src/lib/alac/codec/ALACAudioTypes.h

   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:           ALACAudioTypes.h
  23 */
  24
  25 #ifndef ALACAUDIOTYPES_H
  26 #define ALACAUDIOTYPES_H
  27
  28 #if PRAGMA_ONCE
  29 #pragma once
  30 #endif
  31
  32 #ifdef __cplusplus
  33 extern "C" {
  34 #endif
  35
  36 #if PRAGMA_STRUCT_ALIGN
  37     #pragma options align=mac68k
  38 #elif PRAGMA_STRUCT_PACKPUSH
  39     #pragma pack(push, 2)
  40 #elif PRAGMA_STRUCT_PACK
  41     #pragma pack(2)
  42 #endif
  43
  44 #include <stdint.h>
  45
  46 #if defined(__ppc__)
  47 #define TARGET_RT_BIG_ENDIAN 1
  48 #elif defined(__ppc64__)
  49 #define TARGET_RT_BIG_ENDIAN 1
  50 #endif
  51
  52 #define kChannelAtomSize 12
  53
  54 enum
  55 {
  56     kALAC_UnimplementedError   = -4,
  57     kALAC_FileNotFoundError    = -43,
  58     kALAC_ParamError           = -50,
  59     kALAC_MemFullError         = -108
  60 };
  61
  62 enum
  63 {
  64     kALACFormatAppleLossless = 'alac',
  65     kALACFormatLinearPCM = 'lpcm'
  66 };
  67
  68 enum
  69 {
  70     kALACMaxChannels    = 8,
  71     kALACMaxEscapeHeaderBytes = 8,
  72     kALACMaxSearches    = 16,
  73     kALACMaxCoefs               = 16,
  74     kALACDefaultFramesPerPacket = 4096
  75 };
  76
  77 typedef uint32_t ALACChannelLayoutTag;
  78
  79 enum
  80 {
  81     kALACFormatFlagIsFloat                     = (1 << 0),     // 0x1
  82     kALACFormatFlagIsBigEndian                 = (1 << 1),     // 0x2
  83     kALACFormatFlagIsSignedInteger             = (1 << 2),     // 0x4
  84     kALACFormatFlagIsPacked                    = (1 << 3),     // 0x8
  85     kALACFormatFlagIsAlignedHigh               = (1 << 4),     // 0x10
  86 };
  87
  88 enum
  89 {
  90 #if TARGET_RT_BIG_ENDIAN
  91     kALACFormatFlagsNativeEndian       = kALACFormatFlagIsBigEndian
  92 #else
  93     kALACFormatFlagsNativeEndian       = 0
  94 #endif
  95 };
  96
  97 // this is required to be an IEEE 64bit float
  98 typedef double alac_float64_t;
  99
 100 // These are the Channel Layout Tags used in the Channel Layout Info portion of the ALAC magic cookie
 101 enum
 102 {
 103     kALACChannelLayoutTag_Mono          = (100<<16) | 1,    // C
 104     kALACChannelLayoutTag_Stereo        = (101<<16) | 2,        // L R
 105     kALACChannelLayoutTag_MPEG_3_0_B    = (113<<16) | 3,        // C L R
 106     kALACChannelLayoutTag_MPEG_4_0_B    = (116<<16) | 4,        // C L R Cs
 107     kALACChannelLayoutTag_MPEG_5_0_D    = (120<<16) | 5,    // C L R Ls Rs
 108     kALACChannelLayoutTag_MPEG_5_1_D    = (124<<16) | 6,        // C L R Ls Rs LFE
 109     kALACChannelLayoutTag_AAC_6_1       = (142<<16) | 7,        // C L R Ls Rs Cs LFE
 110     kALACChannelLayoutTag_MPEG_7_1_B    = (127<<16) | 8     // C Lc Rc L R Ls Rs LFE    (doc: IS-13818-7 MPEG2-AAC)
 111 };
 112
 113 // ALAC currently only utilizes these channels layouts. There is a one for one correspondance between a
 114 // given number of channels and one of these layout tags
 115 static const ALACChannelLayoutTag       ALACChannelLayoutTags[kALACMaxChannels] =
 116 {
 117     kALACChannelLayoutTag_Mono,         // C
 118     kALACChannelLayoutTag_Stereo,               // L R
 119     kALACChannelLayoutTag_MPEG_3_0_B,   // C L R
 120     kALACChannelLayoutTag_MPEG_4_0_B,   // C L R Cs
 121     kALACChannelLayoutTag_MPEG_5_0_D,   // C L R Ls Rs
 122     kALACChannelLayoutTag_MPEG_5_1_D,   // C L R Ls Rs LFE
 123     kALACChannelLayoutTag_AAC_6_1,              // C L R Ls Rs Cs LFE
 124     kALACChannelLayoutTag_MPEG_7_1_B    // C Lc Rc L R Ls Rs LFE    (doc: IS-13818-7 MPEG2-AAC)
 125 };
 126
 127 // AudioChannelLayout from CoreAudioTypes.h. We never need the AudioChannelDescription so we remove it
 128 struct ALACAudioChannelLayout
 129 {
 130     ALACChannelLayoutTag          mChannelLayoutTag;
 131     uint32_t                      mChannelBitmap;
 132     uint32_t                      mNumberChannelDescriptions;
 133 };
 134 typedef struct ALACAudioChannelLayout ALACAudioChannelLayout;
 135
 136 struct AudioFormatDescription
 137 {
 138     alac_float64_t mSampleRate;
 139     uint32_t  mFormatID;
 140     uint32_t  mFormatFlags;
 141     uint32_t  mBytesPerPacket;
 142     uint32_t  mFramesPerPacket;
 143     uint32_t  mBytesPerFrame;
 144     uint32_t  mChannelsPerFrame;
 145     uint32_t  mBitsPerChannel;
 146     uint32_t  mReserved;
 147 };
 148 typedef struct AudioFormatDescription  AudioFormatDescription;
 149
 150 /* Lossless Definitions */
 151
 152 enum
 153 {
 154         kALACCodecFormat                = 'alac',
 155         kALACVersion                    = 0,
 156         kALACCompatibleVersion  = kALACVersion,
 157         kALACDefaultFrameSize   = 4096
 158 };
 159
 160 // note: this struct is wrapped in an 'alac' atom in the sample description extension area
 161 // note: in QT movies, it will be further wrapped in a 'wave' atom surrounded by 'frma' and 'term' atoms
 162 typedef struct ALACSpecificConfig
 163 {
 164         uint32_t                                frameLength;
 165         uint8_t                                 compatibleVersion;
 166         uint8_t                                 bitDepth;                                                       // max 32
 167         uint8_t                                 pb;                                                                     // 0 <= pb <= 255
 168         uint8_t                                 mb;
 169         uint8_t                                 kb;
 170         uint8_t                                 numChannels;
 171         uint16_t                                maxRun;
 172         uint32_t                                maxFrameBytes;
 173         uint32_t                                avgBitRate;
 174         uint32_t                                sampleRate;
 175
 176 } ALACSpecificConfig;
 177
 178
 179 // The AudioChannelLayout atom type is not exposed yet so define it here
 180 enum
 181 {
 182         AudioChannelLayoutAID = 'chan'
 183 };
 184
 185 #if PRAGMA_STRUCT_ALIGN
 186     #pragma options align=reset
 187 #elif PRAGMA_STRUCT_PACKPUSH
 188     #pragma pack(pop)
 189 #elif PRAGMA_STRUCT_PACK
 190     #pragma pack()
 191 #endif
 192
 193 #ifdef __cplusplus
 194 }
 195 #endif
 196
 197 #endif  /* ALACAUDIOTYPES_H */