| 摘要 |
PURPOSE:To process picture information with a few bit at high speed and with high quality by reading picture data based on a low reference level (black) and shading correction data based on a high reference level (white) from a control memory. CONSTITUTION:A main control circuit 19 transmits command signals a, e, to open a gate G1, a referenced maximum black level DB is read by an image sensor 10 and written on a level memory 13. Then the gate G1 is closed, a referenced maximum white level DW is read by the image sensor 10, command signals a, b, e open gates G2, G3, G4, a subtractor 14 operates DW-DB, which is stored in a memory 15. Then the reading of data D is started, the gates G1, G5 remain closed by commands a-e of the main control circuit 19, other gates G2, G3, G4 and G6, G7, G8 are opened to read the shading correction data from a control memory 16 after the processing of the DW-DB at the subtractor 14 and the correction processing over the entire face of the original is finished.
|
