Soundpool:样本还没有准备好

Question

我已将Android中的默认媒体框架从StageFright更改为GSTREAMER。这样做是为了使我们的项目灵活。

但是，当我运行一些APK时，应用程序的所有声音在应用程序开始时都会播放，并且在显示错误的"示例＃不准备就绪"之后不会播放。例如，在应用婴儿钢琴中，启动应用程序时弹奏钢琴音节的声音正在弹奏，当我进入弹奏模式后实际单击钢琴时，它没有弹奏。

>

我认为的问题是，当声音被加载到Soundpool中时，创建了Gstreamer MediaPlayer对象并播放它，并且在应用程序的开头完成。

在日志中显示，样本通道计数（0）超出范围。它正在从下面的部分中从soundpoool.cpp文件中进行。

status_t Sample::doLoad() {
    uint32_t sampleRate;
    int numChannels;
    int format;
    sp<IMemory> p;
    LOGW("Start decode");
    if (mUrl) {
        p = MediaPlayer::decode(mUrl, &sampleRate, &numChannels, &format);
    } else {
        p = MediaPlayer::decode(mFd, mOffset, mLength, &sampleRate, &numChannels, &format);
        LOGW("close(%d)", mFd);
        ::close(mFd);
        mFd = -1;
    }
    if (p == 0) {
        LOGE("Unable to load sample: %s", mUrl);
        return -1;
    }
    LOGW("pointer = %p, size = %u, sampleRate = %u, numChannels = %d",
            p->pointer(), p->size(), sampleRate, numChannels);
    if (sampleRate > kMaxSampleRate) {
       LOGE("Sample rate (%u) out of range", sampleRate);
       return - 1;
    }
    if ((numChannels < 1) || (numChannels > 2)) {
        LOGE("Sample channel count (%d) out of range", numChannels);
        return - 1;
    }
    //_dumpBuffer(p->pointer(), p->size());
    uint8_t* q = static_cast<uint8_t*>(p->pointer()) + p->size() - 10;
    //_dumpBuffer(q, 10, 10, false);
    mData = p;
    mSize = p->size();
    mSampleRate = sampleRate;
    mNumChannels = numChannels;
    mFormat = format;
    mState = READY;
    return 0; }

和MediaPlayerService Decode函数从下面的"代码"部分返回所有值为null

sp<IMemory> MediaPlayerService::decode(int fd, int64_t offset, int64_t length, uint32_t *pSampleRate, int* pNumChannels, int* pFormat)
{
    LOGD("decode(%d, %lld, %lld)", fd, offset, length);
    sp<MemoryBase> mem;
    sp<MediaPlayerBase> player;
    player_type playerType = getPlayerType(fd, offset, length);
    LOGD("player type = %d", playerType);
    // create the right type of player
    sp<AudioCache> cache = new AudioCache("decode_fd");
    player = android::createPlayer(playerType, cache.get(), cache->notify);
    if (player == NULL) goto Exit;
    if (player->hardwareOutput()) goto Exit;
    static_cast<MediaPlayerInterface*>(player.get())->setAudioSink(cache);
    // set data source
    if (player->setDataSource(fd, offset, length) != NO_ERROR) goto Exit;
    LOGD("prepare");
    player->prepareAsync();
    LOGD("wait for prepare");
    if (cache->wait() != NO_ERROR) goto Exit;
    LOGD("start");
    player->start();
    LOGD("wait for playback complete");
    if (cache->wait() != NO_ERROR) goto Exit;
    mem = new MemoryBase(cache->getHeap(), 0, cache->size());
    *pSampleRate = cache->sampleRate();//Nes
    *pNumChannels = cache->channelCount();
    *pFormat = cache->format();
    LOGD("return memory @ %p, sampleRate=%u, channelCount = %d, format = %d", mem->pointer(), *pSampleRate, *pNumChannels, *pFormat);
Exit:
    if (player != 0) player->reset();
    ::close(fd);
    return mem;
}

采样，频道等有值0从此功能返回。

在此之后播放样品时，它显示了错误"示例＃未准备就绪"

int SoundPool::play(int sampleID, float leftVolume, float rightVolume,
        int priority, int loop, float rate)
{
    LOGW("sampleID=%d, leftVolume=%f, rightVolume=%f, priority=%d, loop=%d, rate=%f",
            sampleID, leftVolume, rightVolume, priority, loop, rate);
    sp<Sample> sample;
    SoundChannel* channel;
    int channelID;
    // scope for lock
    {
        Mutex::Autolock lock(&mLock);
        // is sample ready?
        sample = findSample(sampleID);
        if ((sample == 0) || (sample->state() != Sample::READY)) {
            LOGW("  sample %d not READY", sampleID);
            return 0;
        }
        dump();
        // allocate a channel
        channel = allocateChannel(priority);
        // no channel allocated - return 0
        if (!channel) {
            LOGW("No channel allocated");
            return 0;
        }
        channelID = ++mNextChannelID;
    }
    LOGW("channel state = %d", channel->state());
    channel->play(sample, channelID, leftVolume, rightVolume, priority, loop, rate);
    return channelID;
}

是否有解决此问题的解决方案。Plz帮助..

Answer 1

您也可以使用此methode

public void loadSound (String strSound, int stream) {
     boolean loaded = false;
     mSoundPool.setOnLoadCompleteListener(new OnLoadCompleteListener() {
            @Override
            public void onLoadComplete(SoundPool soundPool, int sampleId,
                    int status) {
                mSoundPool.play(stream, streamVolume, streamVolume, 1, LOOP_1_TIME, 1f);
            }
        });
    try {
          stream= mSoundPool.load(aMan.openFd(strSound), 1);
        } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

Answer 2

尚未准备就绪的样本通常表示尚未加载它，即仍在加载。（也许您切换到的框架可能会加载更长的时间。）

您应该订阅其onLoadCompleteListener，当您收到回调时，声音就可以播放了。在此之前，它将无法播放。

Answer 3

i对于Android 2.0也有相同的问题，并通过使用.ogg格式而不是.mp3格式来解决我使用的声音。我希望这能解决您的问题。