// jshint esversion: 6, globalstrict: true, strict: true
'use strict';
var fs = require('fs');
var P2J = require('pipe2jpeg');

var spawn = require('child_process').spawn;

var jpegCounter = 0;

var params = [
    /* log info to console */
    '-loglevel',
    'quiet',
    
    /* use an artificial video input */
    '-f',
    'avfoundation',
    '-video_size',
    //'1024x768',
    '3264x2448',
    '-framerate',
    '20',
    //'15',
    '-video_device_index',
    '2',
    '-i',
    'Doccamera',

    /* set output flags */
    '-an',
    '-c:v',
    'mjpeg',
    '-pix_fmt',
    'yuvj422p',
    '-f',
    'image2pipe',//image2pipe, singlejpeg, mjpeg, or mpjpeg
    '-q',
    '2',
    '-t',
    '5',
    '-r',
    '20',
    'pipe:1'
];

var p2j = new P2J();

p2j.on('jpeg', (jpeg) => {
    console.log('received jpeg', ++jpegCounter);
    var fpath = 'c' + jpegCounter + '.jpeg';
    fs.writeFile(fpath, jpeg, function(err){
        if (err) {
            return console.log(err);
        }
        console.log('saved.');
    })
});

const ffmpeg = spawn('ffmpeg', params, {stdio : ['ignore', 'pipe', 'ignore']});

ffmpeg.on('error', (error) => {
    console.log(error);
});

ffmpeg.on('exit', (code, signal) => {
    console.log('exit', code, signal);
});

ffmpeg.stdout.pipe(p2j);

const convert_preivew = spawn('ffmpeg', params, {stdio : ['ignore', 'pipe', 'ignore']});