Playing parts of an audio file in WebAudio - html

Instead of loading 9 different audio files with a distinct sound effect, I have compiled my sound effects into one .ogg file and I have the various start and stop times for each effect. However, I don't see any way to handle this in the WebAudio API. I'm sure there is. Anyone know?

Here's how to do it.
var context = new AudioContext();
var mainNode = context.createGainNode(0);
mainNode.connect(context.destination);
function play_sound(sound, start, length) {
var source = context.createBufferSource();
source.buffer = get_buffer(sound); // assume get_buffer gets a file that has already been
source.connect(mainNode); // loaded and decoded with context.decodeAudioData()
source.start(0, start, length);
}
// lets say I want to play a 0.2 second sound effect in sfx.ogg starting at 0.5 seconds.
play_sound('sfx.ogg', 0.5, 0.2);

Related

get the raw data of mp3 file which is downloading with the `Sound` object

I have dynamically created Sound object
var files:Object={};
files["file1"]={};
files["file1"]["snd"]=new Sound();
...... //url etc
files["file1"]["snd"].addEventListener(ProgressEvent.PROGRESS, onLoadProgress);
function onLoadProgress(event:ProgressEvent):void
//// somehow I need to get the raw data (first 48 bytes to be exact) of the mp3 file which is downloading now
}
I tried URLRequest in that fuction
var myByteArray:ByteArray = URLLoader(event.target).data as ByteArray;
but with no success
It's just funny that such a simple thing as the file data is so hard to get
flash.media.Sound is a high level class that allows you to play a sound file in one line : new Sound(new URLRequest('your url')).play(); but does not provide public access to the data being loaded
The class will handle streaming for you (more precisely, progressive download)
If you need to access id3 data, just listen the Event.ID3 event:
var sound:Sound = new Sound("http://archive.org/download/testmp3testfile/mpthreetest.mp3");
sound.addEventListener(Event.ID3, onId3);
sound.play();
function onId3(e:Event):void {
var id3:ID3Info = (e.target as Sound).id3;
trace(id3.album, id3.artist, id3.comment, id3.genre,
id3.songName, id3.track, id3.year);
}
If you really need to get the raw first 48 bytes and process them by yourself, but keep in mind you will have to deal with various mp3 formats id3/no id3, and work directly on binary data, instead of letting actionscript do the work for you.
Assuming you don't want to download the mp3 file twice, you can either:
Load the mp3 file as ByteArray with URLLoader, read the 48 bytes manually, and load the Sound instance from memory, thus losing any progressive download ability. :
var l:URLLoader = new URLLoader;
l.dataFormat = URLLoaderDataFormat.BINARY;
l.addEventListener(Event.COMPLETE, onComplete);
l.load(new URLRequest("http://archive.org/download/testmp3testfile/mpthreetest.mp3"));
function onComplete(e:Event):void {
//do whatever you need to do with the binary data (l.data)
// ...
// load sound from memory
new Sound().loadCompressedDataFromByteArray(l.data, l.data.length);
You could also load use the Sound class in the classic way (to allow progressive download), and load independently the first 48 bytes with a URLStream, and close the stream ASAP (only onie packet of network overhead, plus you might get it from cache anyway) :
var s:URLStream = new URLStream;
s.addEventListener(ProgressEvent.PROGRESS, onStreamProgress);
s.load(new URLRequest("http://archive.org/download/testmp3testfile/mpthreetest.mp3"));
function onStreamProgress(e:ProgressEvent):void {
if (s.bytesAvailable >= 48) {
// whatever you need to do with the binary data: s.readByte()...
s.close();
}
}
I'm still curious to know why you would need those 48 bytes ?
EDIT: since the 48 bytes are supposed to be fed to MP3InfoUtil, you don't need to do anything particular, just let the lib do the work :
MP3InfoUtil.addEventListener(MP3InfoEvent.COMPLETE, yourHandler);
MP3InfoUtil.getInfo(yourMp3Url);

Getting Bitmap from Video decoded with Nestream AppendBytes (AS3)?

I am wondering if someone who has handled NetStream.appendBytes in Flash knows how to get the bitmapData from a decoded video frame? I have already looked at this question but that is from 3 years ago and the more recent comment/answer seems to be gone. In 2014 has anyone managed to turn those bytes into a bitmap? I am working with Flash Player 11.8 and this is not a desktop/AIR app.
In the image below I can do steps 1) and 2) but there's a brick wall at step 3)
The problem is that simply using bitmapdata.draw(video_container); does not work but instead it throws a Policy File error even though I am using a byteArray (from local video file in the same directory as the SWF). No internet is even involved but Flash tells me that "No Policy File granted permission from the server" or such nonsense. I think the error is just a bail-out insteading of straight up saying "You are not allowed to do this.."
I have tried: trying to appease this Crossdomain.xml issue anyway and looking into all known security/domain settings. I came to the conclusion that the error is not the problem but a side effect of the issue.. The issue here being that: Flash Player is aware of the SWF's location and of any files local to it. That's okay when you pass a String as URL etc but when the Netstream data is not local to the SWF domain then it becomes a Policy File issue. Problem is my data is in the Memory not in a folder like the SWF and therefore cannot alllow bitmapData.draw since it cannot "police" an array of bytes, any known fixes for this?... (I can't even say the words I really wanted to use).
What I am trying to achieve: Is to essentially use Netstream as an H.263 or H.264 image decoder in the same way Loader is a JPEG-to-Bitmap decoder or LoadCompressed.. is an MP3-to-PCM decoder. You know, access the raw material (here RGB pixels), apply some effects functions and then send to screen or save to disk.
I know it is a little late, but I think I found a solution for your problem.
So, to avoid the Security sandbox violation #2123 Error, you have just to do like this :
// ...
net_stream.play(null);
net_stream.play('');
// ...
Hope that can help.
I know this question is a couple months old, but I wanted to post the correct answer (because I just had this problem as well and other will too).
Correct answer:
It's a bug that has been open at adobe for almost 2 years
Link to the bug on Adobe
Work Around until the bug gets fixed (I am using this and it works great):
Workaround using Sprite and graphics
To take a snapshot from a video stream we don't need NetStream.appendBytes which inject data into a NetStream object.
For that we can use BitmapData.draw which has some security constraints. That's why in many times we get a flash security error. About that, Adobe said :
"... This method is supported over RTMP in Flash Player 9.0.115.0 and later and in Adobe AIR. You can control access to streams on Flash Media Server in a server-side script. For more information, see the Client.audioSampleAccess and Client.videoSampleAccess properties in Server-Side ActionScript Language Reference for Adobe Flash Media Server. If the source object and (in the case of a Sprite or MovieClip object) all of its child objects do not come from the same domain as the caller, or are not in a content that is accessible to the caller by having called the Security.allowDomain() method, a call to the draw() throws a SecurityError exception. This restriction does not apply to AIR content in the application security sandbox. ...".
For crossdomain file creation and some other security config for AMS server, you can take a look on this post : Crossdomain Video Snapshot - Fixing BitmapData.draw() Security Sandbox Violation.
After allowing our script to get data from our video stream, we can pass to the code.
I wrote a code that play a video stream ( rtmp or http ) and take a snapshot to show it in the stage or save it as a file after applying a pixel effect :
const server:String = null; //'rtmp://localhost/vod'
const stream:String = 'stream'; // 'mp4:big_buck_bunny_480p_h264.mp4';
var nc:NetConnection;
var ns:NetStream;
var video:Video;
const jpg_quality:int = 80;
const px_size:int = 10;
nc = new NetConnection();
nc.addEventListener(AsyncErrorEvent.ASYNC_ERROR, function(e:AsyncErrorEvent):void{});
nc.addEventListener(NetStatusEvent.NET_STATUS, function(e:NetStatusEvent):void{
if(e.info.code == 'NetConnection.Connect.Success'){
ns = new NetStream(nc);
ns.addEventListener(NetStatusEvent.NET_STATUS, function(e:NetStatusEvent):void{});
ns.addEventListener(AsyncErrorEvent.ASYNC_ERROR, function(e:AsyncErrorEvent):void{});
video = new Video(320, 180);
video.x = video.y = 10;
video.attachNetStream(ns);
addChild(video);
ns.play(stream);
}
})
nc.connect(server);
btn_show.addEventListener(
MouseEvent.CLICK,
function(e:MouseEvent): void{
var bmp:Bitmap = pixelate(video, px_size);
bmp.x = 10;
bmp.y = 220;
addChild(bmp);
}
)
btn_save.addEventListener(
MouseEvent.CLICK,
function(e:MouseEvent): void{
var bmp:Bitmap = pixelate(video, px_size);
var jpg_encoder:JPGEncoder = new JPGEncoder(80);
var jpg_stream:ByteArray = jpg_encoder.encode(bmp.bitmapData);
var file:FileReference = new FileReference();
file.save(jpg_stream, 'snapshot_'+int(ns.time)+'.jpg');
}
)
function pixelate(target:DisplayObject, px_size:uint):Bitmap {
var i:uint, j:uint = 0;
var s:uint = px_size;
var d:DisplayObject = target;
var w:uint = d.width;
var h:uint = d.height;
var bmd_src:BitmapData = new BitmapData(w, h);
bmd_src.draw(d);
var bmd_final:BitmapData = new BitmapData(w, h);
var rec:Rectangle = new Rectangle();
rec.width = rec.height = s;
for (i = 0; i < w; i += s){
for (j = 0; j < h; j += s){
rec.x = i;
rec.y = j;
bmd_final.fillRect(rec, bmd_src.getPixel32(i, j));
}
}
bmd_src.dispose();
bmd_src = null;
return new Bitmap(bmd_final);
}
Of course, this is just a simple example to show the manner to get a snapshot from a video stream, you should adapt and improve it to your needs ...
I hope all that can help you.

Sequencing sounds into a ByteArray seamlessly - flash, as3

I'm creating the soundtrack for a video which consists of an intro sound clip, a looping middle one, and an end clip. I need to write these dynamically to a ByteArray and then combine them with bitmaps to make a video. It's working, except in the video output I get a tiny delay between the intro sound ending and the loop sound beginning (the audio files do not have any silence, they are seamless) - can anyone advise how I could avoid this? (_soundIntro, _soundLoop and _soundEnd are the embedded audio files.)
var baAudio:ByteArray = new ByteArray();
var baAudioIntro:ByteArray = new ByteArray();
var baAudioLoop:ByteArray = new ByteArray();
var baAudioEnd:ByteArray = new ByteArray();
var totalLength:Number = (_bitmaps.length / FLV_FRAMERATE) * 44000;
var loopLength:Number = totalLength - (_soundIntro.length * 44.1) - (_soundEnd.length * 44.1);
_soundIntro.extract(baAudioIntro, _soundIntro.length * 44.1);
_soundLoop.extract(baAudioLoop, loopLength);
_soundEnd.extract(baAudioEnd, _soundEnd.length * 44.1);
baAudio.writeBytes(baAudioIntro);
baAudio.writeBytes(baAudioLoop);
baAudio.writeBytes(baAudioEnd);
Indeed, the answer was that .mp3 encoding outside of flash tends to leave gaps at the beginning and end of audio clips, preventing a seamless loop/transition (http://www.netalive.org/swsu/archives/2007/01/gapless_mp3_loops_in_flash_1.html)
I switched to .wav files, imported to Flash (thus letting Flash handle the encoding) and it fixed the issue.

How to cache audio stream data and access it in AS3

I'm streaming an MP3 file in AS3. All is working fine (I can play it) but I'm looking to implement a 'seek' bar. This means I will need to cache the file (as it's being downloaded) and then access the cached data when the user seeks a specific time in the song.
The code to actually play the mp3 stream:
function openStream( stream )
{
var s:Sound = new Sound();
var req:URLRequest = new URLRequest(stream);
var context:SoundLoaderContext = new SoundLoaderContext(500, true);
s.load(req, context);
s.play();
}
So how would I cache the file as it's being downloaded and then access the data from the cache?
I know this is pretty far from a trivial task, so I would be grateful if you could even just provide a few links to some tutorials/docs/articles.
You do not need to cache the sound for this.
The downloaded sound data is is available as long as the sound object lives in memory.
So all you need to do is take the sound object outside the function into the class scope..
Also the play function returns the current SoundChannel used by the Sound.
private var snd:Sound = new Sound();
private var channel:SoundChannel;
function openStream( stream ) {
...
channel = snd.play();
}
To implement the seek functionality you may make use of,
bytesLoaded (To know how much of the sound is downloaded)
soundChannel.position (To know current sound position)

if I load a flv with netStream, how can I call a function when the flv stops playing

I have a website in ActionScript 3 that has lots of FLV animations that happen when you press buttons. Right now this is how I have it set up.
in AS3,
im loading FLv's (which are animations I exported in FLV form from After Effects)
with net stream. I have a timer set up for the same amount of length of time that the animations (FLV's) play and when the timer stops it calls a function that closes the stream, opens a new one and plays another video. The only problem I noticed using timers is that if the connection is slow and (animation)stops for a second, the timer keeps going, and calls the next flv too early.
Does anyone know a way to load a flv, or swf for that matter, at the end of play of the flv? so that the next FLV will always play at the end of the run time of the previous FLV, rather than using timers?
im thinking onComplete but I don't know how to implement that!?
Sequential playing is pretty easy to achieve with the OSMF framework, you should check it out. Google "osmf tutorials" and you should find a few tutorials online.
The framework is fairly recent, but it looks like it may become the de facto solution for media delivery in Flash as it's not limited to video but also audio & images.
As a developer you won't have to bother with the NetStream & NetConnection classes. Developing video solutions , as well as audio & images solutions should be streamlined and easier to handle. Only limitation is that it requires Flash 10
Here's some code for checking when a FLV ends with NetStream. I just provide snippets as I assume you got the FLV up and running already.
//create a netstream and pass in your connection
var netStream:NetStream = new NetStream(conn);
//add callback function for PlayStatus -event
var client : Object = {};
client.onPlayStatus = onPlayStatus;
netStream.client = client;
//attach your NetStream to the connection as usual
//---
//function that gets called onPlayStatus
function onPlayStatus(info : Object) : void {
trace("onPlayStatus:" +info.code + " " + info.duration);
if (info.code == "NetStream.Play.Complete") {
//play the next FLV and so on
}
}
EDIT: With your example code it will look something like this.
var nc:NetConnection = new NetConnection();
nc.connect(null);
var ns:NetStream = new NetStream(nc);
var listener:Object = new Object();
listener.onMetaData = function(md:Object):void{};
listener.onPlayStatus = function(info : Object) : void {
trace("onPlayStatus:" +info.code + " " + info.duration);
if (info.code == "NetStream.Play.Complete") {
//play the next FLV and so on
}
};
ns.client = listener;
vid1.attachNetStream(ns);
const moviename1:String = "moviename2.flv";
const moviename1:String = "moviename3.flv";
var movietoplay:String = "moviename.flv";
ns.play(movietoplay);