> Hi, I've just been having a poke about in the MSM7201 code (for my HTC > Hero). I noticed there's code in the AOSP msm kernel which uses the > audio DSP to accelerate mp3, aac, etc audio decoding. I was trying to > figure out how that was hooked into the audio subsystem. > > From what I can see it ought to be done in libaudio. The AOSP > project's libaudio is here: > http://android.git.kernel.org/?p=platform/hardware/msm7k.git;a=tree > > The code in there only uses the /dev/msm_pcm devices. However, running > strings over the libaudio.so from the binaries that came with the > phone shows it refers to /dev/msm_mp3, /dev/msm_aac. This kinda > implies that AOSP builds will be doing audio decoding entirely in > software. > > Is there a good reason the audio acceleration code is missing from the > AOSP libaudio? I mean, the hardware support code is all there in the > kernel, and it /appears/ it wouldn't exactly be hard to modify the > libaudio source to add the missing glue in. > > Am I missing something, or is this just HTC/Qualcomm trying to annoy > me again? :)
Incidentally, I see the AOSP "sound" debug utility uses the /dev/msm_mp3 device: http://android.git.kernel.org/?p=platform/system/extras.git;a=tree;f=sound;h=d95f98892bd701ffaf533d41eeac593870021274;hb=HEAD -- unsubscribe: [email protected] website: http://groups.google.com/group/android-porting
