly reduced. Similarly, the capacity of the frame memory in the image compression loop can be reduced.

Also on the receiving side, the image decoder 6
At the same time as the decoding of the image code, the reference numeral 7 expands the compressed image data by using the reproduction image processing loop. Therefore, by providing a reconstructing circuit for performing the inverse halftone process in the preceding stage or the latter stage of the reproduced image processing loop including the frame memory and the synthesizing circuit, it is possible to process the image data to be reproduced with a small amount of data and then reconstruct it. it can. As described above, bidirectional wireless communication using low gradation image data and audio data becomes possible.

Finally, a twelfth aspect of the appearance of the bidirectional compression reproducing apparatus according to the eleventh embodiment shown in FIG.
A portable videophone device according to the embodiment will be described. As shown in FIG. 13, a portable videophone device 70 according to the twelfth embodiment has a camera 71 provided on the surface of the main body.
, Display 72, microphone 73, speaker 74
And an operation key 75, and a transmitting / receiving antenna 76 is arranged on the upper part of the main body. The other electronic circuit has, for example, a structure such as the bidirectional compression reproducing apparatus according to the eleventh embodiment shown in FIG. 12, and is housed in the casing of the main body.

The ninth to twelfth embodiments described above all show configuration examples when the moving picture compression / reproduction system according to the present invention is applied to a two-way wireless information communication terminal. Although it can be applied to various communication terminals as described above, it includes not only the illustrated embodiment but also reconstruction processing as image halftone processing and inverse halftone processing, which is the gist of the present invention. Any modification or change is possible. For example, when the moving picture compression / reproduction system according to the present invention is applied to a reception-only communication terminal, basically at least three configurations of a receiving unit such as an antenna, a decoding unit including a reconstructing unit, and a display output unit such as a display are provided. It is feasible if it has elements.

The moving picture compression / reproduction system according to the above-described first to twelfth embodiments can be summarized as shown in FIG. Here, halftoning means that a grayscale image having a real value of 0 to 10 as a luminance value is 0 or 2 of 2
Refers to using only values. In FIG. 14, a grayscale image of one frame before is stored in the memory 31 in advance. The grayscale image S1 of the current frame is input to the image cutout unit 11 and the subtractor 12. The memory 31 supplies the grayscale image S6 of one frame before to the subtractor 12. The subtractor 12 is
The difference S7 between the grayscale image S1 of the current frame and the grayscale image S6 one frame before is sent to the motion determination unit 13 for each frame portion. In the motion determination unit 13, a portion where the difference S7 is larger than a predetermined value is set as a moving region, and other portions are set as still regions, and the movement information S8 is sent to the image cutout unit 11.

In such a structure, for example, as shown in FIG. 15, a frame is divided into a plurality of blocks, and a static block or a moving block is determined for each block. In FIG. 14, the image cutout unit 11 outputs only the image S2 of the motion area from the grayscale image S1 of the current frame according to the motion information S8, and outputs it to the binarization circuit 21 and the memory 31.
Send to In the memory 31, the image S2 of the moving area is overwritten to prepare for the movement detection of the next frame. Binarization circuit 21
Then, the grayscale image S1 is halftoned and the binary image S
12 is sent to the encoding circuit 22. The encoding circuit 22 encodes the binary image S12 by a method such as entropy encoding or vector quantization, and outputs the code S13 to the outside.

FIG. 16 shows a reproducing apparatus corresponding to this.
A reproduced binary image of one frame before is stored in the memory 43 in advance. Reference numeral S13 is a decoding circuit 41 for the binary image S.
14 and sent to the memory 43. In the memory 43, the moving area is overwritten with the binary image S14 and output as the reproduced binary image S5 of the current frame.

By the way, there are several halftoning methods, and one of them is the average error minimum method. In this method, for example, "Image Analysis Handbook"
(Supervised by Mikio Takagi, Haruhisa Shimoda, University of Tokyo Press, 1991.
As described on page 495 of "Year", when determining the value of each image in order from the upper left of the grayscale image, the image whose image value shown in FIG. 17 has already been determined is used as a reference image. The value of the processed image is determined so as to reduce the average error in the range of “processed image + reference image” by obtaining the error of the brightness value due to binarization not only in the processed image but also in the reference image.

With the minimum average error method, a high-quality binary image in which the resolution and gradation of the original image are relatively maintained can be obtained. Therefore, there is a demand to use this in the binarization circuit 21 of FIG. In that case, the image in the still region is removed by the clipping circuit 11 and cannot be used as a reference pixel by the binarization circuit 21. For example, as shown in FIG. 21, when the processed image is at the upper end of the motion area, the error for the upper two columns cannot be referred to and binarization is performed. When the binary image of the moving area created in this way is combined with the binary image of the still area one frame before, a boundary is easily perceived between the still area and the moving area, and the image quality of the reproduced image deteriorates. Will end up.

Further, as shown in FIG. 19, the cutout circuit 2
It is also possible to dispose the binarization circuit 21 before 3, so that the still region can be referred to when the motion region is binarized. However, in this case as well, the binary image in the still area to be referred to is not transmitted in the end, and the error there is different from the error in the same part in the reproduced image. Therefore, distortion still occurs at the boundary between the moving area and the still area of the reproduced image.

As described above, the apparatus according to the first to twelfth embodiments described above has a problem that the boundary of the non-transmitted portion may be distorted and the image quality may be deteriorated.

In order to solve this, in the embodiment described below, the error between the past image data and the current image data is determined, the moving area in the moving image is extracted, and the motion extracted image data is extracted. Motion detection / extraction means for outputting, halftone processing means by the average error minimum method for converting the motion extracted image data into a low gradation image, and encoding the low gradation image and outputting encoded image data. Encoding means, a frame storage means for sequentially updating the input image data for each frame to store the image data for each frame, and outputting the image data to the motion detecting / extracting means, and the low gradation image Is stored as a past low gradation image, and a subtractor for obtaining an error between the past low gradation image and the present image data and outputting the error to the halftone processing means.

In the case of such a configuration, 1
The low-gradation image before the frame is held in advance, the error between the low-gradation image and the current gray-scale image is obtained, and the error is used as the error in the reference pixel for binarizing the motion area of the current frame. Is possible. As a result, it is possible to reproduce a code capable of reproducing an image having no distortion at the boundary between the non-transmitted portion and the transmitted portion.

The moving picture compression / reproduction system according to the thirteenth embodiment of the present invention will be described below with reference to the drawings.

FIG. 20 is a block diagram showing the thirteenth embodiment of the present invention. 20, the configurations and operations of the memory 31, the cutout unit 11, the subtractor 12, and the motion determination unit 13 are the same as those in FIG. 55 described in the section of the related art. A reproduced binary image of one frame before is stored in the memory 24 in advance. The grayscale image S1 of the current frame is also input to the subtractor 25, and the reproduced binary image S40 of the previous frame read from the memory 24 is also input to the subtractor 25.
In the subtractor 25, the grayscale images S1 and 1 of the current frame of each pixel
The difference between the reproduced binary images before the frame, that is, the error S41 is calculated and sent to the binarization circuit 21.

The image S2 of the moving area is input to the binarizing circuit 21, and as shown in FIG. 21, binarization is performed in order from the upper left pixel of the moving area. Here, the binarization is the error S
41, the average error minimum method is used. In the average error minimum method, as shown in FIG. 20, "error = gray value-binary weighted average value S" of predetermined reference pixels around the processing pixel to be binarized is first obtained. When the brightness value f of the processed pixel is larger than "1 / 2-S", "binarized output of the pixel = g = 1", and when it is smaller, "g = 0" is determined. This is also equivalent to selecting g = 0 or 1 in which the distortion amount Z = | f + S−g | becomes small.

The processed pixel is naturally in the motion area, but the reference pixel is in the motion area as shown in FIG.
In some cases, it may be in a still area as shown in FIG.
Therefore, when the reference pixel is in the motion area, the error in the reference pixel is equal to the gray value-binary of the current frame, and when the reference pixel is in the still area, the error S4 is used, that is, the error in the reference pixel = Gray value-1 binary value of one frame before. By doing so, even if only the moving area is changed to a new value and displayed as the current frame in the binary image of the previous frame at the time of reproduction, the boundary between the moving area and the still area is not distorted.

Returning to FIG. 20, the binary image S12 is sent from the binarizing circuit 21 to the memory 24 and the encoding circuit 22.
In the memory 24, the moving area is overwritten with the binary image S40,
Prepare for the next frame. The encoding circuit 22 encodes the binary image by entropy encoding, vector quantization, etc., and outputs the code S13 to the outside. Symbol S1
3 is reproduced by the reproducing apparatus shown in FIG.

Next, FIG. 24 is a block diagram of a moving picture compression / reproduction device according to the fourteenth embodiment which incorporates motion compensation.
Shown in The difference from FIG. 20 is that the memory 31 and the subtractor 12 are
This is the point where the motion compensator 35 is inserted between and. The grayscale image S1 of the current frame is also input to the motion compensator 35, and the grayscale image S1 of the previous frame is shifted by matching vertically and horizontally to detect the motion vector of the entire frame, and the shifted grayscale image of the previous frame is detected. Subtractor 1 for S42
Send to 2. The other configurations are the same as those in FIG. 20, and thus redundant description will be omitted.

Next, FIG. 25 shows a moving picture compression / reproduction system according to the fifteenth embodiment in which the binarization method is switched by a block. The image S2 of the moving area is input to the block type determination circuit 26 for each block. For example, when the block variance is smaller than a predetermined value, the block type determination circuit 26 determines that the block is a flat block, obtains the average value S43 of the brightness within the block, and outputs the average value S43. Then, without using each brightness value in each block, a binary image is created by an appropriate method only from the average value, and is overwritten in the memory 24 as a binary image S42 of a flat block. Only the image S44 of the non-flat block is sent to the binarization circuit 21. In a halftone image, the average brightness is perceived at the ratio of 0 and 1 in the block, so when the average value is known, 0 and 1 may be randomly arranged, for example, at a ratio that matches the average value. In a flat block, it is not necessary to represent something by the arrangement of 0 and 1.

Next, FIG. 26 shows a moving picture compression / reproduction device according to the sixteenth embodiment, which uses a vector quantizer as the encoding circuit 22. The binarization circuit 21 uses the error signal S4.
The binary image signal S45 is generated from the motion area image signal S2 while referring to 1, and is output to the codebook generation circuit 27. In the codebook generation circuit 27, the binary image signal S4
5 are grouped for each predetermined number of pixels and treated as a vector. For example, when the pixel value of the binary image signal S46 is 001101100100100011010110 0110100000111101100100000 and the number of vector elements is set to 4, (0011) (0110) (0100) (1000) (1101) (0110) (0110) ) (1000) (0011) (1101) (1001) (0000). Then, a plurality of vectors having a high appearance frequency are selected, and indexes are made to correspond to them to form a codebook signal S46. In the above example, since 0011 2 0110 3 0100 1 1000 1000 2 1101 2 1001 1 0000 1 If the index is 2 bits, the codebook signal S46 is index 00 vector 0110 index 01 vector 0011 index 10 vector 1000 and index 11 vector 1101 are obtained. The codebook signal S46 is sent to the codebook memory 28, and at the same time, sent to the reproducing device.

The image S2 of the motion area and the error S41 are also sent to the vector quantizer 86. Vector quantizer 22a
Then, the motion area image signal S2 is also treated as a vector, and the index of the vector that gives the smallest vectorization distortion amount V thereto is output as the code S47 of the vector. Here, as the vectorized distortion amount V, the vector of the image signal S2 in the motion area is (f1, f2, f3, f
4), binary vector signal S read from the codebook
When 48 is (g1a, g2a, g3a, g4a), V = Z1 + Z2 + Z3 + Z4 = | f1 + M1-g1 | + | f2 + M2-g2 | + | f3 + M3-g3 | + | f4 + M4-g4 | M1 to M4 are weighted average values of the errors obtained from the error S41, M1 is calculated in the range of the reference pixel f1 shown in FIG. 27, and M2 is calculated in the range of the reference pixel 77 of f2. In f1 included in the reference pixel 78 of f2, since a binary pixel value has not yet been determined, f1-g1a is used as the error there. Similarly, M3 and M4 are obtained by shifting the range of reference pixels. This allows image compression while keeping both the binarization error and the vectorization error small.

A fixed codebook can be stored in the memory 28 in advance. In this case, the binarization circuit 21 and the codebook generation circuit 27 are unnecessary, and it is not necessary to send the codebook to the reproducing device.

The code S47 is input to the vector dequantizer 22b. Here, the binary vector signal S48 corresponding to the index is read from the memory 28, the binary image signal S49 is reproduced, and the motion area portion of the memory 24 is overwritten.

FIG. 28 shows a reproducing apparatus according to the seventeenth embodiment corresponding to the compressing apparatus shown in FIG. Codebook S
46 is stored in the memory 28, and the code S2 is input to the vector dequantizer 22b. Vector dequantizer 22b
The binary image S49 reproduced by is overwritten on the moving part of the memory 24 and becomes a reproduced binary image S40.

FIG. 29 shows an eighteenth embodiment in which the moving picture compression / reproduction system according to the present invention is used in a moving picture wireless communication system. In FIG. 29, an engineering workstation (hereinafter referred to as EWS-Engineering) that constitutes a system 80 in which a moving image compression system according to the present invention for halftoning a moving image into a binary image transmits the moving image via wireless communication. Work Station-) 81
It is attached to. The image around the EWS 81 is captured as a grayscale image S1 by the camera 82, and the resulting code S50 that has been binarized and encoded is sent to the wireless device 83.
In the wireless device 83, the signal 84 is modulated into a predetermined transmission band.
Uses the network 88 and signal 85
3, the code S51 is demodulated. The symbol S51 is reproduced by the image reproducing device in the personal computer 86 and displayed on the display 87 of the personal computer 86. Since the system 80 uses the code by the compression device of the present invention, a reproduced image with less distortion than the conventional one can be obtained.
Further, if a compression device is provided in the personal computer 86 and a reproducing device is provided in the EWS 81, image transmission from the personal computer 86 to the EWS 81 is also possible, which enables bidirectional moving image communication.

FIG. 30 is a block diagram showing the nineteenth embodiment of the present invention. In FIG. 30, the multi-gradation image signal S1 of the current frame input from the image input terminal 1 is sent to the image processing circuit 91. In the image processing circuit 91, the image signal S1 is subjected to halftone processing and encoding, and the encoded signal S13 is sent to the code amount monitoring circuit 92.

As the encoding method in the image processing circuit 91,
For example, (1) Out of the image signal S1, only a portion having a movement compared with the previous frame is cut out and output. (2) The halftoned image is vector-quantized and its index is output. (3) The flat part outputs only its average value. Etc. (The details of these are described in another embodiment.)
One or a combination of the two is used.

The code amount of the generated coded signal S13 varies greatly with time due to the fineness of the pattern of the image and the intensity of the movement, so that the coded signal S13 cannot be directly output to the communication path or the like. Therefore, in the code amount monitoring circuit 92, only the signal within the predetermined allowable code amount of the encoded signal S13 is passed, and it is output from the output terminal 2 as the transmission signal S55. Further, the code amount monitoring circuit 92 sends a control signal S56 for controlling the generated code amount to the image processing circuit 91 as needed. According to the control signal S55, the image processing circuit 91 uses, for example, (1): a threshold value for dividing a moving part / still part (2): the number of bits of the index (3): a flat part / non-flat part The coding parameters such as the threshold for dividing the part are switched to increase or decrease the generated code amount.

Although the code amount monitoring circuit 92 is connected to the output terminal 2, its configuration changes depending on the transmission conditions. FIG. 31 shows a configuration example of the twentieth embodiment in the case where the output terminal 2 is connected to the communication path in which the transmission code amount per unit time is determined. The encoded signal S13 is once held in the memory 93. Then, from the memory 93, the temporarily held signals are read out by a predetermined amount in the order of oldness, and the transmission signal S5
5 is output. The memory amount check circuit 94
Thus, the memory amount of the memory 93 is constantly checked, and when the memory amount increases, a control signal S56 for reducing the generated code amount is generated. Conversely, when the memory amount approaches zero, the control signal S5 for increasing the generated code amount
Generate 6.

Next, although the transmission amount per unit time may vary to some extent, if the allowable maximum value of the average transmission amount within a predetermined time is determined, it will be described as a 21st embodiment. It is configured as shown in 32. The encoded signal S13 is output as it is as the transmission signal S55 via the switch 96, but the counter 95 constantly counts the transmission code amount within the latest predetermined time, and the count value is likely to exceed the maximum value of the code amount. When it becomes, the switch 96 is cut off and the transmission of the transmission signal S55 is temporarily stopped. After that, when the count value becomes sufficiently small, the switch is connected again. Then, control is performed so that the amount of the coded signal S13 is reduced when the coded signal S13 is too much and the switch has to be frequently disconnected, and conversely, the code amount is increased when the transmission amount has a margin. The signal S56 is generated.

As described above, in the nineteenth to twenty-first embodiments, it is possible to generate the transmission signal S55 that matches the transmission condition regarding the code amount.

FIG. 33 shows the structure of a moving picture compression apparatus according to the 22nd embodiment for controlling the frame rate, that is, the number of transmission frames per unit time. In the case of a moving image, if the transmitting side transmits, for example, 30 frames per second, a smooth video can be reproduced on the receiving side.
It is necessary to reduce it to 0 frames / second or 5 frames / second.

A coded image signal S57 having a high frame rate of, for example, 30 frames / second is input from the input terminal 1A and sent to the switch A8. Further, the frame synchronizing signal S58 in which a pulse rises at the beginning of each frame is input from the input terminal 1B and sent to the counter 99. The counter 99 counts the number of pulses of the frame synchronization signal S58. For example, when it is desired to set 10 frames / second, the switch 98 is connected only when the count value is divisible by 3.
Otherwise, the switching signal S59 for disconnecting the switch 98 is sent to the switch 98.

The image signal S1 that has passed through the switch 98 is input to the image processing circuit 97, halftoned and encoded, and then output from the output terminal 2 as an encoded signal S13.

As described above, in the twenty-second embodiment, images can be transmitted at a predetermined frame rate. FIG. 34 is a diagram showing a twenty-third embodiment in which a function for switching the frame rate is added to the embodiment for controlling the generated code amount by switching the encoding parameters shown above. When the code amount monitoring circuit 92 determines that the generated code amount is too large and the allowable transmission amount cannot be suppressed only by switching the encoding parameter, it sends the switching signal S59 to the switch 98, disconnects the switch 98, and displays the image. Signal S
Suspend the input of 1. As a result, the amount of transmission can be suppressed below the permissible value even when an image with a large amount of motion is suddenly input, and the image processing circuit 97 unnecessarily halftones or encodes an image that cannot be transmitted. Disappears.

In the moving picture compression / reproduction system according to the above-mentioned first to twenty-third embodiments, the grayscale image is input as described above, halftone-converted, and then encoded. However, there is a problem in that an appropriate coding method cannot be used for each block, and as a result, the code amount cannot be reduced while maintaining the image quality.

In the twenty-fourth and subsequent embodiments described below, a means for converting a grayscale image input from the outside into a low gradation image and the low gradation image are encoded into a plurality of types of codes. Encoding means, selecting means for selecting one of these plural types of codes as an output code by a selection signal, means for determining the selection signal for each block using the grayscale image, and the output code Basically, communication coding means for converting the selection signal into a code string is provided to enable the most appropriate coding for each block. Hereinafter, these specific embodiments will be described in detail with reference to FIGS. 35 to 46.

FIG. 35 is a block diagram showing the structure of the image coding means applied to the moving picture compression apparatus according to the twenty-fourth embodiment. In FIG. 35, the image coding means 20
Is a binarization circuit 21 that performs halftone processing on a grayscale image, a block coding circuit 22 that encodes and outputs a binarized halftone signal in block units, and a block in an input grayscale image. A block class determination circuit 29 that determines a class and a selection unit 100 that selects a plurality of types of images based on the output of the block class determination circuit 29 are provided.

The selecting means 100 switches the binarized halftone image S61 by the selection signal S62 output from the block class determining circuit 29.
01, a density detection circuit 102 that detects the density from the halftone image and outputs it as the density code S63, and a copy encoding circuit 103 that outputs the copy code S64 extracted from the halftone image.

The operation based on the above configuration will be described. First, the halftone image S60 is displayed in the switching circuit 101.
Is input to The switching circuit 101 has three output terminals 1
There are 11, 112, and 113, and there is a halftone image S61.
Depending on the selection signal S62, the output terminals 111, 112,
It is output from any one of 113. When output from the output terminal 111, the halftone image is directly sent to the block coding circuit 22, when output from the output terminal 112, it is sent to the density detection circuit 102, and when output from the output terminal 113, it is copied. It is sent to the encoding circuit 103. And
A density code S63 is output from the density detection circuit 102,
Further, the copy encoding circuit 103 outputs a copy code S64.
Are sent to the block coding circuit 22.

Next, a moving picture compression apparatus according to the twenty-fifth embodiment having a configuration different from that of the twenty-fourth embodiment shown in FIG. 35 will be described with reference to FIG. In the block diagram of FIG. 36, the grayscale image S60 fetched from the input terminal is supplied to the binarization circuit 21 and the block class determination circuit 29. The binarization circuit 21
By converting the grayscale image S60 into a halftone image S61,
This is supplied to the switching circuit 101, the density detection circuit 102, and the copy coding circuit 103. The density detection circuit 102 counts the number of black pixels in each block, and the density code S63
Is supplied to the switching circuit 101.

Comparing the twenty-fourth embodiment of FIG. 35 with the twenty-fifth embodiment of FIG. 36, in the embodiment of FIG. 35, only one type of coding needs to be performed for each block. Therefore, there is an advantage that the total calculation amount can be reduced, but it takes some time because encoding is started after the block class is determined. On the other hand, in the embodiment of FIG. 36, since the block class determination and binarization / encoding can be performed simultaneously in parallel, there is an advantage that the code string S65 can be output in a short time. You have to find the sign. Therefore, the two embodiments may be used properly depending on what purpose the moving image signal is used for.

FIG. 37 shows a concrete configuration example of the copy coding circuit 103 used in the twenty-fourth and twenty-fifth embodiments. The memory 106 holds the locally decoded data of the transmitted blocks. The halftone image S61 to be encoded is input to the difference circuit 107, and the difference circuit 107 receives the address S from the copy source determination circuit 108.
The reference block S67 designated by 66 is also supplied from the memory 106. This reference block S66
As shown in FIG. 38, as shown in FIG. 38, some plural ones are selected from near the halftone image S61 to be encoded, and each reference block S66 and the halftone image S are selected.
The error S68 of 61 is sent from the difference circuit 107 to the copy source determination circuit 108, and the copy source determination circuit 108 outputs the position information of the reference block when the error S68 is the smallest as the copy code S64.

Returning to FIG. 36 again, the copy code S64 is sent to the switching circuit 101. The block class determination circuit 29 is described in, for example, the document "Classified vector quantizati.
onof images "(B.Ramamurthi and A.Gersho IEEE Trans
acions on communication, Vol. COM-34, No.1
1, NOV. 1986) using the method in Appendix A
The grayscale image S60 is represented by a flat block (shade), a simple edge block (edge), a composite edge block (mixed),
Classify as any of the mid-amplitude blocks (mid range). When the grayscale image S60 is a flat block or a medium amplitude block, the selection signal S6 for selecting the density S63 is selected.
2 is transmitted, and if the grayscale image S60 is a simple edge block, a selection signal S62 for selecting the copy code 50 is transmitted, and if it is a composite edge block, the halftone image S
It is determined that the selection signal S62 for selecting 61 is transmitted. The selection signal S62 is the block encoding circuit 22.
Is also supplied. Code S selected by the switching circuit 101
65 is also supplied to the block coding circuit 22, and the block coding circuit 101 selects the selection signal S62 and the code S65.
Are collectively output as a code string S69 from the output terminal.

The block coding circuit 101 may collect blocks of a fixed size, but the block size may be variable when it is desired to reduce the code amount even if the calculation amount is increased a little. That is, when the selection signal S62 and the code S65 are constant in the adjacent blocks, those blocks are integrated. In this way, the selection signal S62 and the code S6
It is enough to give one set to the block that integrated 5
The code amount is smaller than that of providing the selection signal S62 and the code S65 by making the blocks not to be integrated separately. Of course, the block size information has to be included in the code string S69, but the effect of reducing the above-mentioned code amount becomes greater than the increase. There are various conceivable conditions for integrating the blocks. For example, when the block size is 4 × 4 pixels, the blocks are first classified into the following five types by the selection signal S62 and the density S63.

1. By selecting the density, the density is 0 (white solid) 2. With the density selection, the density is 16 (black solid). Concentration selection allows the concentration to be 1 to 15 4. Copy code selection 5. Halftone image selection Then, when adjacent blocks have the same type, the blocks are integrated. The integrated result is as shown in FIG. 39, for example. The code string includes block size information, block type information (integrated block unit), density of blocks having a block type of 3 (4 × 4 block unit),
Copy code of a block whose block type is 4 (4 ×
4 block units), and halftone image data (4 × 4 block units) of a block whose block type is 5 is included. In this method, it is no longer necessary to transmit anything in a solid block or a solid black block in units of 4 × 4 blocks. Therefore, if the amount of solid white or the amount of solid black is large, the code amount can be significantly reduced.

FIG. 40 shows a schematic structure of a moving picture reproducing apparatus according to the twenty-sixth embodiment which reproduces a moving picture by receiving the code string S69 outputted from the compressing apparatus shown in FIG. In FIG. 40, the code string S69 is taken in from the input terminal 121 to the reproduction circuit 120, and the block decoding circuit 1
Sent to 22. In the block decoding circuit 122, the code string S69 is divided into a selection signal S70 and a code S71, both of which are input to the switching circuit 123. In the switching circuit 123, the destination of the code S71 is switched by the selection signal S70, and when the code S71 is the halftone image, it is directly sent to the output terminal 126 as the reproduced halftone image S72, and when the code S71 is the density, the density is outputted. It is sent to the reproduction circuit 124, and in the case of a copy code, it is sent to the copy decoding circuit 125.

The density reproducing circuit 124 has a method of randomly arranging black pixels of the number of densities in a block at random or arranging the black pixels of the number of densities in a predetermined arrangement order as shown in FIG. is there. These can be reproduced with a relatively small amount of calculation. A method of reproducing a grayscale image once by this density and binarizing the grayscale image is also considered. For example, if the block size is 4 × 4 pixels and the density value a (0 ≦ a ≦ 1
6), the block average brightness value b is estimated by b = 0.5 * a / 16 + 0.25, and the grayscale image S60 is estimated with this brightness value b as shown in FIG. Note that in FIG. 42, the pixels are arranged one-dimensionally for simplification of the description, but in the actual image, the number of pixels is two.
It is lined up in a dimension. This halftone image S60 is binarized to obtain a halftone image S75. Furthermore, the block average value of FIG. 42 is referred to in the document “Position study of AC component prediction method using average value” (Watanabe, Ozeki, Image Coding Symposium, 2-
2, 1989) and the like, and smooth connection as shown in FIG. 43, block-like distortion never appears in the reproduced image. Although this method has a large amount of calculation as compared with the method of randomly arranging black pixels or arranging them in a predetermined order, the image quality of a portion where the luminance of the reproduced image changes smoothly becomes natural.

Returning to FIG. 40, the copy decoding circuit 125 already holds the reproduced halftone image, and the data S74 of the portion designated by the copy code is used as the reproduced halftone image S75 of the block.

The halftone image S73 or S74 reproduced by the density reproducing circuit 124 or the copy decoding circuit 125 is sent to the output terminal 126 as a reproduced halftone image S75.

Next, the configuration of the moving picture compression apparatus according to the 27th embodiment will be described with reference to FIG. In the twenty-seventh embodiment, the image coding means 20 surrounded by a dotted line in FIG. 35 or 36 is used for compressing a moving image. In FIG. 44, the grayscale image S0 captured by the camera 51 is sent to the preprocessing circuit 131. The pre-processing circuit 131 is composed of a noise reduction circuit and the like described on page 189 of the document "Multidimensional signal processing of TV images" (Takahiko Fukibe, Nikkan Kogyo Shimbun, 1988), and removes noise. As a result, a grayscale image S1 in which the resolution of the moving part is lowered is obtained. The grayscale image S1 is an image cutout unit 11 of the motion detection / extraction means 10, a difference circuit 12, and a motion compensation circuit 35.
Sent to The frame memory 31 holds the image data S16 of one frame before, and this data S16 is supplied to the motion compensation circuit 35. The motion compensation circuit 35 compares the grayscale image S1 with the image data S16 one frame before, detects the motion of the entire frame due to the motion of the camera 51, and corrects the motion, and the image data S76 one frame before. Is supplied to the difference circuit 12. Further, the motion vector S77 is the encoding circuit 22 of the image processing means 20.
Sent to

The difference circuit 12 obtains an error S7 between the grayscale image S1 and the image data S76, and the error S7 is sent to the motion judging section 13. The motion determination unit 13 determines that the portion in which the error S7 is equal to or larger than the threshold value is the moving portion, and the selection signal S78 is sent to the image cutout unit 11 so as to cut out only the moving portion. As a result, only the grayscale image S2 of the moving part is input to the compression (halftone processing) circuit 21 of the image coding means 20.

The compression circuit 21 performs the encoding process as described above, and the code string S12 is sent to the encoding circuit 22. In the encoding circuit 22, the code string S12 and the motion vector S
77 are added together, an identification bit for identifying a frame delimiter, an error correction code, etc. are added to the communication path code S1.
3 is sent to the code amount monitoring circuit 92.

In the code amount monitoring circuit 92, when the code amount to be transmitted does not exceed the upper limit defined by the communication network, the communication path code S13 is transmitted from the output terminal 2 to the outside as the transmission code S69. Further, the signal S79 for controlling the encoding parameter in order to suppress the generation amount of the channel code S13 is the halftone processing circuit 21, the motion determination unit 13, and the preprocessing circuit 1.
It is sent to 31 etc.

In the halftone processing circuit 21, the parameter of the block class determination circuit 29 of FIG. 36 is modified by the coding parameter control signal S79, and the probability of being judged for each block class is adjusted. For example, if the number of flat blocks or medium amplitude blocks is increased, the code amount decreases, and if the number of composite edge blocks is increased, the code amount increases. Alternatively, the generated code amount can be controlled by adjusting the coding parameter of the halftone processing circuit 21. For example, when the average error minimum method is used, the value of the grayscale image at a predetermined reference pixel-the weighted average value of the two values is S, and the value of the grayscale image of the processed pixel is f, and the binary value of the processed pixel is g (0 or 1) is selected such that the strain amount Z = | f−g + S | becomes small. Here, the strain amount Z = | f−g + T · S | and S are multiplied by the coefficient T. To At this time, a halftone image when the coefficient T is switched to T = 1, T = 0.5, and T = 0 is shown in FIG. From this, it can be seen that the white solid portion and the black solid portion become wider as the coefficient T becomes smaller. Therefore, as described above, when the code amount is increased / decreased according to the width of the solid white or the black solid, the generated code amount can be controlled by adjusting the coefficient T.

The motion determining unit 13 also controls the generated code amount by the threshold value for determining the moving portion, and the preprocessing circuit 131 controls the generated code amount by the weight of the previous frame and the current frame. You can do it.

FIG. 46 shows a moving picture reproducing apparatus according to the twenty-eighth embodiment which reproduces an image by receiving the code string S69 outputted from the compressing apparatus shown in FIG. Transmission code S
69 is taken in from the input terminal 121 and supplied to the communication path decoding circuit 126. In the channel decoding circuit 126, the code string S80 is read from the transmission code S69 and supplied to the reproduction circuit 120, and the motion vector S81 is read and supplied to the motion compensation circuit 127. Reproduction circuit 12
0 is indicated by a dotted line in FIG. 40, and the halftone image S75 is reproduced from the code string S80,
It is supplied to one input of the adder circuit 129.

On the other hand, the reproduced image S82 one frame before stored in the frame memory 128 is the motion compensation circuit 12
7, and the reproduced image S83 of one frame before which the motion is compensated by the motion vector S81 is supplied to the other input of the adder circuit 129.

In the adding circuit 129, a part of the reproduced image S83 is overwritten by the halftone image S75 and displayed on the display 59 as the reproduced image S5 of the current frame. The reproduced image S5 is also input to the frame memory 128 to prepare for reproduction of the next frame.

The moving picture compression / reproduction systems according to the twenty-fourth to twenty-eighth embodiments can also be applied to the picture communication system between the EWS and the PC shown in FIG. A grayscale image is captured from the camera 82 attached to the EWS 81 to the compression device described in FIG. 37 in the main body of the EWS 81. Then, the transmission code S50 is modulated by the wireless device 83 and sent to the wireless device 83 on the PC side. In the wireless device 83, the received signal is demodulated into a transmission code S51, which is taken into the reproducing device shown in FIG. Then, the reproduced image S5 is displayed on the display 59.
Will be displayed. The same applies to image transmission from the PC 86 to the EWS 81.

Next, a moving picture compression method according to the twenty-ninth to thirty-second embodiments of the present invention will be described. First, the compression method according to the 29th embodiment includes the following steps as shown in FIG. Step ST1: The data bi, j of the i-th block of the j-th frame is input from the outside, and the process proceeds to step ST2. Step ST2: If the error between the reference data ri and the data bi, j is larger than the predetermined value T, go to step ST3, otherwise go to step ST5. Here, the reference data ri is obtained as a return value when the block number i is given to ST10 which holds the past frame in advance. Step ST3: Convert the bi, j into low-gradation data ci, j and proceed to step ST4. Step ST4: The code ci, j is output, and 1 is output as a flag indicating whether or not the code is output. If the block is the last block in the frame, go to the next frame j, else go to the next block i in the frame. Step ST5: 0 is output as a flag indicating whether or not the code is output. If the block is the last block in the frame, go to the next frame j, else go to the next block i in the frame.

The moving picture compression method according to the thirtieth embodiment, as shown in FIG. 48, includes the following steps. The above-mentioned ST10 in FIG. 47 is composed of the following steps. Step ST21: An appropriate initial value, for example, 0 is set for all block numbers i of the reference data ri. It proceeds to step ST22. Step ST22: Wait for the block number i to be input. Immediately after the block number i is input, the reference data ri is output, and then the process proceeds to step ST23. Step ST23: Step ST24 if the error between the reference data ri and the data bi, j is larger than the predetermined value T.
Otherwise, the process proceeds to step ST22. Here, bi, j is block data input together with the block number i. Step ST24: Replace the reference data ri with the data bi, j. The subsequent process returns to step ST22 and repeats steps ST22 to ST24.

The moving picture compression method according to the 31st embodiment includes the following steps as shown in FIG. The above-mentioned step ST24 shown in FIG. 48 is constituted by the following step ST34. Step ST34: The reference data r i is replaced with the data c i, j inversely converted to the gradation of the original data. Where c
i, j is the result of step ST3. Subsequent processing returns to step ST22, and steps ST22 and ST2.
The process of 3 and ST34 is repeated.

The moving picture compression method according to the thirty-second embodiment, as shown in FIG. 50, includes the following steps. This is obtained by removing step ST23 from the moving picture compression method shown in FIG.

Next, the moving image reproducing method according to the 33rd embodiment has the following steps as shown in FIG. Step ST51: An appropriate initial value, for example, 0 is set for all blocks i of the data ri which is both reproduction data and reference data. It proceeds to step ST52. Step ST52: When the flag is 1, step ST5
3 and if the flag is not 1, then the next frame j if the block is the last block in the frame.
Otherwise, go to the next block i in the frame. Step ST53: Replace the reference data ri with the data ci, j. If the block is the last block in the frame, go to the next frame j, else go to the next block i in the frame.

The moving picture reproducing method according to the 34th embodiment has the following steps as shown in FIG. In the reproduction method of FIG. 51, reproduction data di, j obtained by converting the reference data ri into high gradation data is generated in ST60 separately from the reference data ri.

The moving picture reproducing method according to the thirty-fifth embodiment has the following steps as shown in FIG. In the reproducing method shown in FIG. 52, reproduced data d
An external signal is used to switch whether i, j is reference data ri converted to high gradation data or unconverted reference data ri.

As shown in FIG. 54, the reproducing method according to the 36th embodiment includes the following steps. Step ST53 of the reproducing method shown in FIG. 51 is constituted by the following step ST83. Step ST83: The reference data r i is replaced with the data c i, j converted into high gradation data.

[0129]

As described above, according to the present invention, the binarization for converting the grayscale image signal into the binarized image signal is performed at any one of the front and rear stages in the compressed signal processing loop of the moving image compression apparatus. Since the means is provided and the reconstructing means for converting the binarized image signal into the grayscale image signal is provided at any position before and after the reproduction image processing loop of the moving image reproduction device, the compression device side and the reproduction device are reproduced. It is possible to significantly reduce the amount of image data processing on either side of the apparatus, and particularly, on the compression apparatus side, the binarizing means or the reconfiguration unit is provided in the previous stage or the middle stage of the processing loop and on the reproducing apparatus side in the latter stage of the processing loop. By providing the respective means, the data storage capacity of the frame memory can be significantly reduced, and the biggest problem in image data processing can be solved.

Although the technique of performing halftone processing on image data to reduce the amount of data processing has already been implemented in the field of still image processing as described above, the present invention applies halftone processing to moving image processing. It is not simply applied to the field of processing, but uses the correlation between frames, which is unique to the field of moving image processing, to detect and extract the moving part between the preceding and following frames and perform data processing and transmission only on this motion information. Since it is not necessary to perform data processing and transmission for the still portion in the moving image, the amount of data transmission can be reduced accordingly.

Further, according to the present invention, it is possible to reproduce an image having no distortion on the boundary between the non-transmitted portion and the transmitted portion.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the basic concept of a moving image compression / reproduction system according to the present invention.

FIG. 2 is a block diagram showing a configuration of a moving picture compression apparatus according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a moving image compression apparatus according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a moving image compression apparatus according to a third embodiment of the present invention.

FIG. 5 is a block diagram showing the configuration of a moving picture compression apparatus according to a fourth embodiment of the present invention.

FIG. 6 is a block diagram showing the configuration of a moving picture compression apparatus according to a fifth embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a moving image reproducing apparatus according to a sixth embodiment of the present invention.

FIG. 8 is a block diagram showing a configuration of a moving image reproducing apparatus according to a seventh embodiment of the present invention.

FIG. 9 is a block diagram showing a configuration of a moving image reproducing apparatus according to an eighth embodiment of the present invention.

FIG. 10 is a block diagram showing the configuration of a ninth embodiment in which the moving picture compression / reproduction device according to the present invention is applied to the transmission side of a wireless communication terminal.

FIG. 11 is a block diagram showing the configuration of a tenth embodiment in which the moving picture compression / reproduction device according to the present invention is applied to the transmission side of a wireless communication terminal.

FIG. 12 is a block diagram showing the configuration of an eleventh embodiment in which the moving picture compression / reproduction device according to the present invention is applied to a portable videophone as a two-way communication terminal.

FIG. 13 is a perspective view showing a terminal appearance of a twelfth embodiment in which the moving picture compression / reproduction device according to the present invention is applied to a portable videophone as a two-way communication terminal.

FIG. 14 is a block diagram showing a configuration in which the compression devices according to the first to fifth embodiments of the present invention are integrated.

FIG. 15 is an explanatory diagram for explaining a moving region and a still region.

FIG. 16 is a block diagram showing a configuration in which the playback devices according to the sixth to tenth embodiments of the present invention are integrated.

FIG. 17 is an explanatory diagram for explaining a range of reference pixels in relation to processed pixels.

FIG. 18 is an explanatory diagram illustrating a positional relationship between a reference pixel and a motion area.

FIG. 19 is a block diagram showing a moving image compression apparatus according to an improved example of the first to fifth embodiments of the present invention.

FIG. 20 is a block diagram showing a compression device according to a thirteenth embodiment of the present invention.

FIG. 21 is an explanatory diagram for explaining the positional relationship of the binarization processing order of the motion area.

FIG. 22 is an explanatory diagram illustrating a positional relationship between a reference pixel and a motion area.

FIG. 23 is an explanatory diagram illustrating a positional relationship between a reference pixel and a motion area.

FIG. 24 is a block diagram showing a compression device according to a fourteenth embodiment of the present invention.

FIG. 25 is a block diagram showing a compression device according to a fifteenth embodiment of the present invention.

FIG. 26 is a block diagram showing a compression circuit according to a 16th embodiment of the present invention.

FIG. 27 is an explanatory diagram illustrating a range of reference pixels when vector quantization is performed.

FIG. 28 is a block diagram showing a playback device according to a seventeenth embodiment of the present invention.

FIG. 29 is an explanatory diagram showing an eighteenth embodiment in which the present invention is applied to an image communication system.

FIG. 30 is a block diagram showing a compression device according to a nineteenth embodiment of the present invention.

FIG. 31 is a block diagram showing a compression device according to a twentieth embodiment of the present invention.

FIG. 32 is a block diagram showing a compression device according to a twenty-first embodiment of the present invention.

FIG. 33 is a block diagram showing a compression device according to a 22nd embodiment of the present invention.

FIG. 34 is a block diagram showing a compression device according to a 23rd embodiment of the present invention.

FIG. 35 is a block diagram showing a compression device according to a twenty-fourth embodiment of the present invention.

FIG. 36 is a block diagram showing a compression device according to a twenty-fifth embodiment of the present invention.

FIG. 37 is a block diagram showing a copy encoding circuit according to the 24th and 25th embodiments.

FIG. 38 is a diagram showing reference blocks.

FIG. 39 is a diagram showing how blocks are integrated.

FIG. 40 is a block diagram showing a reproducing device according to a twenty sixth embodiment of the present invention.

FIG. 41 is a view showing the order of arranging the densities.

FIG. 42 is a diagram in which luminance is estimated by density.

FIG. 43 is another diagram in which luminance is estimated by density.

FIG. 44 is a block diagram showing a compression device according to a 27th embodiment of the present invention.

FIG. 45 is a halftone image when the encoding parameter is switched.

FIG. 46 is a block diagram showing a playback device according to a 28th embodiment of the present invention.

FIG. 47 is a flowchart showing a compression method according to a 29th embodiment of the present invention.

FIG. 48 is a flowchart showing a compression method according to the thirtieth embodiment of the present invention.

FIG. 49 is a flowchart showing a compression method according to the 31st embodiment of the present invention.

FIG. 50 is a flowchart showing a compression method according to the 32nd embodiment of the present invention.

FIG. 51 is a flowchart showing a reproducing method according to the 33rd embodiment of the present invention.

FIG. 52 is a flowchart showing a reproducing method according to the 34th embodiment of the present invention.

FIG. 53 is a flowchart showing a reproducing method according to the 35th embodiment of the present invention.

FIG. 54 is a flowchart showing a reproducing method according to the 36th embodiment of the present invention.

FIG. 55 is a block diagram showing the configuration of a conventional moving image compression apparatus.

FIG. 56 is a block diagram showing the configuration of a conventional moving image reproducing apparatus.

[Explanation of symbols]

 10 motion detection / extraction means 20 image coding means 21 halftone processing means (binarization circuit) 22 coding circuit 30 reference image generation means 31 storage means (frame memory) 32 decoding circuit 33 synthesis circuit 34 reconfiguration circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihiro Kikuchi Komukai-shi, Kawasaki-shi, Kanagawa 1 Komachi Toshiba-cho, Toshiba Corporation R & D Center (72) Inventor Noboru Yamaguchi Small, Saiwai-ku, Kawasaki-shi, Kanagawa Muko Toshiba-cho 1 Stock Company Toshiba R & D Center (72) Inventor Ken Nakajo 1 Komukai Toshiba-cho 1 Stock Company Toshiba R & D Center

Claims (20)

[Claims] 1. A reference image generating means for outputting a reference image signal for displaying a first frame of an input image signal; comparing the reference image signal with a second frame of the input image signal for the input. A motion detecting / extracting means for generating a differential signal for displaying a moving area of the image signal; and an image coding means for coding the differential signal to generate a coded image signal having a resolution lower than the differential signal. A moving picture compression / reproduction system comprising a moving picture compression apparatus provided. 2. The reference image generating means stores one frame of the input image signal and outputs the stored frame as the reference image signal; and the storage means generates the motion detecting / extracting means. A synthesizing unit for synthesizing the difference signal with the reference image signal to generate a synthesizing signal for displaying the next one frame to be stored in the storing unit; The moving image compression / reproduction system according to claim 1. 3. The reference image generation means, decoding means for decoding the coded image signal into the differential signal; storage means for storing one frame of the input image signal; generation by the decoding means. The moving image compression apparatus further comprising: a combining unit configured to combine the generated difference signal with a frame stored in the storage unit to generate a combined signal for displaying a next frame to be stored in the storage unit. The moving picture compression / reproduction system according to claim 1, comprising: 4. The storage means includes a moving image compression apparatus, which stores one frame of the input image signal and includes storage means for outputting the reference image signal based on the stored frame. The moving picture compression / reproduction system according to claim 1. 5. Storage means for storing a reference frame of a predecoded image signal; a reference image signal for displaying the reference frame stored in the storage means, and a motion area of the encoded image signal. A moving image compression / reproduction system, comprising: a halftone-encoded moving image reproduction device, which is configured to combine a differential signal to be displayed to obtain a decoded image signal. 6. Storage means for storing a reference frame of a pre-decoded image signal; and the reference frame stored in the storage means, combined with a differential signal for displaying a motion area of the encoded image signal. And a converting means for converting the decoded image signal into an image signal having a resolution higher than that of the decoded image signal;
A moving image compression / reproduction system including a moving image reproduction device including the following. 7. A moving image reproducing apparatus further comprising a selecting means for selectively outputting the decoded image signal and a high resolution image signal according to the display resolution of the display device. 6. The moving image compression / reproduction system according to item 6. 8. A first display for displaying a motion area of a coded image signal
Conversion means for converting the differential signal of 1 to a second differential signal having a resolution higher than that of the first differential signal; storage means for storing a reference frame of a predecoded image signal;
A moving image reproducing apparatus comprising: a reference image signal for displaying a reference frame stored in the storage unit, and a combining unit for combining the second differential signal having a high resolution to generate a decoded image signal. A moving image compression / reproduction system comprising: 9. A step of outputting a reference image signal corresponding to a first frame of the input image signal; comparing the reference image signal with a second frame of the input image signal, the input image A moving image compression for compressing a moving image by generating a differential signal for displaying a motion region of the signal; encoding the differential signal to generate an encoded image signal having a resolution lower than the differential signal; A method for compressing and reproducing a moving image, which includes a method. 10. The step of generating the reference image includes the step of storing one frame of the input image signal and outputting the stored frame as the reference image signal; the difference signal being the reference image signal. 10. The moving image compression and reproduction method according to claim 9, further comprising the step of: synthesizing the moving image and a synthetic signal for displaying the next one frame to be stored in the storing step. Method. 11. The step of generating the reference image, the step of decoding the coded image signal into the difference signal; the step of storing one frame of the input image signal; the step of storing the difference signal 10. The moving image compression method according to claim 9, further comprising the step of: synthesizing with the frame stored in the step of generating a combined signal for displaying the next frame to be stored. How to play. 12. The storing step of storing the input image in frame units includes a step of storing one frame of the input image signal and a step of outputting the reference image signal based on the stored frame. The moving picture compression / reproduction method according to claim 9, further comprising a moving picture compression method provided. 13. A storage step of storing a reference frame of a predecoded image signal; a reference image signal for displaying the reference frame stored in said storage means; and a motion area of the encoded image signal. And a signal synthesizing step for synthesizing a differential signal to be displayed to obtain a decoded image signal, and a moving image reproducing method for decoding a halftone encoded moving image by :. 14. A storage step of storing a reference frame of a predecoded image signal; combining the reference frame stored in the storage means with a differential signal for displaying a motion area of the encoded image signal. And a signal converting step of converting the decoded image signal into an image signal having a resolution higher than that of the decoded image signal. Characteristic moving image compression and reproduction method. 15. A moving image reproducing method further comprising a selecting step of selectively outputting the decoded image signal and a high resolution image signal according to a display resolution of a display device. 15. The moving image compression / reproduction method according to item 14. 16. A signal conversion step of converting a first differential signal representing a moving area of an encoded image signal into a second differential signal having a resolution higher than that of the first differential signal.
A storage step of storing a reference frame of a pre-decoded image signal; a reference image signal displaying the reference frame stored by the storage step; and the second resolution having the high resolution converted by the signal conversion step. And a signal synthesizing step of synthesizing a differential signal to generate a decoded image signal. 17. A motion image signal transmission unit that encodes an input motion image in frame units and outputs it as an image coded signal, and an image that decodes the input image coded signal and outputs it as a reproduced image signal. In a moving image wireless signal transmitting / receiving system including a signal receiving unit, the moving image signal transmitting unit outputs a reference image signal for displaying a first frame of the input image signal; ,
Motion detection / extraction means for generating a differential signal for displaying a moving region of the input image signal as compared to the second frame of the input image signal; encoding the differential signal for a lower resolution than the differential signal Image coding means for generating a coded image signal having: and a moving picture compression device, wherein the moving picture signal receiving unit includes a storage means for storing a reference frame of a predecoded image signal; A synthesizing unit for synthesizing a reference image signal for displaying the reference frame stored in the storage unit and a differential signal for displaying a motion region of the encoded image signal to obtain a decoded image signal; A moving picture signal transmitting / receiving system comprising a tone coding moving picture decoding device. 18. A moving image signal transmission unit that encodes an input moving image in frame units and outputs it as an image encoded signal, and an image that decodes the input image encoded signal and outputs it as a reproduced image signal. In the moving image wireless signal transmission / reception system including a signal reception unit, the image signal transmission unit includes reference image generation means for outputting a reference image signal for displaying a first frame of the input image signal;
Motion detection / extraction means for generating a differential signal for displaying a moving region of the input image signal as compared to the second frame of the input image signal; encoding the differential signal for a lower resolution than the differential signal Image coding means for generating a coded image signal having: and a storage means for storing a reference frame of a predecoded image signal, the moving picture compression device. Synthesizing means for synthesizing the reference frame stored in the storage means with a differential signal for displaying a motion area of the encoded image signal to obtain a decoded image signal; and the decoded image signal for the decoded image. A moving image wireless signal transmission / reception system, comprising: a moving image reproducing apparatus including; 19. A moving image signal transmitting unit for encoding an input moving image in frame units and outputting it as an image encoded signal, and a moving image for decoding the input image encoded signal and outputting it as a reproduced image signal. In a moving image wireless signal transmitting / receiving system including an image signal receiving unit, the moving image signal transmitting unit outputs a reference image signal for displaying a first frame of the input image signal, and the reference image signal. To
Motion detection / extraction means for generating a differential signal for displaying a moving region of the input image signal as compared to the second frame of the input image signal; encoding the differential signal for a lower resolution than the differential signal Image coding means for generating a coded image signal having: and the moving image signal receiving unit, wherein the moving image signal receiving unit has a high resolution according to the decoded image signal and the display resolution of the display device. 19. The moving image wireless signal transmitting / receiving system according to claim 18, further comprising a moving image reproducing apparatus further comprising a selecting means for selectively outputting the image signal. 20. A moving image signal transmitting unit that encodes an input moving image on a frame-by-frame basis and outputs it as an image encoded signal, and a decoding unit that inputs the image encoded signal and outputs it as a reproduced image signal. In a moving image wireless signal transmitting / receiving system including a moving image signal receiving unit, the moving image signal transmitting unit outputs a reference image signal for displaying a first frame of an input image signal, and the reference image. Signal
Motion detection / extraction means for generating a differential signal for displaying a moving region of the input image signal as compared to the second frame of the input image signal; encoding the differential signal for a lower resolution than the differential signal Image coding means for generating a coded image signal having: and the moving image signal receiving unit, wherein the moving image signal receiving unit includes a first differential signal for displaying a moving region of the coded image signal, Conversion means for converting into a second difference signal having a resolution higher than that of the first difference signal; storage means for storing a reference frame of a previously decoded image signal; reference stored in the storage means A moving picture decoding apparatus comprising: a synthesizing unit for synthesizing a reference image signal for displaying a frame and the second differential signal having a high resolution to generate a decoded image signal. Motion picture radio signal transmission and reception system according to.