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Implement the Float32 to UInt8 converters.

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The loopback test now passes cleanly for the first time on my PreSonus FireStudio.
Added tests for clip and dither flag combinations to loopback.
This commit is contained in:
philburk 2011-09-01 22:08:32 +00:00
commit 9cdd56f5b4
4 changed files with 88 additions and 50 deletions
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28
src/common/pa_converters.c
View file

@ -49,8 +49,7 @@
see: "require clipping for dithering sample conversion functions?"
http://www.portaudio.com/trac/ticket/112
@todo implement the converters marked IMPLEMENT ME: Float32_To_UInt8_Dither,
Float32_To_UInt8_Clip, Float32_To_UInt8_DitherClip, Int32_To_Int24_Dither,
@todo implement the converters marked IMPLEMENT ME: Int32_To_Int24_Dither,
Int32_To_UInt8_Dither, Int24_To_Int16_Dither, Int24_To_Int8_Dither,
Int24_To_UInt8_Dither, Int16_To_Int8_Dither, Int16_To_UInt8_Dither
see: "some conversion functions are not implemented in pa_converters.c"
@ -729,8 +728,7 @@ static void Float32_To_Int8_Dither(
{
float *src = (float*)sourceBuffer;
signed char *dest = (signed char*)destinationBuffer;
(void)ditherGenerator; /* unused parameter */
while( count-- )
{
float dither = PaUtil_GenerateFloatTriangularDither( ditherGenerator );
@ -821,12 +819,15 @@ static void Float32_To_UInt8_Dither(
{
float *src = (float*)sourceBuffer;
unsigned char *dest = (unsigned char*)destinationBuffer;
(void)ditherGenerator; /* unused parameter */
while( count-- )
{
/* IMPLEMENT ME */
float dither = PaUtil_GenerateFloatTriangularDither( ditherGenerator );
/* use smaller scaler to prevent overflow when we add the dither */
float dithered = (*src * (126.0f)) + dither;
PaInt32 samp = (PaInt32) dithered;
*dest = (unsigned char) (128 + samp);
src += sourceStride;
dest += destinationStride;
}
@ -845,7 +846,9 @@ static void Float32_To_UInt8_Clip(
while( count-- )
{
/* IMPLEMENT ME */
PaInt32 samp = 128 + (PaInt32)(*src * (127.0f));
PA_CLIP_( samp, 0x0000, 0x00FF );
*dest = (unsigned char) samp;
src += sourceStride;
dest += destinationStride;
@ -865,7 +868,12 @@ static void Float32_To_UInt8_DitherClip(
while( count-- )
{
/* IMPLEMENT ME */
float dither = PaUtil_GenerateFloatTriangularDither( ditherGenerator );
/* use smaller scaler to prevent overflow when we add the dither */
float dithered = (*src * (126.0f)) + dither;
PaInt32 samp = 128 + (PaInt32) dithered;
PA_CLIP_( samp, 0x0000, 0x00FF );
*dest = (unsigned char) samp;
src += sourceStride;
dest += destinationStride;

10
src/hostapi/coreaudio/pa_mac_core.c
View file

@ -1009,6 +1009,10 @@ static OSStatus UpdateSampleRateFromDeviceProperty( PaMacCoreStream *stream, Aud
static OSStatus AudioDevicePropertyActualSampleRateListenerProc( AudioDeviceID inDevice, UInt32 inChannel, Boolean isInput, AudioDevicePropertyID inPropertyID, void *inClientData )
{
PaMacCoreStream *stream = (PaMacCoreStream*)inClientData;
// Make sure the callback is operating on a stream that is still valid!
assert( stream->streamRepresentation.magic == PA_STREAM_MAGIC );
OSStatus osErr = UpdateSampleRateFromDeviceProperty( stream, inDevice, isInput );
if( osErr == noErr )
{
@ -1034,6 +1038,10 @@ static OSStatus AudioDevicePropertyGenericListenerProc( AudioDeviceID inDevice,
{
OSStatus osErr = noErr;
PaMacCoreStream *stream = (PaMacCoreStream*)inClientData;
// Make sure the callback is operating on a stream that is still valid!
assert( stream->streamRepresentation.magic == PA_STREAM_MAGIC );
PaMacCoreDeviceProperties *deviceProperties = isInput ? &stream->inputProperties : &stream->outputProperties;
UInt32 *valuePtr = NULL;
switch( inPropertyID )
@ -2107,7 +2115,7 @@ static OSStatus AudioIOProc( void *inRefCon,
PaMacCoreStream *stream = (PaMacCoreStream*)inRefCon;
const bool isRender = inBusNumber == OUTPUT_ELEMENT;
int callbackResult = paContinue ;
double hostTimeStampInPaTime = HOST_TIME_TO_PA_TIME(inTimeStamp->mHostTime);
double hostTimeStampInPaTime = HOST_TIME_TO_PA_TIME(inTimeStamp->mHostTime);
VVDBUG(("AudioIOProc()\n"));