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Fixed bug where I was calling the wrong function to calculate

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the minimum number of user buffers. This resulted in a too conservative,
ie. too high, latency.
This commit is contained in:
philburk 2002-04-18 19:40:11 +00:00
commit 687dfcbe4e
1 changed files with 26 additions and 8 deletions
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34
pa_mac/pa_mac.c
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@ -42,7 +42,12 @@
PLB20010907 - Pass unused event to WaitNextEvent to prevent Mac OSX crash. Thanks Dominic Mazzoni.
PLB20010908 - Use requested number of input channels. Thanks Dominic Mazzoni.
PLB20011009 - Use NewSndCallBackUPP() for CARBON
PLB20020417 - I used to call Pa_GetMinNumBuffers() which doesn't take into account the
variable minFramesPerHostBuffer. Now I call PaMac_GetMinNumBuffers() which will
gove lower latency when virtual memory is turned off.
Thanks Kristoffer Jensen and Georgios Marentakis for spotting this bug.
*/
/*
COMPATIBILITY
This Macintosh implementation is designed for use with Mac OS 7, 8 and
@ -72,6 +77,7 @@ O- Determine default devices somehow.
#include <string.h>
#include <memory.h>
#include <math.h>
/* Mac specific includes */
#include "OSUtils.h"
#include <MacTypes.h>
@ -84,6 +90,7 @@ O- Determine default devices somehow.
#include <DateTimeUtils.h>
#include <Timer.h>
#include <Gestalt.h>
#include "portaudio.h"
#include "pa_host.h"
#include "pa_trace.h"
@ -942,8 +949,8 @@ int Mac_IsVirtualMemoryOn( void )
}
/*******************************************************************
* Determine number of WAVE Buffers
* and how many User Buffers we can put into each WAVE buffer.
* Determine number of host Buffers
* and how many User Buffers we can put into each host buffer.
*/
static void PaHost_CalcNumHostBuffers( internalPortAudioStream *past )
{
@ -954,16 +961,23 @@ static void PaHost_CalcNumHostBuffers( internalPortAudioStream *past )
int32 userBuffersPerHostBuffer;
int32 framesPerHostBuffer;
int32 numHostBuffers;
/* Calculate minimum and maximum sizes based on timing and sample rate. */
minFramesPerHostBuffer = pahsc->pahsc_MinFramesPerHostBuffer;
minFramesPerHostBuffer = (minFramesPerHostBuffer + 7) & ~7;
DBUG(("PaHost_CalcNumHostBuffers: minFramesPerHostBuffer = %d\n", minFramesPerHostBuffer ));
/* Determine number of user buffers based on minimum latency. */
minNumBuffers = Pa_GetMinNumBuffers( past->past_FramesPerUserBuffer, past->past_SampleRate );
/* PLB20020417 I used to call Pa_GetMinNumBuffers() which doesn't take into account the
** variable minFramesPerHostBuffer. Now I call PaMac_GetMinNumBuffers() which will
** gove lower latency when virtual memory is turned off. */
/* minNumBuffers = Pa_GetMinNumBuffers( past->past_FramesPerUserBuffer, past->past_SampleRate ); WRONG */
minNumBuffers = PaMac_GetMinNumBuffers( minFramesPerHostBuffer, past->past_FramesPerUserBuffer, past->past_SampleRate );
past->past_NumUserBuffers = ( minNumBuffers > past->past_NumUserBuffers ) ? minNumBuffers : past->past_NumUserBuffers;
DBUG(("PaHost_CalcNumHostBuffers: min past_NumUserBuffers = %d\n", past->past_NumUserBuffers ));
minTotalFrames = past->past_NumUserBuffers * past->past_FramesPerUserBuffer;
/* We cannot make the WAVE buffers too small because they may not get serviced quickly enough. */
/* We cannot make the buffers too small because they may not get serviced quickly enough. */
if( (int32) past->past_FramesPerUserBuffer < minFramesPerHostBuffer )
{
userBuffersPerHostBuffer =
@ -975,16 +989,17 @@ static void PaHost_CalcNumHostBuffers( internalPortAudioStream *past )
userBuffersPerHostBuffer = 1;
}
framesPerHostBuffer = past->past_FramesPerUserBuffer * userBuffersPerHostBuffer;
/* Calculate number of WAVE buffers needed. Round up to cover minTotalFrames. */
/* Calculate number of host buffers needed. Round up to cover minTotalFrames. */
numHostBuffers = (minTotalFrames + framesPerHostBuffer - 1) / framesPerHostBuffer;
/* Make sure we have anough WAVE buffers. */
/* Make sure we have enough host buffers. */
if( numHostBuffers < PA_MIN_NUM_HOST_BUFFERS)
{
numHostBuffers = PA_MIN_NUM_HOST_BUFFERS;
}
else
{
/* If we have too many WAVE buffers, try to put more user buffers in a wave buffer. */
/* If we have too many host buffers, try to put more user buffers in a host buffer. */
while(numHostBuffers > PA_MAX_NUM_HOST_BUFFERS)
{
userBuffersPerHostBuffer += 1;
@ -1219,6 +1234,9 @@ PaError PaHost_CloseStream( internalPortAudioStream *past )
/*************************************************************************/
int Pa_GetMinNumBuffers( int framesPerUserBuffer, double sampleRate )
{
/* We use the MAC_VIRTUAL_FRAMES_PER_BUFFER because we might be recording.
** This routine doesn't have enough information to determine the best value
** and is being depracated. */
return PaMac_GetMinNumBuffers( MAC_VIRTUAL_FRAMES_PER_BUFFER, framesPerUserBuffer, sampleRate );
}
/*************************************************************************/