الفهرس 
Survey on video compressionOnly 14 pages are availabe for public view
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Abstract
Video compression is essential for reducing the size of the digitized video files; therefore, they
could be conveniently exchanged over networks or stored on optical storage media. Compression
results in some changes in the original images forming the video stream and the video pattern
itself. Therefore, evaluation of compression performance is an essential component in studying
video compression.
This thesis starts with a detailed survey of video compression techniques with emphasis on the
available standards. These standards are related to JPEG, MPEG and H.261. A number of compression
techniques related to MPEG-4 standard have been selected for implementation and evaluation.
MPEG-4 employs an object-based video representation, which makes it suitable for video indexing and
retrieval. Temporal instances of video objects are referred to as video object planes (VOP), and
the shape of the video object is approximated by the coding modes 1 (Intraframe), P (Predictive),
and B (Bidirectional). An overview of the MPEG-4 architecture and implementation aspects is given.
This thesis concentrates on motion estimation aspects, which are essential for video compression.
Motion vector and the different algorithms for motion estimation are studied in details. Block
matching procedures are discussed with emphasis on the Full search and the 20-Logarithmic methods.
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Performance evaluation is then presented. Criteria chosen are mean square and mean absolute
encoding errors, compression ratio, and compression time. Different types of video clips (I00
frames) were used to test the different algorithms. The features of the three chosen clips differed
to illustrate the changes in the evaluation criteria.