This paper presents an improved rate control method for H.264. First, the scene changes are detected by the average absolute difference of the brightness histograms between the adjacent frames. Then, the bit allocatio...This paper presents an improved rate control method for H.264. First, the scene changes are detected by the average absolute difference of the brightness histograms between the adjacent frames. Then, the bit allocation and quantization parameters are adjusted, using a certain threshold. In addition, the calculation of the mean absolute difference （MAD） is modified in an alternative way, which makes the rate distortion optimization （RDO） more accurate. Extensive simulation results show that the proposed method, compared with G012, can improve the average peak signal-to-noise ratio （PSNR） and moderate the image quality.展开更多
The bit number allocation strategy of TM5 may cause the coding quality loss and buffer overflow at scene changes, therefore a new algorithm on MPEG2 target bit number allocation is proposed in this paper. Here the ...The bit number allocation strategy of TM5 may cause the coding quality loss and buffer overflow at scene changes, therefore a new algorithm on MPEG2 target bit number allocation is proposed in this paper. Here the influence of scene changes on coding quality is analyzed and an approach to improve the coding performance at scene changes is presented to avoid sharp quality loss of scene change frames. Simulation indicates that this algorithm provides a promising coding quality at scene changes.展开更多
基金Supported by the National Natural Science Foundation of China (60372057)
文摘This paper presents an improved rate control method for H.264. First, the scene changes are detected by the average absolute difference of the brightness histograms between the adjacent frames. Then, the bit allocation and quantization parameters are adjusted, using a certain threshold. In addition, the calculation of the mean absolute difference （MAD） is modified in an alternative way, which makes the rate distortion optimization （RDO） more accurate. Extensive simulation results show that the proposed method, compared with G012, can improve the average peak signal-to-noise ratio （PSNR） and moderate the image quality.
文摘The bit number allocation strategy of TM5 may cause the coding quality loss and buffer overflow at scene changes, therefore a new algorithm on MPEG2 target bit number allocation is proposed in this paper. Here the influence of scene changes on coding quality is analyzed and an approach to improve the coding performance at scene changes is presented to avoid sharp quality loss of scene change frames. Simulation indicates that this algorithm provides a promising coding quality at scene changes.
