Audio format for stream recording: FLV or mp4?

I'm capturing microphone (speech) input and publishing it on a flash server. I want this content to eventually be able to be streamed on iPhones as well as in the browser, so I'm wondering if I should pick the FLV or mp4 format (which encodes audio as AAC). Any thoughts, or tradeoffs I should take into account regarding file sizes and quality?

Thanks开发者_运维技巧!

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If your broadcasting application is Flash, you can only encode in NellyMoser and Speex. Adobe does offer the Flash Media Live Encoder for free which allows additional video codecs and AAC or MP3, but the license only allows its use with FMS. Both Nelly and Speex can be converted to MP3 or a plethora of other codecs with FFmpeg (should you need to). I suggest Speex if its voice and Nelly otherwise, both encode to fairly small size.

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Neither. Use MP3. I'm not sure if Flash server can host MP3s, but the Flash client can play MP3 files (presumably can play MP3 streams from URLs as well). So you may not need Flash server at all instead of just a plain old web server. I'm presuming the iPhone can play MP3s as well.

Or... use ffmpeg to transcode between the two formats as needed.