The major advantage of mpeg compared to other video

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The major advantage of MPEG compared to other video and audio formats is that MPEG files are much smaller for the same quality . This is because MPEG uses very sophisticated compression techniques. MP3 is part of the MPEG standard.
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P.38 MPEG-2 for Cable TV and DVD MPEG-2 is the first popular MPEG standard. It is typically used to encode audio and video for broadcast signals, including direct broadcast satellite and Cable TV . With some modifications, it is also the coding format used by standard commercial DVD movies and HDTV (High Definition Television) . Key techniques used include inter-frame prediction and coding in the frequency domain (Discrete Cosine Transform coding/DCT). In predictive coding, the coder and decoder use an algorithm to predict what many intermediate frames should be based on some anchor frames. The coder encodes only the difference between the actual frame and the predicted. If this difference is small most of the time, there is not as information to encode. DCT takes advantage of the fact that most signal energy is at low frequencies and that there are often many consecutive zero values in the amplitudes of adjacent frequency components
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P.39 MPEG-4 MPEG-4 is a more advanced standard for video and audio compression introduced in late 1998. (HKUST played a key role here!) The MPEG-4 standard is now used in web (streaming media) and CD distribution , conversation (videophone), video-conference and broadcast television. MPEG-4 absorbs many of the features of MPEG-2, and adds advanced techniques such as motion estimation – predicting how blocks of pixels will move across the picture in successive frames. Most features included in MPEG-4 are optional and left to individual developers to decide whether to implement them.
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