ＰＣ摄像机的前端由图像传感器和位于数字域信号处理之前的几个模拟信号调理组件（包括直流恢 复、黑电平箝位、相关二次采样、可编程增益调节和模数转换）所组成。ＰＣ摄像机的空间受到很大 限制，所以在不降低摄像机初始设备制造商（ＯＥＭ）及其用户所要求的必备性能的条件下，希望能 集成尽可能多的模拟信号处理电路。 The front end of the PC camera consists of the image sensor and several analog signal conditioning components (including DC recovery, black level clamp, correlated subsampling, programmable gain adjustment, and analog-to-digital conversion) located in front of the digital domain signal processing. The PC camera space is so limited that it is desirable to integrate as much analog signal processing circuitry as possible without reducing the required performance required by the camera OEM and its users.