Control youtube video with DJ device.
// ==UserScript==
// @name Youtube DJ
// @namespace http://qaq.link/
// @version 0.2
// @description Control youtube video with DJ device.
// @author DKing
// @match http://www.youtube.com/*
// @match https://www.youtube.com/*
// @grant none
// @require https://gitcdn.xyz/cdn/djipco/webmidi/b86fac967652b5753575eb42ea70b602553caf59/webmidi.min.js
// ==/UserScript==
(function() {
'use strict';
var mapping = {
"DJ-202": {
"shift": [159, 0], // raw midi message ([159, 0, 127] for ON and [159, 0, 127] for OFF)
"video": {
"channel": 2,
"wheel": 6, // note
"forward": 65, // value
"backward": 63, // value
"play": 0 // note
},
"audio": {
"channel": 1,
"wheel": 6, // note
"forward": 65, // value
"backward": 63, // value
"mute": 0 // note
}
}
};
var video_player = null;
var auto_pause = false;
var shift_factor = 1;
var video_direction = 0;
var audio_direction = 0;
function check_videoplayer(){
if(video_player == null){
console.log("video not found");
video_player = document.getElementsByTagName('video')[0];
return false;
}
return true;
}
function change_video(v){
if(!check_videoplayer())return;
if(!video_direction)return;
video_player.currentTime += (v+1)*video_direction*shift_factor/30;
}
function change_audio(v){
if(!check_videoplayer())return;
if(!audio_direction)return;
var newvol = video_player.volume + 0.05*(v+1)*audio_direction*shift_factor;
if(newvol>1)newvol=1;
if(newvol<=0)newvol=0;
video_player.volume = newvol;
}
WebMidi.enable(function (err) {
if(WebMidi.inputs.length >= 1){
for(var devicename in mapping){
var rule = mapping[devicename];
var inputdev = WebMidi.getInputByName(devicename);
var outputdev = WebMidi.getOutputByName(devicename);
inputdev.addListener('noteon', rule["video"]["channel"],
function (e) {
//console.log(e);
if(!check_videoplayer())return;
if(e.note.number == rule["video"]["wheel"]){
var playing = !video_player.paused;
if(playing){
video_player.pause();
auto_pause = true;
}
}
if(e.note.number == rule["video"]["play"]){
if(video_player.paused)
video_player.play();
else
video_player.pause();
}
}
);
inputdev.addListener('noteoff', rule["video"]["channel"],
function (e) {
//console.log(e);
if(!check_videoplayer())return;
if(e.note.number == rule["video"]["wheel"]){
if(auto_pause){
video_player.play();
auto_pause = false;
}
}
}
);
inputdev.addListener('midimessage', 'all', function (e) {
// UNCOMMENT THIS TO CONFIGURE YOUR DEVICE
//console.log(e);
if(e.data[0] == rule["shift"][0] && e.data[1] == rule["shift"][1])
if(e.data[2] == 0)shift_factor = 8;
else shift_factor = 1;
});
inputdev.addListener('controlchange', 'all', function(e){console.log(e);});
inputdev.addListener('controlchange', [rule["video"]["channel"], rule["audio"]["channel"]],
function (e) {
//console.log(e);
if(e.channel == rule["video"]["channel"] && e.data[1] == rule["video"]["wheel"]){
if(e.data[2] == rule["video"]["forward"]){
video_direction = 1;
}
if(e.data[2] == rule["video"]["backward"]){
video_direction = -1;
}
}
if(e.channel == rule["audio"]["channel"] && e.data[1] == rule["audio"]["wheel"]){
if(e.data[2] == rule["audio"]["forward"]){
audio_direction = 1;
}
if(e.data[2] == rule["audio"]["backward"]){
audio_direction = -1;
}
}
}
);
inputdev.addListener('pitchbend', [rule["video"]["channel"], rule["audio"]["channel"]],
function (e) {
//console.log(e);
if(e.channel == rule["video"]["channel"]){
change_video(e.value);
}
if(e.channel == rule["audio"]["channel"]){
change_audio(e.value);
}
}
);
}
}
});
})();