Alexandre Lision | 8af73cb | 2013-12-10 14:11:20 -0500 | [diff] [blame] | 1 | /* $Id$ */ |
| 2 | /* |
| 3 | * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com) |
| 4 | * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | */ |
| 20 | #ifndef __PJMEDIA_WAVE_H__ |
| 21 | #define __PJMEDIA_WAVE_H__ |
| 22 | |
| 23 | |
| 24 | /** |
| 25 | * @file wave.h |
| 26 | * @brief WAVE file manipulation. |
| 27 | */ |
| 28 | #include <pjmedia/types.h> |
| 29 | |
| 30 | /** |
| 31 | * @defgroup PJMEDIA_FILE_FORMAT File Formats |
| 32 | * @brief Supported file formats |
| 33 | */ |
| 34 | |
| 35 | |
| 36 | /** |
| 37 | * @defgroup PJMEDIA_WAVE WAVE Header |
| 38 | * @ingroup PJMEDIA_FILE_FORMAT |
| 39 | * @brief Representation of RIFF/WAVE file format |
| 40 | * @{ |
| 41 | * |
| 42 | * This the the low level representation of RIFF/WAVE file format. For |
| 43 | * higher abstraction, please see \ref PJMEDIA_FILE_PLAY and |
| 44 | * \ref PJMEDIA_FILE_REC. |
| 45 | */ |
| 46 | |
| 47 | |
| 48 | PJ_BEGIN_DECL |
| 49 | |
| 50 | /** |
| 51 | * Standard RIFF tag to identify RIFF file format in the WAVE header. |
| 52 | */ |
| 53 | #define PJMEDIA_RIFF_TAG ('F'<<24|'F'<<16|'I'<<8|'R') |
| 54 | |
| 55 | /** |
| 56 | * Standard WAVE tag to identify WAVE header. |
| 57 | */ |
| 58 | #define PJMEDIA_WAVE_TAG ('E'<<24|'V'<<16|'A'<<8|'W') |
| 59 | |
| 60 | /** |
| 61 | * Standard FMT tag to identify format chunks. |
| 62 | */ |
| 63 | #define PJMEDIA_FMT_TAG (' '<<24|'t'<<16|'m'<<8|'f') |
| 64 | |
| 65 | /** |
| 66 | * Standard DATA tag to identify data chunks. |
| 67 | */ |
| 68 | #define PJMEDIA_DATA_TAG ('a'<<24|'t'<<16|'a'<<8|'d') |
| 69 | |
| 70 | /** |
| 71 | * Standard FACT tag to identify fact chunks. |
| 72 | */ |
| 73 | #define PJMEDIA_FACT_TAG ('t'<<24|'c'<<16|'a'<<8|'f') |
| 74 | |
| 75 | |
| 76 | /** |
| 77 | * Enumeration of format compression tag. |
| 78 | */ |
| 79 | typedef enum { |
| 80 | PJMEDIA_WAVE_FMT_TAG_PCM = 1, |
| 81 | PJMEDIA_WAVE_FMT_TAG_ALAW = 6, |
| 82 | PJMEDIA_WAVE_FMT_TAG_ULAW = 7 |
| 83 | } pjmedia_wave_fmt_tag; |
| 84 | |
| 85 | |
| 86 | /** |
| 87 | * This file describes the simpler/canonical version of a WAVE file. |
| 88 | * It does not support the full RIFF format specification. |
| 89 | */ |
| 90 | #pragma pack(2) |
| 91 | struct pjmedia_wave_hdr |
| 92 | { |
| 93 | /** This structure describes RIFF WAVE file header */ |
| 94 | struct { |
| 95 | pj_uint32_t riff; /**< "RIFF" ASCII tag. */ |
| 96 | pj_uint32_t file_len; /**< File length minus 8 bytes */ |
| 97 | pj_uint32_t wave; /**< "WAVE" ASCII tag. */ |
| 98 | } riff_hdr; |
| 99 | |
| 100 | /** This structure describes format chunks/header */ |
| 101 | struct { |
| 102 | pj_uint32_t fmt; /**< "fmt " ASCII tag. */ |
| 103 | pj_uint32_t len; /**< 16 for PCM. */ |
| 104 | pj_uint16_t fmt_tag; /**< 1 for PCM */ |
| 105 | pj_uint16_t nchan; /**< Number of channels. */ |
| 106 | pj_uint32_t sample_rate; /**< Sampling rate. */ |
| 107 | pj_uint32_t bytes_per_sec; /**< Average bytes per second. */ |
| 108 | pj_uint16_t block_align; /**< nchannels * bits / 8 */ |
| 109 | pj_uint16_t bits_per_sample; /**< Bits per sample. */ |
| 110 | } fmt_hdr; |
| 111 | |
| 112 | /** The data header preceeds the actual data in the file. */ |
| 113 | struct { |
| 114 | pj_uint32_t data; /**< "data" ASCII tag. */ |
| 115 | pj_uint32_t len; /**< Data length. */ |
| 116 | } data_hdr; |
| 117 | }; |
| 118 | #pragma pack() |
| 119 | |
| 120 | /** |
| 121 | * @see pjmedia_wave_hdr |
| 122 | */ |
| 123 | typedef struct pjmedia_wave_hdr pjmedia_wave_hdr; |
| 124 | |
| 125 | /** |
| 126 | * This structure describes generic RIFF subchunk header. |
| 127 | */ |
| 128 | typedef struct pjmedia_wave_subchunk |
| 129 | { |
| 130 | pj_uint32_t id; /**< Subchunk ASCII tag. */ |
| 131 | pj_uint32_t len; /**< Length following this field */ |
| 132 | } pjmedia_wave_subchunk; |
| 133 | |
| 134 | |
| 135 | /** |
| 136 | * Normalize subchunk header from little endian (the representation of |
| 137 | * RIFF file) into host's endian. |
| 138 | */ |
| 139 | #if defined(PJ_IS_BIG_ENDIAN) && PJ_IS_BIG_ENDIAN!=0 |
| 140 | # define PJMEDIA_WAVE_NORMALIZE_SUBCHUNK(ch) \ |
| 141 | do { \ |
| 142 | (ch)->id = pj_swap32((ch)->id); \ |
| 143 | (ch)->len = pj_swap32((ch)->len); \ |
| 144 | } while (0) |
| 145 | #else |
| 146 | # define PJMEDIA_WAVE_NORMALIZE_SUBCHUNK(ch) |
| 147 | #endif |
| 148 | |
| 149 | |
| 150 | /** |
| 151 | * On big-endian hosts, this function swaps the byte order of the values |
| 152 | * in the WAVE header fields. On little-endian hosts, this function does |
| 153 | * nothing. |
| 154 | * |
| 155 | * Application SHOULD call this function after reading the WAVE header |
| 156 | * chunks from a file. |
| 157 | * |
| 158 | * @param hdr The WAVE header. |
| 159 | */ |
| 160 | PJ_DECL(void) pjmedia_wave_hdr_file_to_host( pjmedia_wave_hdr *hdr ); |
| 161 | |
| 162 | |
| 163 | /** |
| 164 | * On big-endian hosts, this function swaps the byte order of the values |
| 165 | * in the WAVE header fields. On little-endian hosts, this function does |
| 166 | * nothing. |
| 167 | * |
| 168 | * Application SHOULD call this function before writing the WAVE header |
| 169 | * to a file. |
| 170 | * |
| 171 | * @param hdr The WAVE header. |
| 172 | */ |
| 173 | PJ_DECL(void) pjmedia_wave_hdr_host_to_file( pjmedia_wave_hdr *hdr ); |
| 174 | |
| 175 | |
| 176 | PJ_END_DECL |
| 177 | |
| 178 | /** |
| 179 | * @} |
| 180 | */ |
| 181 | |
| 182 | |
| 183 | #endif /* __PJMEDIA_WAVE_H__ */ |
| 184 | |