A Joint Content Adaptive Rate-Quantization Model and Region of Interest Intra Coding of H.264/AVC

• Main Authors: Hui-chun Hsu, 許惠君
• Other Authors: Po-chyi Su
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/87679713109634436450

碩士 === 國立中央大學 === 資訊工程研究所 === 99 === This thesis presents a joint content adaptive rate-quantization model and region of interest intra coding of H.264/AVC. The rate control of video coding is an important issue and the intra coding plays a very crucial role. Inappropriate assignment of bitrates in intra coding will deteriorate the overall coding performance. We will first present a more accurate content adaptive Rate-Quantization (R-Q) model, by which we can obtain the relationship between the Quantization Parameter (QP) of a macroblock and the block complexity. Given a target bit-rate, we can thus assign a more suitable QP for a frame. In addition, since our model is built on blocks, or more specifically macroblocks, Region of Interest (ROI) coding can also be achieved. More bits can be assigned to the ROI by using a lower quantization parameter (QP) so that the perceptual quality can be maintained within the limited bit-rate. Our macorblock-level R-Q model, compared with the traditional frame-level RQ model, is more flexible and can achieve the target bit rate more accurately.