2 * This file is part of FFmpeg.
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 #ifndef AVFILTER_SCALE_EVAL_H
20 #define AVFILTER_SCALE_EVAL_H
25 * Parse and evaluate string expressions for width and height. Upon success,
26 * ff_scale_adjust_dimensions must be called with evaluated width and height
27 * to obtain actual target dimensions.
29 * Returns 0 upon success, negative value if one of the expressions could
30 * not be parsed or if NaN was the result of their evaluation.
32 int ff_scale_eval_dimensions(void *ctx,
33 const char *w_expr, const char *h_expr,
34 AVFilterLink *inlink, AVFilterLink *outlink,
35 int *ret_w, int *ret_h);
38 * Transform evaluated width and height obtained from ff_scale_eval_dimensions
39 * into actual target width and height for scaling. Adjustment can occur if one
40 * or both of the evaluated values are of the form '-n' or if
41 * force_original_aspect_ratio is set.
45 int ff_scale_adjust_dimensions(AVFilterLink *inlink,
46 int *ret_w, int *ret_h,
47 int force_original_aspect_ratio, int force_divisible_by);