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.