Telecommunications & Signal Processing Laboratory
Audio Demonstration
H. Najafzadeh-Azghandi and P. Kabal
"Perceptual coding of narrowband audio signals at 8 kbit/s",
Proc. IEEE Workshop on Speech Coding (Pocono Manor, Penn.),
pp. 109-110, Sept. 1997.
This paper proposes a VQ-based transform coding scheme for
audio signals (sampled at 8 kHz) at very low bit rates. This coder
uses a new perceptually based distortion measure, which takes
into account the energy of audible noise, in both training the
codebooks and selecting the best codewords. An adaptive bit allocation
strategy based on the distribution of the energy of the transform
coefficients above the masking threshold is employed to assign
more bits to perceptually important critical bands. This coder
delivers good quality for most audio signals at 1 bit/sample.
Demonstration sound files:
Orchestral music
- original uncoded
- G.729 coded
using G.729 speech coder at 8 kb/s
- IS-96 coded
using IS-96 (QCELP) speech coder at 8 kb/s
- PCONA
coded using the perceptual transform coder at 8 kb/s
Orchestral music (wide dynamic range)
- original uncoded
- G.729 coded
using G.729 speech coder at 8 kb/s
- IS-96 coded
using IS-96 (QCELP) speech coder at 8 kb/s
- PCONA
coded using the perceptual transform coder at 8 kb/s
Classical guitar
- original uncoded
- G.729 coded
using G.729 speech coder at 8 kb/s
- IS-96 coded
using IS-96 (QCELP) speech coder at 8 kb/s
- PCONA
coded using the perceptual transform coder at 8 kb/s
Female speech
- original uncoded
- G.729
coded using G.729 speech coder at 8 kb/s
- IS-96
coded using IS-96 (QCELP) speech coder at 8 kb/s
- PCONA
coded using the perceptual transform coder at 8 kb/s
Male speech
- original uncoded
- G.729 coded
using G.729 speech coder at 8 kb/s
- IS-96 coded
using IS-96 (QCELP) speech coder at 8 kb/s
- PCONA coded
using the perceptual transform coder at 8 kb/s
Paper titles.