| 摘要 |
PURPOSE:To attain easily A/D conversion of picture information, by adjusting the gain of an amplifier so as to bring a level of an analog video signal of an A/D converter output to a prescribed value in response to a sampling level of the A/D converter. CONSTITUTION:An X-ray fluoroscopic image of an X-ray TV monitor 7 is digitized with an A/D converter 9 via an amplifier 8, fetched in a CPU6 in high speed and filed in a storage device 10. The gain of the contrast level of a picture entering the converter 9 is taken sufficiently smaller in comparison with the sampling level of the converter in advance in this case, the X-ray picture is digitized and a maximum value MAX of the contrast data digitized is obtained in the CPU. The obtained MAX and a maximum sampling value MV of the converter 9 are compared at a comparator 11 and the input gain of the converter 9 is adjusted so that the MV and the MAX become a prescribed relation. Thus, the X-ray picture is digitized always in the optimum state in a short time. |
