/* returns pointer to buffer */
void* DS_createSoundBuffer(DS_Info* info,
float sampleRate, /* 44100 */
int sampleSizeInBits, /* 16 */
int channels /* 2 */,
int bufferSizeInBytes/* 88200 0.5 sec */)
{
DSBUFFERDESC dsbdesc; //创建DSBUFFERDESC结构体
DSCBUFFERDESC dscbdesc;
HRESULT res;
WAVEFORMATEXTENSIBLE format;
void* buffer;
//TRACE1("Creating secondary buffer for device %d\n", info->deviceID);
//设置主声音缓冲区的波形音频格式
createWaveFormat(&format, (int) sampleRate, channels, info->frameSize / channels * 8, sampleSizeInBits);
/* 2 second secondary buffer */
info->dsBufferSizeInBytes = 2 * ((int) sampleRate) * info->frameSize;
if (bufferSizeInBytes > info->dsBufferSizeInBytes / 2)
{
bufferSizeInBytes = info->dsBufferSizeInBytes / 2;
}
bufferSizeInBytes = (bufferSizeInBytes / info->frameSize) * info->frameSize;
info->bufferSizeInBytes = bufferSizeInBytes;
if (info->isSource)
{
memset(&dsbdesc, 0, sizeof(DSBUFFERDESC)); //清零
dsbdesc.dwSize = sizeof(DSBUFFERDESC); //结构大小
//缓冲区性能标志常量
dsbdesc.dwFlags = DSBCAPS_GETCURRENTPOSITION2 //获取当前位置2
| DSBCAPS_GLOBALFOCUS //有全局焦点的缓冲区
| DSBCAPS_CTRLPAN //声音可以从左声道移动到右声道
| DSBCAPS_CTRLVOLUME //可以改变音量大小
| DSBCAPS_CTRLPOSITIONNOTIFY //可以在缓冲区设置通知的位置
| DSBCAPS_CTRLFX; //设置增强音效特技
dsbdesc.dwBufferBytes = info->dsBufferSizeInBytes;
dsbdesc.lpwfxFormat = (WAVEFORMATEX*) &format; //设置缓冲区格式
res = DEV_PLAY(info->deviceID)->CreateSoundBuffer(&dsbdesc, (LPDIRECTSOUNDBUFFER*) &buffer, NULL); //创建辅助缓冲区
}
else
{
memset(&dscbdesc, 0, sizeof(DSCBUFFERDESC));
dscbdesc.dwSize = sizeof(DSCBUFFERDESC);
dscbdesc.dwFlags = 0;
dscbdesc.dwBufferBytes = info->dsBufferSizeInBytes;
dscbdesc.lpwfxFormat = (WAVEFORMATEX*) &format;
res = DEV_CAPTURE(info->deviceID)->CreateCaptureBuffer(&dscbdesc, (LPDIRECTSOUNDCAPTUREBUFFER*) &buffer, NULL);
}
if (FAILED(res))
{
ERROR1("DS_createSoundBuffer: ERROR: Failed to create sound buffer: %s", TranslateDSError(res));
return NULL;
}
return buffer;
}
int HAE_GetSupportedCaptureFormats(INT32 deviceID,
UINT32 *encodings,
UINT32 *sampleRates,
UINT32 *channels,
UINT32 *bits,
int maxFormats) {
MMRESULT theErr;
WAVEFORMATEXTENSIBLE format;
int rateIndex, channelIndex, bitIndex;
int numSupportedFormats = 0;
/* $$fb 2002-04-10: fix for 4514334: JavaSoundDemo Capture not works on Windows2000 with USB Port */
if (deviceID == 0) {
deviceID = WAVE_MAPPER;
} else {
deviceID--;
}
for (rateIndex = 0; rateIndex < SAMPLERATE_COUNT; rateIndex++) {
for (channelIndex = 0; channelIndex < CHANNELS_COUNT; channelIndex++) {
for (bitIndex = 0; bitIndex < BITS_COUNT; bitIndex++) {
createWaveFormat(&format, sampleRateArray[rateIndex], channelsArray[channelIndex], bitsArray[bitIndex]);
theErr = waveInOpen(0, deviceID, (WAVEFORMATEX*) &format,
0, 0, WAVE_FORMAT_QUERY | WAVE_FORMAT_DIRECT);
if (theErr == MMSYSERR_NOERROR) {
// this format is supported!!
encodings[numSupportedFormats] = PCM;
sampleRates[numSupportedFormats] = sampleRateArray[rateIndex];
channels[numSupportedFormats] = channelsArray[channelIndex];
bits[numSupportedFormats] = bitsArray[bitIndex];
numSupportedFormats++;
if (numSupportedFormats >= maxFormats) return numSupportedFormats;
}
}
}
}
return numSupportedFormats;
}