Questions on webcam recording through Flash

[ivan_iseabloom]

Hello all,
We are currently about to release a flash application that uses Wowza.
The flash application will record people; they ask a question on a particular topic, we record the video. After a while, some videos are selected using a back office and are broadcasted on a TV Channel. on the TV show, some VIPs participate and answer the questions.

Everything is working fine but the TV channel teams are complaining about the file format that wowza delivers. They say that when they convert the flvs to a format that fits their broadcast platform, they lose the sound.

In my opinion, the guilty is flash, that uses obsolote codec, and it is impossible to tweak the format that flash delivers, and we are stuck with an old codec that is almost impossible to convert without losing the sound.
Please can someone confirm this ?
Do you have some suggestions ? is it possible to convert the flv on the server side ? I've played a bit using ffmpeg but the sound channel is not recognised.
The only solution I've found is to use a soft from EmicSoft, the only one that keeps the sound when it converts the flvs

[charlie]

If you switch to Flash CS4 to create your Flash .swf file and require Flash player 10 then you can switch over to using the Speex audio codec (rather then the default NellyMoser ASAO audio codec). You should be able to then transcode the resultant files since Speex decoders are widely available.

See this article:

http://askmeflash.com/article/1/all-...peex-for-flash

Charlie

[ivan_iseabloom]

Hello Charlie,
I have already tried both codecs ( swf is flash 10 ) but ffmpeg does not recognize the sound codec. I have reconfigured ffmpeg using ./configure --enable-libspeex but the audio track is not recognized. Maybe I've missed something ? I am still investigating.
Anyway, thank you for the reply, and for all the posts that allowed a good optimisation of the server and the application
btw, if you want to see the product in action, it will be encapsulated as a windows live messenger application but you can access it from here
http://bit.ly/d02r6d
( I am bitlying it to avoid search engine indexation )
Bye,
Ivan

[charlie]

When enabled properly speex does work properly in ffmpeg. I have it working.

Charlie

[ivan_iseabloom]

I will look further my ffmpeg configuration, to see what went wrong. Thank you again,
Ivan

[ivan_iseabloom]

It works.

ffmpeg -i source.flv -b 4096k -acodec pcm_alaw -async 1 target.mov

I specify the audio output ( pcm ) and add a "-async 1" ( without it, sound and video are out of sync )
Works well for both nellymoser and speex codec. I may be wrong, but it looks like ffmpeg can read speex and nellymoser, but cannot write them.

Best regards,
Ivan