| 摘要 |
A method for automatically controlling an exposure time in a CMOS image sensor includes the steps of a) estimating green pixel values and counting green pixels according to respective predetermined ranges, b) calculating a first total count value and a first maximum count value of green pixels having pixel values greater than a predetermined reference range and a second total count value and a second maximum count value of the green pixels having pixel values smaller than the reference ranges, c) comparing the first total count value with the second total count value, d) comparing a third total count value of the green pixels having a pixel value within the predetermined reference range with the first maximum count value if the first total count value is greater than the second total count value, and comparing the third total count value with the second maximum count value if the second total count value is greater than the first total count value, e) capturing a next image according to a current exposure time control signal if the third total count value is greater, and calculating an exposure control rate and an exposure time control signal and capturing the next image according to the next exposure time control signal if the third total count value is smaller, and f) repeating the steps a) to e) until the final completion of capturing image. |
