Converting audio to CAF format for playback on iPhone using OpenAL

Question

I am using the SoundEngine sample code from Apple in the CrashLanding sample to play back multiple audio files. Using the sample caf files included with CrashLanding everything works fine but when I try and use my own samplesconverted to CAF using afconvert all I get is a stony silence ;)

Does anyone have settings for afconvert that will produce a CAF file capable of being played back through OpenAL?

Answer 1

afconvert -f caff -d LEI16@44100 -c 1 in.wav out.caf

References:

• Apple's Multimedia Programming Guide: Using Audio: Preferred Audio Formats in iOS
• afconvert(1) man page (use afconvert -h for complete info)

Answer 2

Simple bash script to convert the mp3 files in a folder to caf for iphone

#!/bin/bash
for f in *.mp3; do
  echo "Processing $f file..."
  afconvert -f caff -d LEI16@44100 -c 1 "$f" "${f/mp3/caf}"
done

Answer 3

this is the best for size:

afconvert -f caff -d ima4 original.wav

Answer 4

thanks for the info.

also, if you're looking into additional compression with openAL, this might be of interest:

"iPhone, OpenAL, and IMA4/ADPCM" http://www.wooji-juice.com/blog/iphone-openal-ima4-adpcm.html

Answer 5

It looks like the -c is not working today, I got it with following:

afconvert -f caff -d LEI16 input.m4a output.caf