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/*
File: ACSimpleCodec.cpp
Abstract: ACSimpleCodec.h
Version: 1.1
Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple
Inc. ("Apple") in consideration of your agreement to the following
terms, and your use, installation, modification or redistribution of
this Apple software constitutes acceptance of these terms. If you do
not agree with these terms, please do not use, install, modify or
redistribute this Apple software.
In consideration of your agreement to abide by the following terms, and
subject to these terms, Apple grants you a personal, non-exclusive
license, under Apple's copyrights in this original Apple software (the
"Apple Software"), to use, reproduce, modify and redistribute the Apple
Software, with or without modifications, in source and/or binary forms;
provided that if you redistribute the Apple Software in its entirety and
without modifications, you must retain this notice and the following
text and disclaimers in all such redistributions of the Apple Software.
Neither the name, trademarks, service marks or logos of Apple Inc. may
be used to endorse or promote products derived from the Apple Software
without specific prior written permission from Apple. Except as
expressly stated in this notice, no other rights or licenses, express or
implied, are granted by Apple herein, including but not limited to any
patent rights that may be infringed by your derivative works or by other
works in which the Apple Software may be incorporated.
The Apple Software is provided by Apple on an "AS IS" basis. APPLE
MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION
THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND
OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS.
IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL
OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION,
MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED
AND WHETHER UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE),
STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
Copyright (C) 2014 Apple Inc. All Rights Reserved.
*/
//=============================================================================
// Includes
//=============================================================================
#include "ACSimpleCodec.h"
#include <string.h>
//=============================================================================
// ACSimpleCodec
//=============================================================================
static const UInt32 kBufferPad = 64; // this is used to prevent end from passing start.
ACSimpleCodec::ACSimpleCodec(UInt32 inInputBufferByteSize, AudioComponentInstance inInstance)
:
ACBaseCodec(inInstance),
mInputBuffer(NULL),
mInputBufferByteSize(inInputBufferByteSize+kBufferPad),
mInputBufferStart(0),
mInputBufferEnd(0)
{
}
ACSimpleCodec::~ACSimpleCodec()
{
delete[] mInputBuffer;
}
void ACSimpleCodec::Initialize(const AudioStreamBasicDescription* inInputFormat, const AudioStreamBasicDescription* inOutputFormat, const void* inMagicCookie, UInt32 inMagicCookieByteSize)
{
ReallocateInputBuffer(mInputBufferByteSize - kBufferPad);
// By definition CBR has this greater than 0. We must avoid a div by 0 error in AppendInputData()
// Note this will cause us to fail initialization which is intended
if (mInputFormat.mBytesPerPacket == 0)
{
CODEC_THROW(kAudioCodecUnsupportedFormatError);
}
ACBaseCodec::Initialize(inInputFormat, inOutputFormat, inMagicCookie, inMagicCookieByteSize);
}
void ACSimpleCodec::Uninitialize()
{
// get rid of the buffer
delete[] mInputBuffer;
mInputBuffer = NULL;
// reset the ring buffer state
mInputBufferStart = 0;
mInputBufferEnd = 0;
ACBaseCodec::Uninitialize();
}
void ACSimpleCodec::Reset()
{
// clear the entire input buffer
if (mInputBuffer) { // could be called before allocated.
memset(mInputBuffer, 0, mInputBufferByteSize);
}
// reset the ring buffer state
mInputBufferStart = 0;
mInputBufferEnd = 0;
ACBaseCodec::Reset();
}
UInt32 ACSimpleCodec::GetInputBufferByteSize() const
{
return mInputBufferByteSize - kBufferPad; // minus kBufferPad to prevent end moving past start
}
UInt32 ACSimpleCodec::GetUsedInputBufferByteSize() const
{
UInt32 theAnswer = 0;
// this object uses a ring buffer
if(mInputBufferStart <= mInputBufferEnd)
{
// the active region is contiguous
theAnswer = mInputBufferEnd - mInputBufferStart;
}
else
{
// the active region wraps around
theAnswer = (mInputBufferByteSize - mInputBufferStart) + mInputBufferEnd;
}
return theAnswer;
}
void ACSimpleCodec::AppendInputData(const void* inInputData, UInt32& ioInputDataByteSize, UInt32& ioNumberPackets, const AudioStreamPacketDescription* inPacketDescription)
{
// this buffer handling code doesn't care about such things as the packet descriptions
if(!mIsInitialized) CODEC_THROW(kAudioCodecStateError);
// this is a ring buffer we're dealing with, so we need to set up a few things
UInt32 theUsedByteSize = GetUsedInputBufferByteSize();
UInt32 theAvailableByteSize = GetInputBufferByteSize() - theUsedByteSize;
UInt32 theMaxAvailableInputBytes = ioInputDataByteSize; // we can't consume more than we get
const Byte* theInputData = static_cast<const Byte*>(inInputData);
// >>jamesmcc: added this because ioNumberPackets was not being updated if less was taken than given.
// THIS ASSUMES CBR!
UInt32 bytesPerPacketOfInput = mInputFormat.mBytesPerPacket;
UInt32 theAvailablePacketSize = theAvailableByteSize / bytesPerPacketOfInput;
UInt32 minPacketSize = ioNumberPackets < theAvailablePacketSize ? ioNumberPackets : theAvailablePacketSize;
UInt32 minByteSize = minPacketSize * bytesPerPacketOfInput;
// we can copy only as much data as there is or up to how much space is availiable
ioNumberPackets = minPacketSize;
ioInputDataByteSize = minByteSize;
// ioInputDataByteSize had better be <= to theMaxAvailableInputBytes or we're screwed
if (ioInputDataByteSize > theMaxAvailableInputBytes)
{
CODEC_THROW(kAudioCodecStateError);
}
// <<jamesmcc
// now we have to copy the data taking into account the wrap around and where the start is
if(mInputBufferEnd + ioInputDataByteSize < mInputBufferByteSize)
{
// no wrap around here
memcpy(mInputBuffer + mInputBufferEnd, theInputData, ioInputDataByteSize);
// adjust the end point
mInputBufferEnd += ioInputDataByteSize;
}
else
{
// the copy will wrap
// copy the first part
UInt32 theBeforeWrapByteSize = mInputBufferByteSize - mInputBufferEnd;
memcpy(mInputBuffer + mInputBufferEnd, theInputData, theBeforeWrapByteSize);
// and the rest
UInt32 theAfterWrapByteSize = ioInputDataByteSize - theBeforeWrapByteSize;
memcpy(mInputBuffer, theInputData + theBeforeWrapByteSize, theAfterWrapByteSize);
// adjust the end point
mInputBufferEnd = theAfterWrapByteSize;
}
}
void ACSimpleCodec::ZeroPadInputData(UInt32& ioNumberPackets, const AudioStreamPacketDescription* inPacketDescription)
{
// this buffer handling code doesn't care about such things as the packet descriptions
if(!mIsInitialized) CODEC_THROW(kAudioCodecStateError);
// this is a ring buffer we're dealing with, so we need to set up a few things
UInt32 theUsedByteSize = GetUsedInputBufferByteSize();
UInt32 theAvailableByteSize = GetInputBufferByteSize() - theUsedByteSize;
// >>jamesmcc: added this because ioNumberPackets was not being updated if less was taken than given.
// THIS ASSUMES CBR!
UInt32 bytesPerPacketOfInput = mInputFormat.mBytesPerPacket;
UInt32 theAvailablePacketSize = theAvailableByteSize / bytesPerPacketOfInput;
UInt32 minPacketSize = ioNumberPackets < theAvailablePacketSize ? ioNumberPackets : theAvailablePacketSize;
UInt32 minByteSize = minPacketSize * bytesPerPacketOfInput;
// we can copy only as much data as there is or up to how much space is availiable
ioNumberPackets = minPacketSize;
// <<jamesmcc
// now we have to copy the data taking into account the wrap around and where the start is
if(mInputBufferEnd + minByteSize < mInputBufferByteSize)
{
// no wrap around here
memset(mInputBuffer + mInputBufferEnd, 0, minByteSize);
// adjust the end point
mInputBufferEnd += minByteSize;
}
else
{
// the copy will wrap
// copy the first part
UInt32 theBeforeWrapByteSize = mInputBufferByteSize - mInputBufferEnd;
memset(mInputBuffer + mInputBufferEnd, 0, theBeforeWrapByteSize);
// and the rest
UInt32 theAfterWrapByteSize = minByteSize - theBeforeWrapByteSize;
memset(mInputBuffer, 0, theAfterWrapByteSize);
// adjust the end point
mInputBufferEnd = theAfterWrapByteSize;
}
}
void ACSimpleCodec::ConsumeInputData(UInt32 inConsumedByteSize)
{
// this is a convenience routine to make maintaining the ring buffer state easy
UInt32 theContiguousRange = GetInputBufferContiguousByteSize();
if(inConsumedByteSize > GetUsedInputBufferByteSize()) CODEC_THROW(kAudioCodecUnspecifiedError);
if(inConsumedByteSize <= theContiguousRange)
{
// the region to consume doesn't wrap
// figure out how much to consume
inConsumedByteSize = (theContiguousRange < inConsumedByteSize) ? theContiguousRange : inConsumedByteSize;
// clear the consumed bits
memset(mInputBuffer + mInputBufferStart, 0, inConsumedByteSize);
// adjust the start
mInputBufferStart += inConsumedByteSize;
}
else
{
// the region to consume will wrap
// clear the bits to the end of the buffer
memset(mInputBuffer + mInputBufferStart, 0, theContiguousRange);
// now clear the bits left from the start
memset(mInputBuffer, 0, inConsumedByteSize - theContiguousRange);
// adjust the start
mInputBufferStart = inConsumedByteSize - theContiguousRange;
}
}
Byte* ACSimpleCodec::GetBytes(UInt32& ioNumberBytes) const
{
// if a client's algorithm has to have contiguous data and mInputBuffer wraps, then someone has to make a copy.
// I can do it more efficiently than the client.
if(!mIsInitialized) CODEC_THROW(kAudioCodecStateError);
UInt32 theUsedByteSize = GetUsedInputBufferByteSize();
//UInt32 theAvailableByteSize = GetInputBufferByteSize() - theUsedByteSize;
if (ioNumberBytes > theUsedByteSize) ioNumberBytes = theUsedByteSize;
SInt32 leftOver = mInputBufferStart + ioNumberBytes - mInputBufferByteSize;
if(leftOver > 0)
{
// need to copy beginning of buffer to the end.
// We cleverly over allocated our buffer space to make this possible.
memmove(mInputBuffer + mInputBufferByteSize, mInputBuffer, leftOver);
}
return GetInputBufferStart();
}
void ACSimpleCodec::ReallocateInputBuffer(UInt32 inInputBufferByteSize)
{
mInputBufferByteSize = inInputBufferByteSize + kBufferPad;
// toss the old buffer
delete[] mInputBuffer;
mInputBuffer = NULL;
// allocate the new one
// allocate extra in order to allow making contiguous data.
UInt32 allocSize = 2*inInputBufferByteSize + kBufferPad;
mInputBuffer = new Byte[allocSize];
memset(mInputBuffer, 0, allocSize);
// reset the ring buffer state
mInputBufferStart = 0;
mInputBufferEnd = 0;
}
void ACSimpleCodec::GetPropertyInfo(AudioCodecPropertyID inPropertyID, UInt32& outPropertyDataSize, Boolean& outWritable)
{
switch(inPropertyID)
{
case kAudioCodecPropertyInputBufferSize:
outPropertyDataSize = SizeOf32(UInt32);
outWritable = true;
break;
default:
ACBaseCodec::GetPropertyInfo(inPropertyID, outPropertyDataSize, outWritable);
break;
}
}
void ACSimpleCodec::SetProperty(AudioCodecPropertyID inPropertyID, UInt32 inPropertyDataSize, const void* inPropertyData)
{
switch(inPropertyID)
{
case kAudioCodecPropertyInputBufferSize:
if(inPropertyDataSize == sizeof(UInt32))
{
ReallocateInputBuffer(*reinterpret_cast<const UInt32*>(inPropertyData));
}
else
{
CODEC_THROW(kAudioCodecBadPropertySizeError);
}
break;
default:
ACBaseCodec::SetProperty(inPropertyID, inPropertyDataSize, inPropertyData);
break;
}
}
|