Wiki

This version (18 May 2021 08:40) was approved by John Joseph.The Previously approved version (18 Mar 2021 02:21) is available.Diff

Click here to return to the ADI Algorithms page

Enhanced Stereo Capture


Description

The Enhanced Stereo Capture (ESC) algorithm takes a stereo record-signal and creates a wider stereo image. The ESC is meant as a record algorithm in order to capture an enhanced stereo image from two closely spaced microphones.

Usage

The ESC algorithm accepts two input signals obtained from two closely spaced microphones. The algorithm separates these two signals and widens the stereo image. The end perceptual result is a widened stereo image as if the audio had been captured by microphones with greater L/R separation. The algorithm is based on proprietary filtering and a Stereo Balance Gain that adjusts how much stereo effect is archived in the algorithm.

Depending on the spacing of the microphones in the record environment, a different Stereo Balance Gain should be selected. There are two recommended methods to do this required algorithm tuning (shown in the Example section).

  1. Simulated delay between the microphones to maximize the L/R separation
  2. Listening tests while adjusting the gain knob

The tuning required for method 1) can be done within SigmaStudio. The schematic image in example section shows how this is accomplished. The goal is to adjust the Stereo Balance Gain until the greatest visual difference in level is achieved between the left and right output signals..

Targets Supported

Name ADSP-214xx ADSP-215xx/SC5xx ADAU145x/146x
————————————-- ——————-- ——————————-- —————————-
Enhanced Stereo Capture NA NA S


Pins

Input

Name Type Description
———————- ————-- ———————-
LeftIn Audio First input channel
RightIn Audio Second input channel

Output

Name Type Description
—————————- ————-- ———————-
LeftOut Audio First output channel
RightOut Audio


Configurable Parameters

GUI Parameter Default Value Range Function Description
—————————————- ———————- —————— —————————————-
LRValue 0dB -20 - 20dB This gain knob control adjusts how much stereo effect is achieved in the algorithm. Depending on the spacing of the microphones in the record environment, this value should be adjusted to obtain the best stereo perceptual results


DSP Parameters

Parameter Name Description ADAU145x/146x
—————————————- —————————————————————- —————————————-
gain Linear gain value 8.24 Format
a1hpf High pass filter coefficients 8.24 Format Array
a1lpf Low pass filter coefficients 8.24 Format Array


resources/tools-software/sigmastudiov2/modules/adialgorithms/esc.txt · Last modified: 13 May 2021 06:23 by John Joseph