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/*
* Copyright (c) 2011 Apple Inc. All rights reserved.
* Copyright (C) 2012-2014 Erik de Castro Lopo <erikd@mega-nerd.com>
*
* @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: alac_codec.h
*/
#ifndef ALAC_CODEC_H
#define ALAC_CODEC_H
#include <stdint.h>
#include "ALACAudioTypes.h"
#define ALAC_FRAME_LENGTH 4096
struct BitBuffer ;
typedef struct alac_decoder_s
{
// decoding parameters (public for use in the analyzer)
ALACSpecificConfig mConfig ;
uint16_t mActiveElements ;
// decoding buffers
int32_t mMixBufferU [ALAC_FRAME_LENGTH] ;
int32_t mMixBufferV [ALAC_FRAME_LENGTH] ;
union
{
int32_t mPredictor [ALAC_FRAME_LENGTH] ;
uint16_t mShiftBuffer [ALAC_FRAME_LENGTH] ;
} ;
} ALAC_DECODER ;
typedef struct alac_encoder_s
{
// ALAC encoder parameters
int16_t mBitDepth ;
// encoding state
int16_t mLastMixRes [kALACMaxChannels] ;
int32_t mFastMode ;
// encoding buffers
int32_t mMixBufferU [ALAC_FRAME_LENGTH] ;
int32_t mMixBufferV [ALAC_FRAME_LENGTH] ;
int32_t mPredictorU [ALAC_FRAME_LENGTH] ;
int32_t mPredictorV [ALAC_FRAME_LENGTH] ;
uint16_t mShiftBufferUV [2 * ALAC_FRAME_LENGTH] ;
uint8_t mWorkBuffer [4 * ALAC_FRAME_LENGTH] ;
// 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 ;
} ALAC_ENCODER ;
int32_t alac_decoder_init (ALAC_DECODER *p, void * inMagicCookie, uint32_t inMagicCookieSize) ;
int32_t alac_encoder_init (ALAC_ENCODER *p, uint32_t samplerate, uint32_t channels, uint32_t format_flags, uint32_t frameSize) ;
int32_t alac_decode (ALAC_DECODER *, struct BitBuffer * bits, int32_t * sampleBuffer,
uint32_t numSamples, uint32_t numChannels, uint32_t * outNumSamples) ;
int32_t alac_encode (ALAC_ENCODER *p, uint32_t numChannels, uint32_t numSamples,
int32_t * theReadBuffer, unsigned char * theWriteBuffer,
uint32_t * ioNumBytes) ;
void alac_set_fastmode (ALAC_ENCODER * p, int32_t fast) ;
uint32_t alac_get_magic_cookie_size (uint32_t inNumChannels) ;
void alac_get_magic_cookie (ALAC_ENCODER *p, void * config, uint32_t * ioSize) ;
void alac_get_source_format (ALAC_ENCODER *p, const AudioFormatDescription * source, AudioFormatDescription * output) ;
#endif
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