WO2012113276A1

WO2012113276A1 - Video decoding method and encoding method, and terminal

Info

Publication number: WO2012113276A1
Application number: PCT/CN2012/070505
Authority: WO
Inventors: 杨名远; 林四新; 宋锦
Original assignee: 华为技术有限公司
Priority date: 2011-02-25
Filing date: 2012-01-18
Publication date: 2012-08-30
Also published as: CN102651814B; CN102651814A

Abstract

A video decoding method and encoding method, and a terminal. The decoding method comprises: acquiring an initial candidate motion vector set of a current block under decoding; removing candidate motion vectors not complying with a preset condition from the initial candidate motion vector set, and forming a new candidate motion vector set by use of remaining candidate motion vectors in the initial candidate motion vector set; and performing decoding according to the new candidate motion vector set. In the embodiment of the present application, some motion vectors can be removed, according to the preset condition, from the candidate motion vector set. On the condition that the number of the candidate motion vectors is decreased, the amount of information of reconstructed pixels in a reference frame obtained according to each candidate motion vector is decreased accordingly. Meanwhile, these candidate motion vectors are adjacent to each other, and selected reference blocks overlap each other, so that the reference blocks can be reused. As a result, the frequency of memory reading is decreased, hardware design is simplified, and encoding/decoding performance is improved.

Description

Video decoding method, encoding method and terminal

The present application claims priority to Chinese Patent Application No. 201110046270.2, entitled "Video Decoding Method, Coding Method, and Terminal", filed on Feb. 25, 2011, the entire contents of in.

Technical field

The present application relates to the field of communications technologies, and in particular, to a video decoding method, an encoding method, and a terminal.

Background technique

Motion prediction and motion compensation are important technologies in video compression. Some bits in the video compression code stream are used to transmit motion vector information, especially in the case of low bit rate, for high-definition video, it is used to transmit motion vector information. The bits typically exceed fifty percent of the total number of bits in the stream. For video encoding of continuous motion pictures, how many consecutive images are divided? Three types, B, and I, taking B frame as an example, which compresses the frame according to different points of the adjacent previous frame, the current frame, and the subsequent frame data, that is, the B frame can be based on the previous frame. And the next frame gets the motion vector set. Therefore, in order to improve coding efficiency, in the prior art, motion vector information of some coding blocks or decoding blocks is not written in the coded stream that is encoded or decoded, but the motion vector information is recovered by a certain search/derivation method. .

Still taking the B frame as an example, a decoding motion vector search derivation scheme in the prior art is: assuming that the current B frame to be decoded is fh, the previous frame and the next frame of fh are used as their reference frames, respectively, fn-1 And fn+l. Obtaining a candidate motion vector set for the current coding block in the B frame, obtaining reconstructed pixel information in the reference frame according to each candidate motion vector in the candidate motion vector set, and obtaining several reference blocks of the current coding block by deriving the reconstructed pixel information Then, based on the matching error calculation between the front and rear reference blocks, the candidate motion vector with the smallest matching error is used as the motion vector of the current coding block, or as the predicted motion vector for the current coding block reference.

In the prior art, when the number of candidate motion vectors in the candidate motion vector set is large, after reconstructing the pixel information in the reference frame obtained from each candidate motion vector, it is necessary to frequently read the memory to obtain reconstructed pixel information, so as to derive corresponding The reference block, the number of reads is consistent with the number of candidate motion vectors included. It can be seen that the more candidate motion vectors in the candidate motion vector set, the more frequently the memory is read, thereby improving the hardware design difficulty and reducing the performance of the codec. Summary of the invention

The embodiment of the present invention provides a video decoding method, an encoding method, and a terminal, so as to solve the problem that the number of candidate motion vectors is large, resulting in frequent reading of memory and reduced encoding and decoding performance.

The embodiment of the present application discloses the following technical solutions:

A video decoding method includes:

Obtaining an initial candidate motion vector set of the current decoded block;

Removing candidate motion vectors that do not meet the preset condition from the initial candidate motion vector set, and remaining candidate motion vectors composing a new candidate motion vector set;

Decoding is performed according to the new candidate motion vector set.

A video decoding terminal includes:

An obtaining unit, configured to acquire an initial candidate motion vector set of the current decoded block;

a screening unit, configured to remove candidate motion vectors that do not meet preset conditions from the initial candidate motion vector set, and the remaining candidate motion vectors form a new candidate motion vector set;

And a decoding unit, configured to perform decoding according to the new candidate motion vector set.

A video encoding method, including:

Obtaining an initial candidate motion vector set of the current coding block;

Encoding is performed according to the new candidate motion vector set.

A video encoding terminal includes:

An acquiring unit, configured to acquire an initial candidate motion vector set of the current coding block;

And a coding unit, configured to perform coding according to the new candidate motion vector set.

It can be seen from the foregoing embodiment that, in the encoding and decoding process in the embodiment of the present application, an initial candidate motion vector set of a current coding block or a decoding block is obtained, and candidate motion vectors that do not meet the preset condition are removed from the initial candidate motion vector set. The remaining candidate motion vectors form a new candidate motion vector set, and are encoded or decoded according to the new candidate motion vector set. Applying the embodiment of the present application, some motion vectors may be removed from the candidate motion vector set according to preset conditions, and the number of candidate motion vectors is reduced. In the case of less, the number of reconstructed pixel information in the reference frame obtained according to each candidate motion vector is also correspondingly reduced, and since the candidate motion vectors are relatively close, the reference blocks taken overlap each other, so that the reference block can be reused, thus reducing The frequency of memory reads simplifies hardware design and improves codec performance. DRAWINGS

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below, and it will be apparent to those skilled in the art that In other words, other drawings can be obtained based on these drawings without paying for creative labor.

1A is a flowchart of a first embodiment of a video decoding method according to the present application;

1B is a schematic diagram of motion vector selection of a decoding block in a B frame having a bidirectional motion compensation characteristic; FIG. 2A is a flowchart of a second embodiment of a video decoding method according to the present application;

2B is a schematic diagram of determining a center point in an embodiment of the present application;

2C is a schematic diagram of a candidate motion vector in the embodiment of the present application;

2D is a schematic diagram of adding a filtering window in the embodiment of the present application;

3 is a flowchart of a third embodiment of a video decoding method of the present application;

4 is a flowchart of a fourth embodiment of a video decoding method according to the present application;

FIG. 5 is a flowchart of a fifth embodiment of a video decoding method according to the present application;

6 is a flowchart of an embodiment of a video encoding method of the present application;

7A is a block diagram of an embodiment of a video decoding terminal of the present application;

Figure 7B is a block diagram of an embodiment of a screening unit of Figure 7A;

Figure 7C is a block diagram of an embodiment of another screening unit of Figure 7A;

Figure 7D is a block diagram of an embodiment of another screening unit of Figure 7A;

Figure 7E is a block diagram of an embodiment of another screening unit of Figure 7A;

FIG. 8 is a block diagram of an embodiment of a video encoding terminal of the present application.

detailed description

The following embodiments of the present invention provide a video decoding method, an encoding method, and a terminal.

In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, and to enable The above described objects, features and advantages of the embodiments of the present invention will be more apparent and understood. Referring to FIG. 1A, a flowchart of a first embodiment of a video decoding method of the present application is as follows:

Step 101: Acquire an initial candidate motion vector set of the current decoded block.

Specifically, the spatial domain candidate motion vector may be obtained according to the peripheral decoding block of the current decoding block, and the time domain candidate motion vector of the current decoding block is obtained according to the reference frame, where the reference frame is the previous frame of the current frame where the current decoding block is located, or the latter one. The frame, or the previous frame and the subsequent frame, form a spatial candidate motion vector and a time domain candidate motion vector into a set of initial candidate motion vectors.

Referring to Fig. 1B, a motion vector selection scheme for a decoded block in a B frame having a bidirectional motion compensation characteristic is shown. The decoding block mv in the current frame is the current decoding block, and the peripheral decoding block of the current decoding block mv generally refers to the left decoding block mva, the upper decoding block mvb, the upper right decoding block mvc of the mv shown in FIG. 1B, The upper left decoding block mvd obtains the spatial candidate motion vector of the current decoding block mv according to the above decoding blocks mva, mvb, mvc, mvd; assuming that the reference frame is the previous frame in the current frame as an example, the current decoding block The decoding block at the corresponding position of mv in the previous frame is mvcol, and the four-neighbor and eight-neighbor decoding blocks of the corresponding mvcol are mvO to mv7, respectively, and the time domain candidate motion vector of mv is obtained according to the above mvcol and mvO to mv7, For example, the time domain candidate motion vector may also be obtained according to the decoding block mvcol' at the corresponding position in the next frame of the current decoding block mv and its four neighborhoods and eight neighborhood decoding blocks mvO, to mv7.

Step 102: Remove candidate motion vectors that do not meet the preset condition from the initial candidate motion vector set, and the remaining candidate motion vectors form a new candidate motion vector set.

The method for removing the candidate motion vector according to the preset condition may be multiple, including: calculating a reference point according to the candidate motion vector in the initial candidate motion vector set, and setting a filtering for selecting the candidate motion vector with the reference point as a center A window that removes candidate motion vectors that are not included in the filter window.

Alternatively, the reference points are calculated according to the candidate motion vectors in the initial candidate motion vector set, the distance between each candidate motion vector and the reference point is compared, and the candidate motion vectors whose distance is greater than the preset threshold are removed.

Or, obtain the starting point position of the current decoded block, and use the starting point position as a reference point, compare each The distance between the candidate motion vectors and the reference point, and the candidate motion vectors whose distance is greater than the preset threshold are removed.

Or, respectively calculating a component vector sum of each candidate motion vector, each component vector sum being the sum of the absolute values of the horizontal motion vector and the vertical motion vector for each candidate motion vector, starting from the largest component vector sum, according to the component vector And in descending order, a preset number of component vector sums are extracted, and the extracted component vectors and the corresponding candidate motion vectors are removed.

The foregoing describes the preferred methods for removing candidate motion vectors in the embodiments of the present application. It should be noted that the embodiments of the present application are not limited to the foregoing manners, and no matter what preset conditions are set, the purpose is to select candidate motions. A certain number of candidate motion vectors are removed from the vector set to achieve the purpose of reducing memory reading.

Step 103: Perform decoding according to the new candidate motion vector set.

After obtaining the new candidate motion vector set, the existing decoding end derivation technique may be used, for example, using the candidate motion vector in the new candidate motion vector set, and the reference decoding block of the current decoding block is respectively obtained in the front and rear reference frames. Calculating the matching error between the reference decoding blocks before and after the calculation, for example, the matching error may be the absolute error sum of each corresponding pixel between the two reference decoding blocks, and the motion vector with the smallest matching error is used as the motion vector of the current decoding block. Or as a predicted motion vector for reference to the current decoded block. Obtaining a reference decoding block of the current decoded block according to the obtained motion vector or the predicted motion vector, and performing motion compensation on the decoding end to obtain a reconstructed value of the current decoded block.

Correspondingly, the video encoding terminal uses a process of generating a new candidate motion vector set consistent with the video decoding terminal and selecting a motion vector as the motion vector of the current coding block or as a prediction motion vector for the current coding block reference. The video encoding terminal may encode the difference between the selected motion vector and the real motion vector into the code stream, and transmit the code stream to the video decoding terminal. Therefore, after analyzing the code stream, the video decoding terminal can obtain the difference between the selected motion vector and the real motion vector, and add the selected motion vector and the difference to obtain the coded terminal real coded motion vector. Referring to FIG. 2A, a flowchart of a second embodiment of a video decoding method of the present application, which illustrates a process of removing candidate motion vectors by setting a filtering window:

Step 201: Acquire an initial candidate motion vector set of the current decoded block.

Specifically, the spatial domain candidate motion vector may be obtained according to the peripheral decoding block of the current decoding block, according to The reference frame obtains the time domain candidate motion vector of the current decoded block, and the reference frame is the previous frame of the current frame in which the current decoded block is located, or the next frame, or the previous frame and the subsequent frame, and the spatial domain candidate motion vector and the time domain are obtained. The candidate motion vectors constitute a set of initial candidate motion vectors.

Step 202: Calculate a reference point according to the candidate motion vector in the initial candidate motion vector set. The reference point may be a center point of all candidate motion vectors in the candidate motion vector set, or a center of gravity point of all candidate motion vectors in the candidate motion vector set, or a median point of all candidate motion vectors in the candidate motion vector set. The following describes how each reference point is obtained:

Taking the reference point as the center, the average value of the horizontal motion vectors of all candidate motion vectors and the average of the vertical motion vectors of all candidate motion vectors are calculated, and the average of the horizontal motion vectors and the average of the vertical motion vectors are composed. The point represented by the motion vector is taken as the center. In the embodiment of the present application, the point in the upper left corner of the rectangle formed by the current decoding block may be used as the origin of the vector coordinate system. 2B is a schematic diagram of determining a center point in the embodiment of the present application. Referring to FIG. 2C, it is a schematic diagram of candidate motion vectors in an embodiment of the present application, where MV1 to MV7 are seven candidate motion vectors in the candidate motion vector set.

Taking the reference point as the center of gravity as an example, all candidate motion vectors in the candidate motion vector are sorted in descending order, and then the candidate motion vector is accumulated in descending order with the largest candidate motion vector as a starting point. Starting from the smallest candidate motion vector, the candidate motion vectors are accumulated in order from small to large, and the accumulation in the two directions cannot have overlapping candidate motion vectors until the difference between the two directions is the smallest, and this is selected. In the case where the result value is larger in the two directions, the point corresponding to the last accumulated motion vector is taken as the center of gravity.

Taking the reference point as the median point as an example, all candidate motion vectors in the candidate motion vector are sorted in descending order, and then the point corresponding to the candidate motion vector in the middle is selected as the median point.

The candidate motion vector in the above embodiment is usually a two-dimensional candidate motion vector, so the center, the center of gravity, or the median value can usually be acquired separately according to the two dimensions.

Step 203: Set a filter window for selecting a candidate motion vector centering on the reference point. Centering on the reference point determined in step 202, a filtering window is set, and the size of the filtering window can be adaptively adjusted according to the size of the current decoding block.

Taking the reference point as the center, take the center as the origin and set a length and width of the decoded block. The filter window. Referring to FIG. 2D, it is a schematic diagram of adding a filtering window in the embodiment of the present application. Step 204: Remove candidate motion vectors that are not included in the filtering window, and the remaining candidate motion vectors constitute a new candidate motion vector set.

Still described in conjunction with FIG. 2D, after the filter window is set, wherein the candidate motion vectors MV1 to MV6 are still located in the filter window, and the MV7 is located outside the filter window, indicating that the MV7 does not belong to the selected candidate motion vector selection range. Therefore, MV7 is removed from the candidate motion vector set.

Step 205: Perform decoding according to the new candidate motion vector set.

The process of decoding according to the new candidate motion vector set is consistent with the prior art. For a general description, refer to the foregoing step 103, and details are not described herein again. Referring to FIG. 3, it is a flowchart of a third embodiment of a video decoding method according to the present application. The embodiment shows a process for removing a candidate motion vector by comparing a distance from a reference point:

Step 301: Acquire an initial candidate motion vector set of the current decoded block.

Step 302: Calculate a reference point according to the candidate motion vector in the initial candidate motion vector set. The process of calculating the reference point in this step is the same as step 202, and will not be repeated here.

Step 303: Compare the distance between each candidate motion vector and the reference point.

Taking the reference point as the center, the distance between each candidate motion vector and the center is calculated separately, and the calculated distances are arranged in descending order, and the candidate motion vectors whose distance is greater than the threshold may be selected subsequently.

Step 304: Remove candidate motion vectors whose distance is greater than a preset threshold, and the remaining candidate motion vectors constitute a new candidate motion vector set.

Step 305: Perform decoding according to the new candidate motion vector set.

The process of decoding according to the new candidate motion vector set is consistent with the prior art. For a general description, refer to the foregoing step 103, and details are not described herein again.

Referring to FIG. 4, it is a flowchart of a fourth embodiment of a video decoding method of the present application, which shows Another process of removing candidate motion vectors by comparing the distance from the reference point:

Step 401: Acquire an initial candidate motion vector set of the current decoded block.

Step 402: Obtain a starting point position of the current decoding block, and use the starting point position as a reference point. In this embodiment, the starting point position of the current decoding block is used as a reference point, and the starting point position generally refers to the position of the point in the upper left corner of the current decoding block. Compared with the foregoing embodiment, the way of directly determining the reference point avoids the calculation of the reference point, and the speed of screening the candidate motion vector can be correspondingly improved.

Step 403: Compare the distance between each candidate motion vector and the reference point.

The distance between each candidate motion vector and the starting point of the current decoding block is calculated separately, and the calculated distances are arranged in descending order, and the candidate motion vectors whose distance is greater than the threshold may be selected subsequently.

Step 404: Remove candidate motion vectors whose distance is greater than a preset threshold, and the remaining candidate motion vectors constitute a new candidate motion vector set.

Step 405: Perform decoding according to the new candidate motion vector set.

The process of decoding according to the new candidate motion vector set is consistent with the prior art. For a general description, refer to the foregoing step 103, and details are not described herein again. Referring to FIG. 5, it is a flowchart of a fifth embodiment of a video decoding method according to the present application. The embodiment shows a process of calculating a component vector and removing a candidate motion vector by using:

Step 501: Acquire an initial candidate motion vector set of the current decoded block.

Step 502: Calculate component sums of each candidate motion vector separately, and each component vector sum is the sum of the absolute values of the horizontal motion vector and the vertical motion vector for each candidate motion vector. Suppose there are two candidate motion vectors, mvO and mvl respectively, then their horizontal motion vectors are mvO-X and mvl-X, respectively, and the vertical motion vectors are mvO-y and mvl-y, respectively, and then each candidate is calculated according to the following formula. The component vector of the motion vector and:

Mv_sadi = |mvi_x| + ||mvi_y |

In the above formula, mv_sadi is the component vector sum of the i-th candidate motion vector, mvi_x is the horizontal motion vector of the i-th candidate motion vector, and mvi_y is the vertical motion vector of the i-th candidate motion vector. It is then sorted according to the calculated mv-sadi, for example, sorted from large to small.

Step 503: Extract a preset number of component vector sums according to the component vectors and the order from the largest component vector sum.

Step 504: The extracted component vector and the corresponding candidate motion vector are removed, and the remaining candidate motion vectors constitute a new candidate motion vector set.

Step 505: Perform decoding according to the new candidate motion vector set.

With the decoding method in the foregoing embodiment of the present application, some motion vectors may be removed from the candidate motion vector set according to a preset condition, and in the case that the number of candidate motion vectors is reduced, the reconstructed pixels in the reference frame are obtained according to each candidate motion vector. The amount of information is also reduced accordingly, thus reducing the frequency of memory reads, simplifying hardware design, and improving decoding performance. Corresponding to the foregoing video decoding method embodiment of the present application, the present application also provides an embodiment of a video encoding method. The manner in which the candidate motion vector set is generated in the video encoding process of the present application is consistent with the video decoding process, except that the video encoding process completes the video encoding according to the generated new candidate motion vector set.

Referring to FIG. 6, a flowchart of an embodiment of a video encoding method of the present application is as follows:

Step 601: Acquire an initial candidate motion vector set of the current coding block.

Specifically, the spatial candidate motion vector may be obtained according to the peripheral coding block of the current coding block, and the time domain candidate motion vector of the current coding block is obtained according to the reference frame, where the reference frame is the previous frame of the current frame where the current coding block is located, or the latter The frame, or the previous frame and the subsequent frame, form a spatial candidate motion vector and a time domain candidate motion vector into a set of initial candidate motion vectors. Step 602: Remove candidate motion vectors that do not meet the preset condition from the initial candidate motion vector set, and the remaining candidate motion vectors form a new candidate motion vector set.

Or, obtain a starting point position of the current coding block, use a starting point position as a reference point, compare a distance between each candidate motion vector and a reference point, and remove a candidate motion vector whose distance is greater than a preset threshold.

Step 603: Perform coding according to the new candidate motion vector set.

After obtaining the new candidate motion vector set, the existing decoding end derivation technique may be used, for example, using the candidate motion vector in the new candidate motion vector set, and the reference coding block of the current coding block is respectively obtained in the front and rear reference frames. Calculating a matching error between the reference code blocks before and after, for example, the matching error may be the absolute error sum of each corresponding pixel between the two reference code blocks, and the motion vector with the smallest matching error is used as the motion vector of the current coded block, Or as a predicted motion vector for reference to the current coding block. The residual value of the reference code block is subtracted from the original value of the current coded block to obtain a residual value, and the residual value is encoded and transmitted to the decoding end.

The process of constructing a new candidate motion vector set in the above encoding process and the foregoing decoding method The second to fifth embodiments are identical, and are not described herein again. With the above encoding method in the embodiment of the present application, some motion vectors may be removed from the candidate motion vector set according to a preset condition, and in the case that the number of candidate motion vectors is reduced, the reconstructed pixels in the reference frame are obtained according to each candidate motion vector. The number of information is correspondingly reduced, and since the candidate motion vectors are relatively close, the reference blocks taken overlap each other, so that the reference block can be reused, thereby reducing the frequency of memory reading, simplifying hardware design, and improving. Coding performance. Corresponding to the foregoing embodiments of the video decoding method and the video encoding method of the present application, the present application further provides a block diagram of an embodiment of a video decoding terminal and a video encoding terminal.

7A is a block diagram of an embodiment of a video decoding terminal of the present application:

The video decoding terminal includes: an obtaining unit 710, an array selecting unit 720, and a decoding unit 730. The obtaining unit 710 is configured to obtain an initial candidate motion vector set of the current decoding block, and the filtering unit 720 is configured to remove candidate motion vectors that do not meet the preset condition from the initial candidate motion vector set, and the remaining candidate motion vectors. Composing a new set of candidate motion vectors;

The decoding unit 730 is configured to perform decoding according to the new candidate motion vector set. Referring to Figure 7B, a block diagram of an embodiment of a screening unit in Figure 7A:

The screening unit 720 can include:

a first reference point calculation unit 7211, configured to calculate a reference point according to the candidate motion vector in the initial candidate motion vector set; wherein, the reference point may be specifically a center point of all candidate motion vectors in the candidate motion vector set; or a center of gravity point of all candidate motion vectors in the candidate motion vector set; or a median point of all candidate motion vectors in the candidate motion vector set;

a filter window setting unit 7212, configured to set, by the reference point, a filter window for selecting a candidate motion vector;

The first motion vector removing unit 7213 is configured to remove candidate motion vectors that are not included in the filtering window. Referring to Figure 7C, a block diagram of an embodiment of another screening unit in Figure 7A:

The screening unit 720 can include: a second reference point calculation unit 7221, configured to calculate a reference point according to the candidate motion vector in the initial candidate motion vector set; wherein, the reference point may be specifically a center point of all candidate motion vectors in the candidate motion vector set; or a center of gravity point of all candidate motion vectors in the candidate motion vector set; or a median point of all candidate motion vectors in the candidate motion vector set;

The first distance comparing unit 7222 is configured to compare a large distance between each candidate motion vector and the reference point;

The second motion vector removing unit 7223 is configured to remove the candidate motion vector whose distance is greater than a preset threshold. Referring to Figure 7D, a block diagram of an embodiment of another screening unit in Figure 7A:

The screening unit 720 can include:

a reference point obtaining unit 7231, configured to acquire a starting point position of the current decoding block, and use the starting point position as a reference point;

a second distance comparing unit 7232, configured to compare a distance between each candidate motion vector and the reference point;

The third motion vector removing unit 7233 is configured to remove the candidate motion vector whose distance is greater than a preset threshold. Referring to Figure 7E, a block diagram of an embodiment of another screening unit in Figure 7A:

The screening unit 720 can include:

a component vector sum calculation unit 7241, configured to separately calculate a component vector sum of each candidate motion vector, and each component vector sum is a sum of absolute values of a horizontal motion vector and a vertical motion vector for each candidate motion vector;

a component vector sum extraction unit 7242, configured to extract a preset number of component vector sums according to the component vector and the order from the largest component vector sum;

The fourth motion vector removing unit 7243 is configured to remove the extracted component vector and the corresponding candidate motion vector. Referring to FIG. 8, a block diagram of an embodiment of a video encoding terminal of the present application is as follows: The video encoding terminal includes: an obtaining unit 810, a filtering unit 820, and an encoding unit 830. The obtaining unit 810 is configured to obtain an initial candidate motion vector set of the current coding block, and the filtering unit 820 is configured to remove candidate motion vectors that do not meet the preset condition from the initial candidate motion vector set, and the remaining candidate motion vectors. Composing a new set of candidate motion vectors;

The coding unit 830 is configured to perform coding according to the new candidate motion vector set.

Specifically, the screening unit 820 can include (not shown in FIG. 8):

a first reference point calculation unit, configured to calculate a reference point according to the candidate motion vector in the initial candidate motion vector set; and a filter window setting unit, configured to set, according to the reference point, a candidate motion vector to be selected a filter window; a first motion vector removing unit, configured to remove a candidate motion vector that is not included in the filter window; wherein the reference point may be specifically a center point of all candidate motion vectors in the candidate motion vector set; or a center of gravity point of all candidate motion vectors in the candidate motion vector set; or a median point of all candidate motion vectors in the candidate motion vector set; or a second reference point calculation unit, configured to use the initial candidate motion vector a candidate motion vector in the set calculates a reference point; a first distance comparing unit, configured to compare a distance between each candidate motion vector and the reference point; and a second motion vector removing unit, configured to remove the distance greater than a preset a candidate motion vector of a threshold; wherein the reference point may be specifically the candidate motion vector Set a central point for all candidate motion vectors; or the center of gravity of the set of candidate motion vectors for all candidate motion vectors; or value point of all the candidate motion vector set in the candidate motion vectors; or

a reference point obtaining unit, configured to acquire a starting point position of the current coding block, using the starting point position as a reference point; and a second distance comparing unit, configured to compare each candidate motion vector with the reference point a third motion vector removing unit, configured to remove the candidate motion vector whose distance is greater than a preset threshold; or

a component vector sum calculation unit for respectively calculating a component vector sum of each candidate motion vector, each component vector sum being a sum of absolute values of a horizontal motion vector and a vertical motion vector for each candidate motion vector; a component vector and an extracting unit And for extracting, from the largest component vector sum, a preset number of component vectors according to the component vector and the order of the largest and smallest, and a fourth motion vector removing unit, configured to remove the extracted component vector sum The corresponding candidate motion vector.

The description of the foregoing embodiment shows that, in the encoding and decoding process in the embodiment of the present application, an initial candidate motion vector set of a current coding block or a decoding block is obtained, from the initial candidate motion vector set. The candidate motion vectors that do not meet the preset condition are removed, and the remaining candidate motion vectors form a new candidate motion vector set, and are encoded or decoded according to the new candidate motion vector set. Applying the embodiments of the present application, some motion vectors may be removed from the candidate motion vector set according to preset conditions. When the number of candidate motion vectors is reduced, the number of reconstructed pixel information in the reference frame obtained according to each candidate motion vector is also reduced accordingly. At the same time, since the candidate motion vectors are relatively close, the reference blocks taken overlap each other, so that the reference block can be reused, thereby reducing the frequency of memory reading, simplifying hardware design, and improving codec performance.

Further, since the motion of the object has a regularity and a space-time correlation, the motion vector of the adjacent coded block is often limited to a small range. Therefore, the method of the embodiment of the present application can limit the reading under the premise of ensuring the coding performance. The size of the memory. Since the candidate motion vectors are likely to be reduced, and most of the candidate motion vectors are closely spaced, the selected regions of the candidate motion vectors can be defined to read the defined regions. For example, if there are currently 8 candidate motion vectors, which are close to each other, the reconstructed pixels may be overlapped according to the reference frame obtained by motion compensation according to the motion vector, and the reference in the buffer is transferred from the memory according to the defined region. The frame reconstruction pixels are reduced; and since the defined regions are connected together, it is convenient to perform one-time reading without step-by-step reading according to the number of candidate motion vectors, thereby further simplifying the hardware design. Improve codec performance. It will be apparent to those skilled in the art that the techniques in the embodiments of the present invention can be implemented by means of software plus a necessary general hardware platform. Based on such understanding, the technical solution in the embodiments of the present invention may be embodied in the form of a software product in essence or in the form of a software product, which may be stored in a storage medium such as a ROM/RAM. , a diskette, an optical disk, etc., includes instructions for causing a computer device (which may be a personal computer, server, or network device, etc.) to perform the methods described in various embodiments of the present invention or in some portions of the embodiments.

The technology provided by the embodiments of the present invention can be applied in the field of digital signal processing, and is implemented by a video encoder and a decoder. Video encoders, decoders are widely used in a variety of communication equipment or electronic equipment, such as: digital TV, set-top box, media gateway, mobile phone, wireless device, personal data assistant (PDA), handheld or portable computer, GPS receiver / navigator, camera, video player, camcorder, video recorder, surveillance equipment, video conferencing and video telephony equipment, etc. Such devices include processors, memory, and interfaces for transmitting data. Video codecs can be directly digital circuits or chips such as DSP (Digital Signal Processor) implementation, or software code to drive a processor to execute the process in the software code.

The various embodiments in the specification are described in a progressive manner, and the same parts of the various embodiments may be referred to each other, and each embodiment focuses on differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the description of the method embodiment.

The embodiments of the present invention described above are not intended to limit the scope of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and scope of the invention are intended to be included within the scope of the invention.

Claims

Rights request

A video decoding method, comprising:

Obtaining an initial candidate motion vector set of the current decoded block;

Removing candidate motion vectors that do not meet the preset condition from the initial candidate motion vector set, and composing the remaining candidate motion vectors in the initial candidate motion vector set to form a new candidate motion vector according to the new candidate motion vector set Decode.

2. The method according to claim 1, wherein the removing the candidate motion vector that does not meet the preset condition from the initial candidate motion vector set comprises:

Calculating a reference point according to the candidate motion vector in the initial candidate motion vector set; setting a filter window for selecting the candidate motion vector centering on the reference point; removing the candidate motion vector not included in the filter window .

The method according to claim 1, wherein the removing the candidate motion vector that does not meet the preset condition from the initial candidate motion vector set comprises:

Calculating reference points according to candidate motion vectors in the initial candidate motion vector set; comparing distances between each candidate motion vector and the reference point;

The candidate motion vector whose distance is greater than a preset threshold is removed.

The method according to claim 2 or 3, wherein the reference point comprises: a center point of all candidate motion vectors in the candidate motion vector set; or

a center of gravity of all candidate motion vectors in the candidate motion vector set; or

a median point of all candidate motion vectors in the set of candidate motion vectors.

Obtaining a starting point position of the current decoding block, using the starting point position as a reference point; comparing a distance between each candidate motion vector and the reference point;

Calculate the component vector sum of each candidate motion vector separately, and each component vector sum is for each candidate The sum of the horizontal motion vector of the motion vector and the absolute value of the vertical motion vector;

Extracting a predetermined number of component vector sums from the largest component vector sum, in order of the component vectors and from largest to smallest;

The extracted component vector and the corresponding candidate motion vector are removed.

7. A video decoding terminal, comprising:

a filtering unit, configured to remove, from the initial candidate motion vector set, a candidate motion vector that does not meet a preset condition;

a merging unit, configured to group the remaining candidate motion vectors in the initial candidate motion vector set into a new candidate motion vector set;

The terminal according to claim 7, wherein the screening unit comprises: a first reference point calculating unit, configured to calculate a reference point according to candidate motion vectors in the initial candidate motion vector set;

a filter window setting unit, configured to set, by the reference point, a filter window for selecting a candidate motion vector;

A first motion vector removing unit is configured to remove candidate motion vectors that are not included in the filtering window.

The terminal according to claim 7, wherein the screening unit comprises: a second reference point calculating unit, configured to calculate a reference point according to candidate motion vectors in the initial candidate motion vector set;

a first distance comparing unit, configured to compare a distance between each candidate motion vector and the reference point;

And a second motion vector removing unit, configured to remove the candidate motion vector whose distance is greater than a preset threshold.

The terminal according to claim 7, wherein the screening unit comprises: a reference point acquiring unit, configured to acquire a starting point position of the current decoding block, and use the starting point position as a reference point; a second distance comparing unit, configured to compare a distance between each candidate motion vector and the reference point;

And a third motion vector removing unit, configured to remove the candidate motion vector whose distance is greater than a preset threshold.

The terminal according to claim 7, wherein the screening unit comprises: a component vector and a calculating unit, configured to respectively calculate a component vector sum of each candidate motion vector, and each component vector sum is for each candidate The sum of the horizontal motion vector of the motion vector and the absolute value of the vertical motion vector;

a component vector sum extracting unit, configured to extract a preset number of component vector sums according to the component vector and the order of the component vectors from the largest component vector sum;

And a fourth motion vector removing unit, configured to remove the extracted component vector and the corresponding candidate motion vector.

12. A video encoding method, comprising:

Obtaining an initial candidate motion vector set of the current coding block;

Removing candidate motion vectors that do not meet the preset condition from the initial candidate motion vector set, and composing the remaining candidate motion vectors in the initial candidate motion vector set to form a new candidate motion vector according to the new candidate motion vector set Encode.

The method according to claim 12, wherein the removing the candidate motion vector that does not meet the preset condition from the initial candidate motion vector set comprises:

The method according to claim 13 or 14, wherein the reference point comprises: a center point of all candidate motion vectors in the candidate motion vector set; or

Obtaining a starting point position of the current coding block, using the starting point position as a reference point; comparing a distance between each candidate motion vector and the reference point;

17. The method according to claim 12, wherein the removing the candidate motion vector that does not meet the preset condition from the initial candidate motion vector set comprises:

Calculating a sum of component vectors for each candidate motion vector, each component vector sum being the sum of the absolute values of the horizontal motion vector and the vertical motion vector for each candidate motion vector;

18. A video encoding terminal, comprising:

The terminal according to claim 18, wherein the screening unit comprises: a first reference point calculating unit, configured to calculate a reference point according to candidate motion vectors in the initial candidate motion vector set;

a filter window setting unit, configured to set, by the reference point, a filter window for selecting a candidate motion vector; And a first motion vector removing unit, configured to remove a candidate motion vector that is not included in the filtering window.

The terminal according to claim 18, wherein the screening unit comprises: a second reference point calculating unit, configured to calculate a reference point according to candidate motion vectors in the initial candidate motion vector set;

The terminal according to claim 18, wherein the screening unit comprises: a reference point obtaining unit, configured to acquire a starting point position of the current coding block, and use the starting point position as a reference point;

a second distance comparing unit, configured to compare a distance between each candidate motion vector and the reference point;

The terminal according to claim 17, wherein the screening unit comprises: a component vector and a calculating unit, configured to respectively calculate component vector sums of each candidate motion vector, each component vector sum being each candidate The sum of the horizontal motion vector of the motion vector and the absolute value of the vertical motion vector;