Playing PCM WAVE sound from memory with OpenSL on Android

Question

I'm trying to set up OpenSL AudioPlayer to use memory I've allocated to playback a wav file. I want to do this so I can have multiple AudioPlayers that share the same data and conserve memory.

I've tried to give openSL the entire file and tell it that it is a WAVE with format_mime

 SLDataLocator_Address loc_fd = {SL_DATALOCATOR_ADDRESS, data, size};
SLDataFormat_MIME format_mime = { SL_DATAFORMAT_MIME, (SLchar*)"audio/x-wav",SL_CONTAINERTYPE_WAV};
SLDataSource audioSrc = { &loc_fd, &format_mime };
// configure audio sink
SLDataLocator_OutputMix loc_outmix = { SL_DATALOCATOR_OUTPUTMIX,outputMixObject };
SLDataSink audioSnk = { &loc_outmix, 0 };
// create audio player
const SLInterfaceID ids[2] = { SL_IID_SEEK, SL_IID_PLAYBACKRATE };
const SLboolean req[2] = { SL_BOOLEAN_FALSE, SL_BOOLEAN_FALSE };
result = (*engineEngine)->CreateAudioPlayer(engineEngine,&uriPlayerObject[cntSOUND],&audioSrc, &audioSnk, 0, ids, req);

and I have parsed the WAVE data myself and loaded format_pcm

SLDataFormat_PCM format_pcm;
format_pcm.formatType = SL_DATAFORMAT_PCM;
char* wavParser = isWAVE(data);
if(wavParser == NULL)
{
    Log("NOT A WAVE!");
    return -1;
}
char* fmtChunk = getChunk("fmt ", data, size);
parsefmtChunk(fmtChunk, &format_pcm);
char* dataChunk = getChunk("data",data, size);
dataChunk += 4;
unsigned int dataSize = *((unsigned int*)dataChunk);
dataChunk += 4;
format_pcm.channelMask = 0;
format_pcm.containerSize = 16;
format_pcm.endianness = SL_BYTEORDER_LITTLEENDIAN;
loc_fd.pAddress = dataChunk;
loc_fd.length = dataSize;

The parsefmtChunk function is

void parsefmtChunk(char* fmtchunk, SLDataFormat_PCM* pcm)
{
char* data = fmtchunk + 8;
unsigned short audioFormat = *((unsigned short*)data);
if(audioFormat != 1)
{
    Log("Not PCM!");
    Log("Reached Line:%d in File %s", __LINE__, __FILE__);
    return;
}
data += 2;
pcm->numChannels = *((unsigned short*)data);
data += 2;
pcm->samplesPerSec = *((unsigned int*)data);
data += 4;
//Byte Rate
data += 4;
//Block Align
data += 2;
//BitsPerSample
pcm->bitsPerSample = *((unsigned short*)data);

(Are Byte Rate and Block Align supposed to be used somehow to fill out the pcm struct?)

but whenever I create the audioplayer I get SL_RESULT_CONTENT_UNSUPPORTED

This is what I log from my parsefmt function Channels:2 samplesPerSec:44100 bitsPerSample:16

agoaj agoaj · Accepted Answer · 2013-09-28T23:52:39

from android-ndk-r8b/docs/opensles/index.html

PCM data format

The PCM data format can be used with buffer queues only.

So SLDataFormat_PCM CANNOT be used with SLDataLocator_Address like I assumed.

I can do what I want with a Buffer Queue instead by using just one big queue like so

bufferqueueitf->Enqueue(bufferqueueitf,dataChunk,dataSize);

Playing PCM WAVE sound from memory with OpenSL on Android

2 Answers