On the refinement of the DCT/IDCT scaling factor sensitivity

This paper proposes to represent the floating-point multipliers required to perform IDCT implementations using a rational Diophantine (i.e. ratio of integers) approximation with a common denominator, which is not necessarily a power of two. A case study to support this proposal is presented by applying the proposed scheme to Chenpsilas IDCT algorithm. Results show better performance when applying the proposed scheme compared to the traditional shift process. Similar studies can be obtained for any other potential up-scaling factor, and by modifying any other potential IDCT fast algorithm.