Group of Pictures - Everything You Need To Know

The Group of Pictures (GOP) is a fundamental concept in video compression that plays a crucial role in how digital video is processed, stored, and transmitted. It starts with an I-frame (Intra-coded frame) and is followed by a series of P-frames (Predicted frames) and B-frames (Bidirectional frames). The I-frame is a complete image and serves as a reference point for the frames that follow. P-frames contain only the changes in the image from the previous frame, while B-frames store the differences between the current frame and both the previous and following frames. This structure reduces the amount of data needed to represent a sequence of video frames. The GOP size can vary significantly based on encoder settings and content, with no fixed default size. It's often dynamically adjusted for optimal efficiency and quality, accommodating a wide range of applications and use cases.