1、 Copyright 2010 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 3 Barker Avenue., White Plains, NY 10601 (914) 761-1100 Approved July 21, 2010 Table of Contents Page Foreword . 2 Intellectual Property 2 Introduction 2 1 Scope . 3 2 Conformance Notation . 3 3 Normative References . 3 4 Desc
2、ription of Materials 4 5 File Formats . 4 6 Reference Decoder Software . 5 7 Sample VC-2 Stream Generator 6 8 Test VC-2 Streams . 6 9 Conformance Testing Procedure . 7 Annex A Coding Parameters File (Normative) . 9 Annex B Image File Format Specifications (Normative) 16 Annex C VC-2 Test Streams (In
3、formative) 18 Annex D Bibliography (Informative) . 31 Page 1 of 31 pages SMPTE RP 2042-3:2010 SMPTE RECOMMENDED PRACTICE VC-2 Conformance Specification SMPTE RP 2042-3:2010 Page 2 of 31 pages Foreword SMPTE (the Society of Motion Picture and Television Engineers) is an internationally-recognized sta
4、ndards developing organization. Headquartered and incorporated in the United States of America, SMPTE has members in over 80 countries on six continents. SMPTEs Engineering Documents, including Standards, Recommended Practices, and Engineering Guidelines, are prepared by SMPTEs Technology Committees
5、. Participation in these Committees is open to all with a bona fide interest in their work. SMPTE cooperates closely with other standards-developing organizations, including ISO, IEC and ITU. SMPTE Engineering Documents are drafted in accordance with the rules given in Part XIII of its Administrativ
6、e Practices. SMPTE Recommended Practice RP 2042-3 was prepared by Technology Committee 10E. Intellectual Property At the time of publication no notice had been received by SMPTE claiming patent rights essential to the implementation of this Standard. However, attention is drawn to the possibility th
7、at some of the elements of this document may be the subject of patent rights. SMPTE shall not be held responsible for identifying any or all such patent rights. Introduction This section is entirely informative and does not form an integral part of this document. VC-2 is a wavelet-based, intra-frame
8、 video compression system aimed at professional applications that provides efficient coding at many resolutions including various flavors of CIF, SDTV and HDTV. The VC-2 standard defines a bit-stream syntax and a reference decoder specification. To aid the creation of new VC-2 streams, this recommen
9、ded practice also provides details for the operation of a sample VC-2 stream generator. This recommended practice includes a list of VC-2 compliant streams that can be used to test various aspects of VC-2 decoder compliance. This recommended practice also includes a reference decoder for comparison-
10、testing of decoder implementations. The reference decoder may also be used to establish the compliance of arbitrary streams. SMPTE RP 2042-3:2010 Page 3 of 31 pages 1 Scope The VC-2 video compression standard is an intra-frame video compression system defined through the VC-2 stream syntax, entropy
11、coding, a coefficient unpacking process and a picture decoding process. The decoder operations are defined by means of a mixture of pseudo-code and mathematical operations. This recommended practice defines the materials, procedures, and criteria for verifying conformance of SMPTE VC-2 video decoder
12、s. The documents that form this specification include this document, a register of test streams, a sample VC-2 stream generator and a reference decoder. The reference decoder and the sample stream generator are both software written in the C+ programming language and capable of being compiled to exe
13、cutable code on a variety of computer platforms. The reference decoder can be used to verify conformance of VC-2 decoder implementations against a register of test streams, and the conformance of arbitrary streams to the VC-2 specification. This conformance practice defines both the format for the r
14、egister of test streams and the lists of test streams. 2 Conformance Notation Normative text is text that describes elements of the design that are indispensable or contains the conformance language keywords: “shall“, “should“, or “may“. Informative text is text that is potentially helpful to the us
15、er, but not indispensable, and can be removed, changed, or added editorially without affecting interoperability. Informative text does not contain any conformance keywords. All text in this document is, by default, normative, except: the Introduction, any section explicitly labeled as “Informative“
16、or individual paragraphs that start with “Note:” The keywords “shall“ and “shall not“ indicate requirements strictly to be followed in order to conform to the document and from which no deviation is permitted. The keywords, “should“ and “should not“ indicate that, among several possibilities, one is
17、 recommended as particularly suitable, without mentioning or excluding others; or that a certain course of action is preferred but not necessarily required; or that (in the negative form) a certain possibility or course of action is deprecated but not prohibited. The keywords “may“ and “need not“ in
18、dicate courses of action permissible within the limits of the document. The keyword “reserved” indicates a provision that is not defined at this time, shall not be used, and may be defined in the future. The keyword “forbidden” indicates “reserved” and in addition indicates that the provision will n
19、ever be defined in the future. A conformant implementation according to this document is one that includes all mandatory provisions (“shall“) and, if implemented, all recommended provisions (“should“) as described. A conformant implementation need not implement optional provisions (“may“) and need n
20、ot implement them as described. 3 Normative Reference Normative references are external documents referenced in normative text that are indispensable to the user. Bibliographic references are references made in informative text or are those otherwise not indispensable to the user. The following stan
21、dards contain provisions which, through reference in this text, constitute provisions of this recommended practice. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this recommended practice are encouraged to inv
22、estigate the possibility of applying the most recent edition of the standards indicated below. SMPTE RP 2042-3:2010 Page 4 of 31 pages SMPTE ST 2042-1:2009, VC2 Video Compression ISO/IEC 646:1991, Information Technology ISO 7-Bit Coded Character Set for Information Interchange 4 Description of Mater
23、ials The VC-2 conformance specification shall comprise the following components: 1. VC-2 encoded video Files, 2. Reference decoder software, 3. Sample VC-2 stream generator software, and 4. Procedures for testing VC-2 streams and the reference decoder. These components of the conformance specificati
24、on shall be as defined in the following sections. 5 File Formats This section defines the file formats used by this conformance specification. The specification defines two file formats: the file format for the storage of the coding parameters, and the file format for the storage of uncompressed vid
25、eo data. The data pertaining to each frame in a VC-2 stream shall be stored as separate files to simplify data management. A file belonging to a VC-2 stream basename shall have a filename of the form: basename-frame_number.extension where frame_number shall be the frame number in the VC-2 stream, an
26、d extension shall be a defined extension name that identifies the file storage format. The base name may be null, in which case the file name would be of the form frame_number.extension. 5.1 Coding Parameters File Format All coding parameters for a given frame number shall be stored in a file whose
27、format is defined as per Annex A. The extension part of the filename is recommended to end with “.cparams“. Note: The extension name is not required by the reference software. 5.2 Video Data File Format The video data file format shall be used to store uncompressed video data. Interlaced frames shal
28、l be stored in a pseudo-progressive manner, i.e., fields shall be interleaved such that a frame comprising two fields with no intermediate motion shall appear indistinguishable from a progressive frame. The color difference format used for each frame shall be either 4:4:4, 4:2:2 or 4:2:0. Each frame
29、 of Y, C1, C2 (as per the color model of Section 6.1 of the VC-2 specification) image data shall be stored as raw video data in a headerless planar format. SMPTE RP 2042-3:2010 Page 5 of 31 pages Data shall be serialized by raster scanning each component separately for each frame (i.e. a frame of Y,
30、 followed by a frame of C1, then a frame of C2). Each sample of video data shall be stored as a 16 bit Big-Endian word, MSB justified and zero-padded. For example, an 8 bit sample of value 0x35, would be stored in a 16 bit word as 0x3500. The extension part of the filename shall be used by the refer
31、ence software to determine the desired input/output format. The extension value shall be the FOURCCode value that correctly represents the color difference format as defined in the table below: Color difference Format FOURCCode 4:4:4 16P4 4:2:2 16P2 4:2:0 16P0 Annex C illustrates the storage format
32、for FOURCCode values 16P4, 16P2 and 16P0. In this practice, required components of the command line application wrap the component with the angle bracket symbols and optional components of the command line application wrap the component with the square bracket symbols . 6 Reference Decoder Software
33、The reference decoder shall be used for testing VC-2 stream conformance and shall implement the decoding processes defined in SMPTE ST 2042-1 VC-2. The reference decoder, in the form of platform independent C+ source code and associated documentation (instructions for building, installing and runnin
34、g the software), is available at http:/store.smpte.org. The decoder is a command line application that shall have the following invocation format: vc2decoder codingparams where: inputstream is the VC-2 stream filename to decode. outputvideo is the base of the filename to be used for storing decoded
35、output video frames. Note: The actual name of the output file will comprise the base name concatenated with a frame number plus an appropriate file extension codingparams is an optional base file specification, as per annex A, to be used for storage of the coding parameters associated with each vide
36、o frame as determined from the input stream. If this argument is not specified, no coding parameters files shall be produced. Note: The actual name of the file generated, if any, will comprise the base file name concatenated with a frame number plus “cparams” as a file extension SMPTE RP 2042-3:2010
37、 Page 6 of 31 pages The decoder decoding the input VC-2 stream, shall produce one video frame and coding parameters file for each frame decoded. The frame number for each output file shall start with frame number of the first file. The arguments outputvideo and codingparams shall use identical frame
38、 numbers. Note: There is no implicit relationship between the output frame numbers and the stream parameter, picture_number. The reference decoder shall handle multiple VC-2 sequences within a VC-2 stream by storing all frames from each sequence as presented in the VC-2 stream. The output frame numb
39、ers shall not be reset between sequences within a decoded VC-2 stream. 7 Sample VC-2 Stream Generator The sample VC-2 stream generator may be used for the creation of VC-2 streams. The sample VC-2 stream generator provided with this conformance specification provides compliant VC-2 streams that may
40、be used by VC-2 decoders for testing purposes but this generator does not represent a full implementation of a VC-2 encoder. The sample VC-2 stream generator, in the form of platform independent C+ source code and associated documentation (instructions for installing, building and running the softwa
41、re), is available at http:/store.smpte.org. The sample VC-2 stream generator is a command line application that shall have the following invocation format: vc2streamgen , where: shall be the base of the filename, as per Section 4, to be used for input video frames, shall be the base of the filename,
42、 as per Section 8, providing the coding parameters associated with each input video frame and shall be the required filename of the output VC-2 stream. The sample stream generator encodes the input video and coding parameters using one video and one coding parameters file per frame to produce a VC-2
43、 output stream. The frame number shall start from zero for both types of input file. Note: There is no implicit relation between the output frame numbers and the stream parameter picture_number since the picture_number value is determined from the coding parameters file. Multiple VC-2 sequences may
44、be encoded with a VC-2 stream by varying any value in the sequence parameter section in the relevant coding parameters file where the new sequence is desired. It is not permitted to change the sequence parameter section and not set “signalled: true“ on the encoded frame with the first change. 8 Test
45、 VC-2 Streams The register of VC-2 streams to be used for testing target decoder conformance is identified in Annex C. The set of test VC-2 streams is comprehensive but not intended to represent every possible combination of encoding parameters and tools specified in SMPTE ST 2042-1. SMPTE RP 2042-3
46、:2010 Page 7 of 31 pages 9 Conformance Testing Procedure The following sub-sections define the normative tests for verifying conformance of a candidate VC-2 stream and decoder to SMPTE ST 2042-1, and provide an informative description of how an encoder implementation can be tested with the conforman
47、ce tools provided. 9.1 Conformance Testing of A Candidate VC-2 Stream Bit stream testing is a process intended to verify that a candidate bit stream is a valid VC-2 stream in accordance to SMPTE ST 2042-1. A candidate bit stream shall be deemed a valid VC-2 stream if no fatal errors occur in the dec
48、oding of the bit stream with the reference decoder (Section 6). Note: The video files output by the reference decoder do not form part of this test, however they can be used to check that the stream decompresses as intended. If the video output is different from that intended, the encoder implementa
49、tion can be tested according to the procedure described in Section 9.3. 9.2 Conformance Testing of A Candidate Decoder Decoder testing is a process intended to verify that a candidate decoder implementation conforms to the decoding process as specified in SMPTE ST 2042-1. Decoder testing uses the register of test VC-2 streams (Section 8). It shall be noted that: - A candidate decoder need not support all possible profiles and levels. - Failure of any test is sufficient to identify the candidate decoder as non-c
