Scalable Multimode Tree Coder with perceptual pre-weighting and post-weighting for wideband speech coding

A scalable Multimode Tree Coder with perceptual pre-weighting and post-weighting filters for wideband speech is presented. The average bit-rate of the Mutlimode Tree Coder operates at 30%-60% of the bit-rate of G.722. In addition, the algorithmic delay of the Multimode Tree Coder is 12.375 ms, which is about half of AMR-WB, and computational complexity is about a third of AMR-WB. Therefore, the Multimode Tree Coder is a low delay, low complexity, and moderate bit-rate speech codec for wideband speech. The scalable wideband Multimode Tree Coder provides a variable bit rate option not available before, while maintaining good performance, low delay, and low complexity.