JPH05336510A - Motion compensation encoding device and decoding device - Google Patents

Abstract

PURPOSE:To simplify a motion vector detecting means and saves the amount of codes for encoding a motion vector by generating a part of the motion vector by interpolation. CONSTITUTION:A motion detecting means 2 compares an input signal 1 with the decoded signal 12 of a previous screen outputted from a memory 11 to detect the motion vector 3. From the motion vector 3, a motion interpolative generating means 13 generates the motion vector 14 of an area which is not detected by the motion detecting means 2. A motion compensating and encoding means 4 compares the input signal 1 with the decoded signal 8 of the contents of a memory 11 corresponding to the motion vector 14 and encodes the difference when the difference is small, but encodes the input signal 1 as it is when not, thereby outputting the encoded signal 5. An encoded signal 6 is also outputted separately from the encoding signal 5 after error correction. A motion compensating and decoding means 7 performs decoding with a decoded signal 8 and the encoded signal 6 to generate a decoded signal 9. The decoded signal 9 is recorded in the memory 11 and used for the encoding and decoding of a next screen.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motion compensation coding apparatus and motion compensation decoding which is one of high efficiency coding techniques used for reducing the data amount of an image signal to be transmitted or recorded. It relates to the device.

[0002]

2. Description of the Related Art A block diagram of a conventional motion compensation coding apparatus is shown in FIG. In the figure, 1 is an image input signal, 2
Is a motion detecting means, 3 is a motion vector, 4 is motion compensation coding means, 5 and 6 are coded signals, 7 is motion compensation decoding means, 8 is a decoded signal of the previous screen, 9 is a decoded signal, 11 Is a memory, and 12 is a decoded signal of the previous screen.

The operation of the conventional motion compensation coding apparatus configured as described above will be described below. The motion detecting means 2 compares the input signal 1 and the decoded signal 12 of the previous screen output from the memory 11 to detect the motion vector 3. As a concrete means for detecting the motion, there is, for example, means for matching the input signal 1 and the decoded signal 12 of the previous screen and setting the relative position where the matching error is the minimum value as the motion vector. In the motion compensation coding means 4, the input signal 1 is compared with the decoded signal 8 which is the content of the memory 11 corresponding to the motion vector 3, and if the difference is small, the difference is coded,
Otherwise, the input signal 1 is encoded as it is, and the encoded signal 5 is output. It is to be noted that, when decoding, a coded signal that is compressed only by removing the transmission line and error correction is necessary, and is output as a coded signal 6. The motion compensation decoding means 7 decodes the decoded signal 8 and the coded signal 6 to generate a decoded signal 9. Decoded signal 9 is in memory 1
1 and is used for encoding and decoding of the next screen.

Next, a block diagram of a conventional motion compensation decoding apparatus is shown in FIG. In the figure, 21 is an encoded signal,
22 is a motion decoding means, 23 is a motion vector, 24 is a motion compensation decoding means, 25 is a decoded signal, 26 is a memory, 2
Reference numeral 8 is a decoded signal of the previous screen.

The operation of the conventional motion compensation decoding apparatus configured as described above will be described below. The motion decoding means 22 decodes the motion vector 23 from the encoded signal 21 and sends the motion vector 23 to the motion compensation decoding means 24. The motion compensation decoding means 24 decodes the coded signal 21 from the memory 26 using the decoded signal 28 of the previous screen corresponding to the motion vector 23. The decoded signal 25 is stored in the memory 26 and used for decoding the next screen.

[0006]

However, in the above-mentioned configuration, it is necessary to code the motion vector for each coding unit, and the code amount for coding the motion vector increases, and Efficiency decreases. Further, the motion vector detecting means requires a large-scale hardware, and the hardware scale can be reduced by reducing the number of times the motion vector is detected.

In view of such a point, the present invention reduces a motion vector required for encoding to reduce a hardware size, and a motion compensation encoding device which enhances encoding efficiency as compared with a conventional motion vector encoding method, and An object of the present invention is to provide a motion compensation decoding device that decodes a coded signal.

[0008]

In order to solve the above problems, a motion compensation coding apparatus of the present invention comprises a motion vector detecting means for detecting a motion vector from a current screen input signal and a previous screen decoded signal, and Utilizing a motion vector generating means for generating a motion vector at another position on the current screen from the motion vector detected by the motion vector detecting means, and a previous screen decoded signal corresponding to the motion vector generated by the motion vector generating means. Motion compensation encoding means for encoding the current screen input signal, and motion for decoding the signal encoded by the motion compensation encoding means using the previous screen decoded signal used in the motion compensation encoding means. It comprises a compensation decoding means and a memory for storing the signal decoded by the motion compensation decoding means for use in the next screen.

Further, the motion compensation coding apparatus of the present invention comprises a motion vector detecting means for detecting a motion vector from the current screen input signal and the previous screen decoded signal, and another position of the current screen from the coded motion vector. Motion vector generating means for generating the motion vector of the current screen, and a motion for encoding the current screen input signal by using the previous screen decoded signal corresponding to the motion vector generated by the motion vector detecting means and the motion vector generating means. Compensation coding means, motion compensation decoding means for decoding the signal coded by the motion compensation coding means using the previous screen decoded signal used in the motion compensation coding means, and the motion compensation decoding It is composed of a memory for storing the signal decoded by the converting means for use in the next screen.

Also, the motion compensation decoding apparatus of the present invention comprises motion decoding means for decoding a motion vector from a coded signal, motion compensation from the coded signal, the motion decoding means, and the previous screen decoded signal. The data is decoded and stored in the memory, and comprises motion compensation decoding means.

[0011]

In the first motion compensation coding apparatus of the present invention, the motion detection means compares the input signal of the current screen with the decoded signal of the previous screen read from the memory to detect the motion vector. This motion detection is performed on a partial area within the screen. The motion interpolation generation means generates a motion vector by interpolation from a motion vector at a position near a region where motion vector detection is not performed. If the motion vector detected by the motion vector detecting means is encoded,
The motion vector generated by the motion interpolation generating means can also be generated from the nearby motion vector in the motion compensation decoding device as well. Therefore, only the motion vector detected by the motion vector detecting means needs to be encoded as additional information. After the motion vectors for all areas are generated in this way, the motion compensation coding means performs motion compensation coding. The coded signal is decoded by the motion compensation coding means, recorded in the memory and used as a decoded signal for the next screen.

In the second motion compensation coding apparatus of the present invention, the difference from the first invention is that the motion vector is generated by interpolation from the motion vector decoded by the motion interpolation generating means. As a result, the motion vector interpolation generating means becomes more complicated than that of the first invention, but since only the decoded motion vector is used, it is necessary to judge whether or not the motion vector necessary for interpolation is coded. Absent.

In the motion compensation decoding means of the present invention, the motion decoding means decodes the motion vector from the coded signal, and the motion interpolation generation means interpolates and generates the motion vector of the uncoded area. The motion compensation decoding means performs decoding using the coded signal, the motion vector generated by the motion interpolation generation means, and the decoded signal of the previous screen read from the memory.

The motion vector has a strong correlation between adjacent regions, and even if the motion vector is interpolated and generated as described above,
There is almost no difference from the motion vector detected by the direct motion detection means, and as a result, the coding efficiency of the motion-compensated signal does not deteriorate. Therefore, as described above, the motion compensation coding and the motion compensation decoding can be performed without coding the motion vectors of all the regions, and the motion vector can be calculated more than the conventional motion compensation coding apparatus and the motion compensation decoding apparatus. It is possible to reduce the amount of additional information required for encoding and reduce the amount of calculation required for motion vector detection.

[0015]

1 is a block diagram of a motion compensation coding apparatus according to a first embodiment of the present invention. In the figure, 1 is an image input signal, 2 is a motion detecting means, 3 is a motion vector,
13 is a motion interpolation generating means, 14 is a motion vector, 4 is motion compensation coding means, 5 and 6 are coded signals, 7 is motion compensation decoding means, 8 is a decoded signal of the previous screen, and 9 is a decoded signal. , 11 is a memory, and 12 is a decoded signal of the previous screen.

The operation of the conventional motion compensation coding apparatus configured as described above will be described below. The motion detecting means 2 compares the input signal 1 and the decoded signal 12 of the previous screen output from the memory 11 to detect the motion vector 3. Motion vector detection area (usually rectangular block)
Although it is performed in units, this motion vector detection is performed in some areas, not in all areas. Therefore, the number of calculations is significantly reduced as compared with the case where motion vectors are detected for all areas. From the motion vector 3, the motion interpolation generating means 13 generates the motion vector 14 of the area which is not detected by the previous motion detecting means 2. The motion detection means 2
The motion vector 3 detected in 3 is also included in the motion vector 14. For example, it is assumed that the motion detecting means 2 detects the motion vectors Vi and Vi + 3 as shown in FIG. The motion interpolation generating means 13 generates motion vectors Vi + 1 and Vi + 2 by interpolation from the motion vectors Vi and Vi + 3, and outputs the motion vectors Vi, Vi + 1, Vi + 2 and Vi + 3 as the motion vector 14. In the image signal, the motion vectors of adjacent regions have a strong correlation, and even if the motion vector is generated by interpolation in this way, the difference from the motion vector detected directly is small, and the coding efficiency of the motion compensation signal is almost degraded. do not do. In the motion compensation coding means 4, the input signal 1 is compared with the decoded signal 8 which is the content of the memory 11 corresponding to the motion vector 14, and if the difference is small, the difference is coded, otherwise the input signal 1 is left as it is. Encode and output the encoded signal 5. At this time, the motion vector 14 is encoded as additional information. However, the motion vector 14 other than the motion vector 3 can be interpolated and generated in the motion compensation decoding device, and therefore the additional information of the motion vector encoding is conventionally used. It can be significantly reduced compared to the example. Note that a coded signal is required for motion compensation decoding, and a coded signal 6 is also output in addition to the coded signal 5 that has undergone error correction. The motion compensation decoding means 7 decodes the decoded signal 8 and the coded signal 6 to generate a decoded signal 9. The decoded signal 9 is recorded in the memory 11 and used for encoding and decoding the next screen.

As described above, according to the present embodiment, by adding the motion interpolation generating means to the conventional motion compensation coding apparatus, the number of calculations of the motion detecting means 2 is reduced and the motion vector is further coded. It is possible to reduce the amount of additional information required for this.

FIG. 3 is a block diagram of a motion compensation coding apparatus according to the first embodiment of the present invention. In the figure, 1 is an image input signal, 2 is motion detection means, 3 is motion vector, 13 is motion interpolation generation means, 14 is motion vector, 4
Is a motion compensation coding means, 5, 6, 15 are coded signals, 7
Is a motion compensation decoding means, 8 is a decoded signal of the previous screen, 9 is a decoded signal, 11 is a memory, and 12 is a decoded signal of the previous screen.

The operation of the second embodiment of the present invention constructed as above will be described below. 3 is almost the same as FIG. 1, and the operation of the motion interpolation generating means 13 is different from that of the embodiment of FIG. In the embodiment of FIG. 1, the motion vector is interpolated and generated from the motion vector 3. However, the motion vector 3 needs to be encoded in order for the motion compensation decoding apparatus to correctly interpolate the motion vector. In the motion compensation coding means 4 of the embodiment shown in FIG. 2, the area in which the motion vector 3 is detected is coded. At this time, only the motion vector 3 corresponding to the area in which the motion is compensated is coded by the additional information. Turned into
The motion vector of the area that is not motion-compensated (intra-picture encoded) is not encoded. Therefore, the motion vector of the area that is not motion-compensated cannot be used by the motion interpolation generating means 13. Therefore, in this embodiment, the coded signal 15 obtained by coding the motion vector is decoded, and the motion vector 14 is interpolated and generated from the coded motion vector. An example of the interpolation is shown in FIG. In FIG. 4, reference numeral 15 is a coded signal, 51a is an average interpolation means, 51b is a forward interpolation means, 51c is a backward interpolation means, 52a, 52b and 52c are motion vectors, 53 is a selector, and 14 is a motion vector. The average interpolation means 51a decodes a motion vector from the encoded signal 15, and interpolates and generates a motion vector 52a at a position between the decoded motion vectors before and after. The front interpolation means 51b decodes the motion vector from the coded signal 15, and interpolates and generates the motion vector 52b at the previous position from the decoded motion vector at the rear position. The backward interpolation means 51c decodes a motion vector from the encoded signal 15, and interpolates and generates a motion vector 52c at a subsequent position from the decoded motion vector at the previous position. The selector 53 uses the interpolation-generated motion vectors 52a and 52a.
One is selected from b and 52c based on a predetermined reference and is output as the motion vector 14. The selection criteria include, for example: backward interpolation means if only the motion vector at the immediately preceding position has been decoded, forward interpolation means if only the motion vector at the immediately succeeding position has been decoded, Should be switched to the mean interpolation means.

As described above, according to this embodiment, by adding the motion interpolation generating means to the conventional motion compensation coding apparatus, the number of calculations of the motion detecting means 2 is reduced and the motion vector is further coded. It is possible to reduce the amount of additional information required for this. Further, unlike the first embodiment, since the motion vector 14 is generated by interpolation from only the decoded motion vector, it is not necessary to code all the motion vectors 3.

FIG. 5 is a block diagram of a motion compensation decoding apparatus according to the third embodiment of the present invention. In the figure, 21
Is a coded signal, 22 is a motion decoding means, 23 is a motion vector, 30 is a motion interpolation generating means, 31 is a motion vector, 2
4 is a motion compensation decoding means, 25 is a decoded signal, 26 is a memory, and 28 is a decoded signal of the previous screen.

The operation of the conventional motion compensation decoding apparatus configured as described above will be described below. The motion decoding means 22 decodes the motion vector 23 from the encoded signal 21 and sends the motion vector 23 to the motion interpolation generating means 30. The motion interpolation generation means 30 outputs the motion vector 23 as the motion vector 31 when the motion vector 23 at that position exists, and when not present, generates the motion vector 31 from the motion vector 23 by interpolation. The motion compensation decoding means 24 uses the decoded signal 28 of the previous screen corresponding to the motion vector 31 from the memory 26 to generate the encoded signal 2.
Decode 1 The decoded signal 25 is stored in the memory 26 and used for decoding the next screen.

As described above, according to the present embodiment, the motion interpolation generating means 30 is installed between the motion decoding means 22 and the motion compensation decoding means 24, so that the motion compensation coding means of the present invention performs coding. The encoded signal can be successfully decoded.

[0024]

As described above, according to the present invention, the amount of calculation required for motion vector detection can be reduced and the amount of additional information required for coding a motion vector can be reduced. The effect is great.

In FIG. 4, average interpolation, forward interpolation and backward interpolation are selected as one interpolation method in FIG. 4, but only a part of these three methods is used or another interpolation method is used. May be.

[Brief description of drawings]

FIG. 1 is a block diagram of a motion compensation coding apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of motion vector interpolation.

FIG. 3 is a block diagram of a motion compensation coding apparatus according to a second embodiment of the present invention.

FIG. 4 is an explanatory diagram of motion vector interpolation.

FIG. 5 is a block diagram of a motion compensation decoding apparatus that is a third embodiment of the present invention.

FIG. 6 is a block diagram of a conventional motion compensation encoding device.

FIG. 7 is a block diagram of a conventional motion compensation decoding device.

[Description of Codes] 2 motion detection means 4 motion compensation coding means 7 motion compensation decoding means 11, 26 memory 13, 30 motion interpolation generation means 22 motion decoding means 24 motion compensation decoding means

Claims (3)

[Claims] 1. A motion vector detecting means for detecting a motion vector from a current screen input signal and a previous screen decoded signal, and a motion vector at another position of the current screen from the motion vector detected by the motion vector detecting means. Motion vector generation means, motion compensation coding means for coding the current screen input signal using the previous screen decoded signal corresponding to the motion vector generated by the motion vector generation means, and the motion compensation coding means The motion compensation decoding means for decoding the signal encoded by the motion compensation encoding means using the previous screen decoded signal used in the above, and the signal decoded by the motion compensation decoding means on the next screen. A motion compensation coder comprising a memory for storing for use. 2. A motion vector detecting means for detecting a motion vector from a current screen input signal and a previous screen decoded signal, and a motion vector generating means for generating a motion vector at another position of the current screen from the encoded motion vector. A motion compensation coding means for coding a current screen input signal using a previous screen decoded signal corresponding to the motion vector generated by the motion vector detection means and the motion vector generation means; and the motion compensation code. Next, a motion compensation decoding means for decoding the signal encoded by the motion compensation encoding means using the front screen decoded signal used by the encoding means, and a signal decoded by the motion compensation decoding means are A motion compensation coding device consisting of a memory that stores for use on a screen. 3. A motion decoding means for decoding a motion vector from a coded signal, a motion compensation decoding from the coded signal, the motion decoding means, and a previous screen decoded signal, which is stored in the memory and motion compensated. A motion-compensated decoding device comprising decoding means.