| 摘要 |
The invention relates to an image sensor system which includes an image sensor (CCD). The image from the image sensor is read out as a video signal. In addition to image values, the video signal also contains electrical and optical black noise. Such noises should be removed from the video signal. A value corresponding to the electrical black noise can be obtained from the image sensor by reading out same additional pixel values which does not originate from image pixels. By subtracting this value from the video signal, a clamped video signal is obtained in which the electrical black noise has been reduced or removed. Additionally, by subtracting the electric block noise value, it is achieved that the clamped video signal is not clipped in the analogue-to-digital converter. The optical black noise may be removed from the signal outputted by the ADC. |
