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I have 2 mp3 files that are nearly identical. The first file refused to stream down and play in my Appcelerator iPhone app that I am developing:

http://www.zerogravpro.com/temp/bad.mp3 (you'll find you can play this just fine in your browser, or download it and it plays fine)

This is 100% replicatable; it's not sporadic at all. The actual behavior is that the file begins to play in the iphone mediaPlayer for just a split second, then stops with some kind of "unknown" error. So then I took that file, opened it in audacity, removed the first split-second of silence from the beginning of the clip, and re-generated the mp3:

http://www.zerogravpro.com/temp/good.mp3

And this one works perfectly in the iphone app! 100% success each and every time. I have many mp3 files that are similar to bad.mp3 in that they play fine in any audio device, but error out when streaming/playing in iphone's media player. Audacity fixed it somehow and I need to know how/why, so that I can automate the fix in my hundreds of other mp3 files. I'd love to not have to open hundreds of files in Audacity and re-save. There must be some way to automate these fixes. How did Audacity fix the file? What did it do? I can only think of 2 possibilities:

  • The existence of a split second of silence at the beginning of the clip chokes iphone
  • Audacity fixes something non-obvious in the mp3

Experts: Any idea what the difference is between these 2 files, and how I could automatically turn "bad" mp3s into good ones, from some command-line tool or something? Thanks all.

HerrimanCoder
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1 Answers1

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I discovered that the only difference between the files that actually matter is the size. iPhone apps (at least in the simulator), when using the audio streaming library, choke on any file under 40Kb. So you have to use the standard sound library for the smaller files.

HerrimanCoder
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