2 * Copyright (c) 2010 Bobby Bingham
4 * This file is part of FFmpeg.
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.
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.
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
23 * aspect ratio modification video filters
32 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
34 AspectContext *aspect = ctx->priv;
39 if (sscanf(args, "%d:%d", &aspect->aspect.num, &aspect->aspect.den) < 2) {
40 if (sscanf(args, "%lf", &ratio) < 1) {
41 av_log(ctx, AV_LOG_ERROR,
42 "Invalid string '%s' for aspect ratio.\n", args);
43 return AVERROR(EINVAL);
45 aspect->aspect = av_d2q(ratio, 100);
47 gcd = av_gcd(FFABS(aspect->aspect.num), FFABS(aspect->aspect.den));
49 aspect->aspect.num /= gcd;
50 aspect->aspect.den /= gcd;
55 if (aspect->aspect.den == 0)
56 aspect->aspect = (AVRational) {0, 1};
58 av_log(ctx, AV_LOG_INFO, "a:%d/%d\n", aspect->aspect.num, aspect->aspect.den);
62 static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
64 AspectContext *aspect = link->dst->priv;
66 picref->video->pixel_aspect = aspect->aspect;
67 avfilter_start_frame(link->dst->outputs[0], picref);
70 #if CONFIG_SETDAR_FILTER
71 /* for setdar filter, convert from frame aspect ratio to pixel aspect ratio */
72 static int setdar_config_props(AVFilterLink *inlink)
74 AspectContext *aspect = inlink->dst->priv;
75 AVRational dar = aspect->aspect;
77 av_reduce(&aspect->aspect.num, &aspect->aspect.den,
78 aspect->aspect.num * inlink->h,
79 aspect->aspect.den * inlink->w, 100);
81 av_log(inlink->dst, AV_LOG_INFO, "w:%d h:%d -> dar:%d/%d par:%d/%d\n",
82 inlink->h, inlink->w, dar.num, dar.den, aspect->aspect.num, aspect->aspect.den);
86 AVFilter avfilter_vf_setdar = {
88 .description = NULL_IF_CONFIG_SMALL("Set the frame display aspect ratio."),
92 .priv_size = sizeof(AspectContext),
94 .inputs = (AVFilterPad[]) {{ .name = "default",
95 .type = AVMEDIA_TYPE_VIDEO,
96 .config_props = setdar_config_props,
97 .get_video_buffer = avfilter_null_get_video_buffer,
98 .start_frame = start_frame,
99 .end_frame = avfilter_null_end_frame },
102 .outputs = (AVFilterPad[]) {{ .name = "default",
103 .type = AVMEDIA_TYPE_VIDEO, },
106 #endif /* CONFIG_SETDAR_FILTER */
108 #if CONFIG_SETSAR_FILTER
109 AVFilter avfilter_vf_setsar = {
111 .description = NULL_IF_CONFIG_SMALL("Set the pixel sample aspect ratio."),
115 .priv_size = sizeof(AspectContext),
117 .inputs = (AVFilterPad[]) {{ .name = "default",
118 .type = AVMEDIA_TYPE_VIDEO,
119 .get_video_buffer = avfilter_null_get_video_buffer,
120 .start_frame = start_frame,
121 .end_frame = avfilter_null_end_frame },
124 .outputs = (AVFilterPad[]) {{ .name = "default",
125 .type = AVMEDIA_TYPE_VIDEO, },
128 #endif /* CONFIG_SETSAR_FILTER */