3 * by Mike Melanson (melanson@pcisys.net)
4 * This file is placed in the public domain. Use the program however you
7 * This utility rearranges a Quicktime file such that the moov atom
8 * is in front of the data, thus facilitating network streaming.
10 * Compile this program using:
11 * cc qt-faststart.c -o qt-faststart
12 * Invoke the program with:
13 * qt-faststart <infile.mov> <outfile.mov>
15 * Notes: Quicktime files can come in many configurations of top-level
16 * atoms. This utility stipulates that the very last atom in the file needs
17 * to be a moov atom. When given such a file, this utility will rearrange
18 * the top-level atoms by shifting the moov atom from the back of the file
19 * to the front, and patch the chunk offsets along the way. This utility
20 * presently only operates on uncompressed moov atoms.
27 #define BE_16(x) ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
28 #define BE_32(x) ((((uint8_t*)(x))[0] << 24) | \
29 (((uint8_t*)(x))[1] << 16) | \
30 (((uint8_t*)(x))[2] << 8) | \
32 #define BE_64(x) (((uint64_t)(((uint8_t*)(x))[0]) << 56) | \
33 ((uint64_t)(((uint8_t*)(x))[1]) << 48) | \
34 ((uint64_t)(((uint8_t*)(x))[2]) << 40) | \
35 ((uint64_t)(((uint8_t*)(x))[3]) << 32) | \
36 ((uint64_t)(((uint8_t*)(x))[4]) << 24) | \
37 ((uint64_t)(((uint8_t*)(x))[5]) << 16) | \
38 ((uint64_t)(((uint8_t*)(x))[6]) << 8) | \
39 ((uint64_t)((uint8_t*)(x))[7]))
41 #define BE_FOURCC( ch0, ch1, ch2, ch3 ) \
42 ( (uint32_t)(unsigned char)(ch3) | \
43 ( (uint32_t)(unsigned char)(ch2) << 8 ) | \
44 ( (uint32_t)(unsigned char)(ch1) << 16 ) | \
45 ( (uint32_t)(unsigned char)(ch0) << 24 ) )
47 #define QT_ATOM BE_FOURCC
49 #define FREE_ATOM QT_ATOM('f', 'r', 'e', 'e')
50 #define JUNK_ATOM QT_ATOM('j', 'u', 'n', 'k')
51 #define MDAT_ATOM QT_ATOM('m', 'd', 'a', 't')
52 #define MOOV_ATOM QT_ATOM('m', 'o', 'o', 'v')
53 #define PNOT_ATOM QT_ATOM('p', 'n', 'o', 't')
54 #define SKIP_ATOM QT_ATOM('s', 'k', 'i', 'p')
55 #define WIDE_ATOM QT_ATOM('w', 'i', 'd', 'e')
56 #define PICT_ATOM QT_ATOM('P', 'I', 'C', 'T')
57 #define FTYP_ATOM QT_ATOM('f', 't', 'y', 'p')
59 #define CMOV_ATOM QT_ATOM('c', 'm', 'o', 'v')
60 #define STCO_ATOM QT_ATOM('s', 't', 'c', 'o')
61 #define CO64_ATOM QT_ATOM('c', 'o', '6', '4')
63 #define ATOM_PREAMBLE_SIZE 8
64 #define COPY_BUFFER_SIZE 1024
66 int main(int argc
, char *argv
[])
70 unsigned char atom_bytes
[ATOM_PREAMBLE_SIZE
];
71 uint32_t atom_type
= 0;
74 unsigned char *moov_atom
;
75 uint64_t moov_atom_size
;
77 uint32_t offset_count
;
78 uint64_t current_offset
;
79 unsigned char copy_buffer
[COPY_BUFFER_SIZE
];
83 printf ("Usage: qt-faststart <infile.mov> <outfile.mov>\n");
87 infile
= fopen(argv
[1], "rb");
93 /* traverse through the atoms in the file to make sure that 'moov' is
95 while (!feof(infile
)) {
96 if (fread(atom_bytes
, ATOM_PREAMBLE_SIZE
, 1, infile
) != 1) {
99 atom_size
= BE_32(&atom_bytes
[0]);
100 atom_type
= BE_32(&atom_bytes
[4]);
102 if ((atom_type
!= FREE_ATOM
) &&
103 (atom_type
!= JUNK_ATOM
) &&
104 (atom_type
!= MDAT_ATOM
) &&
105 (atom_type
!= MOOV_ATOM
) &&
106 (atom_type
!= PNOT_ATOM
) &&
107 (atom_type
!= SKIP_ATOM
) &&
108 (atom_type
!= WIDE_ATOM
) &&
109 (atom_type
!= PICT_ATOM
) &&
110 (atom_type
!= FTYP_ATOM
)) {
111 printf ("encountered non-QT top-level atom (is this a Quicktime file?)\n");
115 /* 64-bit special case */
116 if (atom_size
== 1) {
117 if (fread(atom_bytes
, ATOM_PREAMBLE_SIZE
, 1, infile
) != 1) {
120 atom_size
= BE_64(&atom_bytes
[0]);
121 fseek(infile
, atom_size
- ATOM_PREAMBLE_SIZE
* 2, SEEK_CUR
);
123 fseek(infile
, atom_size
- ATOM_PREAMBLE_SIZE
, SEEK_CUR
);
127 if (atom_type
!= MOOV_ATOM
) {
128 printf ("last atom in file was not a moov atom\n");
133 /* moov atom was, in fact, the last atom in the chunk; load the whole
135 fseek(infile
, -atom_size
, SEEK_END
);
136 last_offset
= (uint64_t)ftell(infile
);
137 moov_atom_size
= atom_size
;
138 moov_atom
= malloc(moov_atom_size
);
140 printf ("could not allocate 0x%llX byte for moov atom\n",
145 if (fread(moov_atom
, atom_size
, 1, infile
) != 1) {
152 /* this utility does not support compressed atoms yet, so disqualify
153 * files with compressed QT atoms */
154 if (BE_32(&moov_atom
[12]) == CMOV_ATOM
) {
155 printf ("this utility does not support compressed moov atoms yet\n");
161 /* close; will be re-opened later */
164 /* crawl through the moov chunk in search of stco or co64 atoms */
165 for (i
= 4; i
< moov_atom_size
- 4; i
++) {
166 atom_type
= BE_32(&moov_atom
[i
]);
167 if (atom_type
== STCO_ATOM
) {
168 printf (" patching stco atom...\n");
169 atom_size
= BE_32(&moov_atom
[i
- 4]);
170 if (i
+ atom_size
- 4 > moov_atom_size
) {
171 printf (" bad atom size\n");
175 offset_count
= BE_32(&moov_atom
[i
+ 8]);
176 for (j
= 0; j
< offset_count
; j
++) {
177 current_offset
= BE_32(&moov_atom
[i
+ 12 + j
* 4]);
178 current_offset
+= moov_atom_size
;
179 moov_atom
[i
+ 12 + j
* 4 + 0] = (current_offset
>> 24) & 0xFF;
180 moov_atom
[i
+ 12 + j
* 4 + 1] = (current_offset
>> 16) & 0xFF;
181 moov_atom
[i
+ 12 + j
* 4 + 2] = (current_offset
>> 8) & 0xFF;
182 moov_atom
[i
+ 12 + j
* 4 + 3] = (current_offset
>> 0) & 0xFF;
185 } else if (atom_type
== CO64_ATOM
) {
186 printf (" patching co64 atom...\n");
187 atom_size
= BE_32(&moov_atom
[i
- 4]);
188 if (i
+ atom_size
- 4 > moov_atom_size
) {
189 printf (" bad atom size\n");
193 offset_count
= BE_32(&moov_atom
[i
+ 8]);
194 for (j
= 0; j
< offset_count
; j
++) {
195 current_offset
= BE_64(&moov_atom
[i
+ 12 + j
* 8]);
196 current_offset
+= moov_atom_size
;
197 moov_atom
[i
+ 12 + j
* 8 + 0] = (current_offset
>> 56) & 0xFF;
198 moov_atom
[i
+ 12 + j
* 8 + 1] = (current_offset
>> 48) & 0xFF;
199 moov_atom
[i
+ 12 + j
* 8 + 2] = (current_offset
>> 40) & 0xFF;
200 moov_atom
[i
+ 12 + j
* 8 + 3] = (current_offset
>> 32) & 0xFF;
201 moov_atom
[i
+ 12 + j
* 8 + 4] = (current_offset
>> 24) & 0xFF;
202 moov_atom
[i
+ 12 + j
* 8 + 5] = (current_offset
>> 16) & 0xFF;
203 moov_atom
[i
+ 12 + j
* 8 + 6] = (current_offset
>> 8) & 0xFF;
204 moov_atom
[i
+ 12 + j
* 8 + 7] = (current_offset
>> 0) & 0xFF;
210 /* re-open the input file and open the output file */
211 infile
= fopen(argv
[1], "rb");
217 outfile
= fopen(argv
[2], "wb");
225 /* dump the new moov atom */
226 printf (" writing moov atom...\n");
227 if (fwrite(moov_atom
, moov_atom_size
, 1, outfile
) != 1) {
232 /* copy the remainder of the infile, from offset 0 -> last_offset - 1 */
233 printf (" copying rest of file...\n");
234 while (last_offset
) {
235 if (last_offset
> COPY_BUFFER_SIZE
)
236 bytes_to_copy
= COPY_BUFFER_SIZE
;
238 bytes_to_copy
= last_offset
;
240 if (fread(copy_buffer
, bytes_to_copy
, 1, infile
) != 1) {
244 if (fwrite(copy_buffer
, bytes_to_copy
, 1, outfile
) != 1) {
249 last_offset
-= bytes_to_copy
;