1、 Recommendation ITU-R BT.1692-1(09/2009)Optimization of the quality of colourreproduction in digital televisionBT SeriesBroadcasting service(television)ii Rec. ITU-R BT.1692-1 Foreword The role of the Radiocommunication Sector is to ensure the rational, equitable, efficient and economical use of the
2、 radio-frequency spectrum by all radiocommunication services, including satellite services, and carry out studies without limit of frequency range on the basis of which Recommendations are adopted. The regulatory and policy functions of the Radiocommunication Sector are performed by World and Region
3、al Radiocommunication Conferences and Radiocommunication Assemblies supported by Study Groups. Policy on Intellectual Property Right (IPR) ITU-R policy on IPR is described in the Common Patent Policy for ITU-T/ITU-R/ISO/IEC referenced in Annex 1 of Resolution ITU-R 1. Forms to be used for the submis
4、sion of patent statements and licensing declarations by patent holders are available from http:/www.itu.int/ITU-R/go/patents/en where the Guidelines for Implementation of the Common Patent Policy for ITU-T/ITU-R/ISO/IEC and the ITU-R patent information database can also be found. Series of ITU-R Rec
5、ommendations (Also available online at http:/www.itu.int/publ/R-REC/en) Series Title BO Satellite delivery BR Recording for production, archival and play-out; film for television BS Broadcasting service (sound) BT Broadcasting service (television) F Fixed service M Mobile, radiodetermination, amateu
6、r and related satellite services P Radiowave propagation RA Radio astronomy RS Remote sensing systems S Fixed-satellite service SA Space applications and meteorology SF Frequency sharing and coordination between fixed-satellite and fixed service systems SM Spectrum management SNG Satellite news gath
7、ering TF Time signals and frequency standards emissions V Vocabulary and related subjects Note: This ITU-R Recommendation was approved in English under the procedure detailed in Resolution ITU-R 1. Electronic Publication Geneva, 2009 ITU 2009 All rights reserved. No part of this publication may be r
8、eproduced, by any means whatsoever, without written permission of ITU. Rec. ITU-R BT.1692-1 1 RECOMMENDATION ITU-R BT.1692-1 Optimization of the quality of colour reproduction in digital television (2004-2009) Scope The Recommendation specifies that technical solutions for colour-adaptative digital
9、TV systems should be based on use of colour appearance models built with consideration of the adaptation of the human visual system to viewing conditions (possibly different) at both transmitting and receiving ends of the light-to-light TV path. The ITU Radiocommunication Assembly, considering a) th
10、at in digital television the quality of colour reproduction is an important part of the overall quality of TV images and of the TV service itself; b) that it seems that in future broadcasters will continue to be interested in further optimization of colorimetric quality of digital TV images; c) that
11、 the modern level of colour science may be a basis for further development of the methods of optimization of colour reproduction quality in digital television; d) that throughout the world, digital TV system development is based on the transmission of the digital stream containing, particularly, met
12、adata with service information which may be used for the optimization of video transmission in the light-to-light complete digital TV chain. It becomes possible to optimize the quality of colour reproduction by means of TV image processing at both ends of the complete transmission chain, including v
13、iewing conditions; e) that use of colour image statistics, human colour perception properties and an appropriate colour appearance model may provide an opportunity for further improvement of image compression, and a decision should be made on the basis of the trade-off between the image quality, and
14、, particularly, colour reproduction quality and the degree of bit rate reduction; f) that the use of new methods of colour image processing and compression may lead to new possibilities of colour reproduction in digital television; g) that modern methods of the digital video coding for image present
15、ation are oriented towards either image sample coding or object-based coding. The usage of object-based presentation of video information allows significant bit-rate reduction to be achieved and its use in TV broadcasting is under study worldwide; h) that use of object-based presentation of video in
16、formation implies the possibility of differences in the conditions of capturing, production and processing of separate objects, and that in the process of programme production or in some other video processing in the TV light-to-light chain the possibility of separate object information matching sho
17、uld be provided by metadata, and this information should be brought to the common viewing conditions on transmission and/or on receiving; j) that some receivers in the future may use algorithms implementing the procedure for reaching subjectively optimal colour reproduction; 2 Rec. ITU-R BT.1692-1 k
18、) that a unique set of colorimetric parameters and related characteristics required for all future digital television systems is specified for the conventional and extended colour gamut in Recommendation ITU-R BT.1361; l) that the new methods should be backwards compatible with established digital c
19、olour transmission methods, so in future there will be two system levels: non-colour-adaptive digital TV systems; colour-adaptive digital TV systems, recommends 1 that technical solutions for colour-adaptive digital TV systems should be based on use of colour appearance models built with considerati
20、on of the adaptation of the human visual system to viewing conditions (possibly different) at both ends of the light-to-light TV path; 2 that in the case of object-based image presentation, metadata should desirably carry parameters related to the specific object capturing, processing, transmission,
21、 etc.; 3 that colour appearance models (built on a threshold or non-threshold basis) may be a part of future systems, and in this case the system becomes a colour-adaptive digital TV system; 4 that backward compatibility is necessary for colour-adaptive digital TV systems, and that the colorimetric parameters and related characteristics as described in Recommendation ITU-R BT.1361, should be used for colour-adaptive digital TV systems; 5 that in future additional viewing conditions should be recommended for viewing colour television.
