lavfi: add error handling to start_frame().
[libav.git] / libavfilter / vf_aspect.c
1 /*
2 * Copyright (c) 2010 Bobby Bingham
3
4 * This file is part of Libav.
5 *
6 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 /**
22 * @file
23 * aspect ratio modification video filters
24 */
25
26 #include "libavutil/mathematics.h"
27 #include "avfilter.h"
28 #include "internal.h"
29 #include "video.h"
30
31 typedef struct {
32 AVRational aspect;
33 } AspectContext;
34
35 static av_cold int init(AVFilterContext *ctx, const char *args)
36 {
37 AspectContext *aspect = ctx->priv;
38 double ratio;
39 int64_t gcd;
40 char c = 0;
41
42 if (args) {
43 if (sscanf(args, "%d:%d%c", &aspect->aspect.num, &aspect->aspect.den, &c) != 2)
44 if (sscanf(args, "%lf%c", &ratio, &c) == 1)
45 aspect->aspect = av_d2q(ratio, 100);
46
47 if (c || aspect->aspect.num <= 0 || aspect->aspect.den <= 0) {
48 av_log(ctx, AV_LOG_ERROR,
49 "Invalid string '%s' for aspect ratio.\n", args);
50 return AVERROR(EINVAL);
51 }
52
53 gcd = av_gcd(FFABS(aspect->aspect.num), FFABS(aspect->aspect.den));
54 if (gcd) {
55 aspect->aspect.num /= gcd;
56 aspect->aspect.den /= gcd;
57 }
58 }
59
60 if (aspect->aspect.den == 0)
61 aspect->aspect = (AVRational) {0, 1};
62
63 av_log(ctx, AV_LOG_VERBOSE, "a:%d/%d\n", aspect->aspect.num, aspect->aspect.den);
64 return 0;
65 }
66
67 static int start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
68 {
69 AspectContext *aspect = link->dst->priv;
70
71 picref->video->pixel_aspect = aspect->aspect;
72 link->cur_buf = NULL;
73 return ff_start_frame(link->dst->outputs[0], picref);
74 }
75
76 #if CONFIG_SETDAR_FILTER
77 /* for setdar filter, convert from frame aspect ratio to pixel aspect ratio */
78 static int setdar_config_props(AVFilterLink *inlink)
79 {
80 AspectContext *aspect = inlink->dst->priv;
81 AVRational dar = aspect->aspect;
82
83 av_reduce(&aspect->aspect.num, &aspect->aspect.den,
84 aspect->aspect.num * inlink->h,
85 aspect->aspect.den * inlink->w, 100);
86
87 av_log(inlink->dst, AV_LOG_VERBOSE, "w:%d h:%d -> dar:%d/%d sar:%d/%d\n",
88 inlink->w, inlink->h, dar.num, dar.den, aspect->aspect.num, aspect->aspect.den);
89
90 inlink->sample_aspect_ratio = aspect->aspect;
91
92 return 0;
93 }
94
95 AVFilter avfilter_vf_setdar = {
96 .name = "setdar",
97 .description = NULL_IF_CONFIG_SMALL("Set the frame display aspect ratio."),
98
99 .init = init,
100
101 .priv_size = sizeof(AspectContext),
102
103 .inputs = (const AVFilterPad[]) {{ .name = "default",
104 .type = AVMEDIA_TYPE_VIDEO,
105 .config_props = setdar_config_props,
106 .get_video_buffer = ff_null_get_video_buffer,
107 .start_frame = start_frame,
108 .end_frame = ff_null_end_frame },
109 { .name = NULL}},
110
111 .outputs = (const AVFilterPad[]) {{ .name = "default",
112 .type = AVMEDIA_TYPE_VIDEO, },
113 { .name = NULL}},
114 };
115 #endif /* CONFIG_SETDAR_FILTER */
116
117 #if CONFIG_SETSAR_FILTER
118 /* for setdar filter, convert from frame aspect ratio to pixel aspect ratio */
119 static int setsar_config_props(AVFilterLink *inlink)
120 {
121 AspectContext *aspect = inlink->dst->priv;
122
123 inlink->sample_aspect_ratio = aspect->aspect;
124
125 return 0;
126 }
127
128 AVFilter avfilter_vf_setsar = {
129 .name = "setsar",
130 .description = NULL_IF_CONFIG_SMALL("Set the pixel sample aspect ratio."),
131
132 .init = init,
133
134 .priv_size = sizeof(AspectContext),
135
136 .inputs = (const AVFilterPad[]) {{ .name = "default",
137 .type = AVMEDIA_TYPE_VIDEO,
138 .config_props = setsar_config_props,
139 .get_video_buffer = ff_null_get_video_buffer,
140 .start_frame = start_frame,
141 .end_frame = ff_null_end_frame },
142 { .name = NULL}},
143
144 .outputs = (const AVFilterPad[]) {{ .name = "default",
145 .type = AVMEDIA_TYPE_VIDEO, },
146 { .name = NULL}},
147 };
148 #endif /* CONFIG_SETSAR_FILTER */