So over the past couple of weeks I have been looking into what Video Compression is, and what the standards are I keep forgetting to blog all of my research that I do for each module.
Video compression uses modern coding techniques to reduce redundancy in Video Data.
Video compression is a practical implementation of source coding in information theory. In practice most video codecs also use audio compression techniques in parallel compress the seperate, but combined data streams.
The majority of video compression algorithms use lossy compression. Large amounts of data may be eliminated while being perceptually indistinguishable. As in all lossy compression, there is a trade off between video quality, cost of processing the compression and decompression, and system requirements. Highly compressed video may present visible or distracting artefacts.
Video compression typically operates on square-shaped groups of neighbouring pixels, often called macro blocks. In areas of video with more motion, the compression must encode more data to keep up with larger number of pixels that are changing. Commonly during explosions, flames, flocks of animals, and in some panning shots, the high frequency detail leaders to quality decreases or to increase the varible bitrate.
No comments:
Post a Comment