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/*
* 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: ALACAudioTypes.h
*/
#ifndef ALACAUDIOTYPES_H
#define ALACAUDIOTYPES_H
#if PRAGMA_ONCE
#pragma once
#endif
#include "config.h"
#ifdef __cplusplus
extern "C" {
#endif
#if PRAGMA_STRUCT_ALIGN
#pragma options align=mac68k
#elif PRAGMA_STRUCT_PACKPUSH
#pragma pack(push, 2)
#elif PRAGMA_STRUCT_PACK
#pragma pack(2)
#endif
#include <stdint.h>
#ifdef WORDS_BIGENDIAN
#define TARGET_RT_BIG_ENDIAN 1
#endif
#define kChannelAtomSize 12
enum
{
kALAC_UnimplementedError = -4,
kALAC_FileNotFoundError = -43,
kALAC_ParamError = -50,
kALAC_MemFullError = -108
};
enum
{
kALACFormatAppleLossless = 'alac',
kALACFormatLinearPCM = 'lpcm'
};
enum
{
kALACMaxChannels = 8,
kALACMaxEscapeHeaderBytes = 8,
kALACMaxSearches = 16,
kALACMaxCoefs = 16,
kALACDefaultFramesPerPacket = 4096
};
typedef uint32_t ALACChannelLayoutTag;
enum
{
kALACFormatFlagIsFloat = (1 << 0), // 0x1
kALACFormatFlagIsBigEndian = (1 << 1), // 0x2
kALACFormatFlagIsSignedInteger = (1 << 2), // 0x4
kALACFormatFlagIsPacked = (1 << 3), // 0x8
kALACFormatFlagIsAlignedHigh = (1 << 4), // 0x10
};
enum
{
#if TARGET_RT_BIG_ENDIAN
kALACFormatFlagsNativeEndian = kALACFormatFlagIsBigEndian
#else
kALACFormatFlagsNativeEndian = 0
#endif
};
// this is required to be an IEEE 64bit float
typedef double alac_float64_t;
// These are the Channel Layout Tags used in the Channel Layout Info portion of the ALAC magic cookie
enum
{
kALACChannelLayoutTag_Mono = (100<<16) | 1, // C
kALACChannelLayoutTag_Stereo = (101<<16) | 2, // L R
kALACChannelLayoutTag_MPEG_3_0_B = (113<<16) | 3, // C L R
kALACChannelLayoutTag_MPEG_4_0_B = (116<<16) | 4, // C L R Cs
kALACChannelLayoutTag_MPEG_5_0_D = (120<<16) | 5, // C L R Ls Rs
kALACChannelLayoutTag_MPEG_5_1_D = (124<<16) | 6, // C L R Ls Rs LFE
kALACChannelLayoutTag_AAC_6_1 = (142<<16) | 7, // C L R Ls Rs Cs LFE
kALACChannelLayoutTag_MPEG_7_1_B = (127<<16) | 8 // C Lc Rc L R Ls Rs LFE (doc: IS-13818-7 MPEG2-AAC)
};
// ALAC currently only utilizes these channels layouts. There is a one for one correspondance between a
// given number of channels and one of these layout tags
static const ALACChannelLayoutTag ALACChannelLayoutTags[kALACMaxChannels] =
{
kALACChannelLayoutTag_Mono, // C
kALACChannelLayoutTag_Stereo, // L R
kALACChannelLayoutTag_MPEG_3_0_B, // C L R
kALACChannelLayoutTag_MPEG_4_0_B, // C L R Cs
kALACChannelLayoutTag_MPEG_5_0_D, // C L R Ls Rs
kALACChannelLayoutTag_MPEG_5_1_D, // C L R Ls Rs LFE
kALACChannelLayoutTag_AAC_6_1, // C L R Ls Rs Cs LFE
kALACChannelLayoutTag_MPEG_7_1_B // C Lc Rc L R Ls Rs LFE (doc: IS-13818-7 MPEG2-AAC)
};
// AudioChannelLayout from CoreAudioTypes.h. We never need the AudioChannelDescription so we remove it
struct ALACAudioChannelLayout
{
ALACChannelLayoutTag mChannelLayoutTag;
uint32_t mChannelBitmap;
uint32_t mNumberChannelDescriptions;
};
typedef struct ALACAudioChannelLayout ALACAudioChannelLayout;
struct AudioFormatDescription
{
alac_float64_t mSampleRate;
uint32_t mFormatID;
uint32_t mFormatFlags;
uint32_t mBytesPerPacket;
uint32_t mFramesPerPacket;
uint32_t mBytesPerFrame;
uint32_t mChannelsPerFrame;
uint32_t mBitsPerChannel;
uint32_t mReserved;
};
typedef struct AudioFormatDescription AudioFormatDescription;
/* Lossless Definitions */
enum
{
kALACCodecFormat = 'alac',
kALACVersion = 0,
kALACCompatibleVersion = kALACVersion,
kALACDefaultFrameSize = 4096
};
// note: this struct is wrapped in an 'alac' atom in the sample description extension area
// note: in QT movies, it will be further wrapped in a 'wave' atom surrounded by 'frma' and 'term' atoms
typedef struct ALACSpecificConfig
{
uint32_t frameLength;
uint8_t compatibleVersion;
uint8_t bitDepth; // max 32
uint8_t pb; // 0 <= pb <= 255
uint8_t mb;
uint8_t kb;
uint8_t numChannels;
uint16_t maxRun;
uint32_t maxFrameBytes;
uint32_t avgBitRate;
uint32_t sampleRate;
} ALACSpecificConfig;
// The AudioChannelLayout atom type is not exposed yet so define it here
enum
{
AudioChannelLayoutAID = 'chan'
};
#if PRAGMA_STRUCT_ALIGN
#pragma options align=reset
#elif PRAGMA_STRUCT_PACKPUSH
#pragma pack(pop)
#elif PRAGMA_STRUCT_PACK
#pragma pack()
#endif
#ifdef __cplusplus
}
#endif
#endif /* ALACAUDIOTYPES_H */
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