Video Element Rate Controller Re-dux

Add keyboard shortcuts that will increase/decrease the playback rate for video elements.

Versión del día 5/8/2018. Echa un vistazo a la versión más reciente.

Tendrás que instalar una extensión para tu navegador como Tampermonkey, Greasemonkey o Violentmonkey si quieres utilizar este script.

You will need to install an extension such as Tampermonkey to install this script.

Necesitarás instalar una extensión como Tampermonkey o Violentmonkey para instalar este script.

Necesitarás instalar una extensión como Tampermonkey o Userscripts para instalar este script.

Necesitará instalar una extensión como Tampermonkey para instalar este script.

Necesitarás instalar una extensión para administrar scripts de usuario si quieres instalar este script.

(Ya tengo un administrador de scripts de usuario, déjame instalarlo)

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

(Ya tengo un administrador de estilos de usuario, déjame instalarlo)

// ==UserScript==
// @name         Video Element Rate Controller Re-dux
// @namespace    https://github.com/mirnhoj/video-element-playbackrate-setter
// @version      1.0
// @description  Add keyboard shortcuts that will increase/decrease the playback rate for video elements.
// @include      http*://*.youtube.com/*
// @include      http*://*.gfycat.com/*
// @include      http*://*.vimeo.com/*
// @include      https://www.facebook.com/video.php*
// @include      https://www.facebook.com/*/videos/*
// @include      https://www.kickstarter.com/*
// @require      https://cdnjs.cloudflare.com/ajax/libs/big.js/5.1.2/big.js
// @grant        none
// ==/UserScript==
/* jshint esversion: 6 */
//
// if you want to extend the functionality of this script to other sites
// besides youtube, add additional @include keys to the metadata block.
//
// if you want to change the default playback rate from 1x, change the line
// "var currentPlaybackRate = 1;" to equal something other than 1, like 1.3 to
// have all videos start playing at an increased speed, or 0.7 to have all
// videos start playing at a decreased speed.
//
// if you want change the granularity of the playback rate adjustment, change
// the line "var speedStep = 0.1;" to equal something other than 0.1, like 0.01
// for more granular adjustments, or 0.25 for less granular adjustments.


var currentPlaybackRate = 1; // default playback rate.
var speedStep = 0.125; // how much to modify speed for each keypress
var displayTimeMilliSec = 1500; // how long to show the current speed indicator in milliseconds
var enhancerExtention = true; // set to false if you aren't using Enhancer for Youtube

var infobox = document.createElement("h1");
infobox.setAttribute("id", "playbackrate-indicator");
infobox.style.position = "absolute";
infobox.style.top = "10%";
infobox.style.right = "10%";
infobox.style.color = "rgba(255, 0, 0, 1)";
infobox.style.zIndex = "99999"; // ensures that it shows above other elements.
infobox.style.visibility = "hidden";
infobox.style.marginTop = "3%";

var timeoutID;
var showDisplay = false;
var pref = "preference-changed";
var eventName = "speed";

if (document.readyState !== "loading") {
    onReady(); // Or setTimeout(onReady, 0); if you want it consistently async
} else {
    document.addEventListener("DOMContentLoaded", onReady);
}

function setPlaybackRate(rate, showInfobox) {
    rate = new Big(rate);
    // grab the video elements and set their playback rate.
    var videoElement = document.getElementsByTagName("video")[0];
    videoElement.playbackRate = rate;
    infobox.innerHTML = rate + "x";
    // add infobox to dom if it doesn't already exist.
    if (videoElement && !document.getElementById("playbackrate-indicator")) {
        videoElement.parentElement.appendChild(infobox);
    }
    // show infobox and update rate indicator.
    if (showInfobox) {
        infobox.style.visibility = "visible";
        // clear out any previous timers and have the infobox hide after the pre-set time period
        window.clearTimeout(timeoutID);
        timeoutID = window.setTimeout(function() {
            infobox.style.visibility = "hidden";
        }, displayTimeMilliSec);
        showDisplay = false;
    }
}

// mimic vlc keyboard shortcuts
function addKeyListener() {
    window.addEventListener('keydown', function(event) {
        var key = event.key;
        var videoElement = document.getElementsByTagName("video")[0];
        currentPlaybackRate = videoElement.playbackRate;
        switch (key) {
            // decrease playback rate if '[' is pressed
            case "[":
                currentPlaybackRate -= speedStep;
                showDisplay = true;
                setPlaybackRate(currentPlaybackRate, showDisplay);
                break;
            // increase playback rate if ']' is pressed
            case "]":
                currentPlaybackRate += speedStep;
                showDisplay = true;
                setPlaybackRate(currentPlaybackRate, showDisplay);
                break;
        }
        if (enhancerExtention === true) {
            window.postMessage({
                enhancerforyoutube: pref,
                name: eventName,
                value: currentPlaybackRate
            }, "*");
        }
    });
}

// show the current speed display on the video when mouse wheel is rolled on the speed element if using Enhancer For Youtube
function addWheelListener() {
    var enhancerToolbar = document.getElementById("enhancer-for-youtube-toolbar");
    var enhancerToolbarChildren = enhancerToolbar.children[0].children;
    for (var i = 0; i < enhancerToolbarChildren.length ; i++ ) {
        if (enhancerToolbarChildren[i].dataset.name === eventName) {
            var speedChild = enhancerToolbarChildren[i];
    }}
    if (speedChild) {
        speedChild.addEventListener('wheel', function(event) {
            var wDelta = event.wheelDelta < 0 ? 'down' : 'up';
            var videoElement = document.getElementsByTagName("video")[0];
            currentPlaybackRate = videoElement.playbackRate;
            switch (wDelta) {
                case "down":
                    // currentPlaybackRate -= speedStep; // uncomment to actually modify the playback speed
                    showDisplay = true;
                    setPlaybackRate(currentPlaybackRate, showDisplay);
                    break;
                case "up":
                    // currentPlaybackRate += speedStep; // uncomment to actually modify the playback speed
                    showDisplay = true;
                    setPlaybackRate(currentPlaybackRate, showDisplay);
                    break;
            }
        });
    }
}

async function onReady() {
    addKeyListener();
    if (enhancerExtention === true) {
        var i = 0;
        do {
            await wait(200);
            i++
        } while (!document.getElementById("enhancer-for-youtube-toolbar") && i < 50);
        onExtentionReady(); // Or setTimeout(onReady, 0); if you want it consistently async
    }
}

function wait(time) {
    return new Promise(resolve => {
        setTimeout(() => {
            resolve();
        }, time);
    });
}

function onExtentionReady() {
    addWheelListener();
}