| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a transcoder and a transcoding method capable of performing recompression encoding for an image data at a low cost and a high speed, with little deterioration in the picture quality. <P>SOLUTION: The transcoder comprises a decoding portion, a re-quantization portion, and an encoding portion. The decoding portion decodes image data encoded according to a first compression encoding method, performs de-quantization, and inputs the de-quantized image data into the re-quantization portion, The re-quantization portion performs re-quantization for the image data inputted by the decoding portion, using a quantization step value for actualizing an established code amount. The decoding portion encodes the image data re-quantized by the re-quantization portion, according to a second compression encoding method. The re-quantization portion determines the quantization step value in a way to alleviate accumulation of prediction errors, taking a screen position of macro-blocks for re-quantization and the degree of reference from perimeter blocks into consideration, when re-quantization is performed for the image data (intra picture) where intra frame prediction encoding has been carried out. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
