Method of MPEG-2 video variable length decoding in software
View Patent ↗A method achieves high performance MPEG-2 video variable length decoding as to improve MPEG-2 video decoding process on the whole. The method includes parsing bits, Huffman code decoding for macroblock address increment, decoding motion code, and decoding macroblocks including intra and non-intra macroblocks. This is suitable to any application that are compliant with MPEG-2 MP@ML or MP@ HL video standard. For example, in PC-DTV receiver application, with properly configured PC, one can receive DTV program in real time.
1. A method of MPEG-2 video variable length decoding in software, comprising steps of:
parsing bits using embedded assembly instructions and MMX technology;
decoding macroblock address increment by first checking the increment value one;
decoding motion code using a new designed variable length code tables including sign bit; and
decoding DCT coefficients of macroblock using said new designed variable length code tables including sign bit.
2. A method of MPEG-2 video variable length decoding in software according to claim 1 ,
wherein said parsing bits using embedded assembly instructions and MMX technology comprises steps of:
initializing a 64-bit buffer using the embedded assembly instructions;
peeking the value of certain bits from said 64-bit buffer using embedded assembly instructions;
flushing certain bits from said 64-bit buffer; and
obtaining the value of certain bits from said 64-bit buffer.
3. A method of MPEG-2 video variable length decoding in software according to claim 1 ,
wherein said decoding DCT coefficients of macroblock using the new designed variable length code tables of DCT coefficient including the sign bit comprises steps of:
clearing macroblock using MMX technology;
decoding DCT coefficients for an intra macroblock with intra vlc format;
decoding DCT coefficients for an intra macroblock with non-intra vlc format; and
decoding DCT coefficients for a non-intra macroblock.