Software for Telecoms & Audio
Hi-Fi Band Audio Coder DSP C Code
this proprietary audio coder operates a sample rate of 32kHz on an audio
bandwidth of 50Hz - 15kHz. The compression is to 96, 112, or 128kb/s,
selectable at the main routine interface. The input-output samples are
16-bit as is the coder dynamic range. The algorithm uses Adaptive Differential
Pulse Code Modulation (ADPCM) in a sub-band configuration. As such it
is a waveform coder and so transcodes many different types of audio signals.
Single voice, multiple voices, and music all sound clear and natural through
headphones or loudspeakers, though not quite with "CD" quality
because of the coder limitations. Hence the coder is termed "Hi-Fi
Band" as opposed to proper hi-fi for CD quality which has a wider
audio bandwidth (44.1kHz sample rate) and better dynamic range (24 bits).
- #example figures from compiling for the TI TMS320C5000(C55x) DSP processor
Availability: NOW - sale is under licence - integration support offered