本建议国际标准规定了一种替代块编码算法，可用于替代建议ITU-T T.800 | ISO/IEC 15444-1中规定的块编码算法。这种替代的块编码算法以略微降低的编码效率为代价，显著提高了吞吐量，同时a）允许在使用Rec.ITU？T.800 | ISO/IEC 15444-1中规定的块编码算法的码流之间进行数学上的无损转码，以及b）保留Rec.ITU-T.800 | ISO/IEC 15444-1中规定的码流语法和特征
建议ITU-T.814（2019）是ISO/IEC 15444-15:2019的通用文本，两个版本都在第一版中。

This Recommendation International Standard specifies an alternate block-coding algorithm that can be used in place of the block-coding algorithm specified in Rec. ITU-T T.800 | ISO/IEC 15444-1. This alternate block-coding algorithm offers a significant increase in throughput at the expense of slightly reduced coding efficiency, while a) allowing mathematically lossless transcoding to and from codestreams that use the block-coding algorithm specified in Rec. ITU？T T.800 | ISO/IEC 15444-1, and b) preserving codestream syntax and features specified in Rec. ITU-T T.800 | ISO/IEC 15444-1.
Recommendation ITU-T T.814 (2019) is a common text with ISO/IEC 15444-15:2019, both in their first edition.