JP2743827B2 - Digital video compression transmission system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital video compression transmission system for compressing and transmitting an input video.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing a conventional example of this type of moving picture digital compression transmission system. This moving image digital compression transmission system includes a block dividing unit 201 for generating a blocked image obtained by dividing an input moving image into N × N block images, and a block dividing unit 201.
Subtracter 20 for subtracting the divided image from the previous image and the divided image of the previous frame for each block image, and outputting an inter-frame difference.
2 and an orthogonal transform unit 206 for orthogonally transforming the difference between frames.
When an encoding unit 207 to output to the transmission path encoding the output of the orthogonal transform unit 206, with respect to the orthogonal transform unit 206 and the coding unit 207 performs the respective adverse decrypted 208 and inverse orthogonal A conversion unit 209, and a previous frame storage unit 2 for further storing a difference between the block images of the previous frame
12 are provided.

[0003]

In this conventional moving picture digital compression transmission system, processing up to motion calculation is executed uniformly for all block pictures of the inputted moving picture, and the processing is performed in the input picture. If there is a stationary part, motion calculation is also performed on the stationary part and the result is constantly transmitted,
This causes an increase in transmission information.

SUMMARY OF THE INVENTION [0004] In view of the above problems, it is an object of the present invention to provide a moving picture digital compression transmission system that performs motion calculation and transmission processing only on a moving portion and does not increase transmission information.

[0005]

A moving image digital compression transmission system according to the present invention comprises: a block dividing section for generating a divided image obtained by dividing a moving image of each input frame into block images in a matrix; Means for allocating a part and a stationary part, means for orthogonally transforming a moving part, means for further encoding the output thereof, and
Orthogonal transform , inverse orthogonal transform that performs a completely opposite operation to encoding
Conversion, and decrypt comprises means includes means for calculating a motion compensation value from the difference between the previous frame and the current frame image has means for further storing the previous frame, frame difference detection for each block Is a digital video compression and transmission system that compresses and transmits information, and has means for managing the mixed state when a moving part and a stationary part are mixed in one screen. The information is compressed using the difference, and the stationary part is excluded from transmission processing in advance.

In the moving picture digital compression transmission method according to the present invention, a block dividing section for generating a divided image obtained by dividing a moving picture of each input frame into block images in a matrix form, and a divided image of a previous frame are stored. Difference calculation for calculating the difference between the divided image of the current frame from the block dividing unit and the divided image of the previous frame from the previous frame storing unit for each block image, and outputting inter-frame difference data , A moving / still management unit that stores the moving part and the still part of the divided image of the previous frame as a map in block image units, and changes the stored map according to a map change instruction. The divided image of the frame and the inter-frame difference data from the difference calculation unit are input, and according to the map of the motion / stationary management unit,
A motion / still portion allocating unit that outputs inter-frame difference data corresponding to a moving portion as motion difference data, and outputs a block image of the current frame corresponding to a still portion as a still block image, and a motion / still portion as a still block image A still-part motion calculating unit that calculates a motion amount of a still part from a difference between the block image output from the sorting unit and the corresponding block image of the previous frame; a compressed transmission signal obtained by orthogonally transforming and coding the motion difference data generates a transmission signal encoding means for sending to the transmission line, a transmission signal recovery <br/> Goka means for generating a motion difference data Replace the compressed transmission signal, the previous frame from the previous frame store adding means for adding the motion difference data from the divided image and the transmission signal decrypt means, pressurizing the divided image of the previous frame from the previous frame store A motion compensation value calculation unit for calculating a motion compensation value from the addition result of the unit, the motion compensation value calculated is regarded as the motion part stationary portion equal to or smaller than the compensation threshold, the motion amount of the stationary portion movement amount If the threshold value is greater than or equal to the threshold value, a stationary portion is regarded as a moving portion, and a comparator is provided for instructing the motion / stationary management section to change the map.

Preferably, the transmission signal encoding means includes:
An orthogonal transform unit for orthogonally transforming the motion difference data, and an encoding unit for encoding the orthogonally transformed motion difference data to generate the compressed transmission signal, wherein the transmission signal decoding unit includes the compressed transmission signal And a de-orthogonal transform unit for de-orthogonal transforming the decompressed compressed transmission signal to return to the motion difference data. A motion calculation storage unit that stores the divided images, a difference detection unit that detects a difference between the still block image and the corresponding block image of the previous frame,
And a difference value calculation unit that calculates a difference value between the block images for which the difference is detected by the difference detection unit and outputs the difference value as a motion amount of the still part.

[0008]

According to the map of the motion / stationary management section, the motion / stationary section allocating section discriminates between the moving section and the stationary section, and compresses and transmits only the moving section by the transmission signal encoding means. In addition, the comparator compares the calculation results of the still part motion calculation unit and the motion compensation value calculation unit with a threshold value, and detects a change from a moving part to a still part or from a still part to a moving part for each frame. Thus, the map of the motion / stationary management unit can be automatically reconfigured as appropriate to the current situation.

[0009]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a moving picture digital compression transmission system according to the present invention. FIG.

The block dividing section 1 outputs an input moving image as a divided image obtained by dividing the moving image into N × N matrix block images. The subtracter 2 subtracts the divided image from the block dividing unit and the divided image of the previous frame for each block image, and outputs a difference. The moving / still part allocating unit 3 receives the divided image from the block dividing unit 1 and the difference from the subtractor 2 and determines which block image of the divided image is a moving part and which block image is a stationary part in the previous frame. The motion / stationary part management unit that manages the data as a map as a map In response to an instruction from the motion / stationary management unit 4, the difference data corresponding to the moving part is transmitted to the orthogonal transformation unit 6, and the block image corresponding to the stationary part is obtained. Are output to the still-partial-motion calculating unit 5, respectively. Orthogonal transform unit 6
Performs orthogonal transform on the data input from the moving / stationary partial sorting unit 3 and outputs the data to the encoding unit 7. The encoding unit 7 encodes the input data and outputs the encoded data to a transmission path.

[0011] decrypt unit 8, decrypt the data encoding unit 7 is output to the transmission path, decrypted data to inverse orthogonal transform inverse orthogonal transform unit 9, the orthogonal transform unit 6 moves / The difference data is returned to the difference data input from the stationary part distribution unit 3. Adder 1
0 adds the difference data from the inverse orthogonal transform unit 9 and the divided image of the previous frame output from the previous frame storage unit 12 to generate a current frame and outputs it to the motion compensation value calculation unit 11. The motion compensation value calculation unit 11 includes a previous frame storage unit 12
The motion compensation value corresponding to the difference between the divided image of the previous frame and the divided image of the current frame is calculated and output to the comparator 13.

As shown in FIG. 2, the stationary partial motion calculation section 5 includes a previous frame storage section 51, a difference detection section 52, and a difference value calculation section 53. The difference detection unit 52 compares the still portion of the current frame input from the motion / still portion distribution unit 3 with the corresponding block image from the previous frame storage unit 51. The difference value calculation unit 53 calculates a difference value from the result and outputs the difference value to the comparator 13.

The comparator 13 compares the motion compensation value from the motion compensation value calculation unit 11 with a compensation threshold, and when the value becomes equal to or smaller than the compensation threshold, the block image is changed from a motion part to a stationary part. The motion / stillity management unit 4 is notified. Further, the comparator 13 compares the difference value from the difference value calculation unit 53 of the still part motion calculation unit 5 with the difference threshold, and when the difference value exceeds the difference threshold, changes the block image from the still part to the movement part. To the motion / stationary management unit 4 as described above. The motion / stationary management unit 4 changes the map of the motion / stationary part based on these notifications.

In the above embodiment, an input moving image is divided into block images. However, it is needless to say that this division may be divided into small areas such as pixels.

[0015]

As described above, in order to reduce the amount of transmitted information, the moving picture digital compression transmission system according to the present invention distinguishes between a moving part and a stationary part and transmits only the moving part, When the map between the moving part and the stationary part changes, the transmission information amount can be reduced by appropriately resetting the moving part and the stationary part.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a moving picture digital compression transmission system according to the present invention.

FIG. 2 is a block diagram showing a still-part motion calculating unit 5 in the embodiment of FIG. 1 in detail.

FIG. 3 is a block diagram showing a conventional example.

[Explanation of symbols]

1 block dividing unit 2,51 subtracter 3 motion / stationary part sorting unit 4 motion / still managing unit 5 the stationary portion movement calculating section 6 orthogonal transformation section 7 coding section 8 decrypted portion 9 inverse orthogonal transform unit 10 adder 11 Motion compensation value calculation unit 12, 52 Previous frame storage unit 13 Comparator 53 Difference detection unit 54 Difference value calculation unit

Claims (3)

(57) [Claims] 1. A block dividing unit that generates a divided image obtained by dividing a moving image of each input frame into block images in a matrix, a previous frame storage unit that stores divided images of a previous frame, and a block dividing unit. A difference calculator for calculating the difference between the divided image of the current frame from the previous frame and the divided image of the previous frame from the previous frame storage unit for each block image, and outputting inter-frame difference data; And a still portion are stored as a map in block image units, and a motion / still management unit that changes the stored map in accordance with a map change instruction, a divided image of the current frame from the block division unit, and a frame from the difference calculation unit And the inter-frame difference data corresponding to the moving part is input as the motion difference data according to the map of the motion / stationary management unit. A motion / still portion allocating unit that outputs a block image of the current frame corresponding to a still portion as a still block image, a block image output from the motion / still portion allocating unit as a still block image, and A stationary part motion calculator for calculating a motion amount of a stationary part from a difference from a block image of a frame; and a transmission signal encoding unit for orthogonally transforming and encoding the motion difference data to generate a compressed transmission signal and sending the compressed transmission signal to a transmission path When a transmission signal decrypted means for generating a motion difference data Replace the compressed transmission signal, and a motion difference data from the transmission signal decrypted means and divided image of the previous frame from the previous frame store adder A motion compensation value calculation unit that calculates a motion compensation value from the divided image of the previous frame from the previous frame storage unit and the addition result of the addition unit. If calculated motion compensation value is less compensated threshold considered a moving portion and a stationary portion, the movement amount of the stationary portion is regarded as partial motion of the stationary part if the above movement amount threshold value, the motion / still manage And a comparator for instructing the unit to change the map. 2. The transmission signal encoding means comprises : an orthogonal transform unit for orthogonally transforming motion difference data; and an encoding unit for encoding the orthogonally transformed motion difference data to generate the compressed transmission signal. the transmission signal decrypt unit from a decrypt unit for decrypt the compressed transmission signal, an inverse orthogonal transformation unit which performs inverse orthogonal transformation to compressed transmission signal decrypted back into the movement difference data 2. A moving picture digital compression transmission system according to claim 1. 3. A motion detecting storage unit for storing a divided image of a previous frame, a difference detection unit for detecting a difference between a still block image and a corresponding block image of the previous frame. And a difference value calculation unit that calculates a difference value between the block images for which the difference detection unit has detected the difference, and outputs the difference value as a motion amount of the still part.
Or a digital video compression transmission system according to 2.