poke/alac/codec/ALACEncoder.h
2023-02-12 09:13:40 +00:00

92 lines
3 KiB
C++

/*
* Copyright (c) 2011 Apple Inc. All rights reserved.
*
* @APPLE_APACHE_LICENSE_HEADER_START@
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* @APPLE_APACHE_LICENSE_HEADER_END@
*/
/*
File: ALACEncoder.h
*/
#pragma once
#include <stdint.h>
#include "ALACAudioTypes.h"
struct BitBuffer;
class ALACEncoder
{
public:
ALACEncoder();
virtual ~ALACEncoder();
virtual int32_t Encode(AudioFormatDescription theInputFormat, AudioFormatDescription theOutputFormat,
unsigned char * theReadBuffer, unsigned char * theWriteBuffer, int32_t * ioNumBytes);
virtual int32_t Finish( );
void SetFastMode( bool fast ) { mFastMode = fast; };
// this must be called *before* InitializeEncoder()
void SetFrameSize( uint32_t frameSize ) { mFrameSize = frameSize; };
void GetConfig( ALACSpecificConfig & config );
uint32_t GetMagicCookieSize(uint32_t inNumChannels);
void GetMagicCookie( void * config, uint32_t * ioSize );
virtual int32_t InitializeEncoder(AudioFormatDescription theOutputFormat);
protected:
virtual void GetSourceFormat( const AudioFormatDescription * source, AudioFormatDescription * output );
int32_t EncodeStereo( struct BitBuffer * bitstream, void * input, uint32_t stride, uint32_t channelIndex, uint32_t numSamples );
int32_t EncodeStereoFast( struct BitBuffer * bitstream, void * input, uint32_t stride, uint32_t channelIndex, uint32_t numSamples );
int32_t EncodeStereoEscape( struct BitBuffer * bitstream, void * input, uint32_t stride, uint32_t numSamples );
int32_t EncodeMono( struct BitBuffer * bitstream, void * input, uint32_t stride, uint32_t channelIndex, uint32_t numSamples );
// ALAC encoder parameters
int16_t mBitDepth;
bool mFastMode;
// encoding state
int16_t mLastMixRes[kALACMaxChannels];
// encoding buffers
int32_t * mMixBufferU;
int32_t * mMixBufferV;
int32_t * mPredictorU;
int32_t * mPredictorV;
uint16_t * mShiftBufferUV;
uint8_t * mWorkBuffer;
// per-channel coefficients buffers
int16_t mCoefsU[kALACMaxChannels][kALACMaxSearches][kALACMaxCoefs];
int16_t mCoefsV[kALACMaxChannels][kALACMaxSearches][kALACMaxCoefs];
// encoding statistics
uint32_t mTotalBytesGenerated;
uint32_t mAvgBitRate;
uint32_t mMaxFrameBytes;
uint32_t mFrameSize;
uint32_t mMaxOutputBytes;
uint32_t mNumChannels;
uint32_t mOutputSampleRate;
};