blob: da6744d73dce3c5d78e07d4b01dad6e626c60ac6
| 1 | /* |
| 2 | * libmad - MPEG audio decoder library |
| 3 | * Copyright (C) 2000-2004 Underbit Technologies, Inc. |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License as published by |
| 7 | * the Free Software Foundation; either version 2 of the License, or |
| 8 | * (at your option) any later version. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program; if not, write to the Free Software |
| 17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 18 | * |
| 19 | * $Id: stream.h,v 1.20 2004/02/05 09:02:39 rob Exp $ |
| 20 | */ |
| 21 | |
| 22 | # ifndef LIBMAD_STREAM_H |
| 23 | # define LIBMAD_STREAM_H |
| 24 | |
| 25 | # include "bit.h" |
| 26 | |
| 27 | # define MAD_BUFFER_GUARD 8 |
| 28 | # define MAD_BUFFER_MDLEN (511 + 2048 + MAD_BUFFER_GUARD) |
| 29 | |
| 30 | enum mad_error { |
| 31 | MAD_ERROR_NONE = 0x0000, /* no error */ |
| 32 | |
| 33 | MAD_ERROR_BUFLEN = 0x0001, /* input buffer too small (or EOF) */ |
| 34 | MAD_ERROR_BUFPTR = 0x0002, /* invalid (null) buffer pointer */ |
| 35 | |
| 36 | MAD_ERROR_NOMEM = 0x0031, /* not enough memory */ |
| 37 | |
| 38 | MAD_ERROR_LOSTSYNC = 0x0101, /* lost synchronization */ |
| 39 | MAD_ERROR_BADLAYER = 0x0102, /* reserved header layer value */ |
| 40 | MAD_ERROR_BADBITRATE = 0x0103, /* forbidden bitrate value */ |
| 41 | MAD_ERROR_BADSAMPLERATE = 0x0104, /* reserved sample frequency value */ |
| 42 | MAD_ERROR_BADEMPHASIS = 0x0105, /* reserved emphasis value */ |
| 43 | |
| 44 | MAD_ERROR_BADCRC = 0x0201, /* CRC check failed */ |
| 45 | MAD_ERROR_BADBITALLOC = 0x0211, /* forbidden bit allocation value */ |
| 46 | MAD_ERROR_BADSCALEFACTOR = 0x0221, /* bad scalefactor index */ |
| 47 | MAD_ERROR_BADMODE = 0x0222, /* bad bitrate/mode combination */ |
| 48 | MAD_ERROR_BADFRAMELEN = 0x0231, /* bad frame length */ |
| 49 | MAD_ERROR_BADBIGVALUES = 0x0232, /* bad big_values count */ |
| 50 | MAD_ERROR_BADBLOCKTYPE = 0x0233, /* reserved block_type */ |
| 51 | MAD_ERROR_BADSCFSI = 0x0234, /* bad scalefactor selection info */ |
| 52 | MAD_ERROR_BADDATAPTR = 0x0235, /* bad main_data_begin pointer */ |
| 53 | MAD_ERROR_BADPART3LEN = 0x0236, /* bad audio data length */ |
| 54 | MAD_ERROR_BADHUFFTABLE = 0x0237, /* bad Huffman table select */ |
| 55 | MAD_ERROR_BADHUFFDATA = 0x0238, /* Huffman data overrun */ |
| 56 | MAD_ERROR_BADSTEREO = 0x0239 /* incompatible block_type for JS */ |
| 57 | }; |
| 58 | |
| 59 | # define MAD_RECOVERABLE(error) ((error) & 0xff00) |
| 60 | |
| 61 | struct mad_stream { |
| 62 | unsigned char const *buffer; /* input bitstream buffer */ |
| 63 | unsigned char const *bufend; /* end of buffer */ |
| 64 | unsigned long skiplen; /* bytes to skip before next frame */ |
| 65 | |
| 66 | int sync; /* stream sync found */ |
| 67 | unsigned long freerate; /* free bitrate (fixed) */ |
| 68 | |
| 69 | unsigned char const *this_frame; /* start of current frame */ |
| 70 | unsigned char const *next_frame; /* start of next frame */ |
| 71 | struct mad_bitptr ptr; /* current processing bit pointer */ |
| 72 | |
| 73 | struct mad_bitptr anc_ptr; /* ancillary bits pointer */ |
| 74 | unsigned int anc_bitlen; /* number of ancillary bits */ |
| 75 | |
| 76 | unsigned char(*main_data)[MAD_BUFFER_MDLEN]; |
| 77 | /* Layer III main_data() */ |
| 78 | unsigned int md_len; /* bytes in main_data */ |
| 79 | |
| 80 | int options; /* decoding options (see below) */ |
| 81 | enum mad_error error; /* error code (see above) */ |
| 82 | |
| 83 | unsigned int muted_samples; |
| 84 | unsigned int muted_count; |
| 85 | }; |
| 86 | |
| 87 | enum { |
| 88 | MAD_OPTION_IGNORECRC = 0x0001, /* ignore CRC errors */ |
| 89 | MAD_OPTION_HALFSAMPLERATE = 0x0002 /* generate PCM at 1/2 sample rate */ |
| 90 | # if 0 /* not yet implemented */ |
| 91 | MAD_OPTION_LEFTCHANNEL = 0x0010, /* decode left channel only */ |
| 92 | MAD_OPTION_RIGHTCHANNEL = 0x0020, /* decode right channel only */ |
| 93 | MAD_OPTION_SINGLECHANNEL = 0x0030 /* combine channels */ |
| 94 | # endif |
| 95 | }; |
| 96 | |
| 97 | void mad_stream_init(struct mad_stream *); |
| 98 | void mad_stream_finish(struct mad_stream *); |
| 99 | |
| 100 | # define mad_stream_options(stream, opts) \ |
| 101 | ((void) ((stream)->options = (opts))) |
| 102 | |
| 103 | void mad_stream_buffer(struct mad_stream *, |
| 104 | unsigned char const *, unsigned long); |
| 105 | void mad_stream_skip(struct mad_stream *, unsigned long); |
| 106 | |
| 107 | int mad_stream_sync(struct mad_stream *); |
| 108 | |
| 109 | char const *mad_stream_errorstr(struct mad_stream const *); |
| 110 | |
| 111 | # endif |
| 112 |