Is there a "simple" way to play linear PCM audio on the iPhone?
I'm making a media playback app which gets given uncompressed linear PCM (über raw) audio from a third-party decoder, but I'm going crazy when it comes to just playing back the most simple audio format I can imagine..
The final app will get the PCM data progressively as the source file stream开发者_如何学编程s from a server, so I looked at Audio Queues initially (since I can seemingly just give it bytes on the go), but that turned out to be mindfudge - especially since Apple's own Audio Queue sample code seems to go off on a magical field trip of OpenGL and needless encapsulation..
I ended up using an AVAudioPlayer during (non-streaming) prototyping; I currently create a WAVE header and add it to the beginning of the PCM data to get AVAudioPlayer to accept it (since it can't take raw PCM)
Obviously that's no use for streaming (WAVE sets the entire file length in the header, so data can't be added on-the-go)..
..essentially: is there a way to just give iPhone OS some PCM bytes and have it play them?
You should revisit the AudioQueue
code. Once you strip away all the guff you should have about 2 pages of code plus a callback in which you can supply the raw PCM. This callback is also synchronous with your main loop, so you don't even have to worry about locking.
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