1、 Copyright 2012 by THE SOCIETY OF MOTION PICTURE AND TELEVISION ENGINEERS 3 Barker Avenue, White Plains, NY 10601 (914) 761-1100 Approved January 30, 2012 Table of Contents Page Foreword . 2 Intellectual Property 2 Introduction . 2 1 Scope . 5 2 Conformance Notation . 5 3 Normative References . 5 4
2、Filtering Overview 6 5 Filtering Coefficients for 4:2:2 and 4:2:0 Inter-format Sampling System . 6 5.1 Definitions 6 5.2 Filter Coefficients . 6 Annex A Bibliography (Informative) . 11 Page 1 of 11 pages SMPTE RECOMMENDED PRACTICE 4:2:2 / 4:2:0 Format Conversion Minimizing Color Difference Signal De
3、gradation in Concatenated Operations Filtering SMPTE RP 2050-1:2012SMPTE RP 2050-1:2012 Page 2 of 11 pages Foreword SMPTE (the Society of Motion Picture and Television Engineers) is an internationally-recognized standards developing organization. Headquartered and incorporated in the United States o
4、f 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. Participation in these Committees is open to all with a bona fide interest in their
5、 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 Administrative Practices. SMPTE RP 2050-1 was prepared by Technology Committee 32NF. Intellectual
6、Property SMPTE draws attention to the fact that it is claimed that compliance with this Standard may involve the use of one or more patents or other intellectual property rights (collectively, “IPR“). The Society takes no position concerning the evidence, validity, or scope of this IPR. Each holder
7、of claimed IPR has assured the Society that it is willing to License all IPR it owns, and any third party IPR it has the right to sublicense, that is essential to the implementation of this Standard to those (Members and non-Members alike) desiring to implement this Standard under reasonable terms a
8、nd conditions, demonstrably free of discrimination. Each holder of claimed IPR has filed a statement to such effect with SMPTE. Information may be obtained from the Director, Standards or that a certain course of action is preferred but not necessarily required; or that (in the negative form) a cert
9、ain possibility or course of action is deprecated but not prohibited. The keywords “may“ and “need not“ indicate 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 th
10、e future. The keyword “forbidden” indicates “reserved” and in addition indicates that the provision will never 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 (“sh
11、ould“) as described. A conformant implementation need not implement optional provisions (“may“) and need not implement them as described. Unless otherwise specified, the order of precedence of the types of normative information in this document shall be as follows: Normative prose shall be the autho
12、ritative definition; Tables shall be next; followed by formal languages; then figures; and then any other language forms. 3 Normative References The following standards contain provisions which, through reference in this text, constitute provisions of this recommended practice. At the time of public
13、ation, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this recommended practice are encouraged to investigate the possibility of applying the most recent edition of the standards indicated below. No normative references are specified for
14、implementation of this document. SMPTE RP 2050-1:2012 Page 6 of 11 pages 4 Filtering Overview Figure 5 Overview of Filtering Figure 5 shows the overview of the filtering defined in this document. When a 4:2:0 video decoder and encoder are connected via a serial interface, 4:2:0 data is decoded and t
15、he data is converted to 4:2:2 by up-sampling the color difference component, and then the 4:2:2 video data is mapped onto a serial interface. In the 4:2:0 video encoder, the 4:2:2 video data from the serial interface is converted to 4:2:0 video data by down-sampling the color difference component. T
16、his document defines filter coefficient sets for 4:2:0/4:2:2 up-sampling and filter coefficient sets for 4:2:2/4:2:0 down-sampling, to provide minimally degraded 4:2:0 color difference signals in concatenated operations. Note: An example implementation of the filter sets defined in this document is
17、described in SMPTE EG 2050-2. 5 Filtering Coefficients for 4:2:2 and 4:2:0 Inter-format Sampling System 5.1 Definitions The following nomenclature is used in this document. F0-3F4: Filter coefficients for conversion from 4:2:2 to 4:2:0. F1e-1F1e2, F1o-1F1o2: Filter coefficients from 4:2:0 to 4:2:2.
18、Divisor: A value equal to the sum of the filter coefficients to maintain unity gain through the filter. Even Line: even numbered active line of a progressive image, and even numbered active line in the first and second field of an interlaced image. For progressive images, the line number zero corres
19、ponds to the first active line of the progressive image. For the first field of an interlaced image, the line number zero corresponds to the first active line. For the second field of an interlaced image, the line number zero corresponds to the first active line. Odd Line: odd numbered active line o
20、f a progressive image, and odd numbered active line in the first and second field of an interlaced image. 5.2 Filter Coefficients This section defines the filter coefficients for down-sampling from 4:2:2 to 4:2:0 and up-sampling from 4:2:0 to 4:2:2. 5.2.1 Progressive Images Figure 6 shows a mapping
21、of 4:2:2 and 4:2:0 samples for the filter coefficients of progressive image format. SMPTE RP 2050-1:2012 Page 7 of 11 pages Luminance sample positionColor difference sample position in 4:2:2 formatColor difference sample position in 4:2:0 formatFigure 6 Mapping of 4:2:2 and 4:2:0 samples for the pro
22、gressive image format For the conversion from 4:2:2 to 4:2:0 of a progressive image, the filter coefficients defined in Table 1 shall be applied to the down-sampling procedure. The divisor shall be 1024. Table 1 Progressive image format filter coefficients for 4:2:2 / 4:2:0 conversion Position F0-3
23、F0-2 F0-1 F00 F01 F02 F03 F04 Coefficients -3 -19 34 500 500 34 -19 -3 For the conversion from 4:2:0 to 4:2:2 of a progressive image, the filter coefficients defined in Table 2 and Table 3 shall be applied to the up-sampling procedure. The divisor shall be 1024. Table 2 Progressive image format filt
24、er Coefficients for 4:2:0 / 4:2:2 conversion of Even Lines Position F1e-2 F1e-1 F1e0 F1e1 Coefficients 19 103 1037 -135 Table 3 Progressive image format Filter Coefficients for 4:2:0 / 4:2:2 conversion of Odd Lines Position F1o-1 F1o0 F1o1 F1o2 Coefficients -135 1037 103 19 SMPTE RP 2050-1:2012 Page
25、 8 of 11 pages 5.2.2 Interlaced Images 5.2.2.1 First field of Interlaced Images Figure 7 shows a mapping of 4:2:2 and 4:2:0 samples for the filter coefficients of the first field in the interlace image format. Luminance sample positionColor difference sample position in 4:2:2 formatColor difference
26、sample position in 4:2:0 formatFigure 7 Mapping of 4:2:2 and 4:2:0 samples for the first field of interlace image format For the conversion from 4:2:2 to 4:2:0 of the first field an interlaced image, the filter coefficients defined in Table 4 shall be applied to the down-sampling procedure. The divi
27、sor shall be 1024. Table 4 Interlaced image format filter coefficients for 4:2:2 / 4:2:0 conversion for the first field Position F0-3 F0-2 F0-1 F00 F01 F02 F03 F04 Coefficients -8 -26 115 586 409 -48 -4 0 For the conversion from 4:2:0 to 4:2:2 of the first field of an interlaced image , the filter c
28、oefficients defined in Table 5 and Table 6 shall be applied to the up-sampling procedure. The divisor shall be 1024. SMPTE RP 2050-1:2012 Page 9 of 11 pages Table 5 Interlaced image format filter Coefficients for 4:2:0 / 4:2:2 conversion for Even Lines of the first field Position F1e-2 F1e-1 F1e0 F1
29、e1 Coefficients 24 -41 1169 -128 Table 6 Interlaced image format filter Coefficients for 4:2:0 / 4:2:2 conversion for Odd Lines of the first field Position F1o-1 F1o0 F1o1 F1o2 Coefficients -76 783 330 -13 5.2.2.2 Second Field of Interlaced Images Figure shows a mapping of 4:2:2 and 4:2:0 samples fo
30、r the filter coefficients of the first field in the interlace image format. Luminance sample positionColor difference sample position in 4:2:2 formatColor difference sample position in 4:2:0 formatFigure 8 Mapping of 4:2:2 and 4:2:0 samples for the second field of interlace image format SMPTE RP 205
31、0-1:2012 Page 10 of 11 pages For the conversion from 4:2:2 to 4:2:0 of the second field of an interlaced image, the filter coefficients defined in Table 7 shall be applied to the down-sampling procedure. The divisor shall be 1024. Table 7 Interlaced image format filter coefficients for 4:2:2 / 4:2:0
32、 conversion for the second field Position F0-3 F0-2 F0-1 F00 F01 F02 F03 F04 Coefficients 0 -4 -48 409 586 115 -26 -8 For the conversion from 4:2:0 to 4:2:2 of the second field of an interlaced image, the filter coefficients defined in Table 8 and Table 9 shall be applied to the up-sampling procedur
33、e. The divisor shall be 1024. Table 8 Interlaced image format filter Coefficients for 4:2:0 / 4:2:2 conversion for Even Lines of the second field Position F1e-2 F1e-1 F1e0 F1e1 Coefficients -13 330 783 -76 Table 9 Interlaced image format filter Coefficients for 4:2:0 / 4:2:2 conversion for Odd Lines
34、 of the second field Position F1o-1 F1o0 F1o1 F1o2 Coefficients -128 1169 -41 24 SMPTE RP 2050-1:2012 Page 11 of 11 pages Annex A Bibliography (Informative) Note: All references in this document to other SMPTE documents use the current numbering style (e.g. SMPTE ST 274:2008) although, during a tran
35、sitional phase, the document as published (printed or PDF) may bear an older designation (such as SMPTE 274M-2008). Documents with the same root number (e.g. 274) and publication year (e.g. 2008) are functionally identical. SMPTE ST 274:2008, Television 1920 1080 Image Sample Structure, Digital Repr
36、esentation and Digital Timing Reference Sequences for Multiple Picture Rates SMPTE ST 292-1:2012, 1.5 Gb/s Signal / Data Serial Interface SMPTE ST 296:2011, 1280 720 Progressive Image Sample Structure Analog and Digital Representation and Analog Interface SMPTE ST 372:2011, Dual Link 1.5 Gb/s Digita
37、l Interface for 1920 1080 and 2048 1080 Picture Formats SMPTE ST 421:2006, VC-1 Compressed Video Bitstream Format and Decoding Process Amendment 1:2007 to SMPTE ST 421:2006 Amendment 2:2011 to SMPTE ST 421:2006 SMPTE ST 424:2006, Television 3 Gb/s Signal / Data Serial Interface SMPTE EG 2050-2:2012,
38、 4:2:2 / 4:2:0 Format Conversion Minimizing Color Difference Signal Degradation in Concatenated Operations Application ISO/IEC 13818-2:2000, Information Technology Generic Coding of Moving Pictures and Associated Audio Information: Video ITU-T Recommendation H.264, Advanced Video Coding for Generic Audiovisual Services “The 4:2:2/4:2:0 perfect reconstruction filter set and its application in HD-SNG”, SMPTE Motion Imaging Journal, pp29-39, July/August 2009
