apps/codecs/mpa.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2005 Dave Chapman
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21
  22 #include "codeclib.h"
  23 #include <codecs/libmad/mad.h>
  24 #include <inttypes.h>
  25
  26 CODEC_HEADER
  27
  28 #if NUM_CORES > 1 && !defined(MPEGPLAYER)
  29 #define MPA_SYNTH_ON_COP
  30 #endif
  31
  32 struct mad_stream stream IBSS_ATTR;
  33 struct mad_frame frame IBSS_ATTR;
  34 struct mad_synth synth IBSS_ATTR;
  35
  36 #ifdef MPA_SYNTH_ON_COP
  37 volatile short die IBSS_ATTR = 0;          /*thread should die*/
  38
  39 #if (CONFIG_CPU == PP5024) || (CONFIG_CPU == PP5022)
  40 mad_fixed_t sbsample_prev[2][36][32] IBSS_ATTR;
  41 #else
  42 mad_fixed_t sbsample_prev[2][36][32] SHAREDBSS_ATTR;
  43 #endif
  44
  45 struct semaphore synth_done_sem IBSS_ATTR;
  46 struct semaphore synth_pending_sem IBSS_ATTR;
  47 #endif
  48
  49 #define INPUT_CHUNK_SIZE   8192
  50
  51 mad_fixed_t mad_frame_overlap[2][32][18] IBSS_ATTR;
  52 mad_fixed_t sbsample[2][36][32] IBSS_ATTR;
  53
  54 unsigned char mad_main_data[MAD_BUFFER_MDLEN] IBSS_ATTR;
  55 /* TODO: what latency does layer 1 have? */
  56 int mpeg_latency[3] = { 0, 481, 529 };
  57 int mpeg_framesize[3] = {384, 1152, 1152};
  58
  59 static void init_mad(void)
  60 {
  61     ci->memset(&stream, 0, sizeof(struct mad_stream));
  62     ci->memset(&frame, 0, sizeof(struct mad_frame));
  63     ci->memset(&synth, 0, sizeof(struct mad_synth));
  64
  65     ci->memset(&sbsample, 0, sizeof(sbsample));
  66
  67 #ifdef MPA_SYNTH_ON_COP
  68     frame.sbsample_prev = &sbsample_prev;
  69     ci->memset(&sbsample_prev, 0, sizeof(sbsample_prev));
  70 #else
  71     frame.sbsample_prev = &sbsample;
  72 #endif
  73
  74     frame.sbsample=&sbsample;
  75
  76     mad_stream_init(&stream);
  77     mad_frame_init(&frame);
  78     mad_synth_init(&synth);
  79
  80     /* We do this so libmad doesn't try to call codec_calloc() */
  81     ci->memset(mad_frame_overlap, 0, sizeof(mad_frame_overlap));
  82     frame.overlap = &mad_frame_overlap;
  83     stream.main_data = &mad_main_data;
  84
  85
  86 }
  87
  88 static int get_file_pos(int newtime)
  89 {
  90     int pos = -1;
  91     struct mp3entry *id3 = ci->id3;
  92
  93     if (id3->vbr) {
  94         /* Convert newtime and id3->length to seconds to
  95          * avoid overflow */
  96         unsigned int newtime_s = newtime/1000;
  97         unsigned int length_s  = id3->length/1000;
  98
  99         if (id3->has_toc) {
 100             /* Use the TOC to find the new position */
 101             unsigned int percent, remainder;
 102             int curtoc, nexttoc, plen;
 103
 104             percent = (newtime_s*100) / length_s;
 105             if (percent > 99)
 106                 percent = 99;
 107
 108             curtoc = id3->toc[percent];
 109
 110             if (percent < 99) {
 111                 nexttoc = id3->toc[percent+1];
 112             } else {
 113                 nexttoc = 256;
 114             }
 115
 116             pos = (id3->filesize/256)*curtoc;
 117
 118             /* Use the remainder to get a more accurate position */
 119             remainder   = (newtime_s*100) % length_s;
 120             remainder   = (remainder*100) / length_s;
 121             plen        = (nexttoc - curtoc)*(id3->filesize/256);
 122             pos        += (plen/100)*remainder;
 123         } else {
 124             /* No TOC exists, estimate the new position */
 125             pos = (id3->filesize / length_s) * newtime_s;
 126         }
 127     } else if (id3->bitrate) {
 128         pos = newtime * (id3->bitrate / 8);
 129     } else {
 130         return -1;
 131     }
 132
 133     /* Don't seek right to the end of the file so that we can
 134        transition properly to the next song */
 135     if (pos >= (int)(id3->filesize - id3->id3v1len))
 136         pos = id3->filesize - id3->id3v1len - 1;
 137
 138     /* id3->filesize excludes id3->first_frame_offset, so add it now */
 139     pos += id3->first_frame_offset;
 140
 141     return pos;
 142 }
 143
 144 static void set_elapsed(struct mp3entry* id3)
 145 {
 146     unsigned long offset = id3->offset > id3->first_frame_offset ?
 147         id3->offset - id3->first_frame_offset : 0;
 148
 149     if ( id3->vbr ) {
 150         if ( id3->has_toc ) {
 151             /* calculate elapsed time using TOC */
 152             int i;
 153             unsigned int remainder, plen, relpos, nextpos;
 154
 155             /* find wich percent we're at */
 156             for (i=0; i<100; i++ )
 157                 if ( offset < id3->toc[i] * (id3->filesize / 256) )
 158                     break;
 159
 160             i--;
 161             if (i < 0)
 162                 i = 0;
 163
 164             relpos = id3->toc[i];
 165
 166             if (i < 99)
 167                 nextpos = id3->toc[i+1];
 168             else
 169                 nextpos = 256;
 170
 171             remainder = offset - (relpos * (id3->filesize / 256));
 172
 173             /* set time for this percent (divide before multiply to prevent
 174                overflow on long files. loss of precision is negligible on
 175                short files) */
 176             id3->elapsed = i * (id3->length / 100);
 177
 178             /* calculate remainder time */
 179             plen = (nextpos - relpos) * (id3->filesize / 256);
 180             id3->elapsed += (((remainder * 100) / plen) *
 181                              (id3->length / 10000));
 182         }
 183         else {
 184             /* no TOC exists. set a rough estimate using average bitrate */
 185             int tpk = id3->length /
 186                 ((id3->filesize - id3->first_frame_offset - id3->id3v1len) /
 187                 1024);
 188             id3->elapsed = offset / 1024 * tpk;
 189         }
 190     }
 191     else
 192     {
 193         /* constant bitrate, use exact calculation */
 194         if (id3->bitrate != 0)
 195             id3->elapsed = offset / (id3->bitrate / 8);
 196     }
 197 }
 198
 199 #ifdef MPA_SYNTH_ON_COP
 200
 201 /*
 202  * Run the synthesis filter on the COProcessor
 203  */
 204
 205 static int mad_synth_thread_stack[DEFAULT_STACK_SIZE/sizeof(int)] IBSS_ATTR;
 206
 207 static const unsigned char * const mad_synth_thread_name = "mp3dec";
 208 static unsigned int mad_synth_thread_id = 0;
 209
 210
 211 static void mad_synth_thread(void)
 212 {
 213     while(1) {
 214         ci->semaphore_release(&synth_done_sem);
 215         ci->semaphore_wait(&synth_pending_sem);
 216
 217         if(die)
 218             break;
 219
 220         mad_synth_frame(&synth, &frame);
 221     }
 222 }
 223
 224 /* wait for the synth thread to go idle which indicates a PCM frame has been
 225  * synthesized */
 226 static inline void mad_synth_thread_wait_pcm(void)
 227 {
 228     ci->semaphore_wait(&synth_done_sem);
 229 }
 230
 231 /* increment the done semaphore - used after a wait for idle to preserve the
 232  * semaphore count */
 233 static inline void mad_synth_thread_unwait_pcm(void)
 234 {
 235     ci->semaphore_release(&synth_done_sem);
 236 }
 237
 238 /* after synth thread has gone idle - switch decoded frames and commence
 239  * synthesis on it */
 240 static void mad_synth_thread_ready(void)
 241 {
 242     mad_fixed_t (*temp)[2][36][32];
 243
 244     /*circular buffer that holds 2 frames' samples*/
 245     temp=frame.sbsample;
 246     frame.sbsample = frame.sbsample_prev;
 247     frame.sbsample_prev=temp;
 248
 249     ci->semaphore_release(&synth_pending_sem);
 250 }
 251
 252 static bool mad_synth_thread_create(void)
 253 {
 254     ci->semaphore_init(&synth_done_sem, 1, 0);
 255     ci->semaphore_init(&synth_pending_sem, 1, 0);
 256
 257     mad_synth_thread_id = ci->create_thread(mad_synth_thread,
 258                             mad_synth_thread_stack,
 259                             sizeof(mad_synth_thread_stack), 0,
 260                             mad_synth_thread_name
 261                             IF_PRIO(, PRIORITY_PLAYBACK)
 262                             IF_COP(, COP));
 263
 264     if (mad_synth_thread_id == 0)
 265         return false;
 266
 267     return true;
 268 }
 269
 270 static void mad_synth_thread_quit(void)
 271 {
 272     /*mop up COP thread*/
 273     die=1;
 274     ci->semaphore_release(&synth_pending_sem);
 275     ci->thread_wait(mad_synth_thread_id);
 276     ci->cpucache_invalidate();
 277 }
 278 #else
 279 static inline void mad_synth_thread_ready(void)
 280 {
 281      mad_synth_frame(&synth, &frame);
 282 }
 283
 284 static inline bool mad_synth_thread_create(void)
 285 {
 286     return true;
 287 }
 288
 289 static inline void mad_synth_thread_quit(void)
 290 {
 291 }
 292
 293 static inline void mad_synth_thread_wait_pcm(void)
 294 {
 295 }
 296
 297 static inline void mad_synth_thread_unwait_pcm(void)
 298 {
 299 }
 300 #endif /* MPA_SYNTH_ON_COP */
 301
 302 /* this is the codec entry point */
 303 enum codec_status codec_main(void)
 304 {
 305     int status;
 306     size_t size;
 307     int file_end;
 308     int samples_to_skip; /* samples to skip in total for this file (at start) */
 309     char *inputbuffer;
 310     int64_t samplesdone;
 311     int stop_skip, start_skip;
 312     int current_stereo_mode = -1;
 313     unsigned long current_frequency = 0;
 314     int framelength;
 315     int padding = MAD_BUFFER_GUARD; /* to help mad decode the last frame */
 316
 317     if (codec_init())
 318         return CODEC_ERROR;
 319
 320     /* Create a decoder instance */
 321
 322     ci->configure(DSP_SET_SAMPLE_DEPTH, MAD_F_FRACBITS);
 323
 324     /*does nothing on 1 processor systems except return true*/
 325     if(!mad_synth_thread_create())
 326         return CODEC_ERROR;
 327
 328 next_track:
 329
 330     status = CODEC_OK;
 331
 332     /* Reinitializing seems to be necessary to avoid playback quircks when seeking. */
 333     init_mad();
 334
 335     file_end = 0;
 336     while (!*ci->taginfo_ready && !ci->stop_codec)
 337         ci->sleep(1);
 338
 339     ci->configure(DSP_SWITCH_FREQUENCY, ci->id3->frequency);
 340     current_frequency = ci->id3->frequency;
 341     codec_set_replaygain(ci->id3);
 342
 343     if (ci->id3->offset) {
 344         ci->seek_buffer(ci->id3->offset);
 345         set_elapsed(ci->id3);
 346     }
 347     else
 348         ci->seek_buffer(ci->id3->first_frame_offset);
 349
 350     if (ci->id3->lead_trim >= 0 && ci->id3->tail_trim >= 0) {
 351         stop_skip = ci->id3->tail_trim - mpeg_latency[ci->id3->layer];
 352         if (stop_skip < 0) stop_skip = 0;
 353         start_skip = ci->id3->lead_trim + mpeg_latency[ci->id3->layer];
 354     } else {
 355         stop_skip = 0;
 356         /* We want to skip this amount anyway */
 357         start_skip = mpeg_latency[ci->id3->layer];
 358     }
 359
 360     /* Libmad will not decode the last frame without 8 bytes of extra padding
 361        in the buffer. So, we can trick libmad into not decoding the last frame
 362        if we are to skip it entirely and then cut the appropriate samples from
 363        final frame that we did decode. Note, if all tags (ID3, APE) are not
 364        properly stripped from the end of the file, this trick will not work. */
 365     if (stop_skip >= mpeg_framesize[ci->id3->layer]) {
 366         padding = 0;
 367         stop_skip -= mpeg_framesize[ci->id3->layer];
 368     } else {
 369         padding = MAD_BUFFER_GUARD;
 370     }
 371
 372     samplesdone = ((int64_t)ci->id3->elapsed) * current_frequency / 1000;
 373
 374     /* Don't skip any samples unless we start at the beginning. */
 375     if (samplesdone > 0)
 376         samples_to_skip = 0;
 377     else
 378         samples_to_skip = start_skip;
 379
 380     framelength = 0;
 381
 382     /* This is the decoding loop. */
 383     while (1) {
 384         ci->yield();
 385         if (ci->stop_codec || ci->new_track)
 386             break;
 387
 388         if (ci->seek_time) {
 389             int newpos;
 390
 391             /*make sure the synth thread is idle before seeking - MT only*/
 392             mad_synth_thread_wait_pcm();
 393             mad_synth_thread_unwait_pcm();
 394
 395             samplesdone = ((int64_t)(ci->seek_time-1))*current_frequency/1000;
 396
 397             if (ci->seek_time-1 == 0) {
 398                 newpos = ci->id3->first_frame_offset;
 399                 samples_to_skip = start_skip;
 400             } else {
 401                 newpos = get_file_pos(ci->seek_time-1);
 402                 samples_to_skip = 0;
 403             }
 404
 405             if (!ci->seek_buffer(newpos))
 406                 break;
 407             ci->seek_complete();
 408             init_mad();
 409             framelength = 0;
 410         }
 411
 412         /* Lock buffers */
 413         if (stream.error == 0) {
 414             inputbuffer = ci->request_buffer(&size, INPUT_CHUNK_SIZE);
 415             if (size == 0 || inputbuffer == NULL)
 416                 break;
 417             mad_stream_buffer(&stream, (unsigned char *)inputbuffer,
 418                               size + padding);
 419         }
 420
 421         if (mad_frame_decode(&frame, &stream)) {
 422             if (stream.error == MAD_FLAG_INCOMPLETE
 423                 || stream.error == MAD_ERROR_BUFLEN) {
 424                 /* This makes the codec support partially corrupted files */
 425                 if (file_end == 30)
 426                     break;
 427
 428                 /* Fill the buffer */
 429                 if (stream.next_frame)
 430                     ci->advance_buffer_loc((void *)stream.next_frame);
 431                 else
 432                     ci->advance_buffer(size);
 433                 stream.error = 0;
 434                 file_end++;
 435                 continue;
 436             } else if (MAD_RECOVERABLE(stream.error)) {
 437                 continue;
 438             } else {
 439                 /* Some other unrecoverable error */
 440                 status = CODEC_ERROR;
 441                 break;
 442             }
 443             break;
 444         }
 445
 446         file_end = 0;
 447
 448         /* Do the pcmbuf insert here. Note, this is the PREVIOUS frame's pcm
 449            data (not the one just decoded above). When we exit the decoding
 450            loop we will need to process the final frame that was decoded. */
 451         mad_synth_thread_wait_pcm();
 452
 453         if (framelength > 0) {
 454
 455             /* In case of a mono file, the second array will be ignored. */
 456             ci->pcmbuf_insert(&synth.pcm.samples[0][samples_to_skip],
 457                               &synth.pcm.samples[1][samples_to_skip],
 458                               framelength);
 459
 460             /* Only skip samples for the first frame added. */
 461             samples_to_skip = 0;
 462         }
 463
 464         /* Initiate PCM synthesis on the COP (MT) or perform it here (ST) */
 465         mad_synth_thread_ready();
 466
 467         /* Check if sample rate and stereo settings changed in this frame. */
 468         if (frame.header.samplerate != current_frequency) {
 469             current_frequency = frame.header.samplerate;
 470             ci->configure(DSP_SWITCH_FREQUENCY, current_frequency);
 471         }
 472         if (MAD_NCHANNELS(&frame.header) == 2) {
 473             if (current_stereo_mode != STEREO_NONINTERLEAVED) {
 474                 ci->configure(DSP_SET_STEREO_MODE, STEREO_NONINTERLEAVED);
 475                 current_stereo_mode = STEREO_NONINTERLEAVED;
 476             }
 477         } else {
 478             if (current_stereo_mode != STEREO_MONO) {
 479                 ci->configure(DSP_SET_STEREO_MODE, STEREO_MONO);
 480                 current_stereo_mode = STEREO_MONO;
 481             }
 482         }
 483
 484         if (stream.next_frame)
 485             ci->advance_buffer_loc((void *)stream.next_frame);
 486         else
 487             ci->advance_buffer(size);
 488
 489         framelength = synth.pcm.length - samples_to_skip;
 490         if (framelength < 0) {
 491             framelength = 0;
 492             samples_to_skip -= synth.pcm.length;
 493         }
 494
 495         samplesdone += framelength;
 496         ci->set_elapsed((samplesdone * 1000) / current_frequency);
 497     }
 498
 499     /* wait for synth idle - MT only*/
 500     mad_synth_thread_wait_pcm();
 501     mad_synth_thread_unwait_pcm();
 502
 503     /* Finish the remaining decoded frame.
 504        Cut the required samples from the end. */
 505     if (framelength > stop_skip){
 506         ci->pcmbuf_insert(synth.pcm.samples[0], synth.pcm.samples[1],
 507                           framelength - stop_skip);
 508     }
 509
 510     if (ci->request_next_track())
 511         goto next_track;
 512
 513     /*mop up COP thread - MT only*/
 514     mad_synth_thread_quit();
 515
 516     return status;
 517 }