DocumentCode :
2405001
Title :
Encoding DCT coefficients in H.263 based on rate-distortion measurement
Author :
Pao, I-Ming ; Ting Sun, Ming
Author_Institution :
Dept. of Electr. Eng., Washington Univ., Seattle, WA, USA
Volume :
2
fYear :
1999
fDate :
1999
Firstpage :
643
Abstract :
We propose a rate-distortion optimization algorithm which adjusts the magnitudes of the quantized DCT coefficients to achieve better video quality under a bit-rate constraint. The limited quantizer selections and the predetermined run-length code-word tables in the video standards are not optimal for all video sequences. Better performance can be achieved by adjusting the level of the quantized DCT coefficients, which minimizes the distortion subject to the rate constraint. After the DCT coefficients have been calculated, we select the quantization parameter (QP) and adjust the levels of the coefficients based on the rate-distortion measurement. The bit-streams thus generated by the algorithm conform to the standards. We present simulation results which show that the algorithm can achieve improvement compared to H.263+TMN8, at the same bit-rate
Keywords :
discrete cosine transforms; quantisation (signal); video coding; DCT coefficients; H.263; TMN8; optimization algorithm; quantization parameter; rate distortion measurement; video encoding; Discrete cosine transforms; Distortion measurement; Encoding; Image coding; Image reconstruction; Lagrangian functions; Quadratic programming; Quantization; Rate-distortion; Video compression;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Circuits and Systems, 1999. 42nd Midwest Symposium on
Conference_Location :
Las Cruces, NM
Print_ISBN :
0-7803-5491-5
Type :
conf
DOI :
10.1109/MWSCAS.1999.867720
Filename :
867720
Link To Document :
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