java Android OpenSL“pAudioSrc:data format 2 not allowed”拒绝SL_DATAFORMAT_PCM？

Question

我正在尝试创建一个AudioPlayer带有缓冲队列源和outputmix接收器。我已经用与ndk示例中所示非常相似的pcm格式配置了源代码，但是OpenSL拒绝了SL_DATAFORMAT_PCM（“数据格式2”）。这对我来说毫无意义

以下是错误（在三星Galaxy S2上）：

02-27 15:43:47.315: E/libOpenSLES(12681): pAudioSrc: data format 2 not allowed
02-27 15:43:47.315: W/libOpenSLES(12681): Leaving Engine::CreateAudioPlayer (SL_RESULT_CONTENT_UNSUPPORTED)

以下是相关代码：

SLuint32 channels = 2;
SLuint32 speakers = SL_SPEAKER_FRONT_LEFT | SL_SPEAKER_FRONT_RIGHT;
SLuint32 sr = SL_SAMPLINGRATE_48;

//...
SLDataFormat_PCM format_pcm = {
    SL_DATAFORMAT_PCM,
    channels,
    sr,
    SL_PCMSAMPLEFORMAT_FIXED_16,
    SL_PCMSAMPLEFORMAT_FIXED_16,
    speakers,
    SL_BYTEORDER_LITTLEENDIAN
};

// Configure audio player source
SLDataLocator_AndroidBufferQueue loc_bufq =
    {SL_DATALOCATOR_ANDROIDBUFFERQUEUE, 2};
SLDataSource audioSrc = {&loc_bufq, &format_pcm};

// configure audio player sink
SLDataLocator_OutputMix loc_outmix =
    {SL_DATALOCATOR_OUTPUTMIX, outputMixObject};
SLDataSink audioSnk = {&loc_outmix, NULL};

// create audio player
const SLInterfaceID iidsOutPlayer[] = {SL_IID_ANDROIDBUFFERQUEUESOURCE};
const SLboolean reqsOutPlayer[] = {SL_BOOLEAN_TRUE};
result = (*engineItf)->CreateAudioPlayer(
                        engineItf,
                        &(outPlayerObject),
                        &audioSrc, &audioSnk,
                        1, iidsOutPlayer,reqsOutPlayer);

有人知道这是什么原因吗？谢谢

Answer 1

结果是我需要使用SLDataLocator_AndroidSimpleBufferQueue而不是SLDataLocator_AndroidBufferQueue

Answer 2

可能是您的设备不支持音频采样率。试试SL_SAMPLINGRATE_8 而不是SL_SAMPLINGRATE_48或选择其他设备（Nexus 4/HTC One）进行测试

如果您在语音通信时听到失真的声音，请增加记录器缓冲区大小，您也可以尝试更改采样率。其他采样率选项有：SL_SAMPLINGRATE_16、SL_SAMPLINGRATE_32、SL_SAMPLINGRATE_44_1等

每个android设备都有一个特定/首选的缓冲区大小和采样率。您可以从下面的java代码段中获得首选的缓冲区大小和采样率。请注意，audioManager。getProperty（）不适用于API级别<；十七,

AudioManager audioManager = (AudioManager) this.getSystemService(Context.AUDIO_SERVICE);
String rate = audioManager.getProperty(AudioManager.PROPERTY_OUTPUT_SAMPLE_RATE);
String size = audioManager.getProperty(AudioManager.PROPERTY_OUTPUT_FRAMES_PER_BUFFER);
Log.d("Buffer Size and sample rate", "Size :" + size + " & Rate: " + rate);