knik0 / faac

Freeware Advanced Audio Coder faac mirror
https://sourceforge.net/projects/faac/
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High quality VBR can easily exceed standard limit, break playback on iPhones #15

Open ajp9 opened 6 years ago

ajp9 commented 6 years ago

Hi. There is a flaw in how the encoder decides what is needed for an AAC stream for complex sequences when the VBR quality is above 1000 that it can exceed the bitrate above the 264/288 standard limits per channel, making some tracks unplayable on some portables like the iPhone. It's a bit counter-intuitive that soft, noisy sequences (such as at the end of a track) can raise the bit rate all the way up to 800 kbps, whereas loud sequences remain moderated and lower.

At the very least, there ought to be an option to cap the outgoing rate to the standard limits.

Thanks for all of your efforts so far.