信息技术 - MPEG系统技术 - 第11部分:节能媒体消费（绿色元数据）

[中文适用范围]： 本文件指定了节能解码、编码、呈现和选择媒体的元数据。节能解码的元数据指定两组信息：复杂度指标（CM）元数据和解码操作减少请求（DOR-Req）元数据。解码器使用CM元数据以改变工作频率并因此降低解码器功耗。在点对点视频会议应用中，远程编码器使用DOR-Req元数据修改比特流的解码复杂度，从而减少本地解码器的功耗。节能编码的元数据指定用于解码器降低低功率编码质量损失的质量指标。节能呈现的元数据指定RGB组件统计信息和质量级别。呈现子系统根据这些统计数据调整显示参数以提供所需的品质级别（来自该元数据中提供的品质级别），从而减少功率消耗。节能媒体选择的元数据指定解码操作减少比率（DOR-Ratios）、RGB组件统计信息和质量级别。自适应流媒体会话中的客户端使用此元数据确定可用视频表示的解码器和显示节电特性，并根据给定的节电情况选择具有最佳品质的表示。 [外文原描述]： This document specifies metadata for energy-efficient decoding, encoding, presentation and selection of media. The metadata for energy-efficient decoding specifies two sets of information: complexity metrics (CM) metadata and decoding operation reduction request (DOR-Req) metadata. A decoder uses CM metadata to vary operating frequency and thus reduce decoder power consumption. In a point-to-point video conferencing application, the remote encoder uses the DOR-Req metadata to modify the decoding complexity of the bitstream and thus reduce local decoder power consumption. The metadata for energy-efficient encoding specifies a quality metric that is used by a decoder to reduce the quality loss from low-power encoding. The metadata for energy-efficient presentation specifies RGB-component statistics and quality levels. A presentation subsystem uses this metadata to reduce power by adjusting display parameters, based on the statistics, to provide a desired quality level from those provided in the metadata. The metadata for energy-efficient media selection specifies decoder operation reduction ratios (DOR-Ratios), RGB-component statistics and quality levels. The client in an adaptive streaming session uses this metadata to determine decoder and display power-saving characteristics of available video representations and to select the representation with the optimal quality for a given power-saving.