mdw@git.distorted.org.uk Git - disorder/blob - server/decode.c

   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 #include <FLAC/file_decoder.h>
  38
  39 #include "log.h"
  40 #include "syscalls.h"
  41 #include "defs.h"
  42 #include "wav.h"
  43 #include "speaker-protocol.h"
  44
  45 /** @brief Encoding lookup table type */
  46 struct decoder {
  47   /** @brief Glob pattern matching file */
  48   const char *pattern;
  49   /** @brief Decoder function */
  50   void (*decode)(void);
  51 };
  52
  53 /** @brief Input file */
  54 static int inputfd;
  55
  56 /** @brief Output file */
  57 static FILE *outputfp;
  58
  59 /** @brief Filename */
  60 static const char *path;
  61
  62 /** @brief Input buffer */
  63 static char input_buffer[1048576];
  64
  65 /** @brief Open the input file */
  66 static void open_input(void) {
  67   if((inputfd = open(path, O_RDONLY)) < 0)
  68     fatal(errno, "opening %s", path);
  69 }
  70
  71 /** @brief Fill the buffer
  72  * @return Number of bytes read
  73  */
  74 static size_t fill(void) {
  75   int n = read(inputfd, input_buffer, sizeof input_buffer);
  76
  77   if(n < 0)
  78     fatal(errno, "reading from %s", path);
  79   return n;
  80 }
  81
  82 /** @brief Write an 8-bit word */
  83 static inline void output_8(int n) {
  84   if(putc(n, outputfp) < 0)
  85     fatal(errno, "decoding %s: output error", path);
  86 }
  87
  88 /** @brief Write a 16-bit word in bigendian format */
  89 static inline void output_16(uint16_t n) {
  90   if(putc(n >> 8, outputfp) < 0
  91      || putc(n, outputfp) < 0)
  92     fatal(errno, "decoding %s: output error", path);
  93 }
  94
  95 /** @brief Write a 24-bit word in bigendian format */
  96 static inline void output_24(uint32_t n) {
  97   if(putc(n >> 16, outputfp) < 0
  98      || putc(n >> 8, outputfp) < 0
  99      || putc(n, outputfp) < 0)
 100     fatal(errno, "decoding %s: output error", path);
 101 }
 102
 103 /** @brief Write a 32-bit word in bigendian format */
 104 static inline void output_32(uint32_t n) {
 105   if(putc(n >> 24, outputfp) < 0
 106      || putc(n >> 16, outputfp) < 0
 107      || putc(n >> 8, outputfp) < 0
 108      || putc(n, outputfp) < 0)
 109     fatal(errno, "decoding %s: output error", path);
 110 }
 111
 112 /** @brief Write a block header
 113  * @param rate Sample rate in Hz
 114  * @param channels Channel count (currently only 1 or 2 supported)
 115  * @param bits Bits per sample (must be a multiple of 8, no more than 64)
 116  * @param nbytes Total number of data bytes
 117  * @param endian @ref ENDIAN_BIG or @ref ENDIAN_LITTLE
 118  *
 119  * Checks that the sample format is a supported one (so other calls do not have
 120  * to) and calls fatal() on error.
 121  */
 122 static void output_header(int rate,
 123                           int channels,
 124                           int bits,
 125                           int nbytes,
 126                           int endian) {
 127   struct stream_header header;
 128
 129   if(bits <= 0 || bits % 8 || bits > 64)
 130     fatal(0, "decoding %s: unsupported sample size %d bits", path, bits);
 131   if(channels <= 0 || channels > 2)
 132     fatal(0, "decoding %s: unsupported channel count %d", path, channels);
 133   if(rate <= 0)
 134     fatal(0, "decoding %s: nonsensical sample rate %dHz", path, rate);
 135   header.rate = rate;
 136   header.bits = bits;
 137   header.channels = channels;
 138   header.endian = endian;
 139   header.nbytes = nbytes;
 140   if(fwrite(&header, sizeof header, 1, outputfp) < 1)
 141     fatal(errno, "decoding %s: writing format header", path);
 142 }
 143
 144 /** @brief Dithering state
 145  * Filched from mpg321, which credits it to Robert Leslie */
 146 struct audio_dither {
 147   mad_fixed_t error[3];
 148   mad_fixed_t random;
 149 };
 150
 151 /** @brief 32-bit PRNG
 152  * Filched from mpg321, which credits it to Robert Leslie */
 153 static inline unsigned long prng(unsigned long state)
 154 {
 155   return (state * 0x0019660dL + 0x3c6ef35fL) & 0xffffffffL;
 156 }
 157
 158 /** @brief Generic linear sample quantize and dither routine
 159  * Filched from mpg321, which credits it to Robert Leslie */
 160 #define bits 16
 161 static long audio_linear_dither(mad_fixed_t sample,
 162                                 struct audio_dither *dither) {
 163   unsigned int scalebits;
 164   mad_fixed_t output, mask, rnd;
 165
 166   enum {
 167     MIN = -MAD_F_ONE,
 168     MAX =  MAD_F_ONE - 1
 169   };
 170
 171   /* noise shape */
 172   sample += dither->error[0] - dither->error[1] + dither->error[2];
 173
 174   dither->error[2] = dither->error[1];
 175   dither->error[1] = dither->error[0] / 2;
 176
 177   /* bias */
 178   output = sample + (1L << (MAD_F_FRACBITS + 1 - bits - 1));
 179
 180   scalebits = MAD_F_FRACBITS + 1 - bits;
 181   mask = (1L << scalebits) - 1;
 182
 183   /* dither */
 184   rnd  = prng(dither->random);
 185   output += (rnd & mask) - (dither->random & mask);
 186
 187   dither->random = rnd;
 188
 189   /* clip */
 190   if (output > MAX) {
 191     output = MAX;
 192
 193     if (sample > MAX)
 194       sample = MAX;
 195   }
 196   else if (output < MIN) {
 197     output = MIN;
 198
 199     if (sample < MIN)
 200       sample = MIN;
 201   }
 202
 203   /* quantize */
 204   output &= ~mask;
 205
 206   /* error feedback */
 207   dither->error[0] = sample - output;
 208
 209   /* scale */
 210   return output >> scalebits;
 211 }
 212 #undef bits
 213
 214 /** @brief MP3 output callback */
 215 static enum mad_flow mp3_output(void attribute((unused)) *data,
 216                                 struct mad_header const *header,
 217                                 struct mad_pcm *pcm) {
 218   size_t n = pcm->length;
 219   const mad_fixed_t *l = pcm->samples[0], *r = pcm->samples[1];
 220   static struct audio_dither ld[1], rd[1];
 221
 222   output_header(header->samplerate,
 223                 pcm->channels,
 224                 16,
 225                 2 * pcm->channels * pcm->length,
 226                 ENDIAN_BIG);
 227   switch(pcm->channels) {
 228   case 1:
 229     while(n--)
 230       output_16(audio_linear_dither(*l++, ld));
 231     break;
 232   case 2:
 233     while(n--) {
 234       output_16(audio_linear_dither(*l++, ld));
 235       output_16(audio_linear_dither(*r++, rd));
 236     }
 237     break;
 238   }
 239   return MAD_FLOW_CONTINUE;
 240 }
 241
 242 /** @brief MP3 input callback */
 243 static enum mad_flow mp3_input(void attribute((unused)) *data,
 244                                struct mad_stream *stream) {
 245   const size_t n = fill();
 246
 247   if(!n)
 248     return MAD_FLOW_STOP;
 249   mad_stream_buffer(stream, (unsigned char *)input_buffer, n);
 250   return MAD_FLOW_CONTINUE;
 251 }
 252
 253
 254 /** @brief MP3 error callback */
 255 static enum mad_flow mp3_error(void attribute((unused)) *data,
 256                                struct mad_stream *stream,
 257                                struct mad_frame attribute((unused)) *frame) {
 258   if(0)
 259     /* Just generates pointless verbosity l-( */
 260     error(0, "decoding %s: %s (%#04x)",
 261           path, mad_stream_errorstr(stream), stream->error);
 262   return MAD_FLOW_CONTINUE;
 263 }
 264
 265 /** @brief MP3 decoder */
 266 static void decode_mp3(void) {
 267   struct mad_decoder mad[1];
 268
 269   open_input();
 270   mad_decoder_init(mad, 0/*data*/, mp3_input, 0/*header*/, 0/*filter*/,
 271                    mp3_output, mp3_error, 0/*message*/);
 272   if(mad_decoder_run(mad, MAD_DECODER_MODE_SYNC))
 273     exit(1);
 274   mad_decoder_finish(mad);
 275 }
 276
 277 /** @brief OGG decoder */
 278 static void decode_ogg(void) {
 279   FILE *fp;
 280   OggVorbis_File vf[1];
 281   int err;
 282   long n;
 283   int bitstream;
 284   vorbis_info *vi;
 285
 286   if(!(fp = fopen(path, "rb")))
 287     fatal(errno, "cannot open %s", path);
 288   /* There doesn't seem to be any standard function for mapping the error codes
 289    * to strings l-( */
 290   if((err = ov_open(fp, vf, 0/*initial*/, 0/*ibytes*/)))
 291     fatal(0, "ov_fopen %s: %d", path, err);
 292   if(!(vi = ov_info(vf, 0/*link*/)))
 293     fatal(0, "ov_info %s: failed", path);
 294   while((n = ov_read(vf, input_buffer, sizeof input_buffer, 1/*bigendianp*/,
 295                      2/*bytes/word*/, 1/*signed*/, &bitstream))) {
 296     if(n < 0)
 297       fatal(0, "ov_read %s: %ld", path, n);
 298     if(bitstream > 0)
 299       fatal(0, "only single-bitstream ogg files are supported");
 300     output_header(vi->rate, vi->channels, 16/*bits*/, n, ENDIAN_BIG);
 301     if(fwrite(input_buffer, 1, n, outputfp) < (size_t)n)
 302       fatal(errno, "decoding %s: writing sample data", path);
 303   }
 304 }
 305
 306 /** @brief Sample data callback used by decode_wav() */
 307 static int wav_write(struct wavfile attribute((unused)) *f,
 308                      const char *data,
 309                      size_t nbytes,
 310                      void attribute((unused)) *u) {
 311   if(fwrite(data, 1, nbytes, outputfp) < nbytes)
 312     fatal(errno, "decoding %s: writing sample data", path);
 313   return 0;
 314 }
 315
 316 /** @brief WAV file decoder */
 317 static void decode_wav(void) {
 318   struct wavfile f[1];
 319   int err;
 320
 321   if((err = wav_init(f, path)))
 322     fatal(err, "opening %s", path);
 323   output_header(f->rate, f->channels, f->bits, f->datasize, ENDIAN_LITTLE);
 324   if((err = wav_data(f, wav_write, 0)))
 325     fatal(err, "error decoding %s", path);
 326 }
 327
 328 /** @brief Metadata callback for FLAC decoder
 329  *
 330  * This is a no-op here.
 331  */
 332 static void flac_metadata(const FLAC__FileDecoder attribute((unused)) *decoder,
 333                           const FLAC__StreamMetadata attribute((unused)) *metadata,
 334                           void attribute((unused)) *client_data) {
 335 }
 336
 337 /** @brief Error callback for FLAC decoder */
 338 static void flac_error(const FLAC__FileDecoder attribute((unused)) *decoder,
 339                        FLAC__StreamDecoderErrorStatus status,
 340                        void attribute((unused)) *client_data) {
 341   fatal(0, "error decoding %s: %s", path,
 342         FLAC__StreamDecoderErrorStatusString[status]);
 343 }
 344
 345 /** @brief Write callback for FLAC decoder */
 346 static FLAC__StreamDecoderWriteStatus flac_write
 347     (const FLAC__FileDecoder attribute((unused)) *decoder,
 348      const FLAC__Frame *frame,
 349      const FLAC__int32 *const buffer[],
 350      void attribute((unused)) *client_data) {
 351   size_t n, c;
 352
 353   output_header(frame->header.sample_rate,
 354                 frame->header.channels,
 355                 frame->header.bits_per_sample,
 356                 (frame->header.channels * frame->header.blocksize
 357                  * frame->header.bits_per_sample) / 8,
 358                 ENDIAN_BIG);
 359   for(n = 0; n < frame->header.blocksize; ++n) {
 360     for(c = 0; c < frame->header.channels; ++c) {
 361       switch(frame->header.bits_per_sample) {
 362       case 8: output_8(buffer[c][n]); break;
 363       case 16: output_16(buffer[c][n]); break;
 364       case 24: output_24(buffer[c][n]); break;
 365       case 32: output_32(buffer[c][n]); break;
 366       }
 367     }
 368   }
 369   return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
 370 }
 371
 372
 373 /** @brief FLAC file decoder */
 374 static void decode_flac(void) {
 375   FLAC__FileDecoder *fd = 0;
 376   FLAC__FileDecoderState fs;
 377
 378   if(!(fd = FLAC__file_decoder_new()))
 379     fatal(0, "FLAC__file_decoder_new failed");
 380   if(!(FLAC__file_decoder_set_filename(fd, path)))
 381     fatal(0, "FLAC__file_set_filename failed");
 382   FLAC__file_decoder_set_metadata_callback(fd, flac_metadata);
 383   FLAC__file_decoder_set_error_callback(fd, flac_error);
 384   FLAC__file_decoder_set_write_callback(fd, flac_write);
 385   if((fs = FLAC__file_decoder_init(fd)))
 386     fatal(0, "FLAC__file_decoder_init: %s", FLAC__FileDecoderStateString[fs]);
 387   FLAC__file_decoder_process_until_end_of_file(fd);
 388 }
 389
 390 /** @brief Lookup table of decoders */
 391 static const struct decoder decoders[] = {
 392   { "*.mp3", decode_mp3 },
 393   { "*.MP3", decode_mp3 },
 394   { "*.ogg", decode_ogg },
 395   { "*.OGG", decode_ogg },
 396   { "*.flac", decode_flac },
 397   { "*.FLAC", decode_flac },
 398   { "*.wav", decode_wav },
 399   { "*.WAV", decode_wav },
 400   { 0, 0 }
 401 };
 402
 403 static const struct option options[] = {
 404   { "help", no_argument, 0, 'h' },
 405   { "version", no_argument, 0, 'V' },
 406   { 0, 0, 0, 0 }
 407 };
 408
 409 /* Display usage message and terminate. */
 410 static void help(void) {
 411   xprintf("Usage:\n"
 412           "  disorder-decode [OPTIONS] PATH\n"
 413           "Options:\n"
 414           "  --help, -h              Display usage message\n"
 415           "  --version, -V           Display version number\n"
 416           "\n"
 417           "Audio decoder for DisOrder.  Only intended to be used by speaker\n"
 418           "process, not for normal users.\n");
 419   xfclose(stdout);
 420   exit(0);
 421 }
 422
 423 /* Display version number and terminate. */
 424 static void version(void) {
 425   xprintf("disorder-decode version %s\n", disorder_version_string);
 426   xfclose(stdout);
 427   exit(0);
 428 }
 429
 430 int main(int argc, char **argv) {
 431   int n;
 432   const char *e;
 433
 434   set_progname(argv);
 435   if(!setlocale(LC_CTYPE, "")) fatal(errno, "calling setlocale");
 436   while((n = getopt_long(argc, argv, "hV", options, 0)) >= 0) {
 437     switch(n) {
 438     case 'h': help();
 439     case 'V': version();
 440     default: fatal(0, "invalid option");
 441     }
 442   }
 443   if(optind >= argc)
 444     fatal(0, "missing filename");
 445   if(optind + 1 < argc)
 446     fatal(0, "excess arguments");
 447   if((e = getenv("DISORDER_RAW_FD"))) {
 448     if(!(outputfp = fdopen(atoi(e), "wb")))
 449       fatal(errno, "fdopen");
 450   } else
 451     outputfp = stdout;
 452   path = argv[optind];
 453   for(n = 0;
 454       decoders[n].pattern
 455         && fnmatch(decoders[n].pattern, path, 0) != 0;
 456       ++n)
 457     ;
 458   if(!decoders[n].pattern)
 459     fatal(0, "cannot determine file type for %s", path);
 460   decoders[n].decode();
 461   xfclose(outputfp);
 462   return 0;
 463 }
 464
 465 /*
 466 Local Variables:
 467 c-basic-offset:2
 468 comment-column:40
 469 fill-column:79
 470 indent-tabs-mode:nil
 471 End:
 472 */