| 摘要 |
PROBLEM TO BE SOLVED: To reduce the power consumption of an MPEG2 coder by reducing the arithmetic operation amount for motion estimation, while minimizing deterioration in image quality and to attain motion estimate with high precision by panning information. SOLUTION: A motion vector detection section 7c retrieves a motion vector of an MB to be coded in an input image buffer 7a from reference image data in a reference image buffer 7b and selects a width of a retrieval range set to a motion vector detection section 7c, depending on whether or not a variance of the motion vector obtained by a variance calculation section 7h is smaller than a threshold level and applies an offset depending on the mean value of the motion vector which is obtained by a mean value calculation section 7g for a narrow retrieval range. Furthermore, when panning information is fed to a value latch section 7e via a CPU IF 8 externally, the retrieval range of the motion vector detection section 7c is made wide or narrow, depending on the panning information and an offset depending on the panning information is applied to the retrieval range, when the retrieval range is narrow. |
