SMPTE RP 2077:xxxx

Revision of EG 2077:yyyy Amendment #z

WD Recommended Practice

Full-Range Image Mapping

Page 1 of 7 pages

AG04-1-2016-SMPTE-ST-RP-Template-2016-08-17.docx

Warning

This document is an unpublished, confidential work under development and shall not be referred to as a SMPTE Standard, Recommended Practice, or Engineering Guideline. It is distributed for review and comment; distribution does not constitute publication. Recipients of this document are strongly encouraged to submit, with their comments, notification of any relevant patent rights of which they are aware and to provide supporting documentation.

Table of Contents

1	Scope	2

2	Conformance Notation	2

3	Normative References	3

4	Terms and Definitions	3

4.1	Super Long Term	4

4.2	Full-Range Image	4

5	Section Title	4

5.1	General	4

5.2	Subject Matter	4

Annex A	Mapping to and from a 10-bit Interface that Relies upon Protected Code Values (informative)	5

A.1	Clause 1	5

A.2	Clause 2	5

Annex B	XML Schema (informative)	6

Bibliography (informative)	7

Foreword

SMPTE (the Society of Motion Picture and Television Engineers) is an internationally-recognized standards developing organization. Headquartered and incorporated in the United States of America, SMPTE has members in over 80 countries on six continents. SMPTE’s Engineering Documents, including Standards, Recommended Practices, and Engineering Guidelines, are prepared by SMPTE’s Technology Committees. 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 its Standards Operations Manual. This SMPTE Engineering Document 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 Engineering Document. However, attention is drawn to the possibility that 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 Engineering Document.

Each pixel in a digital image is commonly encoded as a triplet of n-bit binary words – see, for instance, […]

Figure 1. Full-Range Image Mapping over an Interface that Rely upon Protected Code Values.

Scope

This Recommended Practice defines mappings of full […]

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 user, 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" 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 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" 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 the 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 ("should") 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 authoritative definition; Tables shall be next; then formal languages; then figures; and then any other language forms.

Normative References

The following standards contain provisions which, through reference in this text, constitute provisions of this engineering document. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this engineering document are encouraged to investigate the possibility of applying the most recent edition of the standards indicated below.

SMPTE ST 274:2008, 1920 x 1080 Image Sample Structure, Digital Representation and Digital Timing Reference Sequences for Multiple Picture Rates

Recommendation ITU-R BT.709-5, Parameter values for the HDTV standards for production and international programme exchanges

Terms and Definitions

For the purposes of this document, the following terms and definitions apply.

Super Long Term

SLT

This is the definition for the Super Long Term.

Full-Range Image

A full-range image consists of a collection of pixels, each being quantized using a triplet of n-bit unsigned integer words.

Section Title

General

The following shall apply when mapping a full-range image to a format or interface that (i) uses triplets of the same bit length, (ii) uses the same black and white reference triplets and (iii) defines protected code values that cannot be used so that only code values in the range [CVLOW, CVHIGH] are permitted.

: CVFULL → CVP = clamp(CVLOW, CVHIGH, CVFULL) ,	(1)

where

clamp(a, b, x) =	x, if x [a, b]
a if x < a
b if x > b

NOTE 1	This is an informative note about symbol Foo.

NOTE 2	No slopes, curves, knee or shoulder are specified at the top and bottom of the mapping interval.

Subject Matter

The following applies when mapping a full-range image to a format or interface that uses narrow-range images of the same bit length n.

The function ("map from full-range to narrow-range") shall map a code value CVFULL from a full-range image to a narrow-range code value CVN on the interface or format according to:

: CVFULL → CVN = floor ( 0.5 + CVFULL / (2n -1) (RWHITE – RBLACK) + RBLACK),	(2)

where floor(x) is equal to the largest integer not greater than x.

Mapping to and from a 10-bit Interface that Relies upon Protected Code Values (informative)

Clause 1

The following illustrates the mapping of a 10-bit full-range image to and from a 10-bit interface that relies upon protected code values [0, 3] [1020,1023], using the and mappings, respectively.

The following are sub-points:

sub-point 1

sub-point 2

EXAMPLE	This is an example.

Clause 2

The same protected code values are, for instance, used by the digital interface specified in SMPTE ST 292-1.

Table B.1. Mapping code values from a full-range image (CVFULL) to a 10-bit interface (CVP) that rely upon protected code values.

CVFULL	CVP
0	4
1	4
2	4
3	4
4	4
5	5
⁞	⁞
127	127
128	128
⁞	⁞
1018	1018
1019	1019
1020	1019
1021	1019
1022	1019
1023	1019

XML Schema (informative)

This specification is accompanied by the following element, which is an XML schema document as specified in XML Schema Part 1: Structures.

st2067-100a-2014.xsd

This element collects the XML schema definitions defined in this specification. It is informative and, in case of conflict, this specification takes precedence.

Bibliography (informative)

SMPTE RP 291-2:2013, Ancillary Data Space use - 4:2:2 SDTV and HDTV component systems and 4:2:2 2048 x 1080 Production Image formats