video compression method video codec

Methods to compress video streams

A wide variety of methods are used to compress video streams. Video data contains spatial and temporal redundancy, making uncompressed video streams extremely inefficient. Broadly speaking, spatial redundancy is reduced by registering differences between parts of a single frame; this task is known as intraframe compression and is closely related to image compression. Likewise, temporal redundancy can be reduced by registering differences between frames; this task is known as interframe compression, including motion compensation and other techniques.

Video compression

Video compression is the method used to encode the movie. A video compression can be used in different video formats, which depends on the demands of the formats. Using particular video compression may has limitations of other parameters like Frame Size.

To determine which Video Compression to use, you should first know the formats and codecs that supported by the devices which you will play output videos on.

Video takes up a lot of space. Uncompressed footage from a camcorder takes up about 17MB per second of video. Because it takes up so much space, video must be compressed before it is put on the web. Compressed just means that the information is packed into a smaller space.There are two kinds of compression: lossy and lossless.

Lossy compression

Lossy compression means that the compressed file has less data in it than the original file. In some cases this translates to lower quality files, because information has been lost, hence the name. However, you can lose a relatively large amount of data before you start to notice a difference. Lossy compression makes up for the loss in quality by producing comparatively small files. For example, DVDs are compressed using the MPEG-2 format, which can make files 15 to 30 times smaller, but we still tend to perceive DVDs as having high-quality picture.

Lossless compression

Lossless compression is exactly what it sounds like, compression where none of the information is lost. This is not nearly as useful because files often end up being the same size as they were before compression. This may seem pointless, as reducing the file size is the primary goal of compression. However, if file size is not an issue, using lossless compression will result in a perfect-quality picture. For example, a video editor transferring files from one computer to another using a hard drive might choose to use lossless compression to preserve quality while he or she is working.

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Frame Size
Display Aspect
Resize Method
Video Bit Rate
Frame Rate
Audio Format
Audio Bit Rate
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