ClearVoice is a voice pre-processing engine consisting of software Acoustic Echo Cancellation (AEC), Noise Cancellation (NC) and Automatic Gain Control (AGC) modules that eliminate the need for an external chip.



  • Multi-platform Support: MIPS/ARM/x86
  • Multi-OS support: Android/iOS/Windows/Mac/Linux
  • WebRTC support: Integrated in WebRTC framework
  • APIs: well-defined APIs for integration with 3rd party applications/products



  • Software only solution, eliminating the need for an external chip
  • Low CPU usage, optimized for MIPS/ARM/x86 platforms



  • NC for IoT (Internet of things), mobile devices and automotive applications
  • AEC for various PC and embedded platforms – Windows, Mac, Android, iOS – and embedded full-duplex voice communication systems
  • Line Echo Cancellation (LEC) for CPE (Consumer Premises Equipment) – ATA , set top box, residential gateway


  • Acoustic Echo Cancellation (AEC)
    • Compliant with ITU-T G.167, P.340, 3GPP TS.26.131, TS.26.132, and ITU-T G.160 standards
    • Cancels echo spans of up to 128ms in a 512ms moving window
    • Greater than 90dB echo cancellation during single talk
    • Very low (6ms) algorithmic delay
    • Supports narrowband, wideband (7 KHz) and super wideband (14KHz) voice
    • Auto-tune based on platform audio interface characteristics – for commercial off-the-shelf platforms
    • Very fast (‹16 samples) double talk detection
  • Noise Cancellation (NC)
    • Noise suppression >30dB with minimal distortion
    • Convergence time is less than 300ms
    • Provides high SNR without musical noise
  • Automatic Gain Control (AGC)
    • ITU-T G.169 compliance
    • Amplifies or attenuates only speech segments
    • Programmable target power level in the range 0 to -30 dBm0