1 /*
2 * Mpeg video formats-related defines and utility functions
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #include <stdint.h>
22
26
29
32 int y,
int h,
int picture_structure,
34 {
37 const int field_pic = picture_structure !=
PICT_FRAME;
38 if (field_pic) {
39 h <<= 1;
40 y <<= 1;
41 }
42
44
45 if (field_pic && first_field &&
47 return;
48
52 int i;
53
56 src = cur;
57 else if (last)
58 src = last;
59 else
60 return;
61
66 offset[i] = 0;
67 } else {
69 offset[1]=
70 offset[2]= (y >> vshift) * src->
linesize[1];
72 offset[i] = 0;
73 }
74
75 emms_c();
76
78 y, picture_structure, h);
79 }
80 }