Abstract: An image processing apparatus includes frame memories for storing information of an image to be displayed; a block memory for dividing the information stored in the frame memories into a given number of information blocks and storing the divided information blocks; a microcomputer circuit for automatically determining a desired value of each of LEVEL and WIDTH according to given contents of the divided information blocks; and an image emphasis circuit for window-processing information of the image to be displayed according to the determined value of each of the LEVEL and WIDTH.

Abstract: An X-ray photographing device of a digital fluorographic apparatus for use in X-ray diagnosis includes an image intensifier for converting X-rays transmitted through an object to an optical image, and a TV camera for converting the optical image to a television video signal. An effective video level range of the TV camera is narrower than that of the image intensifier. In order to perform a proper X-ray transmittance correction for the object, an X-ray television video signal is converted, at levels out of the effective video level range of the TV camera, to a maximum allowable input video level. In a TV monitor, the levels of the television signal which are out of the effective video signal level range of the TV camera are displayed at the maximum signal level to permit a ready transmittance correction operation. The subtraction image is displayed in accordance with the proper corrected levels.

Abstract: In a digital fluoroscopy apparatus, digital reference data is written in a given data position of digital image data where no medical information is contained. This digital reference data has contrast level information with respect to X-ray images of an object under examination. The image data having the reference data is stored in an analogue storage device after being D/A-converted. When the image signal having the D/A-converted reference data is again A/D-converted for the digital subtraction, the contrast level of the finally-A/D-converted reference data varies from that of the original reference data. The image data having the finally-A/D-converted reference data is corrected based upon the contrast level variation from the original level in an image data correction unit.

Abstract: An X-ray apparatus is disclosed which comprises an X-ray tube, a high voltage generating circuit for applying a high voltage between the anode and the cathode of the X-ray tube, a filament heating circuit for heating a filament of the X-ray tube, first switching element connected between one terminal of said filament and the negative bus of said high voltage generating circuit, second switching element connected between the other terminal of said filament and the negative bus of said high voltage generating circuit and an inverter circuit for alternately switching said first and second switching elements at a given period to switch the tube current paths.