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
  38 /* libFLAC has had an API change and stupidly taken away the old API */
  39 #if HAVE_FLAC_FILE_DECODER_H
  40 # include <FLAC/file_decoder.h>
  41 #else
  42 # include <FLAC/stream_decoder.h>
  43 #define FLAC__FileDecoder FLAC__StreamDecoder
  44 #define FLAC__FileDecoderState FLAC__StreamDecoderState
  45 #endif
  46
  47 #include "log.h"
  48 #include "syscalls.h"
  49 #include "defs.h"
  50 #include "wav.h"
  51 #include "speaker-protocol.h"
  52
  53 /** @brief Encoding lookup table type */
  54 struct decoder {
  55   /** @brief Glob pattern matching file */
  56   const char *pattern;
  57   /** @brief Decoder function */
  58   void (*decode)(void);
  59 };
  60
  61 /** @brief Input file */
  62 static int inputfd;
  63
  64 /** @brief Output file */
  65 static FILE *outputfp;
  66
  67 /** @brief Filename */
  68 static const char *path;
  69
  70 /** @brief Input buffer */
  71 static char input_buffer[1048576];
  72
  73 /** @brief Open the input file */
  74 static void open_input(void) {
  75   if((inputfd = open(path, O_RDONLY)) < 0)
  76     fatal(errno, "opening %s", path);
  77 }
  78
  79 /** @brief Fill the buffer
  80  * @return Number of bytes read
  81  */
  82 static size_t fill(void) {
  83   int n = read(inputfd, input_buffer, sizeof input_buffer);
  84
  85   if(n < 0)
  86     fatal(errno, "reading from %s", path);
  87   return n;
  88 }
  89
  90 /** @brief Write an 8-bit word */
  91 static inline void output_8(int n) {
  92   if(putc(n, outputfp) < 0)
  93     fatal(errno, "decoding %s: output error", path);
  94 }
  95
  96 /** @brief Write a 16-bit word in bigendian format */
  97 static inline void output_16(uint16_t n) {
  98   if(putc(n >> 8, outputfp) < 0
  99      || putc(n, outputfp) < 0)
 100     fatal(errno, "decoding %s: output error", path);
 101 }
 102
 103 /** @brief Write a 24-bit word in bigendian format */
 104 static inline void output_24(uint32_t n) {
 105   if(putc(n >> 16, outputfp) < 0
 106      || putc(n >> 8, outputfp) < 0
 107      || putc(n, outputfp) < 0)
 108     fatal(errno, "decoding %s: output error", path);
 109 }
 110
 111 /** @brief Write a 32-bit word in bigendian format */
 112 static inline void output_32(uint32_t n) {
 113   if(putc(n >> 24, outputfp) < 0
 114      || putc(n >> 16, outputfp) < 0
 115      || putc(n >> 8, outputfp) < 0
 116      || putc(n, outputfp) < 0)
 117     fatal(errno, "decoding %s: output error", path);
 118 }
 119
 120 /** @brief Write a block header
 121  * @param rate Sample rate in Hz
 122  * @param channels Channel count (currently only 1 or 2 supported)
 123  * @param bits Bits per sample (must be a multiple of 8, no more than 64)
 124  * @param nbytes Total number of data bytes
 125  * @param endian @ref ENDIAN_BIG or @ref ENDIAN_LITTLE
 126  *
 127  * Checks that the sample format is a supported one (so other calls do not have
 128  * to) and calls fatal() on error.
 129  */
 130 static void output_header(int rate,
 131                           int channels,
 132                           int bits,
 133                           int nbytes,
 134                           int endian) {
 135   struct stream_header header;
 136
 137   if(bits <= 0 || bits % 8 || bits > 64)
 138     fatal(0, "decoding %s: unsupported sample size %d bits", path, bits);
 139   if(channels <= 0 || channels > 2)
 140     fatal(0, "decoding %s: unsupported channel count %d", path, channels);
 141   if(rate <= 0)
 142     fatal(0, "decoding %s: nonsensical sample rate %dHz", path, rate);
 143   header.rate = rate;
 144   header.bits = bits;
 145   header.channels = channels;
 146   header.endian = endian;
 147   header.nbytes = nbytes;
 148   if(fwrite(&header, sizeof header, 1, outputfp) < 1)
 149     fatal(errno, "decoding %s: writing format header", path);
 150 }
 151
 152 /** @brief Dithering state
 153  * Filched from mpg321, which credits it to Robert Leslie */
 154 struct audio_dither {
 155   mad_fixed_t error[3];
 156   mad_fixed_t random;
 157 };
 158
 159 /** @brief 32-bit PRNG
 160  * Filched from mpg321, which credits it to Robert Leslie */
 161 static inline unsigned long prng(unsigned long state)
 162 {
 163   return (state * 0x0019660dL + 0x3c6ef35fL) & 0xffffffffL;
 164 }
 165
 166 /** @brief Generic linear sample quantize and dither routine
 167  * Filched from mpg321, which credits it to Robert Leslie */
 168 #define bits 16
 169 static long audio_linear_dither(mad_fixed_t sample,
 170                                 struct audio_dither *dither) {
 171   unsigned int scalebits;
 172   mad_fixed_t output, mask, rnd;
 173
 174   enum {
 175     MIN = -MAD_F_ONE,
 176     MAX =  MAD_F_ONE - 1
 177   };
 178
 179   /* noise shape */
 180   sample += dither->error[0] - dither->error[1] + dither->error[2];
 181
 182   dither->error[2] = dither->error[1];
 183   dither->error[1] = dither->error[0] / 2;
 184
 185   /* bias */
 186   output = sample + (1L << (MAD_F_FRACBITS + 1 - bits - 1));
 187
 188   scalebits = MAD_F_FRACBITS + 1 - bits;
 189   mask = (1L << scalebits) - 1;
 190
 191   /* dither */
 192   rnd  = prng(dither->random);
 193   output += (rnd & mask) - (dither->random & mask);
 194
 195   dither->random = rnd;
 196
 197   /* clip */
 198   if (output > MAX) {
 199     output = MAX;
 200
 201     if (sample > MAX)
 202       sample = MAX;
 203   }
 204   else if (output < MIN) {
 205     output = MIN;
 206
 207     if (sample < MIN)
 208       sample = MIN;
 209   }
 210
 211   /* quantize */
 212   output &= ~mask;
 213
 214   /* error feedback */
 215   dither->error[0] = sample - output;
 216
 217   /* scale */
 218   return output >> scalebits;
 219 }
 220 #undef bits
 221
 222 /** @brief MP3 output callback */
 223 static enum mad_flow mp3_output(void attribute((unused)) *data,
 224                                 struct mad_header const *header,
 225                                 struct mad_pcm *pcm) {
 226   size_t n = pcm->length;
 227   const mad_fixed_t *l = pcm->samples[0], *r = pcm->samples[1];
 228   static struct audio_dither ld[1], rd[1];
 229
 230   output_header(header->samplerate,
 231                 pcm->channels,
 232                 16,
 233                 2 * pcm->channels * pcm->length,
 234                 ENDIAN_BIG);
 235   switch(pcm->channels) {
 236   case 1:
 237     while(n--)
 238       output_16(audio_linear_dither(*l++, ld));
 239     break;
 240   case 2:
 241     while(n--) {
 242       output_16(audio_linear_dither(*l++, ld));
 243       output_16(audio_linear_dither(*r++, rd));
 244     }
 245     break;
 246   }
 247   return MAD_FLOW_CONTINUE;
 248 }
 249
 250 /** @brief MP3 input callback */
 251 static enum mad_flow mp3_input(void attribute((unused)) *data,
 252                                struct mad_stream *stream) {
 253   const size_t n = fill();
 254
 255   if(!n)
 256     return MAD_FLOW_STOP;
 257   mad_stream_buffer(stream, (unsigned char *)input_buffer, n);
 258   return MAD_FLOW_CONTINUE;
 259 }
 260
 261
 262 /** @brief MP3 error callback */
 263 static enum mad_flow mp3_error(void attribute((unused)) *data,
 264                                struct mad_stream *stream,
 265                                struct mad_frame attribute((unused)) *frame) {
 266   if(0)
 267     /* Just generates pointless verbosity l-( */
 268     error(0, "decoding %s: %s (%#04x)",
 269           path, mad_stream_errorstr(stream), stream->error);
 270   return MAD_FLOW_CONTINUE;
 271 }
 272
 273 /** @brief MP3 decoder */
 274 static void decode_mp3(void) {
 275   struct mad_decoder mad[1];
 276
 277   open_input();
 278   mad_decoder_init(mad, 0/*data*/, mp3_input, 0/*header*/, 0/*filter*/,
 279                    mp3_output, mp3_error, 0/*message*/);
 280   if(mad_decoder_run(mad, MAD_DECODER_MODE_SYNC))
 281     exit(1);
 282   mad_decoder_finish(mad);
 283 }
 284
 285 /** @brief OGG decoder */
 286 static void decode_ogg(void) {
 287   FILE *fp;
 288   OggVorbis_File vf[1];
 289   int err;
 290   long n;
 291   int bitstream;
 292   vorbis_info *vi;
 293
 294   if(!(fp = fopen(path, "rb")))
 295     fatal(errno, "cannot open %s", path);
 296   /* There doesn't seem to be any standard function for mapping the error codes
 297    * to strings l-( */
 298   if((err = ov_open(fp, vf, 0/*initial*/, 0/*ibytes*/)))
 299     fatal(0, "ov_fopen %s: %d", path, err);
 300   if(!(vi = ov_info(vf, 0/*link*/)))
 301     fatal(0, "ov_info %s: failed", path);
 302   while((n = ov_read(vf, input_buffer, sizeof input_buffer, 1/*bigendianp*/,
 303                      2/*bytes/word*/, 1/*signed*/, &bitstream))) {
 304     if(n < 0)
 305       fatal(0, "ov_read %s: %ld", path, n);
 306     if(bitstream > 0)
 307       fatal(0, "only single-bitstream ogg files are supported");
 308     output_header(vi->rate, vi->channels, 16/*bits*/, n, ENDIAN_BIG);
 309     if(fwrite(input_buffer, 1, n, outputfp) < (size_t)n)
 310       fatal(errno, "decoding %s: writing sample data", path);
 311   }
 312 }
 313
 314 /** @brief Sample data callback used by decode_wav() */
 315 static int wav_write(struct wavfile attribute((unused)) *f,
 316                      const char *data,
 317                      size_t nbytes,
 318                      void attribute((unused)) *u) {
 319   if(fwrite(data, 1, nbytes, outputfp) < nbytes)
 320     fatal(errno, "decoding %s: writing sample data", path);
 321   return 0;
 322 }
 323
 324 /** @brief WAV file decoder */
 325 static void decode_wav(void) {
 326   struct wavfile f[1];
 327   int err;
 328
 329   if((err = wav_init(f, path)))
 330     fatal(err, "opening %s", path);
 331   output_header(f->rate, f->channels, f->bits, f->datasize, ENDIAN_LITTLE);
 332   if((err = wav_data(f, wav_write, 0)))
 333     fatal(err, "error decoding %s", path);
 334 }
 335
 336 /** @brief Metadata callback for FLAC decoder
 337  *
 338  * This is a no-op here.
 339  */
 340 static void flac_metadata(const FLAC__FileDecoder attribute((unused)) *decoder,
 341                           const FLAC__StreamMetadata attribute((unused)) *metadata,
 342                           void attribute((unused)) *client_data) {
 343 }
 344
 345 /** @brief Error callback for FLAC decoder */
 346 static void flac_error(const FLAC__FileDecoder attribute((unused)) *decoder,
 347                        FLAC__StreamDecoderErrorStatus status,
 348                        void attribute((unused)) *client_data) {
 349   fatal(0, "error decoding %s: %s", path,
 350         FLAC__StreamDecoderErrorStatusString[status]);
 351 }
 352
 353 /** @brief Write callback for FLAC decoder */
 354 static FLAC__StreamDecoderWriteStatus flac_write
 355     (const FLAC__FileDecoder attribute((unused)) *decoder,
 356      const FLAC__Frame *frame,
 357      const FLAC__int32 *const buffer[],
 358      void attribute((unused)) *client_data) {
 359   size_t n, c;
 360
 361   output_header(frame->header.sample_rate,
 362                 frame->header.channels,
 363                 frame->header.bits_per_sample,
 364                 (frame->header.channels * frame->header.blocksize
 365                  * frame->header.bits_per_sample) / 8,
 366                 ENDIAN_BIG);
 367   for(n = 0; n < frame->header.blocksize; ++n) {
 368     for(c = 0; c < frame->header.channels; ++c) {
 369       switch(frame->header.bits_per_sample) {
 370       case 8: output_8(buffer[c][n]); break;
 371       case 16: output_16(buffer[c][n]); break;
 372       case 24: output_24(buffer[c][n]); break;
 373       case 32: output_32(buffer[c][n]); break;
 374       }
 375     }
 376   }
 377   return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
 378 }
 379
 380
 381 /** @brief FLAC file decoder */
 382 static void decode_flac(void) {
 383 #if HAVE_FLAC_FILE_DECODER_H
 384   FLAC__FileDecoder *fd = 0;
 385   FLAC__FileDecoderState fs;
 386
 387   if(!(fd = FLAC__file_decoder_new()))
 388     fatal(0, "FLAC__file_decoder_new failed");
 389   if(!(FLAC__file_decoder_set_filename(fd, path)))
 390     fatal(0, "FLAC__file_set_filename failed");
 391   FLAC__file_decoder_set_metadata_callback(fd, flac_metadata);
 392   FLAC__file_decoder_set_error_callback(fd, flac_error);
 393   FLAC__file_decoder_set_write_callback(fd, flac_write);
 394   if((fs = FLAC__file_decoder_init(fd)))
 395     fatal(0, "FLAC__file_decoder_init: %s", FLAC__FileDecoderStateString[fs]);
 396   FLAC__file_decoder_process_until_end_of_file(fd);
 397 #else
 398   FLAC__StreamDecoder *sd = 0;
 399   FLAC__StreamDecoderInitStatus is;
 400
 401   if((is = FLAC__stream_decoder_init_file(sd, path, flac_write, flac_metadata,
 402                                           flac_error, 0)))
 403     fatal(0, "FLAC__stream_decoder_init_file %s: %s",
 404           path, FLAC__StreamDecoderInitStatusString[is]);
 405 #endif
 406 }
 407
 408 /** @brief Lookup table of decoders */
 409 static const struct decoder decoders[] = {
 410   { "*.mp3", decode_mp3 },
 411   { "*.MP3", decode_mp3 },
 412   { "*.ogg", decode_ogg },
 413   { "*.OGG", decode_ogg },
 414   { "*.flac", decode_flac },
 415   { "*.FLAC", decode_flac },
 416   { "*.wav", decode_wav },
 417   { "*.WAV", decode_wav },
 418   { 0, 0 }
 419 };
 420
 421 static const struct option options[] = {
 422   { "help", no_argument, 0, 'h' },
 423   { "version", no_argument, 0, 'V' },
 424   { 0, 0, 0, 0 }
 425 };
 426
 427 /* Display usage message and terminate. */
 428 static void help(void) {
 429   xprintf("Usage:\n"
 430           "  disorder-decode [OPTIONS] PATH\n"
 431           "Options:\n"
 432           "  --help, -h              Display usage message\n"
 433           "  --version, -V           Display version number\n"
 434           "\n"
 435           "Audio decoder for DisOrder.  Only intended to be used by speaker\n"
 436           "process, not for normal users.\n");
 437   xfclose(stdout);
 438   exit(0);
 439 }
 440
 441 /* Display version number and terminate. */
 442 static void version(void) {
 443   xprintf("%s", disorder_version_string);
 444   xfclose(stdout);
 445   exit(0);
 446 }
 447
 448 int main(int argc, char **argv) {
 449   int n;
 450   const char *e;
 451
 452   set_progname(argv);
 453   if(!setlocale(LC_CTYPE, "")) fatal(errno, "calling setlocale");
 454   while((n = getopt_long(argc, argv, "hV", options, 0)) >= 0) {
 455     switch(n) {
 456     case 'h': help();
 457     case 'V': version();
 458     default: fatal(0, "invalid option");
 459     }
 460   }
 461   if(optind >= argc)
 462     fatal(0, "missing filename");
 463   if(optind + 1 < argc)
 464     fatal(0, "excess arguments");
 465   if((e = getenv("DISORDER_RAW_FD"))) {
 466     if(!(outputfp = fdopen(atoi(e), "wb")))
 467       fatal(errno, "fdopen");
 468   } else
 469     outputfp = stdout;
 470   path = argv[optind];
 471   for(n = 0;
 472       decoders[n].pattern
 473         && fnmatch(decoders[n].pattern, path, 0) != 0;
 474       ++n)
 475     ;
 476   if(!decoders[n].pattern)
 477     fatal(0, "cannot determine file type for %s", path);
 478   decoders[n].decode();
 479   xfclose(outputfp);
 480   return 0;
 481 }
 482
 483 /*
 484 Local Variables:
 485 c-basic-offset:2
 486 comment-column:40
 487 fill-column:79
 488 indent-tabs-mode:nil
 489 End:
 490 */