| 摘要 |
A data encoding apparatus operable to encode a plurality of data blocks produces encoded data in accordance with at least one of a selectable target data quantity or a selectable target data quality. The apparatus comprises a plurality of encoding processors at least one of the encoding processors having a parameter controller operable to determine, for each of the data blocks, a value for an encoding parameter to be used in an encoding process, which encoding parameter has an effect of influencing the quantity of encoded data produced by the encoding process and the quality of a decoded version of each data block encoded using the encoding process, the value of the parameter being determined to satisfy at least one of the target data quantity and the target data quality for each encoded data block, and an encoder operable to encode each of the data blocks in accordance with the encoding process to form encoded data blocks using the value of the encoding parameter determined for each block, and a selection processor operable, for each data block, to select one of the encoded blocks produced by each of the plurality of encoding processors in dependence upon which of the data blocks has at least one of the highest quality and the lowest data quantity. The encoding process is selected to provide either the highest decoded image quality or the lowest encoded data quantity depending on whether the compression ratio for each data block is fixed or the decoded data quality is fixed and the quantity of encoded data arranged to vary. Embodiments of the present invention find particular application for encoding video data, and for use in the Motion Picture Experts Group-IV (MPEG-IV) coding scheme. |
