Get the raw audio in getUserMedia success callback - html5-audio

I'm trying to get the raw audio in getUserMedia() success callback and post it to the server.
The success callback receives the LocalMediaStream object.
var onSuccess = function(s) {
var m=s.getAudioTracks(s);
//m[0] contains MediaStreamTrack object for audio
//get the raw audio and do the stuff
}
But there is no attribute or method to get the raw audio from channels in MediaStreamTrack.
How can we access the raw audio into this callback which is called on success of getUserMedia()?
I found the Recorder.js library-- https://github.com/mattdiamond/Recorderjs
But it is recording blank audio in Chrome: Version 26.0.1410.64 m.
It works fine on Chrome: Version 29.0.1507.2 canary SyzyASan.
I think there is issue of Web Audio API used by recorder.js
I'm looking for the solution without Web Audio API, that should work at least on chrome's official build.

Check out the MediaStreamAudioSourceNode. You can create one of those (via the AudioContext's createMediaStreamSource method) and then connect the output to RecorderJS or a plain old ScriptProcessorNode (which is what RecorderJS is built on).
Edit: Just realized you're asking if you can access the raw audio samples without the Web Audio API. As far as I know, I don't think that's possible.

Related

Chrome extension to listen and capture streaming audio

Is it possible for a Chrome extension to listen for streaming audio from any of the browser's tabs? I would like to capture the streaming audio data and then analyse it.
Thanks
You could try 3 ways, neither one does provide 100% guarantee to meet your needs.
Before going into more detailed descriptions, I must note that Chrome extensions do not provide convenient tools for working on per connection level - sufficiently low level, required for stream capturing. This is by design. This is why the 1-st way is:
To look at other browsers, for example Firefox, which provides low-level APIs for connections. They are already known to be used by similar extensions. You may have a look at MediaStealer. If you do not have a specific requirement to build your system on Chrome, you should possibly move to Firefox.
You can develop a Chrome extension, which intercepts HTTP-requests by means of webRequest API, analyses their headers and extracts media urls (such as containing audio/mpeg MIME-type, for example, in HTTP-headers). Just for a quick example of code you make look at the following SO question - How to change response header in Chrome. Having the url you may force appropriate media download as a file. It will land in default downloads folder and may have unfriendly name. (I made such an extension, but I do not have requirements for further processing). If you need to further process such files, it can be a challenge to monitor them in the folder, and run additional analysis in a separate program.
You may have a look at NPAPI plugins in general, and their streaming APIs in particular. I can imagine that you create a plugin registered for, again, audio/mpeg MIME-type, and receives the data via NPP_NewStream, NPP_WriteReady and NPP_Write methods. The plugin can be wrapped into a Chrome extension. Though I made NPAPI plugins, I never used this API, and I'm not sure it will work as expected. Nethertheless, I'm mentioning this possibility here for completenees. This method requires some coding other than web-coding, meaning C/C++. NB. NPAPI plugins are deprecated and not supported in Chrome since September 2015.
Taking into account that you have some external (to the extension) "fingerprinting service" in mind, which sounds like an intelligent data processing, you may be interested in building all the system out of a browser. For example, you could, possibly, involve a HTTP-proxy, saving media from passing traffic.
If you're writing a Chrome extension, you can use the Chrome tabCapture API to record audio.
chrome.tabCapture.capture({audio: true}, function(stream) {
var recorder = new MediaRecorder(stream);
[...]
});
The rest is left as an exercise to the reader; MDN has more documentation on how to use MediaRecorder.
When this question was asked in 2013, neither chrome.tabCapture nor MediaRecorder existed.
Mac OSX solution using soundflower: http://rogueamoeba.com/freebies/soundflower/
After installing soundflower it should appear as a separate audio device in the sound preferences (apple > system preferences > sound). Divert the computer's audio to the 2ch option (stereo, 16ch is surround), then inside a DAW, such as 'audacity', set the audio input as soundflower. Now the sound should be channeled to your DAW ready for recording.
Note: having diverted the audio from the internal speakers to soundflower you will only be able to hear the audio if the 'soundflowerbed' app is actually open. You know it's open if there's a 8 legged blob in the top right task bar. Clicking this icon gives you the sound flower options.
My privoxy has the following log:
2013-08-28 18:25:27.953 00002f44 Request: api.audioaddict.com/v1/di/listener_sessions.jsonp?_method=POST&callback=_AudioAddict_WP_ListenerSession_create&listener_session%5Bid%5D=null&listener_session%5Bis_premium%5D=false&listener_session%5Bmember_id%5D=null&listener_session%5Bdevice_id%5D=6&listener_session%5Bchannel_id%5D=178&listener_session%5Bstream_set_key%5D=webplayer&_=1377699927926
2013-08-28 18:25:27.969 0000268c Request: api.audioaddict.com/v1/ping.jsonp?callback=_AudioAddict_WP_Ping__ping&_=1377699927928
2013-08-28 18:25:27.985 00002d48 Request: api.audioaddict.com/v1/di/track_history/channel/178.jsonp?callback=_AudioAddict_TrackHistory_Channel&_=1377699927942
2013-08-28 18:25:54.080 00003360 Request: pub7.di.fm/di_progressivepsy_aac?type=.flv
So I got the stream url and record it:
D:\Profiles\user\temp>wget pub7.di.fm/di_progressivepsy_aac?type=.flv
--18:26:32-- http://pub7.di.fm/di_progressivepsy_aac?type=.flv
=> `di_progressivepsy_aac#type=.flv'
Resolving pub7.di.fm... done.
Connecting to pub7.di.fm[67.221.255.50]:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: unspecified [video/x-flv]
[ <=> ] 1,234,151 8.96K/s
I got the file that can be reproduced in any multimedia pleer.

Using Node to stream Video to HTML5

I've been playing around with node and websockets and built a small test app that streams audio using websockets. The server breaks apart the mp3 using createReadStream, throttles the stream using node-throttle and sens the binary data using the "ws" module.
On the client side I pick up the chunks on the websocket and use decodeAudioData (http://www.html5rocks.com/en/tutorials/webaudio/intro/) to decode and play the chunk. It all works relatively ok.
What I was curious to do next was to stream video in the same manner to the HTML5 video tag. But I can't really find any reference material on the web to achieve this in the same manner as my audio test above.
Is there a video equivalent for "decodeAudioData"?
Can I feed chunks of data into a video tag?
I've got a similar sample running that I picked up from...
https://gist.github.com/paolorossi/1993068
But this isn't really what I am looking for. First of all it doesn't really seem to be streaming to me. The client buffers it all before playing it.
Also, similar to my audio test I want the stream to be throttled on the server side so that when a new client connects they join the video at whatever point it is currently at. i.e. 30 minutes in or whatever.
Thanks
OK,
I found a solution to this after much searching.
The MediaSource API is what I was looking for...
var mediaSource = new MediaSource();
var sourceBuffer = mediaSource.addSourceBuffer('video/webm; codecs="vorbis,vp8"');
sourceBuffer.append(new Uint8Array(data));
This link provided the solution...
http://html5-demos.appspot.com/static/media-source.html

org.osmf.media.MediaPlayer Throw Error: The specified capability is not currently supported

I have a back end sound.php which can return .m4a sound file from web server and I can make a web request with id to the sound.php to return specify .m4a file. i.e. sound.php?id=1234
I am now trying to use org.osmf.media.MediaPlayer and AudioElement and URLResource
var mediaPlayer:MediaPlayer = new MediaPlayer();
var ae:AudioElement = new AudioElement(new URLResource("http://xxx.com/sound.php?id=12"));
mediaPlayer.media = ae;
mediaPlayer.play();
and it throw error of The specified capability is not currently supported .I have tested the link via browser which is return a .m4a file sucessfully .
I dont understand if it is claiming the requesting method or the returned file , would somebody has any idea? Thanks
Try setting the MediaPlayer.autoPlay to true or you should wait until the media is loaded, which is signaled through the mediaPlayerStateChange event, with state READY.
[UPDATE]
As stated in the NetStream - Adobe ActionScript® 3 (AS3 ) API Reference page and also in the Supported codecs | Flash Player page:
Flash Player 9 Update 3 plays files derived from the standard MPEG-4
container format that contain H.264 video and/or HE-AAC audio, such as
F4V, MP4, M4A, MOV, MP4V, 3GP, and 3G2. One thing to note is that
protected MP4 files, such as those downloaded from iTunes or digitally
encrypted by FairPlay, are not supported.
It seems you will have to try the NetStream approach.

Using local file for Web Audio API in Javascript

I'm trying to get sound working on my iPhone game using the Web Audio API. The problem is that this app is entirely client side. I want to store my mp3s in a local folder (and without being user input driven) so I can't use XMLHttpRequest to read the data. I was looking into using FileSystem but Safari doesn't support it.
Is there any alternative?
Edit: Thanks for the below responses. Unfortunately the Audio API is horribly slow for games. I had this working and the latency just makes the user experience unacceptable. To clarify, what I need is sounething like -
var request = new XMLHttpRequest();
request.open('GET', 'file:///./../sounds/beep-1.mp3', true);
request.responseType = 'arraybuffer';
request.onload = function() {
context.decodeAudioData(request.response, function(buffer) {
dogBarkingBuffer = buffer;
}, onError);
}
request.send();
But this gives me the errors -
XMLHttpRequest cannot load file:///sounds/beep-1.mp3. Cross origin requests are only supported for HTTP.
Uncaught Error: NETWORK_ERR: XMLHttpRequest Exception 101
I understand the security risks with reading local files but surely within your own domain should be ok?
I had the same problem and I found this very simple solution.
audio_file.onchange = function(){
var files = this.files;
var file = URL.createObjectURL(files[0]);
audio_player.src = file;
audio_player.play();
};
<input id="audio_file" type="file" accept="audio/*" />
<audio id="audio_player" />
You can test here:
http://jsfiddle.net/Tv8Cm/
Ok, it's taken me two days of prototyping different solutions and I've finally figured out how I can do this without storing my resources on a server. There's a few blogs that detail this but I couldn't find the full solution in one place so I'm adding it here. This may be considered a bit hacky by seasoned programmers but it's the only way I can see this working, so if anyone has a more elegent solution I'd love to hear it.
The solution was to store my sound files as a Base64 encoded string. The sound files are relatively small (less than 30kb) so I'm hoping performance won't be too much of an issue. Note that I put 'xxx' in front of some of the hyperlinks as my n00b status means I can't post more than two links.
Step 1: create Base 64 sound font
First I need to convert my mp3 to a Base64 encoded string and store it as JSON. I found a website that does this conversion for me here - xxxhttp://www.mobilefish.com/services/base64/base64.php
You may need to remove return characters using a text editor but for anyone that needs an example I found some piano tones here - xxxhttps://raw.github.com/mudcube/MIDI.js/master/soundfont/acoustic_grand_piano-mp3.js
Note that in order to work with my example you're need to remove the header part data:audio/mpeg;base64,
Step 2: decode sound font to ArrayBuffer
You could implement this yourself but I found an API that does this perfectly (why re-invent the wheel, right?) - https://github.com/danguer/blog-examples/blob/master/js/base64-binary.js
Resource taken from - here
Step 3: Adding the rest of the code
Fairly straightforward
var cNote = acoustic_grand_piano.C2;
var byteArray = Base64Binary.decodeArrayBuffer(cNote);
var context = new webkitAudioContext();
context.decodeAudioData(byteArray, function(buffer) {
var source = context.createBufferSource(); // creates a sound source
source.buffer = buffer;
source.connect(context.destination); // connect the source to the context's destination (the speakers)
source.noteOn(0);
}, function(err) { console.log("err(decodeAudioData): "+err); });
And that's it! I have this working through my desktop version of Chrome and also running on mobile Safari (iOS 6 only of course as Web Audio is not supported in older versions). It takes a couple of seconds to load on mobile Safari (Vs less than 1 second on desktop Chrome) but this might be due to the fact that it spends time downloading the sound fonts. It might also be the fact that iOS prevents any sound playing until a user interaction event has occured. I need to do more work looking at how it performs.
Hope this saves someone else the grief I went through.
Because ios apps are sandboxed, the web view (basically safari wrapped in phonegap) allows you to store your mp3 file locally. I.e, there is no "cross domain" security issue.
This is as of ios6 as previous ios versions didn't support web audio api
Use HTML5 Audio tag for playing audio file in browser.
Ajax request works with http protocol so when you try to get audio file using file://, browser mark this request as cross domain request. Set following code in request header -
header('Access-Control-Allow-Origin: *');

Expression Encoder 4 live stream consumed by HTML 5 <video>

I'm trying to serve up a live stream (ie. completely buffered in memory, cannot access the past) and am having trouble with Expression Encoder 4.
Ideally, I'd like to just stream a bare H.264 byte stream to the client consumed by:
<video id="mainVideoWindow">
<source src='http://localhost/path/to/my/stream.mp4' type='video/mp4' />
</video>
I figured I could stream it to the client just like any other byte stream over HTTP. However, I'm having trouble figuring out the appropriate code required to do (first day with Expression Encoder, not sure how to go about getting the raw byte stream) so nor do I know if it would work in the first place.
An alternate was to use IIS Live Streaming server:
var source = job.AddDeviceSource(device, null);
job.ActivateSource(source);
job.ApplyPreset(LivePresets.VC1IISSmoothStreaming720pWidescreen);
var format = new PushBroadcastPublishFormat();
format.PublishingPoint = new Uri("http://localhost/test.isml");
job.PublishFormats.Add(format);
job.StartEncoding();
// Let's listen for a keypress or error message to know when to stop encoding
while (Console.ReadKey(true).Key != ConsoleKey.X) ;
// Stop our encoding
Console.WriteLine("Encoding stopped.");
job.StopEncoding();
However, I'm having trouble getting the client side markup to want to display the video on Chrome and I haven't seen anything to indicate that it'd work on Chrome (though http://learn.iis.net/page.aspx/854/apple-http-live-streaming-with-iis-media-services indicates how it would work with an iOS device).
Anyone have any insights?
You are trying to consume (with your sencond example) a Smooth Streaming feed (HTTP-Adaptive Streaming by Microsoft) through HTML5, which is not supported.
This could work on iOS devices if you enable the Apple HTTP Live Streaming to transmux the fragments into MPEG-2 Transport Stream. This will also generate an Apple HTTP Live Streaming manifest which than can be called though the video tag.
...I saw that you have the IIS link. The Apple HTTP Live Streaming needs to be enabled on the IIS Server (IIS Media Services). This will work for iOS devices. Quicktime will get into play...