A Modified Method for Detecting All - zero DCT Coefficients Blocks before DCT and Quantization ?
نویسندگان
چکیده
A new video coding method is presented in this paper, which has been applied to the remote microscope monitoring system (RMMS). Using a criterion deduced from DCT (Discrete Cosine Transform) and quantization formulas and a criterion gotten by researching the characteristic of DCT coefficients distribution and experiment results, the method can detect all-zero AC (Alternating Current) coefficients blocks in all INTRA-blocks and all-zero DCT coefficients blocks in all motion compensation blocks before DCT and quantization. With the method, encoder can let DCT coefficients of these all-zero blocks be zeros directly instead of conducting DCT and quantization. With H.263+ encoder, simulation results show that the method can reduce the computational load significantly without video quality loss.
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