Theoretical analysis on interframe predictive coding with subpixel displacement accuracy — An exhaustive approach

A theoretical analysis on interframe predictive coding is presented in which special attention is paid on two issues that are practically important. First, the displacements between the target and reference images are usually given with limited accuracy due to quantization. Second, when the displacements are provided in subpixel accuracies, interpolation between the pixels is necessary to produce an estimation image. Our formulation takes an exhaustive approach in which we faithfully follow the process of subpixel interpolations with limited displacement accuracies. Our analysis can be used to determine how accurate the displacement vectors should be and which subpixel interpolation method should be used to optimize the rate-distortion performance.