Compression
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Compression reduces the size of data like text, images, video and audio to reduce bandwidth needed for transmission and storage requirements. It works by removing redundancy in files that humans are less likely to notice, like slight differences between frames in video. There are two main types: lossless compression preserves all the original data quality and is used for things like documents, while lossy compression can lose some data quality but provides greater size reductions, and is used for video and audio. Common video compression techniques include AVI, JPEG2000, and MPEG standards which remove spatial and temporal redundancy between frames.
Compression
- 1. COMPRESSION ANCY MARIAM BABU, VIT UNIVERSITY
- 2. Compression Compression is used to reduce the volume of data to be transmitted (text , images ,fax) To reduce the bandwidth required for transmission and to reduce storage requirements (video, audio , speech) Compression Define compression Compression can be simple and kind of compression reduce a text file to 50% of original file. How compression is possible?? - redundancy in video,audio,image file -human preception properties
- 3. Compression
- 4. Classification Lossless compression - for legal and medical documents,computer programs -exploit only data redundency lossy compression - digital video,images,audio where some eroors can be correlated. - both data redundancy and human preception properties.
- 5. Video compression Video as a sequence of pictures or frames Exploits only spatial redundancy High correlation between successive frames.only small portion of each frames is involved with any motion that is taking place The combination of actual frame content and predicted frame content are used.
- 6. Video compression techniques The examples are: Avi : audio video interleave -used to store audio and video data in file - formatted as JPEG2000: COMPRESSION STANDARD FOR STILL IMAGE -LOWER LATENCY - TYPE OF LOSSLESS COMPRESSION MPEG2 &MPEG4: VIDEO COMPRESSION STANDARD - WIDELY USED TO DVD DISCS AND DIGITAL TELEVISON BROAD CASTING - USED IN As ENCODER BEFORE TRANSMISSION