There are several issues to be considered to develop a wireless video transmission system successfully.Problems such as the lack of bandwidth in wireless channel, and the dense nature of video data etc. The wireless video transmission system that is mentioned in this paper uses a few approaches to tackle these problems. The 3D set partitioning in hierarchical trees (SPIHT) coder is employed in our system. This coder is very efficient and proves to have real-time capability in compressing video. A grey scale image with size 72x88 needs to be represented with 50.7kbits. If we want to transmit 16 frames/s video, the system needs to have a transmission rate of 811.2kbits/s. It is well known that wireless technology has limited bandwidth. For example, bluetooth has a maximum transmission rate of 721kbits/s. The coder can achieve 40:1 compression ratio introducing minor distortion on the video. We investigated a few ways to improve the processing time of the 3D-SPIHT and its error resilience. Then we try to classify different objects in the video with different priorities. This allows us to minimise the maximum bits that are needed to encode the video sequence. The feedback from the channel is used to control the maximum bits used.
Still some development is made in the 3G technology in mobile communication.In 3G we prompt to use the B-ISDN (Broadband ISDN) which is used to transmit the data at the ultra high speed even in several Mbps towards the receiver.But the compressed data enhance the possibility of introduction of error n loss in the data received. So there some advancement is still required to improve the quality of data received.IEEE standard still working on this issue.
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