An Efficient Requantization for Transcoding of MPEG Video

In this paper, we propose an efficient transcoding of MPEG video. Transcoding is the process of converting a compressed video format to another different compressed video format. We propose an simple and efficient transcoding by requantization in which MPEG coded video at high bit-rate is converted into MPEG bitstream at lower bit-rate. To reduce a image quality degradation, we use HVS(Human Visual System) that is the effect that visibility of noise is less in high activity regions than in low activity regions. By using the effect, the part of image in high activity region is coarsely quantized without seriously degrading the image quality. Experimental results show that the proposed method can provide good performance.