A Wireless Video Coding Scheme Based On The Bit-plane Coding Of FGS

With the rapid development of information technology and social progress,multimedia, in particular, video has become more and more an indispensable partof the everyday work and life of human beings. Combined with internet, it hasbeen the goal of modern mobile communication(3G beyond or 4G)to providevarious service quality and personalized content of business for the user at the endof mobile equipment. The progress of wireless video transmission technology hasprofoundly impacted the frame and protocol of wireless network. It has been afocus of study to transmit video effectively in wireless environment.For time-based multimedia data like video, the receivers on network have twomain demands. First, to start immediately, that is without long delay. Second, toplay continuously, namely, without being interrupted during playing. So theservers must make the video data to be transmitted into packs with time stamp.Then transmit them to the user through network. And they must make the packs tobe received in time. However these demands can not be guaranteed on the currentnetwork. There are two aspects in solving the problem. First, from the networkpoint of view, the key is how break the current network frame and set up a newnetwork system with quality of service (QoS). However, internet and wirelesscommunication being more and more popular, it is difficult to alternate the currentnetwork frame, and can not be completed within short time. On the other hand,from the signal processing point of view, the key is to study applying the currentvideo coding technology to network transmission and to study new video codingalgorithm satisfying network transmission. Some traditional technologies havebeen applied to network. Such as error resilience, error concealment, channelcoding, adaptive coding, transcoding and bit-stream switching. And some progresshas been made. Among the video coding algorithm suitable for networktransmission, the idea scalable coding is put forward, including temporal scalablecoding, fine granular scalable (FGS) coding and progressive fine granular scalable(PFGS) coding, etc. the data stream of the methods mentioned above havecharacter of scalability and error resilience. They can adapt to the change of bandwidth and error. However, the coding property may certainly be degraded. Bit-plane coding is the key technology of FGS coding. With the applying ofthis technology, the enhancement bit stream can be truncated at any position. Sothe bit stream is scalable and suitable for transmitting video through internet orwireless channel. In this paper we discuss the bit-plane coding and it's applicationin video transmission in detail. First of all, we introduce some basic knowledge of video coding, such asentropy coding, source coding, and mixture coding. Then we introduce thecharacters of internet and wireless channel and the problems of wireless videotransmission. Including Heterogeneity, Band width, Delay, Loss and Error etc.And we also introduce the application of traditional video coding methods to videotransmission on web, such as Minimum Transmission, Adaptive Coding,Transcoding, Bit-stream Switching and Hierarchical Scalable coding. Next weintroduce the bit-plane coding method of the FGS and it's main application tovideo coding. The bit stream of the enhancement layer can be truncated at anyposition with the application the bit-plane coding to enhancement layer. Thequality of the video reconstructed by the decoder is in proportion to the amount ofthe bits being received and therefore it has the character of fine fluctuation ofquality. In the scheme of fine granular spatial scalability, the input video is downsampled at the beginning, then it is compressed to the given bit rate applying anynon-scalable coding methods. For enhancement layer, the bit-plane codingtechnology is applied. The coefficients to be coded in the enhancement layer arecoded according to the bit plane order from high bit to low. Then the bit stream ofthe enhancement layer can be truncated at any position and have the character ofscalability. The fine scalable sub-band coding method applies sub-band coding instation picture to the enhancement layer coding of FGS. It re-arranges the DCTcoefficients to form sub-band of different frequency. Then define context and codethe sub-band coefficients with the coding method of context algorithm codingbased on bit plane. This coding method based on sub-band can not only improvethe efficiency of enhancement coding, but also remain the scalability of FGS. Thewater ring scanning method of enhancement layer codes the important area of theframe of the video first, then codes the rest of the frame. The method can improvethe subject quality of the decoded picture effectively and remain all the merits of...