公开(公告)号：US07081921B2

公开(公告)日：2006-07-25

申请号：US09741218

申请日：2000-12-20

申请人： Shozo Nitta ,  Kenji Tanaka ,  Tatsuo Isumi ,  Akira Morikawa ,  Kyoji Matsusako ,  Sean Chuang ,  Mike Koen

发明人： Shozo Nitta ,  Kenji Tanaka ,  Tatsuo Isumi ,  Akira Morikawa ,  Kyoji Matsusako ,  Sean Chuang ,  Mike Koen

IPC分类号： H04N5/235

CPC分类号： H04N5/361 ,  H04N5/16 ,  H04N5/20 ,  H04N5/3655 ,  H04N5/378

摘要： A front end signal processing method and apparatus for processing a signal from an image sensor are provided for readily clamping a black level, improving the manufacturing yield, and reducing the power consumption. A luminance detector/digitizer receives a sensor output signal from an image sensor, detects luminance information included in the sensor output signal, and generates a digital luminance signal representative of the detected luminance information. A digital processor receives the digital luminance signal, and multiplies the digital luminance signal by a predetermined gain code to generate the multiplication result as a front end processed signal output. An optical black clamp receives the digital luminance signal from the luminance signal detector/digitizer and supplies a feedback signal produced from the digital luminance signal to the luminance signal detector/digitizer to clamp a black level of the luminance signal to a constant value.