1 /* 2 * ALAC (Apple Lossless Audio Codec) decoder 3 * Copyright (c) 2005 David Hammerton 4 * All rights reserved. 5 * 6 * This is the actual decoder. 7 * 8 * http://crazney.net/programs/itunes/alac.html 9 * 10 * Permission is hereby granted, free of charge, to any person 11 * obtaining a copy of this software and associated documentation 12 * files (the "Software"), to deal in the Software without 13 * restriction, including without limitation the rights to use, 14 * copy, modify, merge, publish, distribute, sublicense, and/or 15 * sell copies of the Software, and to permit persons to whom the 16 * Software is furnished to do so, subject to the following conditions: 17 * 18 * The above copyright notice and this permission notice shall be 19 * included in all copies or substantial portions of the Software. 20 * 21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 22 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES 23 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 24 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 25 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 26 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 27 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 28 * OTHER DEALINGS IN THE SOFTWARE. 29 * 30 */ 31 32 #ifndef __ALAC__DECOMP_H 33 #define __ALAC__DECOMP_H 34 35 #include <stdint.h> 36 37 #ifdef __cplusplus 38 extern "C" { 39 #endif 40 41 42 typedef struct alac_file alac_file; 43 44 alac_file *create_alac(int samplesize, int numchannels); 45 void dispose_alac(alac_file* alac); 46 void decode_frame(alac_file *alac, 47 unsigned char *inbuffer, 48 void *outbuffer, int *outputsize); 49 void alac_set_info(alac_file *alac, char *inputbuffer); 50 51 struct alac_file 52 { 53 unsigned char *input_buffer; 54 int input_buffer_bitaccumulator; /* used so we can do arbitary 55 bit reads */ 56 57 int samplesize; 58 int numchannels; 59 int bytespersample; 60 61 /* buffers */ 62 int32_t *predicterror_buffer_a; 63 int32_t *predicterror_buffer_b; 64 65 int32_t *outputsamples_buffer_a; 66 int32_t *outputsamples_buffer_b; 67 68 int32_t *uncompressed_bytes_buffer_a; 69 int32_t *uncompressed_bytes_buffer_b; 70 71 /* stuff from setinfo */ 72 uint32_t setinfo_max_samples_per_frame; /* 0x1000 = 4096 */ /* max samples per frame? */ 73 uint8_t setinfo_7a; /* 0x00 */ 74 uint8_t setinfo_sample_size; /* 0x10 */ 75 uint8_t setinfo_rice_historymult; /* 0x28 */ 76 uint8_t setinfo_rice_initialhistory; /* 0x0a */ 77 uint8_t setinfo_rice_kmodifier; /* 0x0e */ 78 uint8_t setinfo_7f; /* 0x02 */ 79 uint16_t setinfo_80; /* 0x00ff */ 80 uint32_t setinfo_82; /* 0x000020e7 */ /* max sample size?? */ 81 uint32_t setinfo_86; /* 0x00069fe4 */ /* bit rate (avarge)?? */ 82 uint32_t setinfo_8a_rate; /* 0x0000ac44 */ 83 /* end setinfo stuff */ 84 85 }; 86 87 #ifdef __cplusplus 88 } 89 #endif 90 91 #endif /* __ALAC__DECOMP_H */ 92 93