| 摘要 |
PURPOSE:To attain high compression rate by applying coding (ADRC) suitable for a dynamic range for each sub block and applying prediction coding to a code signal generated in the ADRC in a block and an additional data. CONSTITUTION:A detection means 4 detects a dynamic range for each small block, a subtraction means 8 applies, e.g. subtraction of a mean value and a normalized picture element data is coded corresponding to the dynamic range. Then prediction coding means 16, 17 apply prediction coding respectively to a code signal generated by the coding and an additional data (dynamic range and mean value). In the case of prediction coding, a code signal and an additional data in a same block are in use and since the correlation is comparatively large in the code signal and the additional data in a block, the redundancy is eliminated by prediction coding. Thus, high compression rate is attained. |
