Question

Flash 10 supposedly has support for the Speex audio format. I’d like to embed some Speex files in my SWF:

[Embed(source='assets/test.spx',mimeType='audio/x-speex')]
private static const SpeexSound:Class;

However, I get the error:

no transcoder registered for mimeType 'audio/x-speex'

Any ideas?

Answer 1

I’ve been researching this some more. Here are the options:

1. Embed an ogg speex file and use an Alchemy-compiled libOgg and libSpeex to decode it. The decoded bytes can be fed into Flash via SampleDataEvent.SAMPLE_DATA. Its painfully ironic that Alchemy has to be used, when we know that libSpeex lives in the Flash Player somewhere.

2. You can’t embed FLVs, but you can embed SWFs, so convert a Speex FLV into a Speex SWF. The conversion can be done with ffmpeg like this:

   $ ffmpeg -i test-with-speex.flv -vn test.swf
   

   However, that will unfortunately auto-convert the audio into MP3 inside the SWF. You should be able to preserve the codec like this

   $ ffmpeg -i test-with-speex.flv -vn -acodec libspeex test.swf
   

   but ffmpeg doesn’t currently support non-MP3 SWFs. Grr. Perhaps there’s other conversion tools that will do it?