Can I get raw PCM data from MediaPlayer or SoundPool?

Question

i use eclipse with android sdk 4.0.3 api lvl 15 to create a basic music player application.

I read and found that there are two main classes to play sounds. MediaPla

Answer 1

Hey have a look at AudioTrack for reading in bytes. You can manipulate the byte array of sound before you actually play it back. http://developer.android.com/reference/android/media/AudioTrack.html

Audiotrack is definately more easy to control, since you get access to do the raw data, but you gotta do the work yourself, instead of just loading the class (MediaPlayer) with an asset file.

Also look at this example for reading assets into a byte array http://developer.android.com/resources/samples/ApiDemos/src/com/example/android/apis/content/ReadAsset.html

I'm not sure if you can use the byte arrays for drawing a graph?

Hope this helps you ;-) The audiopart of Android really isn't that well-documented I'm afraid and hasn't been since day one ;\

Answer 2

I have strong feeling you're out of luck to get PCM from these Android classes. They're certainly too much tied to native layer (due to performance), and implementation differs on various api versions or devices. If you didn't find any PCM-related API yet, then there may not be any.

Solution would be to make audio mixer yourself, either in Java or C/C++, then you'd have PCM data. I expect it to be rather slow to get PCM data to Java, process it there, send back to audio playback. You'd probably have to go down to NDK programming.

Answer 3

I have been going through one open source project .

in that they have loaded PCM of audio file .

here is the https://github.com/google/ringdroid

hope its help you draw PCM from audio file .