summaryrefslogtreecommitdiff
path: root/tools/qt-faststart.c
blob: 79467f0415f70bd0533eedd99b893328791a366a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
/*
 * qt-faststart.c, v0.2
 * by Mike Melanson (melanson@pcisys.net)
 * This file is placed in the public domain. Use the program however you
 * see fit.
 *
 * This utility rearranges a Quicktime file such that the moov atom
 * is in front of the data, thus facilitating network streaming.
 *
 * To compile this program, start from the base directory from which you
 * are building FFmpeg and type:
 *  make tools/qt-faststart
 * The qt-faststart program will be built in the tools/ directory. If you
 * do not build the program in this manner, correct results are not
 * guaranteed, particularly on 64-bit platforms.
 * Invoke the program with:
 *  qt-faststart <infile.mov> <outfile.mov>
 *
 * Notes: Quicktime files can come in many configurations of top-level
 * atoms. This utility stipulates that the very last atom in the file needs
 * to be a moov atom. When given such a file, this utility will rearrange
 * the top-level atoms by shifting the moov atom from the back of the file
 * to the front, and patch the chunk offsets along the way. This utility
 * presently only operates on uncompressed moov atoms.
 */

#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <string.h>

#ifdef __MINGW32__
#define fseeko(x, y, z) fseeko64(x, y, z)
#define ftello(x)       ftello64(x)
#endif

#define BE_16(x) ((((uint8_t*)(x))[0] <<  8) | ((uint8_t*)(x))[1])

#define BE_32(x) ((((uint8_t*)(x))[0] << 24) |  \
                  (((uint8_t*)(x))[1] << 16) |  \
                  (((uint8_t*)(x))[2] <<  8) |  \
                   ((uint8_t*)(x))[3])

#define BE_64(x) (((uint64_t)(((uint8_t*)(x))[0]) << 56) |  \
                  ((uint64_t)(((uint8_t*)(x))[1]) << 48) |  \
                  ((uint64_t)(((uint8_t*)(x))[2]) << 40) |  \
                  ((uint64_t)(((uint8_t*)(x))[3]) << 32) |  \
                  ((uint64_t)(((uint8_t*)(x))[4]) << 24) |  \
                  ((uint64_t)(((uint8_t*)(x))[5]) << 16) |  \
                  ((uint64_t)(((uint8_t*)(x))[6]) <<  8) |  \
                  ((uint64_t)( (uint8_t*)(x))[7]))

#define BE_FOURCC(ch0, ch1, ch2, ch3)           \
    ( (uint32_t)(unsigned char)(ch3)        |   \
     ((uint32_t)(unsigned char)(ch2) <<  8) |   \
     ((uint32_t)(unsigned char)(ch1) << 16) |   \
     ((uint32_t)(unsigned char)(ch0) << 24) )

#define QT_ATOM BE_FOURCC
/* top level atoms */
#define FREE_ATOM QT_ATOM('f', 'r', 'e', 'e')
#define JUNK_ATOM QT_ATOM('j', 'u', 'n', 'k')
#define MDAT_ATOM QT_ATOM('m', 'd', 'a', 't')
#define MOOV_ATOM QT_ATOM('m', 'o', 'o', 'v')
#define PNOT_ATOM QT_ATOM('p', 'n', 'o', 't')
#define SKIP_ATOM QT_ATOM('s', 'k', 'i', 'p')
#define WIDE_ATOM QT_ATOM('w', 'i', 'd', 'e')
#define PICT_ATOM QT_ATOM('P', 'I', 'C', 'T')
#define FTYP_ATOM QT_ATOM('f', 't', 'y', 'p')
#define UUID_ATOM QT_ATOM('u', 'u', 'i', 'd')

#define CMOV_ATOM QT_ATOM('c', 'm', 'o', 'v')
#define STCO_ATOM QT_ATOM('s', 't', 'c', 'o')
#define CO64_ATOM QT_ATOM('c', 'o', '6', '4')

#define ATOM_PREAMBLE_SIZE    8
#define COPY_BUFFER_SIZE   1024

int main(int argc, char *argv[])
{
    FILE *infile  = NULL;
    FILE *outfile = NULL;
    unsigned char atom_bytes[ATOM_PREAMBLE_SIZE];
    uint32_t atom_type   = 0;
    uint64_t atom_size   = 0;
    uint64_t atom_offset = 0;
    uint64_t last_offset;
    unsigned char *moov_atom = NULL;
    unsigned char *ftyp_atom = NULL;
    uint64_t moov_atom_size;
    uint64_t ftyp_atom_size = 0;
    uint64_t i, j;
    uint32_t offset_count;
    uint64_t current_offset;
    uint64_t start_offset = 0;
    unsigned char copy_buffer[COPY_BUFFER_SIZE];
    int bytes_to_copy;

    if (argc != 3) {
        printf("Usage: qt-faststart <infile.mov> <outfile.mov>\n");
        return 0;
    }

    if (!strcmp(argv[1], argv[2])) {
        fprintf(stderr, "input and output files need to be different\n");
        return 1;
    }

    infile = fopen(argv[1], "rb");
    if (!infile) {
        perror(argv[1]);
        goto error_out;
    }

    /* traverse through the atoms in the file to make sure that 'moov' is
     * at the end */
    while (!feof(infile)) {
        if (fread(atom_bytes, ATOM_PREAMBLE_SIZE, 1, infile) != 1) {
            break;
        }
        atom_size = (uint32_t) BE_32(&atom_bytes[0]);
        atom_type = BE_32(&atom_bytes[4]);

        /* keep ftyp atom */
        if (atom_type == FTYP_ATOM) {
            ftyp_atom_size = atom_size;
            free(ftyp_atom);
            ftyp_atom = malloc(ftyp_atom_size);
            if (!ftyp_atom) {
                printf("could not allocate %"PRIu64" bytes for ftyp atom\n",
                       atom_size);
                goto error_out;
            }
            fseeko(infile, -ATOM_PREAMBLE_SIZE, SEEK_CUR);
            if (fread(ftyp_atom, atom_size, 1, infile) != 1) {
                perror(argv[1]);
                goto error_out;
            }
            start_offset = ftello(infile);
        } else {

            /* 64-bit special case */
            if (atom_size == 1) {
                if (fread(atom_bytes, ATOM_PREAMBLE_SIZE, 1, infile) != 1) {
                    break;
                }
                atom_size = BE_64(&atom_bytes[0]);
                fseeko(infile, atom_size - ATOM_PREAMBLE_SIZE * 2, SEEK_CUR);
            } else {
                fseeko(infile, atom_size - ATOM_PREAMBLE_SIZE, SEEK_CUR);
            }
        }
        printf("%c%c%c%c %10"PRIu64" %"PRIu64"\n",
               (atom_type >> 24) & 255,
               (atom_type >> 16) & 255,
               (atom_type >>  8) & 255,
               (atom_type >>  0) & 255,
               atom_offset,
               atom_size);
        if ((atom_type != FREE_ATOM) &&
            (atom_type != JUNK_ATOM) &&
            (atom_type != MDAT_ATOM) &&
            (atom_type != MOOV_ATOM) &&
            (atom_type != PNOT_ATOM) &&
            (atom_type != SKIP_ATOM) &&
            (atom_type != WIDE_ATOM) &&
            (atom_type != PICT_ATOM) &&
            (atom_type != UUID_ATOM) &&
            (atom_type != FTYP_ATOM)) {
            printf("encountered non-QT top-level atom (is this a QuickTime file?)\n");
            break;
        }
        atom_offset += atom_size;

        /* The atom header is 8 (or 16 bytes), if the atom size (which
         * includes these 8 or 16 bytes) is less than that, we won't be
         * able to continue scanning sensibly after this atom, so break. */
        if (atom_size < 8)
            break;
    }

    if (atom_type != MOOV_ATOM) {
        printf("last atom in file was not a moov atom\n");
        free(ftyp_atom);
        fclose(infile);
        return 0;
    }

    /* moov atom was, in fact, the last atom in the chunk; load the whole
     * moov atom */
    fseeko(infile, -atom_size, SEEK_END);
    last_offset    = ftello(infile);
    moov_atom_size = atom_size;
    moov_atom      = malloc(moov_atom_size);
    if (!moov_atom) {
        printf("could not allocate %"PRIu64" bytes for moov atom\n", atom_size);
        goto error_out;
    }
    if (fread(moov_atom, atom_size, 1, infile) != 1) {
        perror(argv[1]);
        goto error_out;
    }

    /* this utility does not support compressed atoms yet, so disqualify
     * files with compressed QT atoms */
    if (BE_32(&moov_atom[12]) == CMOV_ATOM) {
        printf("this utility does not support compressed moov atoms yet\n");
        goto error_out;
    }

    /* close; will be re-opened later */
    fclose(infile);
    infile = NULL;

    /* crawl through the moov chunk in search of stco or co64 atoms */
    for (i = 4; i < moov_atom_size - 4; i++) {
        atom_type = BE_32(&moov_atom[i]);
        if (atom_type == STCO_ATOM) {
            printf(" patching stco atom...\n");
            atom_size = BE_32(&moov_atom[i - 4]);
            if (i + atom_size - 4 > moov_atom_size) {
                printf(" bad atom size\n");
                goto error_out;
            }
            offset_count = BE_32(&moov_atom[i + 8]);
            for (j = 0; j < offset_count; j++) {
                current_offset  = BE_32(&moov_atom[i + 12 + j * 4]);
                current_offset += moov_atom_size;
                moov_atom[i + 12 + j * 4 + 0] = (current_offset >> 24) & 0xFF;
                moov_atom[i + 12 + j * 4 + 1] = (current_offset >> 16) & 0xFF;
                moov_atom[i + 12 + j * 4 + 2] = (current_offset >>  8) & 0xFF;
                moov_atom[i + 12 + j * 4 + 3] = (current_offset >>  0) & 0xFF;
            }
            i += atom_size - 4;
        } else if (atom_type == CO64_ATOM) {
            printf(" patching co64 atom...\n");
            atom_size = BE_32(&moov_atom[i - 4]);
            if (i + atom_size - 4 > moov_atom_size) {
                printf(" bad atom size\n");
                goto error_out;
            }
            offset_count = BE_32(&moov_atom[i + 8]);
            for (j = 0; j < offset_count; j++) {
                current_offset  = BE_64(&moov_atom[i + 12 + j * 8]);
                current_offset += moov_atom_size;
                moov_atom[i + 12 + j * 8 + 0] = (current_offset >> 56) & 0xFF;
                moov_atom[i + 12 + j * 8 + 1] = (current_offset >> 48) & 0xFF;
                moov_atom[i + 12 + j * 8 + 2] = (current_offset >> 40) & 0xFF;
                moov_atom[i + 12 + j * 8 + 3] = (current_offset >> 32) & 0xFF;
                moov_atom[i + 12 + j * 8 + 4] = (current_offset >> 24) & 0xFF;
                moov_atom[i + 12 + j * 8 + 5] = (current_offset >> 16) & 0xFF;
                moov_atom[i + 12 + j * 8 + 6] = (current_offset >>  8) & 0xFF;
                moov_atom[i + 12 + j * 8 + 7] = (current_offset >>  0) & 0xFF;
            }
            i += atom_size - 4;
        }
    }

    /* re-open the input file and open the output file */
    infile = fopen(argv[1], "rb");
    if (!infile) {
        perror(argv[1]);
        goto error_out;
    }

    if (start_offset > 0) { /* seek after ftyp atom */
        fseeko(infile, start_offset, SEEK_SET);
        last_offset -= start_offset;
    }

    outfile = fopen(argv[2], "wb");
    if (!outfile) {
        perror(argv[2]);
        goto error_out;
    }

    /* dump the same ftyp atom */
    if (ftyp_atom_size > 0) {
        printf(" writing ftyp atom...\n");
        if (fwrite(ftyp_atom, ftyp_atom_size, 1, outfile) != 1) {
            perror(argv[2]);
            goto error_out;
        }
    }

    /* dump the new moov atom */
    printf(" writing moov atom...\n");
    if (fwrite(moov_atom, moov_atom_size, 1, outfile) != 1) {
        perror(argv[2]);
        goto error_out;
    }

    /* copy the remainder of the infile, from offset 0 -> last_offset - 1 */
    printf(" copying rest of file...\n");
    while (last_offset) {
        if (last_offset > COPY_BUFFER_SIZE)
            bytes_to_copy = COPY_BUFFER_SIZE;
        else
            bytes_to_copy = last_offset;

        if (fread(copy_buffer, bytes_to_copy, 1, infile) != 1) {
            perror(argv[1]);
            goto error_out;
        }
        if (fwrite(copy_buffer, bytes_to_copy, 1, outfile) != 1) {
            perror(argv[2]);
            goto error_out;
        }
        last_offset -= bytes_to_copy;
    }

    fclose(infile);
    fclose(outfile);
    free(moov_atom);
    free(ftyp_atom);

    return 0;

error_out:
    if (infile)
        fclose(infile);
    if (outfile)
        fclose(outfile);
    free(moov_atom);
    free(ftyp_atom);
    return 1;
}