JPH08223480A - Device for adding special effect to compressed moving image - Google Patents

Abstract

PURPOSE: To attain on an image wipe effect by using inter-frame correlation and applying edit to a moving image signal subject to compression coding in the unit of blocks so as to suppress image quality deterioration due to edit. CONSTITUTION: A composition control means 13 selects witches 3, 4 in the unit of blocks to output a wipe pattern being a composition of compressed moving images A, B. When a prediction block around wipe border line directions from a compression moving image before the composition differs from that after conpositing, non-compression image stored in frame memories 6, 7 is used. A coding means 9 converts a block including the wipe border line into a compressed image. A switch 11 selects an image image of an output buffer 10 as to a block not including the wipe border line and selects an image signal of the coding means 9 as to a block including the wipe border line. Thus, the system has less image quality deterioration in comparison with the system where the whole pattern is expanded, edited and then compressed again.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compressed moving image special effect device for applying a wipe effect to a moving image differentially encoded between frames.

[0002]

2. Description of the Related Art A conventional image special effect device is intended for an uncompressed moving image signal. In the case of an uncompressed signal, even if the image signal is output with the wipe effect applied, the image quality deterioration does not matter and the signal format does not change. On the other hand, in order to apply the wipe effect to the compressed moving image signal using the correlation between frames using the conventional image special effect device, the correlation between the compressed image signals is not used once. It is converted to a compressed moving image signal and then input to the image special effect device. Then, the image to which the special effect is added needs to be compressed and encoded again.

[0003]

However, when an image signal that has been compression-encoded with a high compression rate is decoded and then compression-encoded again, problems such as deterioration in image quality and increase in code amount are generally encountered. Occurs.

The present invention has been made in view of the above-mentioned conventional problems, and an image obtained by using wipe for a moving image signal compression-coded in block units by using the correlation between frames. An object of the present invention is to realize a compressed moving image special effect device capable of suppressing image quality deterioration due to editing when performing editing.

[0005]

According to the invention of claim 1 of the present application, a frame image is divided into blocks of m × n (m and n are natural numbers) pixels, and each block is intra-frame encoded or a past frame. For each of the first and second compressed moving image signals that have been forward-predictively coded using the difference from the prediction block for Sequentially synthesized based on
A compressed moving image special effect device for outputting a compressed moving image signal subjected to a wipe effect, the first input buffer temporarily holding the first compressed moving image signal, and the second compressed moving image signal temporarily held. A second input buffer, a decoding means for decoding the first or second compressed moving image signal held in the first or second input buffer into an uncompressed frame image signal, and decoding by the decoding means A first frame memory for temporarily holding the converted first image signal in frame units; a second frame memory for temporarily holding the second image signal decoded by the decoding means in frame units; Second image signal
When wiping with the image signal of, the wiping input means for inputting the wiping pattern and the wiping speed, the wiping line in the output block of the current frame, and the wiping line in the block of the previous frame corresponding to the output block of the current frame. The first and second corresponding to the output block when
Encoding means for reading out the image signal of (1) from the first and second frame memories, creating a composite block based on the wipe line of the wipe input means, and encoding the image signal of the composite block in the same system as the input compressed moving image signal. An output buffer for switching and temporarily holding the first or second compressed moving image signal held in the first or second input buffer, and a continuous wipe when the wipe pattern and the wipe speed are input from the wipe input means. The position of the wipe line of each frame is specified, and when the wipe line is included in the output block of the current frame and when the wipe line is included in the block of the previous frame corresponding to the output block of the current frame, The image signal of the encoding means is output as the image signal, and the output block of the current frame does not include the wipe line, and the output block of the current frame is output. When not included wipe lines in the block of the previous frame corresponding to the click, it is characterized in that it comprises a and a synthesis control means for outputting an image signal of the output buffer as an image signal of the output block.

According to the invention of claim 2 of the present application, from the start of wipe to the end of wipe, either one of the first and second compressed moving image signals is held as a still image, and there is no difference in the image signal between frames. And a zero-difference block signal generation means for instructing the synthesis control means to switch to a zero-difference block signal and output it as an image signal of the output block. Is.

According to the invention of claim 3 of the present application, when each block of the input compressed moving image signal is either intraframe coded, forward predictive coded, or bidirectional predictive coded, When the frames of the first and second compressed moving image signals are combined in the reproduction order one frame at a time from the start frame to the end frame of the wipe, the backward predictive coding or the bidirectional predictive coding signal is applied to one of the compressed moving picture signals. Is included, the other compressed moving picture signal includes backward predictive coding or bidirectional predictive coding, and one compressed moving picture signal includes either backward predictive coding or bidirectional predictive coding. When the other compressed video signal is not included, the synthesizing control means inputs the first or second input buffer so that neither the backward predictive coding nor the bidirectional predictive coding is included in the other compressed moving image signal. Control It is characterized in that.

[0008]

According to the present invention having such characteristics, the frame image is divided into blocks of m × n (m and n are natural numbers) pixels, and each block is subjected to intraframe coding or forward prediction coding. It is assumed that the first and second compressed moving image signals being performed are input. Then, the first and second input buffers temporarily hold the first and second compressed moving image signals, respectively. Next, the decoding means decodes the first or second compressed moving image signal held in the first or second input buffer into an uncompressed frame image signal. The first and second frame memories temporarily hold the first and second image signals decoded by the decoding means in frame units, respectively. When the wipe pattern and the wipe speed are input to the wipe input unit, when the wipe line is included in the output block of the current frame and when the wipe line is included in the block of the previous frame corresponding to the output block of the current frame, the code The converting means reads the first and second image signals corresponding to the output block from the first and second frame memories. Then, the encoding means creates a combined block based on the wipe line of the wipe input means, and encodes the image signal of the combined block in the same manner as the input compressed moving image signal. On the other hand, the output buffer switches and temporarily holds the first or second compressed moving image signal held in the first or second input buffer. Further, the composition control means indicates the position of the wipe line of each successive frame. When the output block of the current frame includes a wipe line, and when the block of the previous frame corresponding to the output block of the current frame includes a wipe line, the synthesis control means uses the image signal of the encoding means as the image signal of the output block. Is output. And the wipe block is not included in the output block of the current frame,
When the wipe line is not included in the block of the previous frame located at the same position as the output block of the current frame, the synthesis control means outputs the image signal of the output buffer as the image signal of the output block.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A compressed moving image special effect device according to a first embodiment (claim 1) of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing the configuration of the compressed moving image special effect device of the first embodiment. In the figure, the compressed moving image input buffer 1 is a buffer for temporarily storing the compressed moving image signal A. The compressed moving image input buffer 2 is a buffer that temporarily stores the compressed moving image signal B. The switch 3 is a switch for switching the output of the compressed moving image input buffer 1 or 2, and this switching control signal is given by the synthesizing control means 13 described later. The switch 4 is also a switch for switching the output of the compressed moving image input buffer 1 or 2, and the switching control signal is given by the synthesis control means 13.

The output of the switch 3 is given to the decoding means 5, and the output of the switch 4 is given to the output buffer 10. The decoding means 5 is means for expanding the compressed moving image signal output from the switch 3 into an uncompressed moving image signal, and its output is given to the frame memory 6 or 7 and the synthesizing control means 13. The frame memories 6 and 7 are memories that store the image signal output by the decoding means 5 via the switch 8. The switch 8 cuts the output of the decoding means 5 to the frame memory 6 or 7 at the time of storing the image signal and outputs it, and switches the output of the frame memory 6 or 7 at the time of reading the image signal to output to the coding means 9. It is a thing.

The encoding means 9 MP the decoded image signal.
It is a means for performing compression coding again by EG or the like. The output buffer 10 is a buffer that temporarily stores the compressed moving image signal output from the switch 4. The switch 11 is a switch for selecting either the output signal of the encoding means 9 or the output signal of the output buffer 10, and the switching control signal is given from the synthesis control means 13.

The input means 12 is means for inputting the wipe pattern and the transition time of the wipe and giving them to the synthesis control means 13. The synthesizing control means 13 is means for outputting a switching control signal to the switches 3, 4, 8 and 11, respectively, based on the input wipe pattern, transition time and the like.

The operation of the compressed moving image special effect apparatus of the first embodiment thus constructed will be described with reference to FIG. The compressed moving image signal A input to the compressed moving image input buffer 1 and the compressed moving image signal B input to the compressed moving image input buffer 2 are both configured by an intra-frame coding screen or a forward prediction coding screen. Suppose Figure 2 here
The operation of switching the compressed moving image signal from A to B by wiping as shown in FIG.

First, the synthesizing control means 13 switches the switch 3 to the compressed moving image input buffer 1 side, and at the same time, the switch 8
To the frame memory 6 side. The decoding means 5 decodes the signal of one frame of the input compressed moving image signal A into an uncompressed image signal and stores it in the frame memory 6. Next, the composition control means 13 switches the switch 3 to the compressed moving image input buffer 2 side, and at the same time switches the switch 8 to the frame memory 7 side. The decoding means 5 decodes the signal of one frame of the input compressed moving image signal B into an uncompressed image signal and stores it in the frame memory 7. Here, if the input compressed moving image is encoded by using motion compensation, the value of the motion vector is output to the synthesis control unit 13.

Next, the switching operation of the switches 4, 8 and 11 will be described with reference to FIG. The screen F3 in the figure is
One frame is in the process of switching from the compressed moving image signal A to B, and the lower right part of the wipe boundary line L3 is the compressed moving image signal A,
The upper left of the wipe boundary line L3 is the compressed moving image signal B. The synthesizing control means 13 compares the pattern of the screen block division at the time of encoding the compressed moving image with the synthesizing pattern of the two wipe screens. Then, when the positions of the blocks to be output from now on are all included in the range of the image A in the combined screen, and the blocks are differentially encoded with the blocks of the previous frame, If the pixels of the entire range of the block used for the differential encoding are included in the compressed moving image output by the compressed moving image special effect device, the switch 4 is switched to the compressed moving image input buffer 1 side. The signal of one block of the compressed moving image signal A output from the switch 4 is written in the output buffer 10.

Similarly, when the positions of the blocks to be output from now on are all included in the range of the image B on the combined screen, and the blocks have been differentially encoded with the blocks of the previous frame. If the pixels of the entire range of the block used for the differential encoding are included in the compressed moving image output by the compressed moving image special effect device,
The synthesizing control means 13 switches the switch 4 to the compressed moving image input buffer 2 side. A signal of one block of the compressed moving image signal B output from the switch 4 is written in the output buffer 10.

When the block is differentially encoded with the block of the previous frame, the pixels of the entire range of the block used for the differential encoding are the compressed dynamic image output by the compressed dynamic image special effect device. If not included, the synthesis control means 13 switches the switch 8. If the block to be output is the moving image A, the image signal at the block position of the image signal written in the frame memory 6 is output to the encoding means 9. If the block to be output is the moving image B, the image signal at the block position of the image signal written in the frame memory 7 is output to the encoding means 9.

When the position of the block to be output from now on extends over the range of the image A and the image B on the combined screen, the combining control means 13 switches the switch 8 and writes it in the frame memories 6 and 7. The pixel signals at the relevant block position of the image signal being displayed are combined in the same pattern as the screen synthesis pattern and output to the encoding means 9. The coding means 9 performs coding without using a difference for each block, and switches the coded image signal to the switch 1.
Output to 1.

In the example of the block of FIG. 2, at the position of the block i where the differential encoding with the previous frame is not performed, the switch 4 is switched to the compressed moving image input buffer 2 side,
The block of the compressed moving image signal B is written in the output buffer 10. At the position of the block j where the differential encoding with the previous frame is not performed, the switch 4 is switched to the compressed moving image input buffer 1 side, and the block of the compressed moving image signal A is written in the output buffer 10.

Consider a block k on the screen F3 which is located at the position of the block k'of the image B on the screen F2 and which has been subjected to differential encoding with this block. Block k'of screen F2
Since the entire range of is not included in the image B, the image signal at the position of the block k is read from the frame memory 7,
Encoding is performed by the encoding means 9.

At the position of the block m on the screen F3, since both the image A and the image B are included, the frame memory 6
Then, the image signal at the position of block m is read from the frame memory 7 and encoded by the encoding means 9.

Finally, the synthesizing control means 13 switches the switch 11 so that the order of the outputted blocks is the same as the inputted compressed moving picture signal, and the compressed moving picture outputted by the coding means 9 and the output buffer 10 is outputted. The image signal is output in block units. By performing this operation for each frame during the transition period of the wipe, a compressed moving image in which the moving image A is switched to the moving image B by the wipe can be output.

The compressed moving image signal A input to the compressed moving image input buffer 1 and the compressed moving image signal B input to the compressed moving image input buffer 2 are coded in the intra-frame and forward predictive coding. Consider a case where not only the screen but also the bidirectional predictive coding screen in which the predictive coding is performed using the future screen is inserted. In this case, for example, it is assumed that only the intra-frame coding screen and the forward prediction coding screen include the reference block, and as shown in FIG. 3, when one compressed moving image signal includes the bidirectional prediction coding signal. ,
The synthesis control means 13 controls the inputs of the compressed moving image input buffers 1 and 2 so that the other compressed moving image signal does not include intraframe coding or forward prediction coding. By thus combining the screens in correspondence with each other, it is possible to output a compressed moving image that is switched by a wipe.

Next, a compressed moving image special effect device according to a second embodiment (claim 2) of the present invention will be described with reference to FIG. FIG. 4 is a block diagram showing the configuration of the compressed moving image special effect device of the second embodiment. The same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. In addition to the configuration of the first embodiment, a zero difference block signal generating means 14 is added to the compressed moving image special effect device of the present embodiment.

The zero-difference block signal generating means 14 is means for outputting a compressed image signal for one block, which means that it is the same block image as the past frame, and this compressed image signal is given to the switch 11. Switch 11
Switches the output of the encoding means 9, the output buffer 10, or the zero difference block signal generation means 14 based on the switching control signal of the synthesis control means.

Regarding the operation of the compressed moving picture special effect apparatus of the second embodiment configured as above, the compressed moving picture signal A inputted to the compressed moving picture input buffer 1 and the compressed moving picture input buffer 2 are inputted. The compressed moving image signal B is composed of the intra-frame predictive coding screen and the forward predictive coding screen, and the operation when the compressed moving image signal is switched from A to B by wipe will be described.

When the compressed moving image signal is switched from A to B by wiping as shown in FIG. 2, just before the transition starts,
The synthesizing control means 13 switches the switch 3 to the compressed moving image input buffer 1 side, and at the same time switches the switch 8 to the frame memory 6 side. The decoding means 5 decodes the signal of one frame immediately before the transition of the input compressed moving image signal A into an image signal, and stores this image signal in the frame memory 6. In this embodiment, this frame memory is not rewritten during the transition.

Next, the composition control means 13 switches the switch 3 to the compressed moving image input buffer 2 side, and at the same time the switch 8
To the frame memory 7 side. The decoding means 5
A signal for one frame of the input compressed moving image signal B is decoded into a signal, and this image signal is stored in the frame memory 7. Here, if the input compressed moving image is encoded by using motion compensation, the value of the motion vector is output to the synthesis control unit 13.

Next, the switching operation of the switches 4, 8 and 11 will be described. First, the composition control means 13 compares the pattern of screen block division at the time of encoding the compressed moving image with the composition pattern of the two wipe screens. If the positions of the blocks to be output from now on are all included in the range of the image A on the combined screen, the switch 11
Is switched to the zero difference block signal generating means 14 side, which means that the block image is the same as the past frame.
A compressed image signal for a block is output from the switch 11.

Further, the positions of the blocks to be output from now on are all included in the range of the image B on the combined screen, and the image A and the image B on the combined screen.
If the range is over, the switching operation of each switch is performed in the same manner as in the first embodiment.

By doing so, the image A becomes a still screen during the transition time, and it is possible to output a compressed moving image signal having a smaller data amount than in the case of forming a moving image. Here, the example in which the moving image A is set as the still screen during the transition is shown, but the moving image B is set as the still screen, or the still screen is switched from B to A in the middle of the wipe transition time. May be.

In the first and second embodiments, an example has been described in which the compressed moving image signal A is switched to the compressed moving image B, but it goes without saying that it is also possible to switch from B to A. Although only one encoding means and one decoding means are used, two or more encoding means and two or more encoding means and decoding means may be used for each input compressed moving image signal. Good.

[0033]

As described above, according to the present invention, only a part of the wipe screen becomes a re-encoded block, and the blocks of other parts output the input compressed moving image signal as they are, so that the wipe effect is obtained. It is possible to minimize the deterioration of the image quality due to the above. Moreover, since the original compressed moving image is used as it is for the edited compressed moving image of the wipe image effect, the image quality is less deteriorated as compared with the method of editing the entire screen, then editing and then compressing again. effective.

[Brief description of drawings]

FIG. 1 is a block diagram of a compressed moving image special effect device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing types of blocks in an image combined by wiping.

FIG. 3 is an explanatory diagram showing a method of handling a compressed moving image using a future frame for predictive coding.

FIG. 4 is a block diagram of a compressed moving image special effect device according to a second embodiment of the present invention.

[Explanation of symbols]

 1, 2 Compressed moving image input buffer 3, 4, 8, 11 Switch 5 Decoding means 6,7 Frame memory 9 Encoding means 10 Output buffer 12 Input means 13 Synthesis control means 14 Zero difference block signal generation means

Claims (3)

[Claims] 1. A frame image is divided into blocks of m × n (m and n are natural numbers) pixels, and each block is subjected to intra-frame coding or forward prediction code using a difference from a prediction block for a past frame. The frame images of the first and second input compressed moving images are sequentially synthesized with respect to the first and second compressed moving image signals that have been subjected to encoding based on a wipe pattern, and compression is performed with a wipe effect. A compressed moving image special effect device for outputting a moving image signal, comprising: a first input buffer for temporarily holding the first compressed moving image signal; and a second input buffer for temporarily holding the second compressed moving image signal. An input buffer; a decoding means for decoding the first or second compressed moving image signal held in the first or second input buffer into an uncompressed frame image signal; The first image A first frame memory that temporarily holds the signal in frame units, a second frame memory that temporarily holds the second image signal decoded by the decoding unit in frame units, and a second frame memory that stores the first image signal in second frames. When wiping with the image signal of, the wiping input means for inputting the wiping pattern and the wiping speed, and the wiping line included in the output block of the current frame,
And when the block of the previous frame corresponding to the output block of the current frame includes a wipe line, the first and second image signals corresponding to the output block are changed to the first and second image signals.
Encoding means for reading out from the frame memory, creating a composite block based on the wipe line of the wipe input means, and encoding the image signal of the composite block in the same system as the input compressed moving image signal; An output buffer for switching and temporarily holding the first or second compressed moving image signal held in the input buffer, and a wipe line of each successive frame when a wipe pattern and a wipe speed are input from the wipe input means. When a wipe line is included in the output block of the current frame and when a wipe line is included in the block of the previous frame corresponding to the output block of the current frame, the encoding is performed as the image signal of the output block. Output the image signal of the means, the output block of the current frame does not include the wipe line, the output block of the current frame When not included wipe lines in the corresponding block of the previous frame,
And a composite control means for outputting the image signal of the output buffer as the image signal of the output block. 2. From the start of the wipe to the end of the wipe, either one of the first and second compressed moving image signals is held as a still image, and a block signal indicating that there is no difference in the image signals between frames is generated. At the same time, a zero-difference block signal generating means for instructing the synthesis control means to switch to the zero-difference block signal and output the image signal of the output block is provided. Video special effect device. 3. A first compression method and a second compression method when each block of an input compressed video signal is subjected to intraframe coding, forward prediction coding, or bidirectional prediction coding. When the frames of the moving image signal are combined in the reproduction order from the start frame to the end frame of the wipe one by one in the reproduction order, when one compressed moving image signal includes a signal of backward predictive coding or bidirectional predictive coding, When the compressed moving picture signal includes backward prediction coding or bidirectional prediction coding, and when one of the compressed moving picture signals does not include either backward prediction coding or bidirectional prediction coding The synthesizing control means controls the input of the first or second input buffer so that the other compressed moving image signal does not include any signal of backward predictive coding and bidirectional predictive coding. Characteristic The compressed moving image special effect device according to claim 1 or 2.