| 摘要 |
PROBLEM TO BE SOLVED: To set a threshold (comparison level) for inserting one image data into the other image data to be appropriate and to correctly composite images. SOLUTION: An image composition processing circuit composites third image data based on first and second image data obtained by A/D-converting plural pieces of inputted analog image data different in display contents. An image data comparison part 34 sequentially compares image picture data with the comparison level, and generates a KEY signal when the comparison level is matched with first image data. Third image data is obtained by permitting a selector to switch the output to second image data from the first image data. A comparison level control part 20 detects the noise level range (data average maximum value to average minimum value) of the first image data within a prescribed comparison setting range and sets it to be a value (range corresponding to noise level range) corresponding to the noise level range where the comparison level is detected. |
