[vorbis-dev] Streaming buffers/ov_read question
Akshay Dhalwala
akdjr at softhome.net
Thu Jul 5 11:36:16 PDT 2001
Has anyone had experience using ov_read in a thread with streaming
directsound buffers? i have tried the following, but it just produces a
repeating garbage noise. i would appreciate some help.
notes:
test.ogg in my code was a song that i converted to the vorbis format
(Gorillaz - Cling Eastwood)
pcmData is defined like this: char pcmData[4096];
the ogg file and the directsound buffer (lpdsBuffer and vorbisFile) have
already been set up properly.
// code start
void PlaybackThread(void *param)
{
UCHAR *ptr1, *ptr2;
DWORD len1, len2;
long retVal;
int bytes_to_read = 4096;
int writeCursor = 0;
int bufferReadCursor = 0;
bool begPlay = true;
int len1_copy, len2_copy;
HWND hDlg = (HWND)param;
while (!eof)
{
if (bufferReadCursor > 4096)
{
// fill more data into the buffer;
bytes_to_read = 4096;
while (bytes_to_read > 0)
{
retVal = ov_read(&vorbisFile, pcmData, bytes_to_read, 0, 2, 1,
¤tSection);
if (retVal == 0)
{
eof = true;
break;
}
else if (retVal < 0)
{
// Hole in data
// do nothing right now
}
else
{
bytes_to_read = bytes_to_read - retVal;
}
}
bufferReadCursor = 0;
}
if (eof)
break;
lpdsBuffer->Lock(0, 4096, (void **)&ptr1, &len1, (void **)&ptr2, &len2,
DSBLOCK_FROMWRITECURSOR);
if (len1 > (4096 - bufferReadCursor))
len1_copy = 4096 - bufferReadCursor;
else
len1_copy = len1;
memcpy(ptr1, pcmData + bufferReadCursor, len1_copy);
bufferReadCursor += len1_copy;
if (ptr2 != NULL)
{
if (len2 > (4096 - bufferReadCursor))
len2_copy = 4096 - bufferReadCursor;
else
len2_copy = len2;
memcpy(ptr2, pcmData + bufferReadCursor, len2_copy);
bufferReadCursor += len2_copy;
}
lpdsBuffer->Unlock((void **)&ptr1, len1, (void **)&ptr2, len2);
if (begPlay)
{
lpdsBuffer->Play(0, 0, DSBPLAY_LOOPING);
begPlay = false;
}
}
lpdsBuffer->Release();
_endthread();
}
// end code
--- >8 ----
List archives: http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'vorbis-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body. No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.
More information about the Vorbis-dev
mailing list