摘要 |
The black level in raw image data captured from an image sensor does not always stay fixed at a constant level, but may change as a function of the analog gain and exposure time and may vary from one spatial location of the pixels to another. To carry out black-level correction on the raw image data, the black level of each of the color components is measured at one or more sampling locations. A look-up table is generated based on the measured black levels and a computation module is used to carry out black-level correction based on the information stored in the look-up table. The look up table may have information indicative of the analog gain level and the exposure time and the variations of black-levels in different spatial locations. |