Flash / Flex Speex音频解码，播放speex文件

Question

I want to play *.spx files which encoded by Speex on the Web.
But I have no knowledge of Flash/Flex or any Flash Audio codec. After Google search for a whole day, I got some solutions, that is:

1. Do something wrapping Speex files with a FLV container because that the Speex is only playable as the audio codec in a FLV container.
   Now I can play a SPX-Audio-Only FLV file in Flex, I use netStream.play("audio-only-speex.flv") , But I donot know how to wrap a Spx file with FLV container using ActionScript.
   Any example project?

2. Decode Spx using AS.
   I checked out the fllowing pages that they all decoded OGG Vorbis but no Speex :(
   http://barelyfocused.net/blog/2008/10/03/flash-vorbis-player
   http://www.exswap.com/?p=132
   http://mauft.com/2010/11/ogg-vorbis-in-flash
   Adobe also provides a AS3 OggVorbis Library which ported by Alchemy:
   http://labs.adobe.com/wiki/index.php/Alchemy:Libraries

3. FMS: do a server streaming using FMS or Red/Xuggle. I have never heard FMS stuffs before, as well as I'm not sure whether my virtual host can support or not...

4. Convert every Spx files to MP3.

I think the best solution is decoding Spx in AS3, Yes, I'd like to make a Spx Flash Player.

So, I downloaded Speex Library from speex.org, installed Adobe Alchemy. After ./configure;make the libspeex, build libspeex/speex.c out a libspeex.swc via Alchemy. then, I donot know how to do next. How can I decode the speex audio with AS3?
My libspeex.swc: http://demo.0x123.com/libspeex.swc

, should I rewrite the libspeex using Alchemy API before build the libspeex.swc?

Although I am not professional in AS, but I have a strong ability to learn.

Answer 1

Adobe says specifically not to rely on Alchemy yet, so there's no official way to do it on the client side (as far as I know.) It's absurd given that there is clearly a speex decoder being used.

Can you use Xuggle's tricked-out version of ffmpeg (http://code.google.com/p/xuggle-ffmpeg/) to embed the speex in FLVs? If you can run xuggle in batch or on the fly, then regardless of the original audio format, you can serve a speex encoded FLV, playable from netStream.play .

ffmpeg -i test.wav -acodec libspeex -f flv -y speex.flv

For basic playing, you wouldn't even need a flash media server.

Answer 2

Now I've known that I must rewrite the speex library using alchemy API:
http://labs.adobe.com/wiki/index.php/Alchemy:Documentation:Developing_with_Alchemy:C_API
http://labs.adobe.com/wiki/index.php/Alchemy:Documentation:Developing_with_Alchemy:AS3_API

I've done a simple helloWorld. It is the first step that is troublesome. :)

#include <stdio.h>
#include "AS3.h"

static AS3_Val addNumber(void* self, AS3_Val args)
{
        double num1 = 0.0;
        double num2 = 0.0;

        AS3_ArrayValue( args, "DoubleType, DoubleType",
                       &num1, &num2);

        double sum = num1 + num2;
        return AS3_Number(sum);
}

static AS3_Val helloString(void* self, AS3_Val args)
{
        char *str = "Hello, Alchemy!";
        return AS3_String(str);
}


int main ()
{

        // define the methods exposed to ActionScript
    // typed as an ActionScript Function instance
    AS3_Val addNumberMethod = AS3_Function(NULL, addNumber);
        AS3_Val helloStringMethod = AS3_Function(NULL, helloString);

    // construct an object that holds references to the functions
    AS3_Val result = AS3_Object("addNumber: AS3ValType, helloString: AS3ValType",
                                    addNumberMethod,
                                    helloStringMethod);

    // Release
    AS3_Release(addNumberMethod);
        AS3_Release(helloStringMethod);

    // notify that we initialized -- THIS DOES NOT RETURN!
    AS3_LibInit(result);

    // should never get here!
    return 0;

}

compile using $ main.c -O3 -Wall -swc -o HelloAlchemy.swc

        import cmodule.HelloAlchemy.CLibInit;
        import mx.controls.Alert;

        private var loader:CLibInit;
        private var lib:Object;

        private function init():void
        {
            loader = new CLibInit;
            lib = loader.init();
        }
        protected function button1_clickHandler(event:MouseEvent):void
        {
            Alert.show(String(lib.addNumber(Number(3),Number(5)))); 
        }

        protected function helloStringButton_ClickHandler(event:MouseEvent):void
        {
            var str:String = String(lib.helloString());
            Alert.show(str);
        }