Frame Grabber - Circuitry

Circuitry

Analog frame grabbers, which accept and process analog video signals, include these circuits:

• An input signal conditioner to buffer the analog video input signal and protect downstream circuitry.
• A circuit to recover the horizontal and vertical synchronization pulses from the input signal.
• An analog-to-digital converter.
• An NTSC/SECAM/PAL decoder, a function that can also be implemented in software.

Digital frame grabbers, which accept and process digital video streams, include these circuits:

• Physical interface to the digital video source, such as Camera Link, CoaXPress, DVI, GigE Vision, LVDS or RS-422.

Circuitry common to both analog and digital frame grabbers:

• Memory for storing the acquired image (i.e., a frame buffer).
• A bus interface through which a processor can control the acquisition and access the data.
• General purpose I/O for triggering image acquisition or controlling external equipment.