Joint optimization method for rate-distortion based jpeg quantization table and clipping position

Abstract

The application discloses a joint optimization method of a JPEG quantization table and a truncation position based on rate distortion, relates to the technical field of JPEG coding optimization, and solves the technical problems that the joint optimization of using a quantization table and a truncation position is ignored in a JPEG compression scheme, coding efficiency is improved, and it is difficult to find an optimal quantization table and a truncation position. From the perspective of evolutionary calculation and in combination with a JPEG compression method, the application jointly optimizes a quantization table and a truncation position of the JPEG, respectively optimizes the quantization table while fixing the truncation position, optimizes the truncation position while keeping the quantization table unchanged, designs an evaluation method of fitness evaluation, and based on the rate distortion optimization method, the optimal quantization table and the truncation position can be effectively found. In the optimization process, multiple sets of quantization tables are generated, and the corresponding truncation positions are optimized. The application can more effectively compress image data and reduce redundant information, so that the coding efficiency is improved.