Muvoc Voice Coder

MUVOC Variable Bit Rate Coder

MUVOC Variable Bit Rate Coder combines MUVOC synthesis and analysis parameters with a variable bit rate coder function. It allows the compression of the voice while sustaining a very low medium bit rate.

This module preserves a high perceptual quality for a variable and optimum bit rate (while fixed-rate coders offer a fixed binary rate for a variable quality). The average bit rate depends on the signal complexity and the sample frequency (from 8 kHz to 96 kHz).

MUVOC Fixed Bit Rate Coder

MUVOC Fixed Rate Coder combines MUVOC synthesis and analysis parameters with a fixed bit rate coder function and can only compresses voice. The fixed rate can be set in the range of 3 to 5 kbps at 8000 Hz.

 

Sound Examples

Sample Rate (Hz)
 Original
12 000
24 000
48 000
 
Sample Rate (Hz)
 Bit Rate (bps)
 Variable Coder
12 000
 15 685
24 000
 28 987
48 000
 35 838
Sample Rate (Hz)
 Bit Rate (bps)
Fixed Coder
12 000
 8 000
24 000
 12 800
48 000
 22 400

3 available options for both coders

MUVOC Noise Reduction

  • Reduces quantification and ambient noise to emphasize the voice.
  • A MUTE function prevents the coding of the noise; only the voice is coded.
  • Reduces drastically the bit rate.
  • Increases vocoder efficiency and clears the voice.
  • The MUTE function can turn MUVOC Fixed Coder into a variable coder (voice only = maximum rate, noise only = minimum rate)

 MUVOC Frame Recover

  • Recovers voice frames lost in the digital voice transmission (RF, VoIP,...).
  • Maintains a quality transmission up to 20%-30% of frame loss.

 MUVOC Variable Speed Synthesis

  • Synchronizes receiver and transmitter sampling frequencies in digital communication.
  • Listening speed may be adjusted to play messages at a more convenient speed.
  • Enables fast forward or rewind functions in digital recorders.

 

Application Examples

  • Answering machines
  • Radio communications
  • Voice over IP
  • Network games
  • Toys
  • Video post production
  • Alarms
  • Advertisements...