记录:ITU-T.800 | ISO/IEC 15444-1？定义了一套无损和有损压缩方法，用于编码连续色调、双电平、灰度或彩色数字静态图像。本建议|国际标准提供了三个独立创建的Rec.ITU-T.800 | ISO/IEC 15444-1软件参考实现，以帮助Rec.ITU-T.800 | ISO/IEC 15444-1的实现者测试和理解其内容。这些软件包是JASPER、JJ2000和OPENJPEG。 本建议|国际标准还提供了独立创建的Rec软件参考实现。 ITU-T.814 | ISO/IEC 15444-15，其中规定了一种高通量（HT）块编码算法，可用于代替Rec.ITU-T.800 | ISO/IEC 15444-1的块编码算法，以帮助Rec.ITU-T.814 | ISO/IEC 15444-15的实施者测试和理解其内容。包裹是TT。 本建议|国际标准还提供了一个独立创建的软件参考实现，用于解析建议ITU-T T.800 | ISO/IEC 15444-1中规定的JP2文件格式和建议ITU-T T.814 | ISO/IEC 15444中规定的JPH文件格式- 该软件包是码流解析器。 本建议|国际标准未定义JPEG 2000图像编码系统的任何附加部分。 J2K参考软件的每个版本都包含源代码，可以通过编译来提供以下功能: –将选定的、广泛可用的图像格式转换为JPEG 2000码流。 –将选定的、广泛可用的图像格式转换为JP2文件格式。 –选择范围广泛的JPEG 2000编码选项（如各参考软件中所述）。 –将JPEG 2000码流解码为一系列选定的广泛可用的图像格式。 –处理JP2文件以提取JPEG 2000码流，用于解码和转换为一系列选定的广泛可用的图像格式。 –能够从JP2文件中提取元数据，包括图像标题框和颜色空间的内容。 –对JP2文件进行解码，该文件使用基于三分量矩阵的受限ICC方法形式来指定颜色空间，并将解码图像数据转换为sRGB颜色空间以供显示，包括对所有解码分量进行有限的上采样，以达到相同的分辨率。 –对JP2文件进行解码，该文件使用受限ICC方法的单色形式来指定颜色空间，并将解码后的图像数据转换为JP2文件格式中定义的基于sRGB的灰度空间。 –对使用sYCC颜色空间的JP2文件进行解码，并将解码后的图像数据转换为用于显示的sRGB颜色空间，包括对所有解码组件进行上采样，以获得相同的分辨率。 –？一些辅助评估和测试的附加工具。 TT HTJ2K参考软件包含源代码，可对其进行编译以提供以下功能: –？将HTJ2K码流解码为一系列选定的广泛可用的图像格式。 码流解析器参考软件包含源代码，可以提供以下功能: –解析JP2文件格式； –解析JPH文件格式。 参考软件旨在用作JPEG 2000其他实现的测试和验证工具，并帮助理解Rec.ITU-T T.800 | ISO/IEC 15444-1和Rec.ITU-T T.814 | ISO/IEC 15444-15。

Rec. ITU-T T.800 | ISO/IEC 15444-1？defines a set of lossless and lossy compression methods for coding continuous-tone, bi-level, greyscale or colour digital still images. This Recommendation | International Standard provides three independently created software reference implementations of Rec. ITU-T T.800 | ISO/IEC 15444-1, in order to assist implementers of Rec. ITU-T T.800 | ISO/IEC 15444-1 in testing and understanding its content. The packages are JASPER, JJ2000 and OPENJPEG. This Recommendation | International Standard also provides an independently created software reference implementation of Rec. ITU-T T.814 | ISO/IEC 15444-15, which specifies a high-throughput (HT) block coding algorithm that can be used in place of the block coding algorithm of Rec. ITU-T T.800 | ISO/IEC 15444-1, in order to assist implementers of Rec. ITU-T T.814 | ISO/IEC 15444-15 in testing and understanding its content. The package is TT. This Recommendation | International Standard additionally provides an independently created software reference implementation for parsing of a JP2 file format specified in Rec. ITU-T T.800 | ISO/IEC 15444-1 and a JPH file format specified in Rec. ITU-T T.814 | ISO/IEC 15444-15, The package is Codestream-parser. This Recommendation | International Standard does not define any additional part of the JPEG 2000 image coding system. Each version of the J2K reference software contains source code, which can be compiled to provide the following functionality: –？Transcoding from selected, widely available image formats into a JPEG 2000 codestream. –？Transcoding from selected, widely available image formats into the JP2 file format. –？Selection of a wide range of JPEG 2000 encoding options (as documented in each reference software). –？Decoding from a JPEG 2000 codestream to a range of selected widely available image formats. –？Processing of a JP2 file to extract a JPEG 2000 codestream for decoding and conversion to a range of selected widely available image formats. –？The ability to extract metadata from a JP2 file, including the contents of the Image Header box and the colour space. –？The decoding of JP2 files that use the three-component matrix-based form of the restricted ICC method for the specification of colour space and the conversion of the decoded image data to the sRGB colour space for display, including limited upsampling of all decoded components to the same resolution. –？The decoding of JP2 files that use the monochrome form of the restricted ICC method for the specification of colour space and the conversion of the decoded image data to the sRGB based greyscale space as defined within the JP2 file format. –？The decoding of JP2 files that use the sYCC colour space and the conversion of the decoded image data to the sRGB colour space for display, including upsampling of all decoded components to the same resolution. –？Some additional tools to help with evaluation and testing. The TT HTJ2K reference software contains source code, which can be compiled to provide the following functionality: –？Decoding from a HTJ2K codestream to a range of selected widely available image formats. The codestream-parser reference software contains source code, which can provide the following functionality: –？Parsing of JP2 file format; –？Parsing of JPH file format. The reference software is intended for use as a testing and validation tool for other implementations of JPEG 2000, and to help in the understanding of Rec. ITU-T T.800 | ISO/IEC 15444-1 and Rec. ITU-T T.814 | ISO/IEC 15444-15.