| 1 | /* |
| 2 | * This file is part of DisOrder |
| 3 | * Copyright (C) 2007 Richard Kettlewell |
| 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, but |
| 11 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | * 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 |
| 18 | * USA |
| 19 | */ |
| 20 | /** @file server/decode.c |
| 21 | * @brief General-purpose decoder for use by speaker process |
| 22 | */ |
| 23 | |
| 24 | #include <config.h> |
| 25 | #include "types.h" |
| 26 | |
| 27 | #include <getopt.h> |
| 28 | #include <unistd.h> |
| 29 | #include <fcntl.h> |
| 30 | #include <errno.h> |
| 31 | #include <stdlib.h> |
| 32 | #include <locale.h> |
| 33 | #include <assert.h> |
| 34 | #include <fnmatch.h> |
| 35 | #include <mad.h> |
| 36 | #include <vorbis/vorbisfile.h> |
| 37 | |
| 38 | #include "log.h" |
| 39 | #include "syscalls.h" |
| 40 | #include "defs.h" |
| 41 | #include "speaker-protocol.h" |
| 42 | |
| 43 | /** @brief Encoding lookup table type */ |
| 44 | struct decoder { |
| 45 | /** @brief Glob pattern matching file */ |
| 46 | const char *pattern; |
| 47 | /** @brief Decoder function */ |
| 48 | void (*decode)(void); |
| 49 | }; |
| 50 | |
| 51 | /** @brief Input file */ |
| 52 | static int inputfd; |
| 53 | |
| 54 | /** @brief Output file */ |
| 55 | static FILE *outputfp; |
| 56 | |
| 57 | /** @brief Filename */ |
| 58 | static const char *path; |
| 59 | |
| 60 | /** @brief Input buffer */ |
| 61 | static char buffer[1048576]; |
| 62 | |
| 63 | /** @brief Open the input file */ |
| 64 | static void open_input(void) { |
| 65 | if((inputfd = open(path, O_RDONLY)) < 0) |
| 66 | fatal(errno, "opening %s", path); |
| 67 | } |
| 68 | |
| 69 | /** @brief Fill the buffer |
| 70 | * @return Number of bytes read |
| 71 | */ |
| 72 | static size_t fill(void) { |
| 73 | int n = read(inputfd, buffer, sizeof buffer); |
| 74 | |
| 75 | if(n < 0) |
| 76 | fatal(errno, "reading from %s", path); |
| 77 | return n; |
| 78 | } |
| 79 | |
| 80 | /** @brief Write a 16-bit word in bigendian format */ |
| 81 | static inline void output_16(uint16_t n) { |
| 82 | if(putc(n >> 8, outputfp) < 0 |
| 83 | || putc(n & 0xFF, outputfp) < 0) |
| 84 | fatal(errno, "decoding %s: output error", path); |
| 85 | } |
| 86 | |
| 87 | /** @brief Write the header |
| 88 | * If called more than once, either does nothing (if you kept the same |
| 89 | * output encoding) or fails (if you changed it). |
| 90 | */ |
| 91 | static void output_header(int rate, |
| 92 | int channels, |
| 93 | int bits, |
| 94 | int nbytes) { |
| 95 | struct stream_header header; |
| 96 | |
| 97 | header.rate = rate; |
| 98 | header.bits = bits; |
| 99 | header.channels = channels; |
| 100 | header.endian = ENDIAN_BIG; |
| 101 | header.nbytes = nbytes; |
| 102 | if(fwrite(&header, sizeof header, 1, outputfp) < 1) |
| 103 | fatal(errno, "decoding %s: writing format header", path); |
| 104 | } |
| 105 | |
| 106 | /** @brief Dithering state |
| 107 | * Filched from mpg321, which credits it to Robert Leslie */ |
| 108 | struct audio_dither { |
| 109 | mad_fixed_t error[3]; |
| 110 | mad_fixed_t random; |
| 111 | }; |
| 112 | |
| 113 | /** @brief 32-bit PRNG |
| 114 | * Filched from mpg321, which credits it to Robert Leslie */ |
| 115 | static inline unsigned long prng(unsigned long state) |
| 116 | { |
| 117 | return (state * 0x0019660dL + 0x3c6ef35fL) & 0xffffffffL; |
| 118 | } |
| 119 | |
| 120 | /** @brief Generic linear sample quantize and dither routine |
| 121 | * Filched from mpg321, which credits it to Robert Leslie */ |
| 122 | #define bits 16 |
| 123 | static long audio_linear_dither(mad_fixed_t sample, |
| 124 | struct audio_dither *dither) { |
| 125 | unsigned int scalebits; |
| 126 | mad_fixed_t output, mask, rnd; |
| 127 | |
| 128 | enum { |
| 129 | MIN = -MAD_F_ONE, |
| 130 | MAX = MAD_F_ONE - 1 |
| 131 | }; |
| 132 | |
| 133 | /* noise shape */ |
| 134 | sample += dither->error[0] - dither->error[1] + dither->error[2]; |
| 135 | |
| 136 | dither->error[2] = dither->error[1]; |
| 137 | dither->error[1] = dither->error[0] / 2; |
| 138 | |
| 139 | /* bias */ |
| 140 | output = sample + (1L << (MAD_F_FRACBITS + 1 - bits - 1)); |
| 141 | |
| 142 | scalebits = MAD_F_FRACBITS + 1 - bits; |
| 143 | mask = (1L << scalebits) - 1; |
| 144 | |
| 145 | /* dither */ |
| 146 | rnd = prng(dither->random); |
| 147 | output += (rnd & mask) - (dither->random & mask); |
| 148 | |
| 149 | dither->random = rnd; |
| 150 | |
| 151 | /* clip */ |
| 152 | if (output > MAX) { |
| 153 | output = MAX; |
| 154 | |
| 155 | if (sample > MAX) |
| 156 | sample = MAX; |
| 157 | } |
| 158 | else if (output < MIN) { |
| 159 | output = MIN; |
| 160 | |
| 161 | if (sample < MIN) |
| 162 | sample = MIN; |
| 163 | } |
| 164 | |
| 165 | /* quantize */ |
| 166 | output &= ~mask; |
| 167 | |
| 168 | /* error feedback */ |
| 169 | dither->error[0] = sample - output; |
| 170 | |
| 171 | /* scale */ |
| 172 | return output >> scalebits; |
| 173 | } |
| 174 | #undef bits |
| 175 | |
| 176 | /** @brief MP3 output callback */ |
| 177 | static enum mad_flow mp3_output(void attribute((unused)) *data, |
| 178 | struct mad_header const *header, |
| 179 | struct mad_pcm *pcm) { |
| 180 | size_t n = pcm->length; |
| 181 | const mad_fixed_t *l = pcm->samples[0], *r = pcm->samples[1]; |
| 182 | static struct audio_dither ld[1], rd[1]; |
| 183 | |
| 184 | output_header(header->samplerate, |
| 185 | pcm->channels, |
| 186 | 16, |
| 187 | 2 * pcm->channels * pcm->length); |
| 188 | switch(pcm->channels) { |
| 189 | case 1: |
| 190 | while(n--) |
| 191 | output_16(audio_linear_dither(*l++, ld)); |
| 192 | break; |
| 193 | case 2: |
| 194 | while(n--) { |
| 195 | output_16(audio_linear_dither(*l++, ld)); |
| 196 | output_16(audio_linear_dither(*r++, rd)); |
| 197 | } |
| 198 | break; |
| 199 | default: |
| 200 | fatal(0, "decoding %s: unsupported channel count %d", path, pcm->channels); |
| 201 | } |
| 202 | return MAD_FLOW_CONTINUE; |
| 203 | } |
| 204 | |
| 205 | /** @brief MP3 input callback */ |
| 206 | static enum mad_flow mp3_input(void attribute((unused)) *data, |
| 207 | struct mad_stream *stream) { |
| 208 | const size_t n = fill(); |
| 209 | |
| 210 | if(!n) |
| 211 | return MAD_FLOW_STOP; |
| 212 | mad_stream_buffer(stream, (unsigned char *)buffer, n); |
| 213 | return MAD_FLOW_CONTINUE; |
| 214 | } |
| 215 | |
| 216 | |
| 217 | /** @brief MP3 error callback */ |
| 218 | static enum mad_flow mp3_error(void attribute((unused)) *data, |
| 219 | struct mad_stream *stream, |
| 220 | struct mad_frame attribute((unused)) *frame) { |
| 221 | if(0) |
| 222 | /* Just generates pointless verbosity l-( */ |
| 223 | error(0, "decoding %s: %s (%#04x)", |
| 224 | path, mad_stream_errorstr(stream), stream->error); |
| 225 | return MAD_FLOW_CONTINUE; |
| 226 | } |
| 227 | |
| 228 | /** @brief MP3 decoder */ |
| 229 | static void decode_mp3(void) { |
| 230 | struct mad_decoder mad[1]; |
| 231 | |
| 232 | open_input(); |
| 233 | mad_decoder_init(mad, 0/*data*/, mp3_input, 0/*header*/, 0/*filter*/, |
| 234 | mp3_output, mp3_error, 0/*message*/); |
| 235 | if(mad_decoder_run(mad, MAD_DECODER_MODE_SYNC)) |
| 236 | exit(1); |
| 237 | mad_decoder_finish(mad); |
| 238 | } |
| 239 | |
| 240 | /** @brief OGG decoder */ |
| 241 | static void decode_ogg(void) { |
| 242 | FILE *fp; |
| 243 | OggVorbis_File vf[1]; |
| 244 | int err; |
| 245 | long n; |
| 246 | int bitstream; |
| 247 | vorbis_info *vi; |
| 248 | |
| 249 | if(!(fp = fopen(path, "rb"))) |
| 250 | fatal(errno, "cannot open %s", path); |
| 251 | /* There doesn't seem to be any standard function for mapping the error codes |
| 252 | * to strings l-( */ |
| 253 | if((err = ov_open(fp, vf, 0/*initial*/, 0/*ibytes*/))) |
| 254 | fatal(0, "ov_fopen %s: %d", path, err); |
| 255 | if(!(vi = ov_info(vf, 0/*link*/))) |
| 256 | fatal(0, "ov_info %s: failed", path); |
| 257 | while((n = ov_read(vf, buffer, sizeof buffer, 1/*bigendianp*/, |
| 258 | 2/*bytes/word*/, 1/*signed*/, &bitstream))) { |
| 259 | if(n < 0) |
| 260 | fatal(0, "ov_read %s: %ld", path, n); |
| 261 | if(bitstream > 0) |
| 262 | fatal(0, "only single-bitstream ogg files are supported"); |
| 263 | output_header(vi->rate, vi->channels, 16/*bits*/, n); |
| 264 | if(fwrite(buffer, 1, n, outputfp) < (size_t)n) |
| 265 | fatal(errno, "decoding %s: writing sample data", path); |
| 266 | } |
| 267 | } |
| 268 | |
| 269 | /** @brief Lookup table of decoders */ |
| 270 | static const struct decoder decoders[] = { |
| 271 | { "*.mp3", decode_mp3 }, |
| 272 | { "*.MP3", decode_mp3 }, |
| 273 | { "*.ogg", decode_ogg }, |
| 274 | { "*.OGG", decode_ogg }, |
| 275 | { 0, 0 } |
| 276 | }; |
| 277 | |
| 278 | static const struct option options[] = { |
| 279 | { "help", no_argument, 0, 'h' }, |
| 280 | { "version", no_argument, 0, 'V' }, |
| 281 | { 0, 0, 0, 0 } |
| 282 | }; |
| 283 | |
| 284 | /* Display usage message and terminate. */ |
| 285 | static void help(void) { |
| 286 | xprintf("Usage:\n" |
| 287 | " disorder-decode [OPTIONS] PATH\n" |
| 288 | "Options:\n" |
| 289 | " --help, -h Display usage message\n" |
| 290 | " --version, -V Display version number\n" |
| 291 | "\n" |
| 292 | "Audio decoder for DisOrder. Only intended to be used by speaker\n" |
| 293 | "process, not for normal users.\n"); |
| 294 | xfclose(stdout); |
| 295 | exit(0); |
| 296 | } |
| 297 | |
| 298 | /* Display version number and terminate. */ |
| 299 | static void version(void) { |
| 300 | xprintf("disorder-decode version %s\n", disorder_version_string); |
| 301 | xfclose(stdout); |
| 302 | exit(0); |
| 303 | } |
| 304 | |
| 305 | int main(int argc, char **argv) { |
| 306 | int n; |
| 307 | const char *e; |
| 308 | |
| 309 | set_progname(argv); |
| 310 | if(!setlocale(LC_CTYPE, "")) fatal(errno, "calling setlocale"); |
| 311 | while((n = getopt_long(argc, argv, "hV", options, 0)) >= 0) { |
| 312 | switch(n) { |
| 313 | case 'h': help(); |
| 314 | case 'V': version(); |
| 315 | default: fatal(0, "invalid option"); |
| 316 | } |
| 317 | } |
| 318 | if(optind >= argc) |
| 319 | fatal(0, "missing filename"); |
| 320 | if(optind + 1 < argc) |
| 321 | fatal(0, "excess arguments"); |
| 322 | if((e = getenv("DISORDER_RAW_FD"))) { |
| 323 | if(!(outputfp = fdopen(atoi(e), "wb"))) |
| 324 | fatal(errno, "fdopen"); |
| 325 | } else |
| 326 | outputfp = stdout; |
| 327 | path = argv[optind]; |
| 328 | for(n = 0; |
| 329 | decoders[n].pattern |
| 330 | && fnmatch(decoders[n].pattern, path, 0) != 0; |
| 331 | ++n) |
| 332 | ; |
| 333 | if(!decoders[n].pattern) |
| 334 | fatal(0, "cannot determine file type for %s", path); |
| 335 | decoders[n].decode(); |
| 336 | xfclose(outputfp); |
| 337 | return 0; |
| 338 | } |
| 339 | |
| 340 | /* |
| 341 | Local Variables: |
| 342 | c-basic-offset:2 |
| 343 | comment-column:40 |
| 344 | fill-column:79 |
| 345 | indent-tabs-mode:nil |
| 346 | End: |
| 347 | */ |