nicolae-olariu · October 2, 2021 21:05
diff --git a/ffmpeg-hls.html b/ffmpeg-hls.html
 <!DOCTYPE html>
 <html lang='`en'>
 <head>
    <meta charset='utf-8'/>
    <title>Audio only stream example</title>
    <script src="//cdn.jsdelivr.net/npm/hls.js@latest"></script>
    <style>
        video {
            width: 640px;
            height: 360px;
        }
    </style>
 </head>
 <body>
    <h1>HLS/<code>ffmpeg</code></h1>
    <div>
        Put this file together with <code>video.mkv</code> in a directory, and
        serve that directory with any web server.
    </div>
    <div>
        <ul>
            <li>
                <a href='https://www.ffmpeg.org/documentation.html'>ffmpeg docs</a>
            </li>
            <li>
                <a href='https://trac.ffmpeg.org/wiki/Encode/H.264'>h264 presets. profiles, etc</a>
            </li>
            <li>
                <a href='https://blog.twitch.tv/live-video-transmuxing-transcoding-ffmpeg-vs-twitchtranscoder-part-i-489c1c125f28'>
                    Twitch Post on why they do not use ffmpeg
                </a>
            </li>
            <li>
                The <code>-hls_time</code> option still waits for the next
                keyframe in the video. To make the hls segments less than 10
                seconds, I need to figure out how to adjust the keyframes.
            </li>
            <li>
                I tried using in the <code>-x264-params "keyint=x:min-keyint=y"
                </code> option to set change the keyframe frequency (described in
                <a href='https://superuser.com/questions/908280/what-is-the-correct-way-to-fix-keyframes-in-ffmpeg-for-dash'>this superuser post</a>),
                but didn't have any luck. Another 
                <a href='https://stackoverflow.com/questions/28906259/ffmpeg-hls-live-streaming-how-to-generate-shorter-segments'>stackoverflow</a>
                post said you need to use the <code>-g</code> option. 
            </li>
            <li>
                It looks like we can use the <code>-g</code> and
                <code>-flags +cgop</code> options to enable smaller chunk
                segment sizes. This was also giving me some artifacts. These are
                documented in the ffmpeg <a href='https://www.ffmpeg.org/ffmpeg-codecs.html#Codec-Options'>codec docs</a>
            </li>
            <li>
                <code>-hls_list_size</code> is the number of segments that
                will be listed in the playist file.
            </li>
            <li>
                <code>-hls_wrap</code> is the point where the segment filenames
                will wrap. Obviously, wrap needs to be greater than
                <code>-hls_list_size</code>. 
            </li>
            <li>
                It looks like the <code>-flags global_header</code> option is
                undesirable. When I enabled it, the video would only play iff
                the first segment was in the playlist file.
            </li>
            <li>
                A few times, I've messed up, because the browser caches the
                playlist file, and this causes all sorts of issues. You can
                disable the cache in the browser, OR configure the http server
                to not cache files. The <code>-c-1</code>  flag does this in 
                npm <code>node-server</code>.
            </li>
        </ul>
    </div>
    <h2>Live Stream Audio and Video via DASH</h2>
    <pre>
 ffmpeg -v verbose \
    -re \
    -i video.mkv \
    -c:v libx264 \
    -b:v 5000k \
    -f hls \
    -hls_time 6 \
    -hls_list_size 4 \
    -hls_wrap 40 \
    -hls_delete_threshold 1 \
    -hls_flags delete_segments \
    -hls_start_number_source datetime \
    -preset superfast \
    -start_number 10 \
    ./stream.m3u8
    </pre>
    <div>
        <!-- <button onclick='start("audio")'>audio</button> -->
        <button onclick='start()'>video</button>
        <button onclick='stop()'>stop</button>
    </div>
    <video controls src="/stream.m3u8"></video>

 <script>
    var url = '/stream.m3u8';
    var element;
    var player;

    var log = function(text) {
        console.log(text);
        var e = document.createElement('div');
        e.innerHTML = text;
        document.body.appendChild(e);
    }

    var start = window.start = function ()  {
        stop();
        // Create a video element
        element = window.element = document.createElement('video');
        document.body.appendChild(element);

        if (Hls.isSupported()) {
            player = new Hls();
            player.attachMedia(element);
            player.on(Hls.Events.MEDIA_ATTACHED, function() {
                log('bound hls to DOM element');
                player.loadSource(url);
                player.on(Hls.Events.MANIFEST_PARSED, function(event, data) {
                    log('manifest loaded with ' + data.levels.length + ' quality level(s)');
                    element.play();
                });
            });
            player.on(Hls.Events.ERROR, function (event, data) {
                var errorType = data.type;
                var errorDetails = data.details;
                var errorFatal = data.fatal;

                switch(data.details) {
                case Hls.ErrorDetails.FRAG_LOAD_ERROR:
                    log('error: FRAG_LOAD_ERROR'); debugger;
                    break;
                case Hls.ErrorDetails.MEDIA_ERROR:
                    log('error: MEDIA_ERROR'); debugger;
                    break;
                case Hls.ErrorDetails.OTHER_ERROR:
                    log('error" OTHER_ERROR'); debugger;
                    break;
                default:
                    log('default error:??')
                    break;
                }
            });
        } 
        else if (element.canPlayType('application/vnd.apple.mpegurl') !== '') {
            element.src = url;
            element.addEventListener('loadedmetadata', function() {
                element.play();
            });
        } else {
            throw new Error('hls not supported');
        }
    };

    var stop = window.stop = function() {
        if (element) {
            element.pause();
            element.parentNode.removeChild(element);
            element = null;
            player = null;
        }
    };

    document.addEventListener("DOMContentLoaded", function() {log('hello!');});
 </script>
 </body>
 </html>
	<!DOCTYPE html>
	<html lang='`en'>
	<head>
	<meta charset='utf-8'/>
	<title>Audio only stream example</title>
	<script src="//cdn.jsdelivr.net/npm/hls.js@latest"></script>
	<style>
	video {
	width: 640px;
	height: 360px;
	}
	</style>
	</head>
	<body>
	<h1>HLS/<code>ffmpeg</code></h1>
	<div>
	Put this file together with <code>video.mkv</code> in a directory, and
	serve that directory with any web server.
	</div>
	<div>
	<ul>
	<li>
	<a href='https://www.ffmpeg.org/documentation.html'>ffmpeg docs</a>
	</li>
	<li>
	<a href='https://trac.ffmpeg.org/wiki/Encode/H.264'>h264 presets. profiles, etc</a>
	</li>
	<li>
	<a href='https://blog.twitch.tv/live-video-transmuxing-transcoding-ffmpeg-vs-twitchtranscoder-part-i-489c1c125f28'>
	Twitch Post on why they do not use ffmpeg
	</a>
	</li>
	<li>
	The <code>-hls_time</code> option still waits for the next
	keyframe in the video. To make the hls segments less than 10
	seconds, I need to figure out how to adjust the keyframes.
	</li>
	<li>
	I tried using in the <code>-x264-params "keyint=x:min-keyint=y"
	</code> option to set change the keyframe frequency (described in
	<a href='https://superuser.com/questions/908280/what-is-the-correct-way-to-fix-keyframes-in-ffmpeg-for-dash'>this superuser post</a>),
	but didn't have any luck. Another
	<a href='https://stackoverflow.com/questions/28906259/ffmpeg-hls-live-streaming-how-to-generate-shorter-segments'>stackoverflow</a>
	post said you need to use the <code>-g</code> option.
	</li>
	<li>
	It looks like we can use the <code>-g</code> and
	<code>-flags +cgop</code> options to enable smaller chunk
	segment sizes. This was also giving me some artifacts. These are
	documented in the ffmpeg <a href='https://www.ffmpeg.org/ffmpeg-codecs.html#Codec-Options'>codec docs</a>
	</li>
	<li>
	<code>-hls_list_size</code> is the number of segments that
	will be listed in the playist file.
	</li>
	<li>
	<code>-hls_wrap</code> is the point where the segment filenames
	will wrap. Obviously, wrap needs to be greater than
	<code>-hls_list_size</code>.
	</li>
	<li>
	It looks like the <code>-flags global_header</code> option is
	undesirable. When I enabled it, the video would only play iff
	the first segment was in the playlist file.
	</li>
	<li>
	A few times, I've messed up, because the browser caches the
	playlist file, and this causes all sorts of issues. You can
	disable the cache in the browser, OR configure the http server
	to not cache files. The <code>-c-1</code> flag does this in
	npm <code>node-server</code>.
	</li>
	</ul>
	</div>
	<h2>Live Stream Audio and Video via DASH</h2>
	<pre>
	ffmpeg -v verbose \
	-re \
	-i video.mkv \
	-c:v libx264 \
	-b:v 5000k \
	-f hls \
	-hls_time 6 \
	-hls_list_size 4 \
	-hls_wrap 40 \
	-hls_delete_threshold 1 \
	-hls_flags delete_segments \
	-hls_start_number_source datetime \
	-preset superfast \
	-start_number 10 \
	./stream.m3u8
	</pre>
	<div>
	<!-- <button onclick='start("audio")'>audio</button> -->
	<button onclick='start()'>video</button>
	<button onclick='stop()'>stop</button>
	</div>
	<video controls src="/stream.m3u8"></video>

	<script>
	var url = '/stream.m3u8';
	var element;
	var player;

	var log = function(text) {
	console.log(text);
	var e = document.createElement('div');
	e.innerHTML = text;
	document.body.appendChild(e);
	}

	var start = window.start = function () {
	stop();
	// Create a video element
	element = window.element = document.createElement('video');
	document.body.appendChild(element);

	if (Hls.isSupported()) {
	player = new Hls();
	player.attachMedia(element);
	player.on(Hls.Events.MEDIA_ATTACHED, function() {
	log('bound hls to DOM element');
	player.loadSource(url);
	player.on(Hls.Events.MANIFEST_PARSED, function(event, data) {
	log('manifest loaded with ' + data.levels.length + ' quality level(s)');
	element.play();
	});
	});
	player.on(Hls.Events.ERROR, function (event, data) {
	var errorType = data.type;
	var errorDetails = data.details;
	var errorFatal = data.fatal;

	switch(data.details) {
	case Hls.ErrorDetails.FRAG_LOAD_ERROR:
	log('error: FRAG_LOAD_ERROR'); debugger;
	break;
	case Hls.ErrorDetails.MEDIA_ERROR:
	log('error: MEDIA_ERROR'); debugger;
	break;
	case Hls.ErrorDetails.OTHER_ERROR:
	log('error" OTHER_ERROR'); debugger;
	break;
	default:
	log('default error:??')
	break;
	}
	});
	}
	else if (element.canPlayType('application/vnd.apple.mpegurl') !== '') {
	element.src = url;
	element.addEventListener('loadedmetadata', function() {
	element.play();
	});
	} else {
	throw new Error('hls not supported');
	}
	};

	var stop = window.stop = function() {
	if (element) {
	element.pause();
	element.parentNode.removeChild(element);
	element = null;
	player = null;
	}
	};

	document.addEventListener("DOMContentLoaded", function() {log('hello!');});
	</script>
	</body>
	</html>