1/* 2 * Copyright (c) 2011 Apple Inc. All rights reserved. 3 * 4 * @APPLE_APACHE_LICENSE_HEADER_START@ 5 * 6 * Licensed under the Apache License, Version 2.0 (the "License") ; 7 * you may not use this file except in compliance with the License. 8 * You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, software 13 * distributed under the License is distributed on an "AS IS" BASIS, 14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 15 * See the License for the specific language governing permissions and 16 * limitations under the License. 17 * 18 * @APPLE_APACHE_LICENSE_HEADER_END@ 19 */ 20 21/* 22 File: ALACEncoder.h 23*/ 24 25#pragma once 26 27#include <stdint.h> 28 29#include "ALACAudioTypes.h" 30 31 32struct BitBuffer ; 33 34class ALACEncoder 35{ 36 public : 37 ALACEncoder () ; 38 virtual ~ALACEncoder () ; 39 40 virtual int32_t Encode (AudioFormatDescription theInputFormat, AudioFormatDescription theOutputFormat, 41 unsigned char * theReadBuffer, unsigned char * theWriteBuffer, int32_t * ioNumBytes) ; 42 virtual int32_t Finish () ; 43 44 void SetFastMode (bool fast) { mFastMode = fast ; } ; 45 46 // this must be called *before* InitializeEncoder () 47 void SetFrameSize (uint32_t frameSize) { mFrameSize = frameSize ; } ; 48 49 void GetConfig (ALACSpecificConfig & config) ; 50 uint32_t GetMagicCookieSize (uint32_t inNumChannels) ; 51 void GetMagicCookie (void * config, uint32_t * ioSize) ; 52 53 virtual int32_t InitializeEncoder (AudioFormatDescription theOutputFormat) ; 54 55 protected : 56 virtual void GetSourceFormat (const AudioFormatDescription * source, AudioFormatDescription * output) ; 57 58 int32_t EncodeStereo (struct BitBuffer * bitstream, void * input, uint32_t stride, uint32_t channelIndex, uint32_t numSamples) ; 59 int32_t EncodeStereoFast (struct BitBuffer * bitstream, void * input, uint32_t stride, uint32_t channelIndex, uint32_t numSamples) ; 60 int32_t EncodeStereoEscape (struct BitBuffer * bitstream, void * input, uint32_t stride, uint32_t numSamples) ; 61 int32_t EncodeMono (struct BitBuffer * bitstream, void * input, uint32_t stride, uint32_t channelIndex, uint32_t numSamples) ; 62 63 64 // ALAC encoder parameters 65 int16_t mBitDepth ; 66 bool mFastMode ; 67 68 // encoding state 69 int16_t mLastMixRes [kALACMaxChannels] ; 70 71 // encoding buffers 72 int32_t * mMixBufferU ; 73 int32_t * mMixBufferV ; 74 int32_t * mPredictorU ; 75 int32_t * mPredictorV ; 76 uint16_t * mShiftBufferUV ; 77 78 uint8_t * mWorkBuffer ; 79 80 // per-channel coefficients buffers 81 int16_t mCoefsU [kALACMaxChannels][kALACMaxSearches][kALACMaxCoefs] ; 82 int16_t mCoefsV [kALACMaxChannels][kALACMaxSearches][kALACMaxCoefs] ; 83 84 // encoding statistics 85 uint32_t mTotalBytesGenerated ; 86 uint32_t mAvgBitRate ; 87 uint32_t mMaxFrameBytes ; 88 uint32_t mFrameSize ; 89 uint32_t mMaxOutputBytes ; 90 uint32_t mNumChannels ; 91 uint32_t mOutputSampleRate ; 92} ; 93