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IOAudioEngineMixer.cpp
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IOAudioEngineMixer.cpp
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/*
* Copyright (c) 1998-2014 Apple Computer, Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* The contents of this file constitute Original Code as defined in and
* are subject to the Apple Public Source License Version 1.1 (the
* "License"). You may not use this file except in compliance with the
* License. Please obtain a copy of the License at
* http://www.apple.com/publicsource and read it before using this file.
*
* This Original Code and all software distributed under the License are
* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
* License for the specific language governing rights and limitations
* under the License.
*
* @APPLE_LICENSE_HEADER_END@
*/
#include "IOAudioDebug.h"
#include "IOAudioEngine.h"
#include "IOAudioStream.h"
#include "IOAudioTypes.h"
#include <vecLib/vecLib.h> // <rdar://14058728>
IOReturn IOAudioEngine::mixOutputSamples(const void *sourceBuf, void *mixBuf, UInt32 firstSampleFrame, UInt32 numSampleFrames, const IOAudioStreamFormat *streamFormat, IOAudioStream *audioStream)
{
IOReturn result = kIOReturnBadArgument;
if (sourceBuf && mixBuf)
{
const float * floatSource1Buf;
const float * floatSource2Buf;
float * floatMixBuf;
UInt32 numSamplesLeft = numSampleFrames * streamFormat->fNumChannels;
__darwin_size_t numSamps = numSamplesLeft;
floatMixBuf = &(((float *)mixBuf)[firstSampleFrame * streamFormat->fNumChannels]);
floatSource2Buf = floatMixBuf;
floatSource1Buf = (const float *)sourceBuf;
__darwin_ptrdiff_t strideOne=1, strideTwo=1, resultStride=1;
vDSP_vadd(floatSource1Buf, strideOne, floatSource2Buf, strideTwo, floatMixBuf, resultStride, numSamps);
result = kIOReturnSuccess;
}
return result;
}