WO2013064112A1

WO2013064112A1 - Method and device of video image filtering process

Info

Publication number: WO2013064112A1
Application number: PCT/CN2012/084070
Authority: WO
Inventors: 张新峰; 马思伟; 杨名远
Original assignee: 华为技术有限公司
Priority date: 2011-11-04
Filing date: 2012-11-05
Publication date: 2013-05-10
Also published as: CN103096054A; CN103096054B

Abstract

Disclosed in the embodiments of the present invention are a method and device of video image filtering process. The method comprises the steps of receiving a stream of encoded video slices; obtaining at least two Adaptation Parameter Set (APS) identifications from a video slice header, the at least two APSs being respectively used to store at least two filter parameters, wherein each of the APSs stores at least two filter parameters, and the number of APS identifications in the video slice header is the same as the number of the filter parameters; respectively obtaining the at least two filter parameters according to the at least two APS identifications; and performing the filtering process on the video slices by using the at least two filter parameters.

Description

Video image filtering processing method and device

The present invention relates to video codec technology in the field of digital signal processing technology, and more particularly to a video image filtering processing method and apparatus. Background technique

In the field of digital communications, voice, image, audio, and video transmissions have a wide range of application requirements, such as mobile phone calls, audio and video conferencing, broadcast television, multimedia entertainment, and the like. With the development of network technology, video on demand, Internet TV, videophone, etc. have become the main business of broadband networks, and these services will become the main business of the 3G (the 3rd generation) wireless network. In order to reduce the resources occupied during the storage or transmission of the video signal, the video signal is compressed and processed at the transmitting end and transmitted to the receiving end, and the receiving end recovers the video signal and plays it by decompressing.

A video encoding method generally divides a video image into a plurality of video frames, each video frame is further divided into a plurality of slices (video strips), and each slice is encoded, and the decoding end decodes the information, and then Composite into a video frame. In the video coding technology based on Slice, in order to improve coding efficiency, ALF (Adaptive Loop Filter) and SAO (Sample Adaptive Offset) post-processing techniques are introduced.

The ALF technique refers to training multiple sets of filter parameters by decoding the reconstructed image and the original input image, filtering the coded reconstructed image, improving the reconstructed image quality, and improving the motion compensation prediction performance inside the coding loop, thereby improving the coding. effectiveness.

The SA0 technology classifies the pixels of the decoded reconstructed image according to the edge information and the intensity information, and improves the quality of the reconstructed image by correcting each type of pixel by using the pixel adaptive offset parameter, and passes through the coding loop. Improve motion compensation prediction performance, and thus improve coding efficiency.

ALF and SA0 need to record more side information at the slice level, such as ALF filter coefficients, SA0 offset values, and so on. Because of the large correlation between image space and time, the ALF/SA0 parameters between different slices also have a large correlation. If you simply write these parameters in In the S ice header, when each frame has multiple SI ices, the parameters occupy more code rates and there is greater redundancy between them. Summary of the invention

An object of the embodiments of the present invention is to provide a video image filtering processing method and apparatus, which improve the flexibility of selecting a filtering parameter in a video encoding process.

According to an embodiment of the present invention, a video image filtering processing method is provided, including: receiving a video stripe encoded code stream;

Obtaining at least two APS identifiers from the video stripe header, the at least two APSs respectively for storing at least two filter parameters; wherein each ASP stores at least two filter parameters, in the video strip header The number of APS identifiers is the same as the number of filter parameters;

Obtaining the at least two filter parameters according to the at least two APS identifiers respectively;

The video strip is filtered using the at least two filter parameters.

According to another embodiment of the present invention, a video image filtering processing apparatus is provided, including: a receiving unit, configured to receive a video stripe encoded code stream;

An extracting unit, configured to obtain an identifier of at least two APSs from a video stripe header, where the at least two APSs are used to store at least two filter parameters, where each ASP stores at least two filter parameters, The number of the APS identifiers in the video stripe header is the same as the number of the filter parameters; the parameter obtaining unit is configured to obtain the at least two filter parameters according to the at least two APS identifiers respectively;

And a filtering unit, configured to filter the video strip by using the at least two filter parameters. In the embodiment of the present invention, at least two filter parameters are stored in the APS, and the parameters of the APS of the at least two filter parameters corresponding to the video strip are stored in the header of the video stripe, because at least one video stripe header includes at least Two APS identifiers can be obtained by different filter parameters from different APSs during decoding to improve the flexibility of filter parameter selection, thereby improving video coding efficiency. DRAWINGS

In order to more clearly illustrate the embodiments of the present invention 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. Obviously, the drawings in the following description are only It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any inventive labor.

1 is a sequence diagram of a video code stream;

2 is a schematic flowchart of a video image filtering processing method according to an embodiment of the present invention; FIG. 3 is a schematic flowchart of another embodiment of a video image filtering processing method according to the present invention; Schematic diagram

5 is a schematic flowchart of another embodiment of a video image filtering processing method according to the present invention; FIG. 6 is a schematic structural diagram of an embodiment of a video image filtering processing apparatus according to the present invention; FIG. 7 is a video image filtering processing provided by the present invention. FIG. 8 is a schematic structural diagram of another embodiment of a video image filtering processing apparatus according to the present invention. detailed description

BRIEF DESCRIPTION OF THE DRAWINGS The technical solutions in the embodiments of the present invention will be described in detail with reference to the accompanying drawings. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative work are within the scope of the present invention.

In the field of digital signal processing, video codecs are widely used in various electronic devices, such as: mobile phones, wireless devices, personal data assistants (PDAs), handheld or portable computers, GPS receivers/navigators, cameras, video playback. , camera, video recorder, monitoring equipment, etc. Generally, such an electronic device includes a video encoder or a video decoder, and the video encoder or decoder can be directly implemented by a digital circuit or a chip such as a DSP ( dig i ta ls igna l proces sor ), or the processor can be driven by software code. Implemented by executing the process in the software code.

In order to effectively store parameters such as ALF/SA0 of S li ce level, and reduce the correlation between these parameters in the airspace and time domain, and further improve coding efficiency, a technique proposes to use new high-level syntax elements. APS (Adaptation Parameter Set) to store parameters such as ALF/SAO. The technology stores the ALF and SA0 parameters into a given APS. Each APS is identified by a specific aps_id, and each alice header is written with aps_id used by the current slice, thus flexibly implementing ALF and SA0. The reuse of airspace and time domain parameters effectively reduces the redundancy of ALF and SA0 parameters.

Referring to FIG. 1, a sequence of video streams is processed in units of frames, and a video stream of each frame includes SPS (Sequence Parameter Set), PPS (Picture Parameter Set) , image parameter set), multiple APS and multiple video stripe information. The header information of the video stripe includes an aps_id indicating the APS identifier of the ALF and SA0 parameters corresponding to the video stripe. After receiving the code stream, the decoding end parses the sps, pps, sps, and Slice information, reconstructs the image according to the decoded information, obtains the ALF and SA0 parameters through the APS corresponding to the aps_id, and filters the reconstructed image by the ALF and SA0 parameters. The filtered reconstructed image output display is also stored in the buffer as a reference for the subsequent decoded frame.

However, this technique only writes an aps.id in the Slice header, which causes both ALF and SA0 to take advantage of the parameters in the same aps_id. The use of this ALF and SA0 parameter binding limits these two post-processing techniques. Performance, because the ALF and SA0 parameters in the same APS do not necessarily optimize the performance of both technologies at the same time. This technique limits the flexibility of selecting ALF and SA0 parameters.

Referring to FIG. 2, an embodiment of a video image filtering processing method of the present invention includes:

S201: Receive a video stripe coded code stream.

S202: Obtain an identifier of at least two APSs from a video stripe header, where the at least two APSs are used to store at least two filter parameters, where each ASP stores at least two filter parameters, and the video strips The number of APS identifiers in the header is the same as the number of filter parameters;

In one embodiment, the video strip header includes two APS identifiers for indicating where the ALF and SA0 parameters are stored. These two identifiers may or may not be the same.

S203: Obtain the at least two filter parameters according to the at least two APS identifiers respectively.

S204: Filter the video strip by using the at least two filter parameters. In the embodiment of the present invention, at least two filter parameters are stored in the APS, and the parameters of the APS of the at least two filter parameters corresponding to the video strip are stored in the header of the video stripe, because at least one video stripe header includes at least Two APS identifiers can obtain different filter parameters from different APSs during decoding, which improves the flexibility of filter parameter selection, thereby improving the processing performance of video coding. Referring to FIG. 3, in order to improve the flexibility of selecting ALF and SA0 parameters, another embodiment of the video image filtering processing method of the present invention includes:

S301: Receive a video stripe coded code stream.

Referring to FIG. 4, the video encoded code stream sequence at the decoding end includes: SPS, PPS, multiple APSs, and information of multiple video strips. After receiving the video encoded code stream, the decoding end parses the data of each data packet in turn, and includes a series of SPS packets, PPS packets, APS packet information (including parameter information of various filter groups therein), and each video strip. (Slice) data information.

S302: Obtain an identifier of a first APS for storing ALF parameters and a second APS identifier for storing SA0 parameters from a video stripe header; where each ASP stores an ALF parameter and an SA0 parameter; wherein, the video strip The header contains two APS identifiers, which are used to indicate where the ALF and SA0 parameters are stored. These two identifiers may or may not be the same. The order in which the ALF parameters and the SAO parameters are stored in the ASP may be the same as or different from the order of the APS identifiers in the video stripe header.

The syntax information of the video strip header is parsed, and the syntax element of the APS_ID is included, and the information of each APS-ID is analyzed in turn, and each filter group information used according to the parsing order of the APS-ID is performed.

For example, in the header information of Slice_c in Figure 4, two APS_IDs (APS_idl and APS_id2) need to be parsed, for example, corresponding to APS_a and APS_c respectively, then SI ice_c will use ALF (a) and SAO (c) (or ALF (c) and SAO. (a)) Perform a filtering operation on this video strip.

S303: Obtain an ALF parameter and an SA0 parameter according to the identifier of the first APS and the identifier of the second APS, respectively.

S304: Perform post processing on the video strip by using the ALF parameter and the SA0 parameter.

The ALF parameter is used for adaptive filtering, and the video strip is corrected by the SA0 parameter. These two post-processing techniques can also be seen as filtering. The syntax of the corresponding video stripe header is as follows:

}

If( slice_type = = B )

Collocated from 10—flag u(l) if( adaptive loop filter enabled flag 8L8L aps_adaptive_loop_filter_flag ) {

Byte_align()

Alf_cu_control_param( )

Byte_align()

}

In this embodiment, two APS identifiers are added to one video strip, and ALF parameters and SA0 parameters can be independently selected according to coding performance. Since one video strip header includes two APS identifiers, one video strip can be used. Each filter bank in different APSs is filtered to improve the flexibility of filter parameter selection, thereby improving the processing performance of video coding. Referring to FIG. 5, a method of another embodiment of the present invention includes:

S501: Receive a video stripe coded code stream;

Referring to FIG. 4, the video encoding code stream sequence at the decoding end includes: SPS, PPS, multiple APSs, and information of multiple video strips. After receiving the video encoded code stream, the decoding end parses the data of each data packet in turn, and includes a series of SPS packets, PPS packets, APS packet information (including parameter information of various filter groups therein), and each video strip. (S li ce ) data information.

S502: Obtain a parameter sharing identifier from the video stripe header, where the parameter shared identifier is used to indicate whether the ALF parameter and the SA0 parameter corresponding to the video stripe are stored in the same APS.

Parsing the syntax information of the video strip header, which includes the syntax element of the parameter shared identifier sao-a lf - share-aps -f lag. If the value is 0, it indicates that the strip shares each filter group in the same APS packet. After the information, only one APS_ID information needs to be parsed. If the value is 1, it indicates that the strip shares the information of each filter group in different APS packets, and then needs to parse multiple APS_ID information.

S503: If the parameter shared identifier indicates that the ALF parameter and the SA0 parameter corresponding to the video stripe are stored in different APSs, obtaining an identifier of the first APS for storing the ALF parameter from the video stripe header And an identifier of the second APS for storing the SAO parameter; wherein each ASP stores an ALF parameter and an SA0 parameter.

S504: Obtain an ALF parameter and an SA0 parameter according to the identifier of the first APS and the identifier of the second APS, respectively.

For example, if the header information of Slice_c in the above figure is sao_alf_share_aps_flag=0, and then an APS_ID needs to be parsed, such as APS_a, then SI ice_c will use ALF (a) and SAO (c) to filter the video stripe.

S505: If the parameter shared identifier indicates that the ALF parameter and the SA0 parameter corresponding to the video stripe are stored in the same APS, obtain a shared APS identifier from the video stripe header; wherein each ASP stores the ALF parameter and the SA0 parameter. ;

S506: Obtain the ALF parameter and the SA0 parameter from the ASP corresponding to the shared APS identifier. If the sao_alf-share_aps_f lag=l, and then need to resolve two APS_IDs, such as APS_a and APS_b, then 31 6_0 will use 1^ (&) and 3 0 (0) (or ALF (c) and SAO (a)) filter the video stripe.

S507: The video strip is post-processed by using the ALF parameter and the SA0 parameter.

The syntax of the corresponding video stripe header is as follows:

CD

}

If( slice_type = = B )

Byte_align()

Alf_cu_control_param( )

Byte_align()

}

In this embodiment, the video stripe header includes a parameter sharing identifier, identifies whether the ALF parameter and the SA0 are stored in the same APS, and determines whether to add two APS identifiers in one video strip according to the parameter shared identifier. APS identification, a video strip can be filtered by using filters in APS or different filter banks in different APSs according to the situation, improving the flexibility and compatibility of filter parameter selection, thereby improving the processing performance of video coding. A person skilled in the art can understand that all or part of the process of implementing the above embodiment method can be completed by a computer program to instruct related hardware, and the program can be stored in a computer readable storage medium. In execution, the flow of an embodiment of the methods as described above may be included. The storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM). In association with the above method embodiments, the present invention also provides a video image filtering processing apparatus, which may be located in a terminal device, a network device, or a test device. The video image filtering processing device may be implemented by a hardware circuit or by software in cooperation with hardware. For example, referring to Figure 6, a video image filtering processing device is invoked by a processor to obtain filter parameters in video decoding. The video image filtering processing apparatus can perform various methods and processes in the above method embodiments. Referring to FIG. 7, an embodiment of a video image filtering processing apparatus includes:

The receiving unit 701 is configured to receive a video stripe coded code stream. The extracting unit 702 is configured to obtain, from the video stripe header, identifiers of the at least two APSs, where the at least two APSs are used to store at least two filter parameters, where each ASP stores at least two filter parameters. The number of APS identifiers in the video stripe header is the same as the number of the filter parameters;

a parameter obtaining unit 703, configured to respectively obtain the at least two filter parameters according to the at least two APS identifiers;

The filtering unit 704 is configured to filter the video strip by using the at least two filter parameters.

In an embodiment, the extracting unit 702 is configured to obtain an identifier of a first APS storing an ALF parameter and an identifier of a second APS for storing the SA0 parameter, where each ASP stores an ALF parameter and an SA0 parameter;

The parameter obtaining unit 703 is configured to obtain an ALF parameter and an SA0 parameter according to the first APS identifier and the second APS identifier, respectively;

The filtering unit 704 is configured to filter the video strip by using the ALF parameter and the SA0 parameter. Referring to FIG. 8, another embodiment of the video image filtering processing apparatus includes:

The receiving unit 801 is configured to receive a video stripe coded code stream;

The identifier extracting unit 802 is configured to obtain a parameter sharing identifier from the video stripe header, where the parameter sharing identifier is used to indicate whether the ALF parameter and the SA0 parameter corresponding to the video stripe are stored in the same APS, and the determining unit 803 is configured to determine The parameter sharing identifier indicates whether the ALF parameter and the SA0 parameter corresponding to the video strip are stored in different APSs;

The extracting unit 804 is configured to: when the determining unit confirms that the ALF parameter and the SA0 parameter are stored in different APSs, obtain the identifier of the first APS storing the ALF parameter and the identifier of the second APS storing the SA0 parameter; wherein each ASP stores the ALF Parameters and SA0 parameters;

a parameter obtaining unit 805, configured to obtain an ALF parameter and an SA0 parameter according to the first APS identifier and the second APS identifier, respectively;

The filtering unit 808 is configured to filter the video strip by using the ALF parameter and the SA0 parameter. In another embodiment, the video image filtering processing apparatus further includes:

The second extracting unit 806 is configured to: when the determining unit determines that the ALF parameter and the SA0 parameter are stored in the same APS, obtain a shared APS identifier from the video stripe header; wherein each ASP stores the ALF parameter and the SA0 Parameter

a second parameter obtaining unit 807, configured to obtain an ALF parameter and an SA0 parameter from the ASP corresponding to the shared APS identifier;

The filtering unit 808 is configured to filter the video strip by using the ALF parameter and the SA0 parameter.

Certainly, the unitized sub-module in this implementation is not fixed. For example, the extractable unit and the second extracting unit, the parameter obtaining unit, and the second parameter obtaining unit may respectively be the same module when implemented, and the output of the determining unit is different. Different operations are performed when judging the results.

The above is only a few embodiments of the present invention, and various changes and modifications may be made to the present invention without departing from the spirit and scope of the invention.

Claims

Claim

A video image filtering processing method, comprising: receiving a video stripe coded code stream; obtaining at least two APS identifiers from a video stripe header, the at least two APSs respectively for storing at least two Filter parameters; wherein each ASP stores at least two filter parameters, and the number of APS identifiers in the video stripe header is the same as the number of the filter parameters; respectively, according to the at least two APS identifiers Decoding at least two filter parameters; filtering the video strip by using the at least two filter parameters.

The method according to claim 1, wherein the identifiers of the at least two APSs comprise: an identifier of a first APS for storing ALF parameters and an identifier of a second APS for storing SA0 parameters; Each of the ASPs stores an ALF parameter and an SA0 parameter. Obtaining the at least two filter parameters according to the at least two APS identifiers respectively includes: obtaining an ALF parameter and an SA0 parameter according to the first APS identifier and the second APS identifier, respectively.

The method according to claim 2, further comprising: obtaining a parameter sharing identifier from the video stripe header, where the parameter sharing identifier is used to indicate whether the ALF parameter and the SA0 parameter corresponding to the video strip are stored in the same In the APS, determining that the parameter sharing identifier indicates that the ALF parameter and the SA0 parameter corresponding to the video stripe are stored in different APSs.

The method according to claim 3, further comprising: if the parameter sharing identifier indicates that the ALF parameter corresponding to the video strip and the SA0 parameter are stored in the same APS, obtained from the video strip header A shared APS identifier; wherein each ASP stores an ALF parameter and an SA0 parameter; The ALF parameter and the SAO parameter are obtained from the ASP corresponding to the shared APS identifier; and the video strip is filtered by using the ALF parameter and the SA0 parameter.

The method according to claim 2, wherein the order in which the ASP stores the ALF parameter and the SA0 parameter is the same as the ID sequence in the S l i ce header.

A video image filtering processing apparatus, comprising: a receiving unit, configured to receive a video stripe coded code stream; and an extracting unit, configured to obtain, from the video stripe packet header, an identifier of at least two APSs, where At least two APSs are respectively used to store at least two filter parameters; wherein each ASP stores at least two filter parameters, and the number of APS identifiers in the video stripe header is the same as the number of the filter parameters; And an obtaining unit, configured to respectively obtain the at least two filter parameters according to the at least two APS identifiers; and a filtering unit, configured to perform filtering processing on the video strips by using the at least two filter parameters.

The device according to claim 6, wherein the extracting unit is configured to obtain an identifier of a first APS storing an ALF parameter and an identifier of a second APS for storing an SA0 parameter; wherein, each ASP The ALF parameter and the SA0 parameter are stored; the parameter obtaining unit is configured to obtain the ALF parameter and the SA0 parameter according to the first APS identifier and the second APS identifier respectively; the filtering unit is configured to use the ALF parameter and the SA0 parameter to the video strip The band is filtered.

The device according to claim 7, further comprising: an identifier extracting unit, configured to obtain a parameter sharing identifier from the video stripe header, where the parameter sharing identifier is used to indicate an ALF parameter corresponding to the video stripe Whether the SA0 parameter is stored in the same APS; the determining unit is configured to determine whether the parameter shared identifier indicates that the ALF parameter and the SA0 parameter corresponding to the video stripe are stored in different APSs; and the determining unit confirms that the ALF parameter and the SA0 parameter are stored in Do not When the same as APS, the processing function of the extraction unit is started.

The device according to claim 8, further comprising: a second extracting unit, configured to: when the determining unit determines that the ALF parameter and the SA0 parameter are stored in the same APS, from the video strip header Obtaining a shared APS identifier, where each ASP stores an ALF parameter and an SA0 parameter; a second extracting unit is configured to obtain an ALF parameter and an SA0 parameter from the ASP corresponding to the shared APS identifier; wherein, the filtering unit is used by The video strip is filtered by using the ALF parameter and the SA0 parameter.