echo ripper

convertEcho.js

function convertEchoVolume(masterL, masterR, echoL, echoR) {
    const mL = masterL > 127 ? 256 - masterL : masterL;
    const mR = masterR > 127 ? 256 - masterR : masterR;
    const eL = echoL > 127 ? 256 - echoL : echoL;
    const eR = echoR > 127 ? 256 - echoR : echoR;
    return {
        echoL: eL * 128 / mL,
        echoR: eR * 128 / mR
    };
}