What is an ISP and how does he work?

The ISP is an abbreviation for Image Signal processor, the full name is the image processor. In the whole process of camera imaging, it is responsible for receiving the raw signal data of the photosensitive element (sensor), which can be understood as the first step process of photographing and recording the whole camera, which plays an important role in image quality.

High-pass 8974 photo display process to clearly see the location of the ISP throughout the process

ISP's function is miscellaneous, it is basically related to the image effect of it is a part. It contains a plurality of image algorithm processing modules, which are more representative of the following: the black current (remove the bottom current noise), linearization (to solve the problem of data nonlinearity), shading (to solve the lens caused by the brightness attenuation and color changes), to remove the bad point (removing the bad data in the sensor), denoising (noise removal), Demosaic (raw data converted to RGB data), 3A (auto white balance, autofocus, AE), gamma (brightness mapping curve, optimized for local vs. overall contrast), rotation (angle change), sharpening (sharpness adjustment), zooming (zooming in and out), Color space conversion (convert to different color space into processing), color enhancement (optional, adjust color), skin tone enhancement (optional, optimize skin tone performance), etc.

In fact, different chip ISP, its processing process and module may be slightly different, but its principle, implementation functions are the same.

What is an ISP and how does he work?