Accurate sound input in Actionscript? - actionscript-3

I want to create a swf or air app that takes an input and displays a graphic representation of it.
The graphic side is fine for the moment, but its always using an mp3 for example
var sound:Sound = new Sound (new URLRequest("myMP3.mp3"));
- i want it to be able to take a 'live' audio feed. How would I do that and is there a better way than using the microphone input?
thanks
dai2

Microphone input is probably the easiest way and using flash player 10.1 or AIR 2.0 you can do this. Take a look at http://www.adobe.com/devnet/air/flex/articles/using_mic_api.html
It's not as easy as using SoundMixer.computeSpectrum but offers the possibility (+ more). You'll for instance most likely want to run the data through FFT to use in visualization

Related

AS3: Recording sound as they are output/played

I understand how to record microphone input in AS3 from this doc.
Is it possible to record sound exactly as they are being output/played?
The reason is I applied some sound transform (via the global SoundMixer) to sounds that are currently playing; and I also want to record this sound data while it is being played.
I just saw this question, to clarify, I am not trying to record just all sounds on the user's computer (which is not possible). My flash app has a Youtube player in it (via their AS3 API), and it's playing some sounds. I applied transforms using SoundMixer.soundTransform, and I want to record what's being played when the user is playing it.
Thanks in advance.
Just a passing suggestion.. on my desktop it seems ABLE to record sound into Flash from a different tab playing Youtube (HTML5).. I don't know how it's doing that!!
I allow microphone here.. (none actually plugged in, and speaker out has in-ear headphones)
http://code.tutsplus.com/tutorials/create-a-useful-audio-recorder-app-in-actionscript-3--active-5836
PS: Anyone trying this must reduce Windows volume since anything above 10-20% is distorted audio into the Flash app.
And this HTML5 youtube trailer was recorded fine into the Wav file produced by Flash app above
http://www.youtube.com/watch?v=MVt32qoyhi0
So after a quick search it seems my Realtek Audio is classed as a Full-Duplex soundcard and also within its own control panel I have an option called "Multi-streaming" which is enabled/ticked. I think Full-Duplex is enough to do this though. Try options within your soundcard's own settings software. Don't know about your end-users. Some hardware will do it, some wont, there is no all-round solution outside of AIR (which makes desktop apps out of your AS3 code).

How to build iOS7 Style Audio Recorder App

I am trying to build an audio recorder app similar to iOS7 built in one and looking for guidance on what controls to use for the recording app. I understand I will be using a tableview for the list of previous recordings and a UIView for the top recording view and on tapping record adjust the table view and move down the black recording view.
How should I implement the endless horizontal scrolling view? Should I use a collection view and keep adding elements to the model array as the time increments. Also what should I use for the timer. Is there something like setInterval for Objective C like in Javascript that I can use to keep updating the UI at regular time interval?
If someone also knows of a cocoa pod or sample code that would be greatly appreciated.
For recording the simplest audiorecorder is AVAudioRecorder. Here is a simple implementation of an audio recording app: https://github.com/calmez/Recorder. AVAudioRecorder has simple metering methods where you can read volume output of the channels
Honestly though, Apple would probably use CoreAudio to get the audio because it is more optimized. Novocaine is a good core audio engine that could get you started https://github.com/alexbw/novocaine
For rendering the waveform, I would guess that Apple probably uses OpenGL. I don't see how to do it easily and efficiently otherwise. You could draw them using the standard drawing APIs for UIView like this project does (https://github.com/fulldecent/FDWaveformView) but I don't see this animating well.
For the timer, there is NSTimer

Capture video without sound in Windows Store App

I want to write a Windows Store App that can capture video (without any sound) and take pictures. Imagine a digital camera: you can preview the picture on the screen of your device before pushing the button which takes the pic.
The problem I'm facing now is the fact that the Windows.Media.Capture namespace has only classes for objects that capture video with sound (CameraCaptureUI, MediaCapture). I'm not troubled by the objects' capabilities, but by the fact that I will have to include in the manifest of the app the Microphone capability and it does not make sense for the app to use it. I need a class that uses only the Webcam capability.
Any ideas?
I found the answer and I thought I should share it. I'm sorry for answering my own question, but here goes:
One can specify in the settings of the MediaCapture object, when initializing it, that it will use only the Video part:
var mediaCaptureMgr = new MediaCapture();
var captureSettings = new MediaCaptureInitializationSettings();
captureSettings.StreamingCaptureMode = StreamingCaptureMode.Video;
await mediaCaptureMgr.InitializeAsync(captureSettings);
RTFM!

Netstream and step() or seek()?

I'm on an AS3 project, playing a video (H264). I want, for some special reasons, to go to a certain position.
a) I try it with NetStream.seek(). There it only goes to keyframes. In my current setting, this means, i can find a position every 1 second. (for a better resolution, i'd have to encode the movie with as many keyframes as possible, aka every frame a keyframe)
this is definetly not my favourite way, because I don't want to reencode all the vids.
b) I try it with NetStream.step(). This should give me the opportunity to step slowly from frame to frame. But in the documentation it says:
This method is available only when data is streaming from Flash Media Server 3.5.3 or higher and when NetStream.inBufferSeek is true.
http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/net/NetStream.html#step()
Does this mean, it is not possible with Air for Desktop? When I try it, nothing works.
Any suggestions, how to solve this problem?
Greetings & Thank you!
Nicolas
Flash video can only be advanced by seconds unless you have Flash Media Server hosting your video. Technically, that means that you can have it working as intended in Air, however, the video would have to be streaming (silly adobe...).
You have two options:
1) Import the footage as a movieclip. The Flash IDE has a wizard for this, and if you're developing exclusively in non-FlashIDE environment, you can convert and export as an external asset such as an SWF or SWC. This would then be embedded or runtime loaded into your app giving you access to the per-frame steppable methods of MovieClip. This, however, does come with some audio syncing issues (iirc). Also, scrubbing backwards is not an MC's forté.
2) Write your own video object that loads an image sequence and displays each frame in order. You'd have to setup your own audio syncing abilities, but it might be the most direct solution apart from FLVComponent or NetStream.
I've noticed that flash player 9 scrubs nice and smooth but in players 10+ I get this no scrub problem.
My fix, was to limit frequency the calls to the seek function to <= 200ms. This fixed scrubbing but is much less smooth as player 9. Perhaps because of the "Flash video can only be advanced by seconds" limitation? I used a timer to tigger the function that calls seek() for the video.
private var scrubInterval:Timer = new Timer(200);
private function videoScrubberTouch():void {
_ns.pause();
var bounds:Rectangle = new Rectangle(0,0,340,0);
scrubInterval.addEventListener(TimerEvent.TIMER, scrubTimeline);
scrubInterval.start();
videoThumb.startDrag(false, bounds);
}
private function scrubTimeline(e:TimerEvent):void {
var amt:Number = Math.floor((videoThumb.x / 340) * duration);
trace("SCRUB duration: "+duration+" videoThumb.x: "+videoThumb.x+" amt "+amt);
_ns.seek(amt);
}
Please check this Demo link (or get the SWF file to test outside of browser via desktop Flash Player).
Note: Demo requires FLV with H.264 video codec and AAC or MP3 audio codec.
The source code for that is here: Github link
In the above demo there is (bytes-based) seeking and frame by frame stepping. The functions you want to study mainly are:
Append_SEEK ( position amount ) - This will got to the specified position in bytes and search for the nearest available keyframe.
get_frame_TAG - This will extract a tag holding one frame of data. Audio can be in frames too but lets assume you have video-only. That function is your opportunity to adjust timestamps. When it's run it will also append the tag (so each "get_frame_TAG" is also a "frame step").
For example : You have a 25fps video, you want the third-frame at 4 seconds into playback...
1000 milisecs / 25 fps = 40 units for each timestamp. So 4000 ms == 4 secs + add the 40 x 3rd frame == an expected timestamp of 4120.
So getting that frame means... First find a keyframe. Then step through each frame checking the timestamps that represent a frame you want. If it isnt then change it to the same as most recent keyframe timestamp (this forces Flash to fast-forward through the frames to keep things in sync as it assumes the frame [with smaller than expected timestamp] should have been played by that time). You can "hide" the video object during this process if you don't like the look of fast-forwarding.

How to apply sound distortion in actionscript-3?

Let's say the sound input is either an embedded mp3 file or the microphone.
Is there an example of how to make it sound demonic and creepy, or like a radio transmission from the battlefield in actionscript-3 dynamically on runtime.
Reference:
http://www.youtube.com/watch?v=JAY88WH0FcU
As far as I know, you simply can't with the microphone, unless you first send it to a server.
With an audio file (embedded or not), you can distort it by playing with its bytes (ref), but its not at all a trivial task (I'm not aware of any library for "easy" sound processing).