Real time software implementation of scalable video codec

Scalable video compression is becoming increasingly more important in diverse, heterogeneous networks of today. In a previous work, Taubman and Zakhor (see IEEE Transactions on Image Processing, vol.3, no.5, p.572-88, 1994) developed a scalable codec capable of generating bit rates from tens of kilo bits per second to several mega bits per second with fine granularity of the available bit rates. This codec is based on 3-D subband coding and multi-rate quantization of subband coefficients, followed by arithmetic coding. We replace the arithmetic coding portion of the Taubman codec with block coding, and compare the encode/decode speed of this new coder with MPEG. Unlike MPEG, this codec requires symmetric computational power at the decoder and encoder and as such is useful in software only, real time, interactive video applications. We have found the encoding speed of the new encoder to be one order of magnitude faster than MPEG-1, without significant loss in compression efficiency.