> I'd like to understand what PCM output is produced by the Android MediaPlayer. Does it depend on the origin file being decoded (e.g. an .mp3)? > If it's not producing exactly what the PCM expects, I may get an error from the player.
Stagefright media framework decodes formats such as .mp3 to PCM, which is passed to AudioFilnger via AudioTrack for sample rate conversion, attenuation, and mixing. AudioFlinger then calls the HAL with mixed PCM. Due to AudioFlinger's involvement, the PCM seen by the HAL is not in general exactly the same as the PCM that was decoded by Stagefright. However, it's still PCM, and is typically 44.1 or 48 kHz 16-bit signed interleaved stereo for hardwired speakers/headphone out. On Thursday, November 8, 2012 5:42:21 AM UTC-8, ffxx68 wrote: > > Hi > > I'm trying to port a ICS implementation of ALSA audio to JB, or a tablet > device, under this project: > > Mainly, I have the following to integrate (which I have the patch for ICS): > > external/alsa-lib > hardware/alsa_sound > > plus some other smaller fix around, but I want to understand first of all > what to do with these two first. > > For example, I have the some files with the same names in both > hardware/alsa_sound and hardware/libhardware_legacy/ > audio (from AOSP), but their content is very different in the two > locations. > > If I keep the ones from hardware/alsa_sound, build fails. > If I copy them from hardware/libhardware_legacy/audio to > hardware/alsa_sound, I can build but I get a crash during boot. > > Which one should I keep and compile? > Once compiled, which libraries should I use from alsa_sound or > libhardware_legacy/audio? > > Basically, I don't know the approach to follow, with the ALSA integration. > I couldn't find any guide, or tutorial, so any help in that sense is > welcome too. > > Thanks in advance > Fabio > -- -- unsubscribe: [email protected] website: http://groups.google.com/group/android-porting --- You received this message because you are subscribed to the Google Groups "android-porting" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
