ISO/IEC 23002-1:2006 信息技术 MPEG视频技术 第1部分：整倍数输出式8x8离散反余弦变换执行的准确性要求
标准编号：ISO/IEC 23002-1:2006
中文名称：信息技术 MPEG视频技术 第1部分：整倍数输出式8x8离散反余弦变换执行的准确性要求
英文名称：Information technology — MPEG video technologies — Part 1: Accuracy requirements for implementation of integer-output 8x8 inverse discrete cosine transform
发布日期：2006-12
标准范围
许多图像和视频译码相关标准包括对解码器实施整数输出8 × 8逆离散余弦变换(IDCT)的要求，以针对某个整数位B生成标称范围从-2B到(2B)-1的逆变换样本差，其中B大于或等于8。ISO/IEC 23002-1:20 06规定了在这种整数输出IDCT实现中建立足够精度的一致性要求。它旨在适用于参考建立IDCT准确度的部分或全部要求，以符合要求使用IDCT的其他标准。ISO/IEC 23002-1:20 06正文中规定的精度要求与ITU附录A中IEEE 1180-1990（现已撤回）中先前规定的精度要求基本相同-T建议。H.261，以及ITU-T Rec的附件A。H.263.在此指定这些要求以解决MPEG标准中的IEEE 1180-1990的规范性引用，并为IDCT准确度要求的规范提供改进的清晰度。先前在IEEE 1180-1990中还规定了对编码比特流帧内刷新频率的附加要求，建立了比特流一致性的要求，即每个宏块在预测画面中被编码而没有中间帧画面的132次的每个序列内至少被帧内编码一次。该附加要求未在ISO/IEC 23002-1:20 06中指定，以便将其范围限制在解码器一致性规范的域中。ISO/IEC 23002-1:20 06允许对规定的准确度要求进行修改。附录A和B中规定了参考规范可能引用的其他准确度要求。
A number of image and video coding related standards include a requirement for decoders to implement an integer-output 8x8 inverse discrete cosine transform (IDCT) for the generation of inverse-transformed sample differences with a nominal range from -2B to (2B)-1 for some integer number of bits B, where B is greater than or equal to 8. ISO/IEC 23002-1:2006 specifies conformance requirements for establishing sufficient accuracy in such an integer-output IDCT implementation. It is intended to be suitable for reference to establish partial or complete requirements for IDCT accuracy for conformance to other standards that require IDCT use.
The accuracy requirements specified in the main body of ISO/IEC 23002-1:2006 are essentially the same as those previously specified in IEEE 1180-1990 (which has since been withdrawn), in Annex A of ITU-T Rec. H.261, and in Annex A of ITU-T Rec. H.263. These requirements have been specified herein to resolve normative references to IEEE 1180-1990 in MPEG standards after its withdrawal and to provide improved clarity for the specification of IDCT accuracy requirements.
An additional requirement on encoded-bitstream intra refresh frequency was also previously specified in IEEE 1180-1990, establishing a requirement of bitstream conformance that each macroblock be intra-coded at least once within each series of 132 times that it is coded in a predicted picture without an intervening intra picture. That additional requirement is not specified in ISO/IEC 23002-1:2006, in order to confine its scope to the domain of decoder conformance specification.
Some allowances for modification of the specified accuracy requirements are made within ISO/IEC 23002-1:2006. Additional accuracy requirements that may be invoked by a referencing specification are specified in Annexes A and B.
标准预览图
