tools/qt-faststart.c

   1 /*
   2  * qt-faststart.c, v0.2
   3  * by Mike Melanson (melanson@pcisys.net)
   4  * This file is placed in the public domain. Use the program however you
   5  * see fit.
   6  *
   7  * This utility rearranges a Quicktime file such that the moov atom
   8  * is in front of the data, thus facilitating network streaming.
   9  *
  10  * To compile this program, start from the base directory from which you
  11  * are building FFmpeg and type:
  12  *  make tools/qt-faststart
  13  * The qt-faststart program will be built in the tools/ directory. If you
  14  * do not build the program in this manner, correct results are not
  15  * guaranteed, particularly on 64-bit platforms.
  16  * Invoke the program with:
  17  *  qt-faststart <infile.mov> <outfile.mov>
  18  *
  19  * Notes: Quicktime files can come in many configurations of top-level
  20  * atoms. This utility stipulates that the very last atom in the file needs
  21  * to be a moov atom. When given such a file, this utility will rearrange
  22  * the top-level atoms by shifting the moov atom from the back of the file
  23  * to the front, and patch the chunk offsets along the way. This utility
  24  * presently only operates on uncompressed moov atoms.
  25  */
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <inttypes.h>
  30
  31 #ifdef __MINGW32__
  32 #define fseeko(x,y,z)  fseeko64(x,y,z)
  33 #define ftello(x)      ftello64(x)
  34 #endif
  35
  36 #define BE_16(x) ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
  37 #define BE_32(x) ((((uint8_t*)(x))[0] << 24) | \
  38                   (((uint8_t*)(x))[1] << 16) | \
  39                   (((uint8_t*)(x))[2] << 8) | \
  40                    ((uint8_t*)(x))[3])
  41 #define BE_64(x) (((uint64_t)(((uint8_t*)(x))[0]) << 56) | \
  42                   ((uint64_t)(((uint8_t*)(x))[1]) << 48) | \
  43                   ((uint64_t)(((uint8_t*)(x))[2]) << 40) | \
  44                   ((uint64_t)(((uint8_t*)(x))[3]) << 32) | \
  45                   ((uint64_t)(((uint8_t*)(x))[4]) << 24) | \
  46                   ((uint64_t)(((uint8_t*)(x))[5]) << 16) | \
  47                   ((uint64_t)(((uint8_t*)(x))[6]) << 8) | \
  48                   ((uint64_t)((uint8_t*)(x))[7]))
  49
  50 #define BE_FOURCC( ch0, ch1, ch2, ch3 )             \
  51         ( (uint32_t)(unsigned char)(ch3) |          \
  52         ( (uint32_t)(unsigned char)(ch2) << 8 ) |   \
  53         ( (uint32_t)(unsigned char)(ch1) << 16 ) |  \
  54         ( (uint32_t)(unsigned char)(ch0) << 24 ) )
  55
  56 #define QT_ATOM BE_FOURCC
  57 /* top level atoms */
  58 #define FREE_ATOM QT_ATOM('f', 'r', 'e', 'e')
  59 #define JUNK_ATOM QT_ATOM('j', 'u', 'n', 'k')
  60 #define MDAT_ATOM QT_ATOM('m', 'd', 'a', 't')
  61 #define MOOV_ATOM QT_ATOM('m', 'o', 'o', 'v')
  62 #define PNOT_ATOM QT_ATOM('p', 'n', 'o', 't')
  63 #define SKIP_ATOM QT_ATOM('s', 'k', 'i', 'p')
  64 #define WIDE_ATOM QT_ATOM('w', 'i', 'd', 'e')
  65 #define PICT_ATOM QT_ATOM('P', 'I', 'C', 'T')
  66 #define FTYP_ATOM QT_ATOM('f', 't', 'y', 'p')
  67 #define UUID_ATOM QT_ATOM('u', 'u', 'i', 'd')
  68
  69 #define CMOV_ATOM QT_ATOM('c', 'm', 'o', 'v')
  70 #define STCO_ATOM QT_ATOM('s', 't', 'c', 'o')
  71 #define CO64_ATOM QT_ATOM('c', 'o', '6', '4')
  72
  73 #define ATOM_PREAMBLE_SIZE 8
  74 #define COPY_BUFFER_SIZE 1024
  75
  76 int main(int argc, char *argv[])
  77 {
  78     FILE *infile;
  79     FILE *outfile;
  80     unsigned char atom_bytes[ATOM_PREAMBLE_SIZE];
  81     uint32_t atom_type = 0;
  82     uint64_t atom_size = 0;
  83     uint64_t atom_offset = 0;
  84     uint64_t last_offset;
  85     unsigned char *moov_atom;
  86     unsigned char *ftyp_atom = 0;
  87     uint64_t moov_atom_size;
  88     uint64_t ftyp_atom_size = 0;
  89     uint64_t i, j;
  90     uint32_t offset_count;
  91     uint64_t current_offset;
  92     uint64_t start_offset = 0;
  93     unsigned char copy_buffer[COPY_BUFFER_SIZE];
  94     int bytes_to_copy;
  95
  96     if (argc != 3) {
  97         printf ("Usage: qt-faststart <infile.mov> <outfile.mov>\n");
  98         return 0;
  99     }
 100
 101     infile = fopen(argv[1], "rb");
 102     if (!infile) {
 103         perror(argv[1]);
 104         return 1;
 105     }
 106
 107     /* traverse through the atoms in the file to make sure that 'moov' is
 108      * at the end */
 109     while (!feof(infile)) {
 110         if (fread(atom_bytes, ATOM_PREAMBLE_SIZE, 1, infile) != 1) {
 111             break;
 112         }
 113         atom_size = (uint32_t)BE_32(&atom_bytes[0]);
 114         atom_type = BE_32(&atom_bytes[4]);
 115
 116         /* keep ftyp atom */
 117         if (atom_type == FTYP_ATOM) {
 118             ftyp_atom_size = atom_size;
 119             ftyp_atom = malloc(ftyp_atom_size);
 120             if (!ftyp_atom) {
 121                 printf ("could not allocate %"PRIu64" byte for ftyp atom\n",
 122                         atom_size);
 123                 fclose(infile);
 124                 return 1;
 125             }
 126             fseeko(infile, -ATOM_PREAMBLE_SIZE, SEEK_CUR);
 127             if (fread(ftyp_atom, atom_size, 1, infile) != 1) {
 128                 perror(argv[1]);
 129                 free(ftyp_atom);
 130                 fclose(infile);
 131                 return 1;
 132             }
 133             start_offset = ftello(infile);
 134         } else {
 135
 136         /* 64-bit special case */
 137         if (atom_size == 1) {
 138             if (fread(atom_bytes, ATOM_PREAMBLE_SIZE, 1, infile) != 1) {
 139                 break;
 140             }
 141             atom_size = BE_64(&atom_bytes[0]);
 142             fseeko(infile, atom_size - ATOM_PREAMBLE_SIZE * 2, SEEK_CUR);
 143         } else {
 144             fseeko(infile, atom_size - ATOM_PREAMBLE_SIZE, SEEK_CUR);
 145         }
 146     }
 147         printf("%c%c%c%c %10"PRIu64" %"PRIu64"\n",
 148                (atom_type >> 24) & 255,
 149                (atom_type >> 16) & 255,
 150                (atom_type >>  8) & 255,
 151                (atom_type >>  0) & 255,
 152                atom_offset,
 153                atom_size);
 154         if ((atom_type != FREE_ATOM) &&
 155             (atom_type != JUNK_ATOM) &&
 156             (atom_type != MDAT_ATOM) &&
 157             (atom_type != MOOV_ATOM) &&
 158             (atom_type != PNOT_ATOM) &&
 159             (atom_type != SKIP_ATOM) &&
 160             (atom_type != WIDE_ATOM) &&
 161             (atom_type != PICT_ATOM) &&
 162             (atom_type != UUID_ATOM) &&
 163             (atom_type != FTYP_ATOM)) {
 164             printf ("encountered non-QT top-level atom (is this a Quicktime file?)\n");
 165             break;
 166         }
 167         atom_offset += atom_size;
 168     }
 169
 170     if (atom_type != MOOV_ATOM) {
 171         printf ("last atom in file was not a moov atom\n");
 172         fclose(infile);
 173         return 0;
 174     }
 175
 176     /* moov atom was, in fact, the last atom in the chunk; load the whole
 177      * moov atom */
 178     fseeko(infile, -atom_size, SEEK_END);
 179     last_offset = ftello(infile);
 180     moov_atom_size = atom_size;
 181     moov_atom = malloc(moov_atom_size);
 182     if (!moov_atom) {
 183         printf ("could not allocate %"PRIu64" byte for moov atom\n",
 184             atom_size);
 185         fclose(infile);
 186         return 1;
 187     }
 188     if (fread(moov_atom, atom_size, 1, infile) != 1) {
 189         perror(argv[1]);
 190         free(moov_atom);
 191         fclose(infile);
 192         return 1;
 193     }
 194
 195     /* this utility does not support compressed atoms yet, so disqualify
 196      * files with compressed QT atoms */
 197     if (BE_32(&moov_atom[12]) == CMOV_ATOM) {
 198         printf ("this utility does not support compressed moov atoms yet\n");
 199         free(moov_atom);
 200         fclose(infile);
 201         return 1;
 202     }
 203
 204     /* close; will be re-opened later */
 205     fclose(infile);
 206
 207     /* crawl through the moov chunk in search of stco or co64 atoms */
 208     for (i = 4; i < moov_atom_size - 4; i++) {
 209         atom_type = BE_32(&moov_atom[i]);
 210         if (atom_type == STCO_ATOM) {
 211             printf (" patching stco atom...\n");
 212             atom_size = BE_32(&moov_atom[i - 4]);
 213             if (i + atom_size - 4 > moov_atom_size) {
 214                 printf (" bad atom size\n");
 215                 free(moov_atom);
 216                 return 1;
 217             }
 218             offset_count = BE_32(&moov_atom[i + 8]);
 219             for (j = 0; j < offset_count; j++) {
 220                 current_offset = BE_32(&moov_atom[i + 12 + j * 4]);
 221                 current_offset += moov_atom_size;
 222                 moov_atom[i + 12 + j * 4 + 0] = (current_offset >> 24) & 0xFF;
 223                 moov_atom[i + 12 + j * 4 + 1] = (current_offset >> 16) & 0xFF;
 224                 moov_atom[i + 12 + j * 4 + 2] = (current_offset >>  8) & 0xFF;
 225                 moov_atom[i + 12 + j * 4 + 3] = (current_offset >>  0) & 0xFF;
 226             }
 227             i += atom_size - 4;
 228         } else if (atom_type == CO64_ATOM) {
 229             printf (" patching co64 atom...\n");
 230             atom_size = BE_32(&moov_atom[i - 4]);
 231             if (i + atom_size - 4 > moov_atom_size) {
 232                 printf (" bad atom size\n");
 233                 free(moov_atom);
 234                 return 1;
 235             }
 236             offset_count = BE_32(&moov_atom[i + 8]);
 237             for (j = 0; j < offset_count; j++) {
 238                 current_offset = BE_64(&moov_atom[i + 12 + j * 8]);
 239                 current_offset += moov_atom_size;
 240                 moov_atom[i + 12 + j * 8 + 0] = (current_offset >> 56) & 0xFF;
 241                 moov_atom[i + 12 + j * 8 + 1] = (current_offset >> 48) & 0xFF;
 242                 moov_atom[i + 12 + j * 8 + 2] = (current_offset >> 40) & 0xFF;
 243                 moov_atom[i + 12 + j * 8 + 3] = (current_offset >> 32) & 0xFF;
 244                 moov_atom[i + 12 + j * 8 + 4] = (current_offset >> 24) & 0xFF;
 245                 moov_atom[i + 12 + j * 8 + 5] = (current_offset >> 16) & 0xFF;
 246                 moov_atom[i + 12 + j * 8 + 6] = (current_offset >>  8) & 0xFF;
 247                 moov_atom[i + 12 + j * 8 + 7] = (current_offset >>  0) & 0xFF;
 248             }
 249             i += atom_size - 4;
 250         }
 251     }
 252
 253     /* re-open the input file and open the output file */
 254     infile = fopen(argv[1], "rb");
 255     if (!infile) {
 256         perror(argv[1]);
 257         free(moov_atom);
 258         return 1;
 259     }
 260
 261     if (start_offset > 0) { /* seek after ftyp atom */
 262         fseeko(infile, start_offset, SEEK_SET);
 263         last_offset -= start_offset;
 264     }
 265
 266     outfile = fopen(argv[2], "wb");
 267     if (!outfile) {
 268         perror(argv[2]);
 269         fclose(outfile);
 270         free(moov_atom);
 271         return 1;
 272     }
 273
 274     /* dump the same ftyp atom */
 275     if (ftyp_atom_size > 0) {
 276         printf (" writing ftyp atom...\n");
 277         if (fwrite(ftyp_atom, ftyp_atom_size, 1, outfile) != 1) {
 278             perror(argv[2]);
 279             goto error_out;
 280         }
 281     }
 282
 283     /* dump the new moov atom */
 284     printf (" writing moov atom...\n");
 285     if (fwrite(moov_atom, moov_atom_size, 1, outfile) != 1) {
 286         perror(argv[2]);
 287         goto error_out;
 288     }
 289
 290     /* copy the remainder of the infile, from offset 0 -> last_offset - 1 */
 291     printf (" copying rest of file...\n");
 292     while (last_offset) {
 293         if (last_offset > COPY_BUFFER_SIZE)
 294             bytes_to_copy = COPY_BUFFER_SIZE;
 295         else
 296             bytes_to_copy = last_offset;
 297
 298         if (fread(copy_buffer, bytes_to_copy, 1, infile) != 1) {
 299             perror(argv[1]);
 300             goto error_out;
 301         }
 302         if (fwrite(copy_buffer, bytes_to_copy, 1, outfile) != 1) {
 303             perror(argv[2]);
 304             goto error_out;
 305         }
 306
 307         last_offset -= bytes_to_copy;
 308     }
 309
 310     fclose(infile);
 311     fclose(outfile);
 312     free(moov_atom);
 313     if (ftyp_atom_size > 0)
 314         free(ftyp_atom);
 315
 316     return 0;
 317
 318 error_out:
 319     fclose(infile);
 320     fclose(outfile);
 321     free(moov_atom);
 322     if (ftyp_atom_size > 0)
 323         free(ftyp_atom);
 324     return 1;
 325 }