Patent ID: 7346108

Claim:
An encoded-data converting apparatus for use with image data comprising: a) encoded-data input means for inputting first encoded data encoded with a first encoding; b) header extracting means for extracting first header information from the first encoded data; c) header generating means for generating second header information for a second encoding from the first header information; d) conversion setting means for setting-up variable-length-code conversion based on both a predetermined parameter for use in the second encoding and an encoding parameter used in the first encoding; e) frame-data extracting means for extracting encoded data in one frame from the first encoded data; f) variable-length-code converting means for converting a variable length code in the encoded data in accordance with the variable-length-code conversion set-up by said conversion setting means; g) DC-component converting means for decoding DC components in the encoded data in the frame into quantized values and using the quantized values to perform predictive encoding based on the second encoding; and h) encoded-data output means for shaping the second header information and outputs of said variable-length-code converting means, and said DC-component converting means into data, and outputting the data as data encoded by the second encoding.