apps/metadata/mp4.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2005 Magnus Holmgren
  11  *
  12  * All files in this archive are subject to the GNU General Public License.
  13  * See the file COPYING in the source tree root for full license agreement.
  14  *
  15  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  16  * KIND, either express or implied.
  17  *
  18  ****************************************************************************/
  19 #include <stdio.h>
  20 #include <string.h>
  21 #include <stdlib.h>
  22 #include <ctype.h>
  23 #include <inttypes.h>
  24
  25 #include "system.h"
  26 #include "errno.h"
  27 #include "id3.h"
  28 #include "metadata_common.h"
  29 #include "logf.h"
  30 #include "debug.h"
  31 #include "replaygain.h"
  32 #include "atoi.h"
  33
  34 #define MP4_ID(a, b, c, d)  (((a) << 24) | ((b) << 16) | ((c) << 8) | (d))
  35
  36 #define MP4_3gp6 MP4_ID('3', 'g', 'p', '6')
  37 #define MP4_aART MP4_ID('a', 'A', 'R', 'T')
  38 #define MP4_alac MP4_ID('a', 'l', 'a', 'c')
  39 #define MP4_calb MP4_ID(0xa9, 'a', 'l', 'b')
  40 #define MP4_cART MP4_ID(0xa9, 'A', 'R', 'T')
  41 #define MP4_cgrp MP4_ID(0xa9, 'g', 'r', 'p')
  42 #define MP4_cgen MP4_ID(0xa9, 'g', 'e', 'n')
  43 #define MP4_cnam MP4_ID(0xa9, 'n', 'a', 'm')
  44 #define MP4_cwrt MP4_ID(0xa9, 'w', 'r', 't')
  45 #define MP4_ccmt MP4_ID(0xa9, 'c', 'm', 't')
  46 #define MP4_cday MP4_ID(0xa9, 'd', 'a', 'y')
  47 #define MP4_disk MP4_ID('d', 'i', 's', 'k')
  48 #define MP4_esds MP4_ID('e', 's', 'd', 's')
  49 #define MP4_ftyp MP4_ID('f', 't', 'y', 'p')
  50 #define MP4_gnre MP4_ID('g', 'n', 'r', 'e')
  51 #define MP4_hdlr MP4_ID('h', 'd', 'l', 'r')
  52 #define MP4_ilst MP4_ID('i', 'l', 's', 't')
  53 #define MP4_M4A  MP4_ID('M', '4', 'A', ' ')
  54 #define MP4_M4B  MP4_ID('M', '4', 'B', ' ')
  55 #define MP4_mdat MP4_ID('m', 'd', 'a', 't')
  56 #define MP4_mdia MP4_ID('m', 'd', 'i', 'a')
  57 #define MP4_mdir MP4_ID('m', 'd', 'i', 'r')
  58 #define MP4_meta MP4_ID('m', 'e', 't', 'a')
  59 #define MP4_minf MP4_ID('m', 'i', 'n', 'f')
  60 #define MP4_moov MP4_ID('m', 'o', 'o', 'v')
  61 #define MP4_mp4a MP4_ID('m', 'p', '4', 'a')
  62 #define MP4_mp42 MP4_ID('m', 'p', '4', '2')
  63 #define MP4_qt   MP4_ID('q', 't', ' ', ' ')
  64 #define MP4_soun MP4_ID('s', 'o', 'u', 'n')
  65 #define MP4_stbl MP4_ID('s', 't', 'b', 'l')
  66 #define MP4_stsd MP4_ID('s', 't', 's', 'd')
  67 #define MP4_stts MP4_ID('s', 't', 't', 's')
  68 #define MP4_trak MP4_ID('t', 'r', 'a', 'k')
  69 #define MP4_trkn MP4_ID('t', 'r', 'k', 'n')
  70 #define MP4_udta MP4_ID('u', 'd', 't', 'a')
  71 #define MP4_extra MP4_ID('-', '-', '-', '-')
  72
  73 /* Read the tag data from an MP4 file, storing up to buffer_size bytes in
  74  * buffer.
  75  */
  76 static unsigned long read_mp4_tag(int fd, unsigned int size_left, char* buffer,
  77                                   unsigned int buffer_left)
  78 {
  79     unsigned int bytes_read = 0;
  80
  81     if (buffer_left == 0)
  82     {
  83         lseek(fd, size_left, SEEK_CUR);     /* Skip everything */
  84     }
  85     else
  86     {
  87         /* Skip the data tag header - maybe we should parse it properly? */
  88         lseek(fd, 16, SEEK_CUR);
  89         size_left -= 16;
  90
  91         if (size_left > buffer_left)
  92         {
  93             read(fd, buffer, buffer_left);
  94             lseek(fd, size_left - buffer_left, SEEK_CUR);
  95             bytes_read = buffer_left;
  96         }
  97         else
  98         {
  99             read(fd, buffer, size_left);
 100             bytes_read = size_left;
 101         }
 102     }
 103
 104     return bytes_read;
 105 }
 106
 107 /* Read a string tag from an MP4 file */
 108 static unsigned int read_mp4_tag_string(int fd, int size_left, char** buffer,
 109                                         unsigned int* buffer_left, char** dest)
 110 {
 111     unsigned int bytes_read = read_mp4_tag(fd, size_left, *buffer,
 112         *buffer_left > 0 ? *buffer_left - 1 : 0);
 113     unsigned int length = 0;
 114
 115     if (bytes_read)
 116     {
 117         (*buffer)[bytes_read] = 0;
 118         *dest = *buffer;
 119         length = strlen(*buffer) + 1;
 120         *buffer_left -= length;
 121         *buffer += length;
 122     }
 123     else
 124     {
 125         *dest = NULL;
 126     }
 127
 128     return length;
 129 }
 130
 131 static unsigned int read_mp4_atom(int fd, unsigned int* size,
 132                                   unsigned int* type, unsigned int size_left)
 133 {
 134     read_uint32be(fd, size);
 135     read_uint32be(fd, type);
 136
 137     if (*size == 1)
 138     {
 139         /* FAT32 doesn't support files this big, so something seems to
 140          * be wrong. (64-bit sizes should only be used when required.)
 141          */
 142         errno = EFBIG;
 143         *type = 0;
 144         return 0;
 145     }
 146
 147     if (*size > 0)
 148     {
 149         if (*size > size_left)
 150         {
 151             size_left = 0;
 152         }
 153         else
 154         {
 155             size_left -= *size;
 156         }
 157
 158         *size -= 8;
 159     }
 160     else
 161     {
 162         *size = size_left;
 163         size_left = 0;
 164     }
 165
 166     return size_left;
 167 }
 168
 169 static unsigned int read_mp4_length(int fd, unsigned int* size)
 170 {
 171     unsigned int length = 0;
 172     int bytes = 0;
 173     unsigned char c;
 174
 175     do
 176     {
 177         read(fd, &c, 1);
 178         bytes++;
 179         (*size)--;
 180         length = (length << 7) | (c & 0x7F);
 181     }
 182     while ((c & 0x80) && (bytes < 4) && (*size > 0));
 183
 184     return length;
 185 }
 186
 187 static bool read_mp4_esds(int fd, struct mp3entry* id3,
 188     unsigned int* size)
 189 {
 190     unsigned char buf[8];
 191     bool sbr = false;
 192
 193     lseek(fd, 4, SEEK_CUR);     /* Version and flags. */
 194     read(fd, buf, 1);           /* Verify ES_DescrTag. */
 195     *size -= 5;
 196
 197     if (*buf == 3)
 198     {
 199         /* read length */
 200         if (read_mp4_length(fd, size) < 20)
 201         {
 202             return sbr;
 203         }
 204
 205         lseek(fd, 3, SEEK_CUR);
 206         *size -= 3;
 207     }
 208     else
 209     {
 210         lseek(fd, 2, SEEK_CUR);
 211         *size -= 2;
 212     }
 213
 214     read(fd, buf, 1);           /* Verify DecoderConfigDescrTab. */
 215     *size -= 1;
 216
 217     if (*buf != 4)
 218     {
 219         return sbr;
 220     }
 221
 222     if (read_mp4_length(fd, size) < 13)
 223     {
 224         return sbr;
 225     }
 226
 227     lseek(fd, 13, SEEK_CUR);    /* Skip audio type, bit rates, etc. */
 228     read(fd, buf, 1);
 229     *size -= 14;
 230
 231     if (*buf != 5)              /* Verify DecSpecificInfoTag. */
 232     {
 233         return sbr;
 234     }
 235
 236     {
 237         static const int sample_rates[] =
 238         {
 239             96000, 88200, 64000, 48000, 44100, 32000,
 240             24000, 22050, 16000, 12000, 11025, 8000
 241         };
 242         unsigned long bits;
 243         unsigned int length;
 244         unsigned int index;
 245         unsigned int type;
 246
 247         /* Read the (leading part of the) decoder config. */
 248         length = read_mp4_length(fd, size);
 249         length = MIN(length, *size);
 250         length = MIN(length, sizeof(buf));
 251         memset(buf, 0, sizeof(buf));
 252         read(fd, buf, length);
 253         *size -= length;
 254
 255         /* Maybe time to write a simple read_bits function... */
 256
 257         /* Decoder config format:
 258          * Object type           - 5 bits
 259          * Frequency index       - 4 bits
 260          * Channel configuration - 4 bits
 261          */
 262         bits = get_long_be(buf);
 263         type = bits >> 27;              /* Object type - 5 bits */
 264         index = (bits >> 23) & 0xf;     /* Frequency index - 4 bits */
 265
 266         if (index < (sizeof(sample_rates) / sizeof(*sample_rates)))
 267         {
 268             id3->frequency = sample_rates[index];
 269         }
 270
 271         if (type == 5)
 272         {
 273             DEBUGF("MP4: SBR\n");
 274             unsigned int old_index = index;
 275
 276             sbr = true;
 277             index = (bits >> 15) & 0xf; /* Frequency index - 4 bits */
 278
 279             if (index == 15)
 280             {
 281                 /* 17 bits read so far... */
 282                 bits = get_long_be(&buf[2]);
 283                 id3->frequency = (bits >> 7) & 0x00ffffff;
 284             }
 285             else if (index < (sizeof(sample_rates) / sizeof(*sample_rates)))
 286             {
 287                 id3->frequency = sample_rates[index];
 288             }
 289
 290             if (old_index == index)
 291             {
 292                 /* Downsampled SBR */
 293                 id3->frequency *= 2;
 294             }
 295         }
 296         /* Skip 13 bits from above, plus 3 bits, then read 11 bits */
 297         else if ((length >= 4) && (((bits >> 5) & 0x7ff) == 0x2b7))
 298         {
 299             /* extensionAudioObjectType */
 300             DEBUGF("MP4: extensionAudioType\n");
 301             type = bits & 0x1f;         /* Object type - 5 bits*/
 302             bits = get_long_be(&buf[4]);
 303
 304             if (type == 5)
 305             {
 306                 sbr = bits >> 31;
 307
 308                 if (sbr)
 309                 {
 310                     unsigned int old_index = index;
 311
 312                     /* 1 bit read so far */
 313                     index = (bits >> 27) & 0xf; /* Frequency index - 4 bits */
 314
 315                     if (index == 15)
 316                     {
 317                         /* 5 bits read so far */
 318                         id3->frequency = (bits >> 3) & 0x00ffffff;
 319                     }
 320                     else if (index < (sizeof(sample_rates) / sizeof(*sample_rates)))
 321                     {
 322                         id3->frequency = sample_rates[index];
 323                     }
 324
 325                     if (old_index == index)
 326                     {
 327                         /* Downsampled SBR */
 328                         id3->frequency *= 2;
 329                     }
 330                 }
 331             }
 332         }
 333
 334         if (!sbr && (id3->frequency <= 24000) && (length <= 2))
 335         {
 336             /* Double the frequency for low-frequency files without a "long"
 337              * DecSpecificConfig header. The file may or may not contain SBR,
 338              * but here we guess it does if the header is short. This can
 339              * fail on some files, but it's the best we can do, short of
 340              * decoding (parts of) the file.
 341              */
 342             id3->frequency *= 2;
 343         }
 344     }
 345
 346     return sbr;
 347 }
 348
 349 static bool read_mp4_tags(int fd, struct mp3entry* id3,
 350                           unsigned int size_left)
 351 {
 352     unsigned int size;
 353     unsigned int type;
 354     unsigned int buffer_left = sizeof(id3->id3v2buf) + sizeof(id3->id3v1buf);
 355     char* buffer = id3->id3v2buf;
 356     bool cwrt = false;
 357
 358     do
 359     {
 360         size_left = read_mp4_atom(fd, &size, &type, size_left);
 361
 362         /* DEBUGF("Tag atom: '%c%c%c%c' (%d bytes left)\n", type >> 24 & 0xff,
 363             type >> 16 & 0xff, type >> 8 & 0xff, type & 0xff, size); */
 364
 365         switch (type)
 366         {
 367         case MP4_cnam:
 368             read_mp4_tag_string(fd, size, &buffer, &buffer_left,
 369                 &id3->title);
 370             break;
 371
 372         case MP4_cART:
 373             read_mp4_tag_string(fd, size, &buffer, &buffer_left,
 374                 &id3->artist);
 375             break;
 376
 377         case MP4_aART:
 378             read_mp4_tag_string(fd, size, &buffer, &buffer_left,
 379                 &id3->albumartist);
 380             break;
 381
 382         case MP4_cgrp:
 383             read_mp4_tag_string(fd, size, &buffer, &buffer_left,
 384                 &id3->grouping);
 385             break;
 386
 387         case MP4_calb:
 388             read_mp4_tag_string(fd, size, &buffer, &buffer_left,
 389                 &id3->album);
 390             break;
 391
 392         case MP4_cwrt:
 393             read_mp4_tag_string(fd, size, &buffer, &buffer_left,
 394                 &id3->composer);
 395             cwrt = false;
 396             break;
 397
 398         case MP4_ccmt:
 399             read_mp4_tag_string(fd, size, &buffer, &buffer_left,
 400                 &id3->comment);
 401             break;
 402
 403         case MP4_cday:
 404             read_mp4_tag_string(fd, size, &buffer, &buffer_left,
 405                                 &id3->year_string);
 406
 407             /* Try to parse it as a year, for the benefit of the database.
 408              */
 409             if(id3->year_string)
 410             {
 411                 id3->year = atoi(id3->year_string);
 412                 if (id3->year < 1900)
 413                 {
 414                     id3->year = 0;
 415                 }
 416             }
 417             else
 418                 id3->year = 0;
 419
 420             break;
 421
 422         case MP4_gnre:
 423             {
 424                 unsigned short genre;
 425
 426                 read_mp4_tag(fd, size, (char*) &genre, sizeof(genre));
 427                 id3->genre_string = id3_get_num_genre(betoh16(genre) - 1);
 428             }
 429             break;
 430
 431         case MP4_cgen:
 432             read_mp4_tag_string(fd, size, &buffer, &buffer_left,
 433                 &id3->genre_string);
 434             break;
 435
 436         case MP4_disk:
 437             {
 438                 unsigned short n[2];
 439
 440                 read_mp4_tag(fd, size, (char*) &n, sizeof(n));
 441                 id3->discnum = betoh16(n[1]);
 442             }
 443             break;
 444
 445         case MP4_trkn:
 446             {
 447                 unsigned short n[2];
 448
 449                 read_mp4_tag(fd, size, (char*) &n, sizeof(n));
 450                 id3->tracknum = betoh16(n[1]);
 451             }
 452             break;
 453
 454         case MP4_extra:
 455             {
 456                 char tag_name[TAG_NAME_LENGTH];
 457                 unsigned int sub_size;
 458
 459                 /* "mean" atom */
 460                 read_uint32be(fd, &sub_size);
 461                 size -= sub_size;
 462                 lseek(fd, sub_size - 4, SEEK_CUR);
 463                 /* "name" atom */
 464                 read_uint32be(fd, &sub_size);
 465                 size -= sub_size;
 466                 lseek(fd, 8, SEEK_CUR);
 467                 sub_size -= 12;
 468
 469                 if (sub_size > sizeof(tag_name) - 1)
 470                 {
 471                     read(fd, tag_name, sizeof(tag_name) - 1);
 472                     lseek(fd, sub_size - (sizeof(tag_name) - 1), SEEK_CUR);
 473                     tag_name[sizeof(tag_name) - 1] = 0;
 474                 }
 475                 else
 476                 {
 477                     read(fd, tag_name, sub_size);
 478                     tag_name[sub_size] = 0;
 479                 }
 480
 481                 if ((strcasecmp(tag_name, "composer") == 0) && !cwrt)
 482                 {
 483                     read_mp4_tag_string(fd, size, &buffer, &buffer_left,
 484                         &id3->composer);
 485                 }
 486                 else if (strcasecmp(tag_name, "iTunSMPB") == 0)
 487                 {
 488                     char value[TAG_VALUE_LENGTH];
 489                     char* value_p = value;
 490                     char* any;
 491                     unsigned int length = sizeof(value);
 492
 493                     read_mp4_tag_string(fd, size, &value_p, &length, &any);
 494                     id3->lead_trim = get_itunes_int32(value, 1);
 495                     id3->tail_trim = get_itunes_int32(value, 2);
 496                     DEBUGF("AAC: lead_trim %d, tail_trim %d\n",
 497                         id3->lead_trim, id3->tail_trim);
 498                 }
 499                 else
 500                 {
 501                     char* any;
 502                     unsigned int length = read_mp4_tag_string(fd, size,
 503                         &buffer, &buffer_left, &any);
 504
 505                     if (length > 0)
 506                     {
 507                         /* Re-use the read buffer as the dest buffer... */
 508                         buffer -= length;
 509                         buffer_left += length;
 510
 511                         if (parse_replaygain(tag_name, buffer, id3,
 512                             buffer, buffer_left) > 0)
 513                         {
 514                             /* Data used, keep it. */
 515                             buffer += length;
 516                             buffer_left -= length;
 517                         }
 518                     }
 519                 }
 520             }
 521             break;
 522
 523         default:
 524             lseek(fd, size, SEEK_CUR);
 525             break;
 526         }
 527     }
 528     while ((size_left > 0) && (errno == 0));
 529
 530     return true;
 531 }
 532
 533 static bool read_mp4_container(int fd, struct mp3entry* id3,
 534                                unsigned int size_left)
 535 {
 536     unsigned int size;
 537     unsigned int type;
 538     unsigned int handler = 0;
 539     bool rc = true;
 540
 541     do
 542     {
 543         size_left = read_mp4_atom(fd, &size, &type, size_left);
 544
 545         /* DEBUGF("Atom: '%c%c%c%c' (0x%08x, %d bytes left)\n",
 546             (type >> 24) & 0xff, (type >> 16) & 0xff, (type >> 8) & 0xff,
 547             type & 0xff, type, size); */
 548
 549         switch (type)
 550         {
 551         case MP4_ftyp:
 552             {
 553                 unsigned int id;
 554
 555                 read_uint32be(fd, &id);
 556                 size -= 4;
 557
 558                 if ((id != MP4_M4A) && (id != MP4_M4B) && (id != MP4_mp42)
 559                     && (id != MP4_qt) && (id != MP4_3gp6))
 560                 {
 561                     DEBUGF("Unknown MP4 file type: '%c%c%c%c'\n",
 562                         id >> 24 & 0xff, id >> 16 & 0xff, id >> 8 & 0xff,
 563                         id & 0xff);
 564                     return false;
 565                 }
 566             }
 567             break;
 568
 569         case MP4_meta:
 570             lseek(fd, 4, SEEK_CUR);  /* Skip version */
 571             size -= 4;
 572             /* Fall through */
 573
 574         case MP4_moov:
 575         case MP4_udta:
 576         case MP4_mdia:
 577         case MP4_stbl:
 578         case MP4_trak:
 579             rc = read_mp4_container(fd, id3, size);
 580             size = 0;
 581             break;
 582
 583         case MP4_ilst:
 584             if (handler == MP4_mdir)
 585             {
 586                 rc = read_mp4_tags(fd, id3, size);
 587                 size = 0;
 588             }
 589             break;
 590
 591         case MP4_minf:
 592             if (handler == MP4_soun)
 593             {
 594                 rc = read_mp4_container(fd, id3, size);
 595                 size = 0;
 596             }
 597             break;
 598
 599         case MP4_stsd:
 600             lseek(fd, 8, SEEK_CUR);
 601             size -= 8;
 602             rc = read_mp4_container(fd, id3, size);
 603             size = 0;
 604             break;
 605
 606         case MP4_hdlr:
 607             lseek(fd, 8, SEEK_CUR);
 608             read_uint32be(fd, &handler);
 609             size -= 12;
 610             /* DEBUGF("    Handler '%c%c%c%c'\n", handler >> 24 & 0xff,
 611                 handler >> 16 & 0xff, handler >> 8 & 0xff,handler & 0xff); */
 612             break;
 613
 614         case MP4_stts:
 615             {
 616                 unsigned int entries;
 617                 unsigned int i;
 618
 619                 lseek(fd, 4, SEEK_CUR);
 620                 read_uint32be(fd, &entries);
 621                 id3->samples = 0;
 622
 623                 for (i = 0; i < entries; i++)
 624                 {
 625                     unsigned int n;
 626                     unsigned int l;
 627
 628                     read_uint32be(fd, &n);
 629                     read_uint32be(fd, &l);
 630                     id3->samples += n * l;
 631                 }
 632
 633                 size = 0;
 634             }
 635             break;
 636
 637         case MP4_mp4a:
 638         case MP4_alac:
 639             {
 640                 unsigned int frequency;
 641
 642                 id3->codectype = (type == MP4_mp4a) ? AFMT_AAC : AFMT_ALAC;
 643                 lseek(fd, 22, SEEK_CUR);
 644                 read_uint32be(fd, &frequency);
 645                 size -= 26;
 646                 id3->frequency = frequency;
 647
 648                 if (type == MP4_mp4a)
 649                 {
 650                     unsigned int subsize;
 651                     unsigned int subtype;
 652
 653                     /* Get frequency from the decoder info tag, if possible. */
 654                     lseek(fd, 2, SEEK_CUR);
 655                     /* The esds atom is a part of the mp4a atom, so ignore
 656                      * the returned size (it's already accounted for).
 657                      */
 658                     read_mp4_atom(fd, &subsize, &subtype, size);
 659                     size -= 10;
 660
 661                     if (subtype == MP4_esds)
 662                     {
 663                         read_mp4_esds(fd, id3, &size);
 664                     }
 665                 }
 666             }
 667             break;
 668
 669         case MP4_mdat:
 670             id3->filesize = size;
 671             break;
 672
 673         default:
 674             break;
 675         }
 676
 677         lseek(fd, size, SEEK_CUR);
 678     }
 679     while (rc && (size_left > 0) && (errno == 0) && (id3->filesize == 0));
 680     /* Break on non-zero filesize, since Rockbox currently doesn't support
 681      * metadata after the mdat atom (which sets the filesize field).
 682      */
 683
 684     return rc;
 685 }
 686
 687 bool get_mp4_metadata(int fd, struct mp3entry* id3)
 688 {
 689     id3->codectype = AFMT_UNKNOWN;
 690     id3->filesize = 0;
 691     errno = 0;
 692
 693     if (read_mp4_container(fd, id3, filesize(fd)) && (errno == 0)
 694         && (id3->samples > 0) && (id3->frequency > 0)
 695         && (id3->filesize > 0))
 696     {
 697         if (id3->codectype == AFMT_UNKNOWN)
 698         {
 699             logf("Not an ALAC or AAC file");
 700             return false;
 701         }
 702
 703         id3->length = ((int64_t) id3->samples * 1000) / id3->frequency;
 704
 705         if (id3->length <= 0)
 706         {
 707             logf("mp4 length invalid!");
 708             return false;
 709         }
 710
 711         id3->bitrate = ((int64_t) id3->filesize * 8) / id3->length;
 712         DEBUGF("MP4 bitrate %d, frequency %ld Hz, length %ld ms\n",
 713             id3->bitrate, id3->frequency, id3->length);
 714     }
 715     else
 716     {
 717         logf("MP4 metadata error");
 718         DEBUGF("MP4 metadata error. errno %d, frequency %ld, filesize %ld\n",
 719             errno, id3->frequency, id3->filesize);
 720         return false;
 721     }
 722
 723     return true;
 724 }