JP2018026726A - Encoder and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To select efficiently whether or not a time prediction motion vector candidate is used as a candidate of prediction motion vector.SOLUTION: An encoder 1 includes a frame interval acquisition unit 11 for finding the minimum frame interval of a coding object frame and a frame subjected to motion compensative prediction, out of reference frames referred when the coding object frame is encoded, a time prediction motion vector candidate determination unit 12 for determining whether or not a time prediction motion vector candidate is used as a candidate of prediction motion vector, according to the minimum frame interval, and a coding unit 20 for encoding a coding object frame, according to determination results by the time prediction motion vector candidate determination unit 12.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an encoding apparatus that performs adaptive motion vector predictive encoding.

  In recent years, video with a high frame rate such as a frame frequency of 120 Hz (120 frames per second) or 240 Hz (240 frames per second) is becoming widespread. High frame rate video is characterized by the ability to smoothly display fast-moving subjects and is suitable for sports content. In the future, broadcasting using 120 Hz video is being studied, and compression encoding technology has become an issue for its realization. In order to encode a 120 Hz video in real time, it is necessary to process one frame in half the time of a conventional 60 Hz video.

  H.264, which is a video encoding method adopted in the 8K / 4K broadcasting standard. In H.265 / HEVC (High Efficiency Video Coding), H.264 of the conventional method is used. Similarly to H.264 / AVC (Advanced Video Coding), inter prediction that predicts the pixel value of a portion to be encoded from a neighboring frame is employed. H. The inter prediction of H.265 / HEVC is H.264. Similar to H.264 / AVC, prediction can be performed using a frame selected from a plurality of reference frame candidates. Non-Patent Document 1 describes H.264 in 120 Hz broadcasting. H.265 / HEVC GOP (Group Of Picture) structure is described. FIG. 6 shows an example of a GOP structure consisting of 16 frames.

  In FIG. 6, the numbers in the rectangles indicate frame numbers, and the same GOP structure is assumed for frame numbers 17 and later. The underlined numbers in the figure indicate the order of encoding / decoding processing, and the frames are rearranged in the order of frame numbers 0, 16, 1, 8, 3, 4, 5, 2, 7, 6. . After the decoding process, the frames are rearranged so as to be displayed on the monitor in order from frame number 0. Moreover, the arrow in a figure shows a reference frame. For example, the frame with frame number 16 is predicted with reference to the encoded image with frame number 0, and the frame with frame number 1 is predicted with reference to the encoded images with frame numbers 0 and 16. In the GOP structure of FIG. 6, by using a structure in which even-numbered frames are referred to, temporal hierarchical coding is realized by decoding only even-numbered frames and generating 60 Hz video. As a result, even if 120-Hz broadcasting is started in the future, the conventional receiver can reproduce 60-Hz video. Here, the frame corresponding to the difference between the 60 Hz video and the 120 Hz video (the odd-numbered frame in FIG. 6) is referred to as the highest time hierarchy.

  H. In the inter prediction of H.265 / HEVC, H.264 is used. Similar to H.264 / AVC, motion compensation prediction is used in which a motion vector indicating a motion amount from a reference frame is detected and predicted. Non-Patent Document 2 describes H.C. A motion vector prediction method of H.265 / HEVC is described. In order to reduce the amount of code of the motion vector to be transmitted, a prediction motion vector having a smaller difference vector from the actual motion vector is selected from prediction motion vector candidates derived from the motion vectors of adjacent encoded blocks. The index indicating the difference vector and the predicted motion vector is transmitted to the decoding side. Such an encoding method is called adaptive motion vector predictive encoding.

  FIG. 265 / HEVC predicted motion vector candidate types. FIG. 7A shows spatial prediction motion vector candidates, and FIG. 7B shows temporal prediction motion vector candidates. H. In H.265 / HEVC, motion vector information is accurately and efficiently encoded by selecting a maximum of two motion vector predictor candidates in the priority order of a spatial motion vector candidate, a temporal motion vector predictor candidate, and a zero motion vector predictor candidate. Can be

  In the spatial motion vector predictor candidate, a block near the prediction unit (PU: Prediction Unit) P1 to be encoded is a motion vector candidate. Specifically, the motion vectors of the blocks A0, A1 adjacent to the lower left side of P1 and the blocks B0, B1, B2 adjacent to the upper side of P1 are candidates. In the temporal prediction motion vector candidate, a motion vector of a block near the same spatial position as the prediction unit P1 to be encoded in the reference frame is a candidate. Specifically, the motion vectors of the block H adjacent to the lower right of the block P2 at the same spatial position as P1 in the reference frame and the block C3 at the lower right of the center of the block P2 are candidates. In the zero prediction motion vector candidate, the motion vector (0, 0) is set as a candidate.

ARIB STD-B32 version 3.6, “Video coding, audio coding and multiplexing methods in digital broadcasting”, revised on March 25, 2016 Supervised by Satoshi Okubo, “Impress Standard Textbook Series H.265 / HEVC Textbook”, Impress Japan Co., Ltd., October 21, 2013

  H. In H.265 / HEVC, a prediction motion vector can be selected from a large number of candidates, but there is a problem that selection takes time. In addition, since the temporal motion vector predictor candidate needs to refer to another frame and is easily affected by a transmission error, use / non-use can be selected by the syntax SPS (Sequence Parameter Set). Table 1 shows the results of an encoding experiment using three types of 2K (spatial resolution 1920 × 1080) / 120 Hz images. In this experiment, the GOP structure shown in FIG. 6 is used, and a temporal motion vector predictor based on a case where a temporal motion vector prediction (TMVP) is used as a prediction motion vector candidate in all frames. The code amount increase rate when not used was obtained.

  As shown in Table 1, when the temporal motion vector is not used, there is a problem that the code amount increases by about 2% at the maximum, and the influence on the coding efficiency becomes large.

  An object of the present invention made in view of such circumstances is to provide an encoding device and a program capable of efficiently selecting whether or not a temporal motion vector predictor is a motion vector predictor candidate.

  In order to solve the above-described problem, an encoding apparatus according to the present invention is an encoding apparatus that selects a prediction motion vector in which a difference vector from a motion vector is small from prediction motion vector candidates, and includes: A frame interval obtaining unit for obtaining a minimum frame interval with a frame subjected to motion compensation prediction among reference frames that the encoding target frame refers to when encoding, and a temporal prediction motion vector according to the minimum frame interval A temporal motion vector predictor candidate determination unit that determines whether or not to use a candidate as a motion vector predictor candidate, and an encoding unit that encodes the encoding target frame according to a determination result by the temporal motion vector predictor candidate determination unit And.

  Furthermore, the encoding apparatus according to the present invention further includes a frame motion determination unit that determines whether or not the encoding target frame is a fixed-captured video, and the temporal prediction motion vector candidate determination unit includes the frame When the motion determination unit determines that the encoding target frame is a fixed-captured video, it determines that a temporal prediction motion vector is not used as a predicted motion vector candidate, and the frame motion determination unit determines the code. And determining whether to use a temporal motion vector predictor candidate as a motion vector predictor candidate according to the minimum frame interval when it is determined that the target frame is not a fixed-captured video. To do.

  Furthermore, in the encoding device according to the present invention, the frame motion determination unit determines whether or not the encoding target frame is a fixed-captured video in GOP units.

  In order to solve the above problems, a program according to the present invention causes a computer to function as the encoding device.

  According to the present invention, it is possible to efficiently select whether or not to use a temporal motion vector predictor as a motion vector predictor candidate, and to narrow down motion vector predictor candidates. Therefore, the calculation time can be shortened by reducing the calculation amount of the encoding process while keeping the encoding efficiency from decreasing.

It is a block diagram which shows the structural example of the encoding apparatus which concerns on the 1st Embodiment of this invention. It is a flowchart which shows the operation example of the encoding apparatus which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the structural example of the encoding part in the encoding apparatus which concerns on the 1st Embodiment of this invention. It is a block diagram which shows the structural example of the encoding apparatus which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows the operation example of the encoding apparatus which concerns on the 2nd Embodiment of this invention. It is a figure which shows the example of the GOP structure which consists of 16 frames. H. It is a figure which shows the kind of prediction motion vector candidate of H.265 / HEVC.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
An encoding apparatus according to the first embodiment of the present invention will be described below. FIG. 1 shows a configuration example of an encoding apparatus according to the first embodiment. The encoding device 1 illustrated in FIG. 1 includes a frame interval acquisition unit 11, a temporal prediction motion vector candidate determination unit 12, and an encoding unit 20.

  The encoding device 1 selects a predicted motion vector that has a smaller difference vector from the motion vector from among the predicted motion vector candidates, and performs adaptive motion vector predictive encoding.

  The frame interval acquisition unit 11 inputs frame information including the frame number of the encoding target frame. The frame interval acquisition unit 11 stores in advance the frame numbers of one or more reference frames that the encoding target frame refers to when encoding, in association with the frame numbers of the encoding target frames. Then, the frame interval acquisition unit 11 obtains the minimum frame interval between the encoding target frame and the non-I frame on which the motion compensation prediction has been performed among the reference frames to which the encoding target frame refers during encoding. It outputs to the prediction motion vector candidate determination part 12.

  In this specification, description will be made assuming that the GOP structure shown in FIG. 6 is used. In this case, the same structure as that of frame numbers 1 to 16 is repeated after frame number 17, and I-frames (frames composed only of I slices) in which motion compensation prediction is not performed on the portion of frame number 0 at a predetermined interval. Is inserted. Table 2 shows the relationship of the minimum frame interval m between the encoding target frame and the non-I frame reference frame. In addition, it indicates whether or not m = 1 and whether or not m ≦ 2.

  A supplementary description will be given of the case where the frame number of the encoding target frame is 1 and the frame numbers of the reference frames are 0 and 16. When the frame having the frame number 0 is a non-I frame, the minimum frame interval m is 1-0 = 1. However, when the frame whose frame number is 0 is an I frame, the minimum frame interval m between the encoding target frame and the non-I frame reference frame is 16-1 = 15. Therefore, in Table 2, “◯ or ×” is written.

  Temporal motion vector predictor candidates are derived from a block P2 at the same spatial position as the prediction unit P1 to be encoded in the reference frame or a block near the block P2. When the time interval with the reference frame is large, it is unlikely that there is a motion similar to the prediction unit P1 in the vicinity of the block P2, and therefore the temporal prediction motion vector candidate has a frame interval between the encoding target and the reference frame. When it is small, it is considered that it is easy to be selected as a predicted motion vector.

  Therefore, the temporal motion vector predictor candidate determination unit 12 determines whether to use the temporal motion vector predictor candidate as a motion vector predictor candidate according to the minimum frame interval m input from the frame interval acquisition unit 11. Specifically, the temporal prediction motion vector candidate determination unit 12 determines that the temporal prediction motion vector candidate is used as a prediction motion vector candidate when the minimum frame interval m is equal to or less than the threshold k, and the minimum frame interval m is When it is larger than the threshold value k, it is determined that the temporal motion vector predictor candidate is not used as a motion vector predictor candidate, and TMVP determination information indicating the determination result is output to the encoding unit 20.

  The encoding unit 20 encodes the encoding target frame according to the determination result of the temporal prediction motion vector candidate determination unit 12 and outputs the encoded data to the outside of the encoding device 1.

  Next, the operation of the encoding apparatus 1 will be described with reference to FIG. FIG. 2 is a flowchart showing an operation example of the encoding apparatus 1.

  In step S11, the frame interval acquisition unit 11 obtains the minimum frame interval m between the encoding target frame and the non-I frame reference frame, and the process proceeds to step S12.

  In step S12, the temporal motion vector predictor candidate determination unit 12 determines whether or not the minimum frame interval m is equal to or less than the threshold value k. If the minimum frame interval m is less than or equal to the threshold value k, the process proceeds to step S13. If the minimum frame interval m is greater than the threshold value k, the process proceeds to step S14. Here, the threshold value k may be 1. Further, since the time interval between adjacent frames is short in the high frame rate video, the threshold value k may be determined so that step S12 becomes Yes when the minimum frame interval is within 1/50 second, for example. In the case of 1/50 seconds or less, the threshold k = 2 for 120 Hz video and the threshold k = 4 for 240 Hz video.

  In step S13, the encoding unit 20 encodes the encoding target frame using temporal prediction motion vector candidates for motion vector prediction, and the process proceeds to step S15.

  In step S14, the encoding unit 20 encodes the encoding target frame without using the temporal prediction motion vector candidate for the motion vector prediction, and the process proceeds to step S15.

  In step S15, it is determined whether the encoding target frame is the last frame. If it is the last frame, the process ends. If not, the process returns to step S11 to repeat the process.

  Next, the configuration of the encoding unit 20 will be described with reference to FIG. FIG. 3 is a block diagram illustrating a configuration example of the encoding unit 20. 3 includes a block dividing unit 21, a subtracting unit 22, a transforming unit 23, a quantizing unit 24, an inverse quantizing unit 25, an inverse transforming unit 26, an adding unit 27, A storage unit 28, an intra prediction unit 29, a motion compensation prediction unit 30, a switching unit 31, an entropy encoding unit 32, and a loop filter unit 33 are provided.

  The block division unit 21 divides the encoding target frame into a plurality of blocks, and outputs the block image to the subtraction unit 22, the intra prediction unit 29, and the motion compensation prediction unit 30. The block size may be variable, for example, 32 × 32 pixels, 16 × 16 pixels, 8 × 8 pixels, or 4 × 4 pixels.

  The subtraction unit 22 subtracts each pixel value of the prediction block image input from the intra prediction unit 29 or the motion compensation prediction unit 30 described later from each pixel value of the block image input from the block division unit 21, A residual block image indicating the difference between the image and the predicted block image is generated and output to the conversion unit 23.

  The transform unit 23 performs transform processing such as orthogonal transform on the residual block image input from the subtracting unit 22 to calculate a transform coefficient that has been two-dimensionally transformed, and the transform coefficient for each block is quantized by the quantization unit 24. Output to.

  The quantization unit 24 divides the transform coefficient for each block input from the transform unit 23 by the quantization step and quantizes it to generate a quantized coefficient, which is sent to the inverse quantization unit 25 and the entropy coding unit 32. Output.

  The inverse quantization unit 25 restores the transform coefficient for each block by multiplying the quantization coefficient input from the quantization unit 24 by a quantization step, and outputs it to the inverse transform unit 26.

  The inverse transform unit 26 performs inverse transform of the transform performed by the transform unit 23 on the transform coefficient input from the inverse quantization unit 25 to restore the residual block image, and outputs the residual block image to the adder 27. For example, when the transform unit 23 performs discrete cosine transform, the inverse transform unit 26 performs inverse discrete cosine transform.

  The adding unit 27 adds the residual block image input from the inverse transform unit 26 and each pixel value of the predicted block image input from the motion compensation prediction unit 30 and outputs the result to the loop filter unit 33.

  The loop filter unit 33 performs filter processing on the image output from the adding unit 27 and outputs the result to the storage unit 28 as a decoded block image.

  The storage unit 28 is a memory that stores the decoded block image input from the loop filter unit 33.

  The intra prediction unit 29 performs intra prediction with reference to the decoded block image stored in the storage unit 28 to generate an intra prediction image, and outputs the intra prediction image to the switching unit 31. Further, the selected intra prediction mode is output to the entropy encoding unit 32.

  The motion compensation prediction unit 30 refers to the decoded block image stored in the storage unit 28 and generates a motion vector by a technique such as block matching. If the TMVP determination information input from the temporal prediction motion vector candidate determination unit 12 indicates that the temporal prediction motion vector candidate is not used, the temporal prediction motion vector candidate is not used and the spatial prediction motion vector candidate is used. , And zero predicted motion vector candidates, and outputs an index indicating the predicted motion vector and a difference vector from the motion vector to the entropy encoding unit 32. On the other hand, when the TMVP determination information indicates that the temporal motion vector predictor candidate is used, a motion vector predictor is selected from the spatial motion vector predictor candidate, the temporal motion vector predictor candidate, and the zero motion vector predictor candidate. The index indicating the predicted motion vector and the difference vector from the motion vector are output to the entropy coding unit 32.

  In addition, the motion compensation prediction unit 30 generates a motion compensated prediction image based on the motion vector and outputs the motion compensation prediction image to the switching unit 31.

  The switching unit 31 switches between the intra prediction image input from the intra prediction unit 29 and the motion compensated prediction image input from the motion compensation prediction unit 30, and outputs the result to the subtraction unit 22 and the addition unit 27.

  The entropy encoding unit 32 includes a quantization coefficient input from the quantization unit 24, an intra prediction mode input from the intra prediction unit 29, an index and a difference vector indicating the prediction motion vector input from the motion compensated prediction unit 30, And the entropy encoding is performed on the information about the filter input from the loop filter unit 33, the data compression is performed, the bit stream is generated, and output to the outside of the encoding device 1. For entropy coding, any entropy coding scheme such as 0th-order exponent Golomb code or CABAC (Context-based Adaptive Binary Arithmetic Coding) can be used.

  Note that a computer can be suitably used to cause the above-described encoding device 1 to function, and such a computer stores a program describing processing contents for realizing each function of the encoding device 1 in the storage unit of the computer. This program can be realized by reading out and executing this program by the CPU of the computer. This program can be recorded on a computer-readable recording medium.

  Thus, the encoding apparatus 1 and the program thereof obtain the minimum frame interval m between the encoding target frame and the non-I frame that the encoding target frame refers to when encoding, and the minimum frame interval m is equal to or less than the threshold value k. Is used as a motion vector predictor candidate, and when the minimum frame interval m is larger than the threshold k, the motion vector predictor candidate is not used as a motion vector predictor candidate. . Therefore, the encoding apparatus 1 can appropriately narrow down the prediction motion vector candidates, and can reduce the amount of encoding processing and reduce the calculation time while keeping down the encoding efficiency.

  The experimental results are shown below. Table 3 shows results of experiments using three types of 2K 120 Hz images similar to those in Table 1, assuming that the threshold k = 1, that is, the temporal motion vector predictor candidate is used only when the minimum frame interval m = 1. It is a table | surface which shows. In addition, the code amount increase rate when the temporal motion vector predictor (TMVP) is not used as a motion vector predictor candidate in all frames is also shown.

  In this experiment, the I frame was inserted once in 64 frames, that is, once in 4 times of 16 GOP structures. For this reason, temporal prediction motion vector candidates are not used in more than half (9.25 / 16) frames, and the amount of coding processing is reduced while encoding is not performed compared to the case where temporal prediction motion vector candidates are not used. The increase in the amount can be suppressed. The encoding operation time can be shortened by about 2 to 3% compared to the case where temporal prediction motion vector candidates are used in all frames.

  Table 4 is a table showing the results of experiments performed in the same manner assuming that the threshold k = 2, that is, the temporal motion vector predictor candidate is used when the minimum frame interval m ≦ 2. In addition, the code amount increase rate when the temporal motion vector predictor (TMVP) is not used as a motion vector predictor candidate in all frames is also shown.

  In this case, the temporal motion vector predictor candidate is not used in about 40% (6.25 / 16) frames, and the temporal prediction motion vector candidate is not used while reducing the amount of calculation processing. Compared to this, the increase in the amount of codes can be greatly suppressed. The encoding operation time can be reduced by about 1 to 2% compared to the case where temporal prediction motion vector candidates are used in all frames.

(Second Embodiment)
Next, an encoding apparatus according to the second embodiment will be described. As shown in Tables 3 and 4, in the image A used in the experiment, the code amount increase rate when TMVP is not used is as low as 0.57%. Since the image A is a fixed-captured image, it can be considered that motion vector prediction is hardly used and it is sufficient to use spatial prediction vector candidates. Therefore, in this embodiment, first, after determining whether or not the encoding target frame is a fixed-captured video, it is determined whether or not to use a temporal motion vector predictor candidate.

  FIG. 4 shows a configuration example of an encoding apparatus according to the second embodiment. The encoding device 2 illustrated in FIG. 4 includes a frame interval acquisition unit 11, a temporal motion vector predictor determination unit 12, a frame motion determination unit 13, and an encoding unit 20. The encoding device 2 according to the second embodiment is different from the encoding device 1 according to the first embodiment in that it further includes a frame motion determination unit 13. Since other configurations are the same as those in the first embodiment, the same reference numerals are given and description thereof is omitted as appropriate.

はフレームｆ_ｉの輝度値の相加平均を表す。 The frame motion determination unit 13 determines whether or not the encoding target frame is a fixed-captured video, and outputs motion determination information indicating the determination result to the temporal prediction motion vector candidate determination unit 12. The determination as to whether or not the video is fixedly taken can be made based on, for example, whether or not the correlation coefficient of the luminance values of consecutive frames is 0.99 or more. A frame _{f 1} to be coded, the correlation coefficient r of the frame _{f 2} continuous in _{f 1} is obtained by Equation (1). In the formula _{(1), f i (x} , y) represents a luminance value at the coordinates of the frame _{f i,}

Represents the arithmetic mean of the luminance values of the frame f _i.

  Note that the determination method by the frame motion determination unit 13 is not limited to this. For example, the determination may be made based on whether or not the absolute difference value of the luminance values of consecutive frames is equal to or less than a threshold value.

  As in the first embodiment, the frame interval acquisition unit 11 is the minimum frame between the encoding target frame and a non-I frame on which motion compensation prediction has been performed among the reference frames that the encoding target frame refers to when encoding. The interval is obtained and output to the temporal prediction motion vector candidate determination unit 12.

  The temporal motion vector predictor candidate determination unit 12 must use the temporal motion vector predictor candidate as a motion vector predictor candidate when the frame motion determination unit 13 determines that the encoding target frame is a fixed-captured video. judge. In addition, when the frame motion determination unit 13 determines that the encoding target frame is not a fixed-captured video, if the minimum frame interval m is equal to or less than the threshold k, the temporal motion vector predictor candidate is selected as the motion vector predictor. When the minimum frame interval m is larger than the threshold k, it is determined that the temporal motion vector predictor candidate is not used as a motion vector predictor candidate.

  Next, the operation of the encoding device 2 will be described with reference to FIG. FIG. 5 is a flowchart illustrating an operation example of the encoding device 2.

  In step S21, the frame motion determination unit 13 determines whether or not the encoding target frame is a fixed-captured video. If it is determined that the shooting is fixed, the process proceeds to S24 and the temporal motion vector predictor candidate is not used. If it is determined that the shooting is not fixed, the process proceeds to step S22 to obtain the minimum frame interval m. Since the process of step S22-26 is the same as that of step S11-15 of Embodiment 1, description is abbreviate | omitted.

  In this embodiment, the determination in step S21 is performed in units of frames. However, it may be determined in units of GOPs whether or not the encoding target frame is a fixed-captured video. In this case, if it is determined that the first frame of the GOP is a fixed-captured video, all the frames in the GOP are considered to be fixed-captured, and the temporal motion vector predictor candidate is not used. To do.

  In addition, a computer can be suitably used for causing the above-described encoding device 2 to function, and such a computer stores a program describing processing contents for realizing each function of the encoding device 2 in the storage unit of the computer. This program can be realized by reading out and executing this program by the CPU of the computer. This program can be recorded on a computer-readable recording medium.

  As described above, the encoding device 2 and the program thereof determine whether or not the encoding target frame is a fixed-captured video. If the encoding target frame is a fixed-captured video, the time prediction is performed. The motion vector is not used as a predicted motion vector candidate. That is, since the encoding apparatus 2 considers whether or not the video is fixedly shot, it can further narrow down video prediction motion vector candidates. Compared with the encoding device 1, the encoding processing time can be further shortened when encoding a video including a frame that has been captured in a fixed manner.

  In the first and second embodiments described above, it is determined whether or not the temporal motion vector predictor candidate is used only for the frame in the highest temporal layer of the GOP structure (the odd-numbered frame in FIG. 6). However, it may always be used in other frames. In this case, compared with the above-mentioned embodiment, although the calculation time of an encoding process increases, encoding efficiency can be improved.

  Although the above embodiment has been described as a representative example, it will be apparent to those skilled in the art that many changes and substitutions can be made within the spirit and scope of the invention. Therefore, the present invention should not be construed as being limited by the above-described embodiments, and various modifications and changes can be made without departing from the scope of the claims. For example, it is possible to combine a plurality of constituent blocks described in the configuration diagram of the embodiment into one, or to divide one constituent block.

DESCRIPTION OF SYMBOLS 1, 2 Encoding apparatus 11 Frame space | interval acquisition part 12 Temporal prediction motion vector candidate determination part 13 Frame motion / static determination part 20 Encoding part 21 Block division part 22 Subtraction part 23 Conversion part 24 Quantization part 25 Inverse quantization part 26 Inverse conversion Unit 27 addition unit 28 storage unit 29 intra prediction unit 30 motion compensation prediction unit 31 switching unit 32 entropy coding unit

Claims (4)

An encoding device that selects a prediction motion vector that reduces a difference vector from a motion vector from prediction motion vector candidates,
A frame interval obtaining unit that obtains a minimum frame interval between a frame to be encoded and a frame in which motion compensation prediction has been performed among reference frames that the frame to be encoded refers to when encoding;
A temporal motion vector predictor candidate determination unit that determines whether or not to use a temporal motion vector predictor candidate as a motion vector predictor candidate according to the minimum frame interval;
An encoding unit that encodes the encoding target frame according to a determination result by the temporal prediction motion vector candidate determination unit;
An encoding device comprising: A frame motion determination unit that determines whether or not the encoding target frame is a fixed-captured video;
The temporal prediction motion vector candidate determination unit does not use the temporal prediction motion vector as a candidate for a prediction motion vector when the frame motion determination unit determines that the encoding target frame is a fixed-captured video. When the frame motion determination unit determines that the encoding target frame is not a fixed-captured video, the temporal motion vector predictor candidate is determined as a motion vector predictor candidate according to the minimum frame interval. The encoding apparatus according to claim 1, wherein it is determined whether or not to use.   The encoding apparatus according to claim 2, wherein the frame motion determination unit determines whether or not the encoding target frame is a fixed-captured video for each GOP. The program for functioning a computer as an encoding apparatus as described in any one of Claim 1 to 3.

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