Entropy based variable rate compression for low-bandwidth multi-media streams

Trans-coding of Audio and video content is a recompression based on pre-processing the input and converting into a stream able wireless format over low bandwidth network which does not maintain an exactly constant bit rate. As the portable devices have an circular buffer other ad hoc networks which handles the incoming stream the encoder time indexes the stream bits according to the first frame´s request and compresses and delivers packet according to the dynamic channel bandwidth. The circular buffer is said to contain the start sequence of the frame and the remaining are delivered before the Presentation Time field without ever overrunning the buffer. The compression model uses a similar algorithm as Huffman codes and the streams are optimized to be able easily seek into each frame by using a variable unitary part and fixed offset which is multiple of 2 for easy decoding. Only the frames are transmitted and the values are shared using a lookup table between the encoder and the decoder. In this paper the encoder uses multi-channel audio to mix different PCM samples across 64 volume levels of dynamic range to achieve trans-coding fps. In this paper we define an on-demand adaptive algorithm called trans-repairing for constrained devices which takes original 2_n symbols and re-pairs it into m n symbols which are the current needs of low-power, low-bandwidth heterogeneous GPRS, ZigBee and other ad-hoc networks forming a collaborative multi-media smart wireless network.