Abstract: A quantization step determination part inputs an evaluation value (ACT_MB) indicating the dispersion in a macroblock and its average value (ACT_PIC). A subtracter obtains the difference between these values, and a multiplier multiplies the difference by raq (<1) to obtain a weighting value. Next, an adder adds the weighting value to an average quantization step value of source data, and finally a multiplier multiplies the sum by a step value adjustment factor ? (>1) to obtain a converted quantization step value (Qstep_AVC). This optimizes a bit allocation in accordance with an Activity value of the macroblock, to thereby improve the quality of image.

Abstract: A scintillator element 2 has a rod-like base material 11, and a scintillator 12 is formed by being vapor deposited radially onto a side face of the base material 11. A plurality of these scintillator elements 2 are aligned and bundled together to form a scintillator unit 1. By mounting a solid-state image pickup element 20 to an open face of a case 3 of the scintillator unit 1, an image sensor M, which serves as a radiation detector, is formed. The image sensor M can be adjusted in size by adjusting the number, etc., of the scintillator elements 2.

Abstract: A motion estimation method capable of reducing the amount of calculation as compared to a full search method. In the method, a coarse search block and fine search blocks are defined. The fine search blocks are given by dividing the coarse search block into a plurality of blocks so that the fine search blocks are contained in the coarse search block. A sparsely interpolated image and a densely interpolated image are defined. A first search is performed using the defined coarse search block and the defined sparsely interpolated image. A second search is performed using the defined coarse search block and the defined densely interpolated image. With regard to search blocks belonging to the fine search blocks, only a surrounding region of an optimal point obtained in the first search is searched.

Abstract: A scintillator element 2 has a rod-like base material 11, and a scintillator 12 is formed by being vapor deposited radially onto a side face of the base material 11. A plurality of these scintillator elements 2 are aligned and bundled together to form a scintillator unit 1. By mounting a solid-state image pickup element 20 to an open face of a case 3 of the scintillator unit 1, an image sensor M, which serves as a radiation detector, is formed. The image sensor M can be adjusted in size by adjusting the number, etc., of the scintillator elements 2.

Abstract: A quantization step determination part inputs an evaluation value (ACT_MB) indicating the dispersion in a macroblock and its average value (ACT_PIC). A subtracter obtains the difference between these values, and a multiplier multiplies the difference by raq (<1) to obtain a weighting value. Next, an adder adds the weighting value to an average quantization step value of source data, and finally a multiplier multiplies the sum by a step value adjustment factor ? (>1) to obtain a converted quantization step value (Qstep_AVC). This optimizes a bit allocation in accordance with an Activity value of the macroblock, to thereby improve the quality of image.