STRUCTURE of DECODER VIDEO MPEG-4

Decoder of Video of MPEG-4 of personating of input of data stream, regular consecution of beet deputizing consecution draw the presented video. Data stream load the information lapped over consecution structure draw the video, what is good match for MPEG-4 of Video of International Standard 14496-2. Data stream start to explain part of video, representing part of video picture which is formed of one or more syntax structure identifying video object. Video object deputize a object contained in consecution draw the video and can be joined to become one or more coat of video object. coat of video Object represent a syntax structure identifying its own data stream and permit to get the consecution which can scale. peripheral of video Object is structure hereinafter identifying incidence single video object when shortening.A Video of Object Plane ( VOP) made of some macro block, each;every macro block builded by 8 x 8 block luminan, krominan and often also clearness of values piksel.

Stream of input Data load the information about tekstur, move, and structure each;every VOP Form the information identify the object which is taken a short cut in VOP. Information move to lessen the time-wasting whereas consecution draw the video, connecting macro block from VOP which now with the macro block develop;builded previously. Tekstur of Information didecodekan by using a algorithm lessening space extravagance.

Process the decode tekstur got first time apply all Algorithm Very Length Decoding ( VLD) explaining code word from tables Huffman. Later;Then inversi of algorithm scan rebuild the block 8 x 8 from coefficient array which quantization. After inversi of algorithm of prediksi AC & DC And inversi of quantization algorithm, a Inverse Discrete Cosine Transform ( IDCT) applied in block 8 x 8. In course of decode tekstur depicted [by] that more intensive operation computing VLD and IDCT. Decoder which is outlined in under show how big biayan operate for the VLD and IDCT for the time of decode.

Compensation algorithm move process decode of other;dissimilar costly. This algorithm rebuild each;every macro block begining from coresponding macro block to VOP rebuilt previously. If this coresponding macro block unegual ( in certain sill) with the macro block which now, a[n estimate of information of error diekstraksi from stream of data and didecode by using algorithm of decode tekstur. In this case macro block which now got as quantifying from macro block ( coresponding) with the macro block rebuilt wrong mendecode prediksi.

To identify the most expected module, have been shown implementation of software of decoder of video MPEG-4. Examination Consecution used have the long foursquare and single coat VOP ( VOP contain the foursquare object length, form without information). examination Decoder have been conducted at Pentium II 266 MHZ, to know the insuffiency of process VLIW. Have been estimated previously that computing time at Pentium II proporsional to computing time of VLIW.

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