标准摘要
[中文适用范围]： 许多图像和视频编码相关标准（请参阅参考书目）包括要求解码器实现整数输出 8x8 离散余弦逆变换 (IDCT)，以生成标称范围从 –2B 到 (2B) 的逆变换样本差异–1 表示某个整数位数 B，其中 B 大于或等于 8。 ISO/IEC 23002 的这一部分规定了在此类整数输出 IDCT 实现中建立足够精度的一致性要求。 它旨在适合参考建立 IDCT 精度的部分或完整要求，以符合需要使用 IDCT 的其他标准。 ISO/IEC 23002本部分主体中规定的精度要求与之前[7]、[1]的附录A和[5]的附录A中规定的精度要求基本相同。 此处指定这些要求是为了解决 MPEG 标准撤销后对 [7] 的规范性引用，并为 IDCT 精度要求的规范提供更高的清晰度。 先前在[7]中还指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要求，即每个宏块在预测图片中编码的每个系列 132 次内至少进行一次帧内编码，而不需要进行帧内编码。 中间的内部图片。 ISO/IEC 23002 的本部分未指定该附加要求，以便将其范围限制在解码器一致性规范的范围内。 ISO/IEC 23002 的本部分允许对指定精度要求进行一些修改。 附录 A 和 B 中规定了参考规范可能引用的其他精度要求。 [外文原描述]： 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of ISO/IEC 23002-1:2006 are essentially the same as those previously specified in IEEE 1180-1990 (which has since been withdrawn), in Annex A of ITU-T Rec.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.
英文名称Information technology - MPEG video technologies - Part 1: Accuracy requirements for implementation of integer-output 8x8 inverse discrete cosine transform