rmfr.js

function removeAnimatedFrames() {
    let result = [];
    let i = 0;
    let freezeLastFrame = 200;
    let stillFrames = 0;
    let dropFrames = 5;
    let stillFrameThreshold = 10;
    let frame = {
        duration: recordedFrames[i].duration,
        frame: recordedFrames[i].frame,
        buffer: recordedFrames[i].buffer
    }
    result.push(frame);
    while (i + dropFrames < recordedFrames.length) {
        let dif = pixelmatch(recordedFrames[i].buffer, recordedFrames[i + 1].buffer, null, w, h, {threshold: 0.1});
        if (dif == 0) {
            if (stillFrames == stillFrameThreshold) {
                frame = {
                    duration: recordedFrames[i - stillFrameThreshold].duration,
                    frame: recordedFrames[i - stillFrameThreshold].frame,
                    buffer: recordedFrames[i - stillFrameThreshold].buffer
                };
                result.push(frame)
                stillFrames = 0;
            } else {
                result[result.length - 1].duration = result[result.length - 1].duration + recordedFrames[i + 1].duration;
                stillFrames++;
            }
        } else {
            result[result.length - 1].duration = result[result.length - 1].duration + recordedFrames[i + 1].duration;
        }
        i++;
    }
    frame = {
        duration: recordedFrames[i].duration,
        frame: recordedFrames[i].frame,
        buffer: recordedFrames[i].buffer
    };
    frame.duration = frame.duration + freezeLastFrame;
    result.push(frame);
    let secondStageResult = [];
    secondStageResult.push(result[0]);
    for (let ii = 1; ii < result.length - 1; ii++) {
        if (pixelmatch(secondStageResult[secondStageResult.length - 1].buffer, result[ii].buffer, null, w, h, {threshold: 0.1}) == 0) {
            secondStageResult[secondStageResult.length - 1].duration = secondStageResult[secondStageResult.length - 1].duration + result[ii].duration;
        } else {
            secondStageResult.push(result[ii]);
        }
    }
    return secondStageResult;
}