Major components of a video conferencing system include the capture, encode, decode and display systems. Each of these systems must work with un-compressed image data, and in general they all use different pixel formats. This makes pixel format conversion an essential part of any video conferencing application.
The capture system uses video camera hardware to generate a stream of un-compressed images. The pixel format used depends on the camera hardware, so any format could be used here. The encoders and decoders translate between un-compressed images and compressed bit-streams. Encoders and decoders generally use a YUV pixel format for un-compressed images. Video displays are usually arrays of red, green and blue pixels in hardware, so RGB pixel formats are usually required.