Patent ID: 7203239
Filing Date: 2007-04-10
Classification: H04N

Abstract:
1. A computer system comprising: means for receiving encoded data of a video signal containing a variable length code generated by encoding transform coefficients obtained by orthogonal transformation of the video signal by using code words decodable in both a forward direction and a backward direction; means for detecting a sync section of the encoded data; means for decoding the encoded data in the forward direction in a predetermined sync section detected by the sync section detection unit; means for decoding the encoded data in the backward direction in the detected sync section; and means for determining a final decode result from decode results obtained by the decoding means in the forward direction and the decoding means in the backward direction, wherein each of the decoding means in the forward direction and the decoding means in the backward direction includes means for detecting an error in the encoded data, and the determining means includes means for determining a decode value by using an error detection position in the encoded data in units of bits and an error detection position in the decoded data in units of syntax, which are detected by the decoding means in the forward direction and indicate an error position in the encoded data, and an error detection position in the encoded data in units of bits and an error detection position in units of syntax, which are detected by the decoding means in the backward direction and indicate an error position in the encoded data wherein when an error is detected in the encoded data in the sync section, the determining means includes means for discarding part or all of encoded data composed of macroblock transform coefficients having undergone intraframe encoding within a macroblock in which no error has been detected.