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vf_aspect.c
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1 /*
2  * Copyright (c) 2010 Bobby Bingham
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 /**
22  * @file
23  * aspect ratio modification video filters
24  */
25 
26 #include <float.h>
27 
28 #include "libavutil/common.h"
29 #include "libavutil/eval.h"
30 #include "libavutil/mathematics.h"
31 #include "libavutil/opt.h"
32 #include "libavutil/parseutils.h"
33 
34 #include "avfilter.h"
35 #include "internal.h"
36 #include "video.h"
37 
38 typedef struct {
39  const AVClass *class;
42  int max;
43 #if FF_API_OLD_FILTER_OPTS
44  float aspect_den;
45 #endif
46  char *ratio_str;
48 
49 static av_cold int init(AVFilterContext *ctx)
50 {
51  AspectContext *s = ctx->priv;
52  int ret;
53 
54 #if FF_API_OLD_FILTER_OPTS
55  if (s->ratio_str && s->aspect_den > 0) {
56  double num;
58  "num:den syntax is deprecated, please use num/den or named options instead\n");
59  ret = av_expr_parse_and_eval(&num, s->ratio_str, NULL, NULL,
60  NULL, NULL, NULL, NULL, NULL, 0, ctx);
61  if (ret < 0) {
62  av_log(ctx, AV_LOG_ERROR, "Unable to parse ratio numerator \"%s\"\n", s->ratio_str);
63  return AVERROR(EINVAL);
64  }
65  s->sar = s->dar = av_d2q(num / s->aspect_den, s->max);
66  } else
67 #endif
68  if (s->ratio_str) {
69  ret = av_parse_ratio(&s->sar, s->ratio_str, s->max, 0, ctx);
70  if (ret < 0 || s->sar.num < 0 || s->sar.den <= 0) {
71  av_log(ctx, AV_LOG_ERROR,
72  "Invalid string '%s' for aspect ratio\n", s->ratio_str);
73  return AVERROR(EINVAL);
74  }
75  s->dar = s->sar;
76  }
77  return 0;
78 }
79 
81 {
82  AspectContext *s = link->dst->priv;
83 
84  frame->sample_aspect_ratio = s->sar;
85  return ff_filter_frame(link->dst->outputs[0], frame);
86 }
87 
88 #define OFFSET(x) offsetof(AspectContext, x)
89 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
90 
91 static inline void compute_dar(AVRational *dar, AVRational sar, int w, int h)
92 {
93  if (sar.num && sar.den) {
94  av_reduce(&dar->num, &dar->den, sar.num * w, sar.den * h, INT_MAX);
95  } else {
96  av_reduce(&dar->num, &dar->den, w, h, INT_MAX);
97  }
98 }
99 
100 #if CONFIG_SETDAR_FILTER
101 
102 static int setdar_config_props(AVFilterLink *inlink)
103 {
104  AspectContext *s = inlink->dst->priv;
105  AVRational dar;
106  AVRational old_dar;
107  AVRational old_sar = inlink->sample_aspect_ratio;
108 
109  if (s->dar.num && s->dar.den) {
110  av_reduce(&s->sar.num, &s->sar.den,
111  s->dar.num * inlink->h,
112  s->dar.den * inlink->w, INT_MAX);
113  inlink->sample_aspect_ratio = s->sar;
114  dar = s->dar;
115  } else {
116  inlink->sample_aspect_ratio = (AVRational){ 1, 1 };
117  dar = (AVRational){ inlink->w, inlink->h };
118  }
119 
120  compute_dar(&old_dar, old_sar, inlink->w, inlink->h);
121  av_log(inlink->dst, AV_LOG_VERBOSE, "w:%d h:%d dar:%d/%d sar:%d/%d -> dar:%d/%d sar:%d/%d\n",
122  inlink->w, inlink->h, old_dar.num, old_dar.den, old_sar.num, old_sar.den,
123  dar.num, dar.den, inlink->sample_aspect_ratio.num, inlink->sample_aspect_ratio.den);
124 
125  return 0;
126 }
127 
128 static const AVOption setdar_options[] = {
129  { "dar", "set display aspect ratio", OFFSET(ratio_str), AV_OPT_TYPE_STRING, {.str="0"}, .flags=FLAGS },
130  { "ratio", "set display aspect ratio", OFFSET(ratio_str), AV_OPT_TYPE_STRING, {.str="0"}, .flags=FLAGS },
131  { "r", "set display aspect ratio", OFFSET(ratio_str), AV_OPT_TYPE_STRING, {.str="0"}, .flags=FLAGS },
132 #if FF_API_OLD_FILTER_OPTS
133  { "dar_den", NULL, OFFSET(aspect_den), AV_OPT_TYPE_FLOAT, { .dbl = 0 }, 0, FLT_MAX, FLAGS },
134 #endif
135  { "max", "set max value for nominator or denominator in the ratio", OFFSET(max), AV_OPT_TYPE_INT, {.i64=100}, 1, INT_MAX, FLAGS },
136  { NULL }
137 };
138 
139 AVFILTER_DEFINE_CLASS(setdar);
140 
141 static const AVFilterPad avfilter_vf_setdar_inputs[] = {
142  {
143  .name = "default",
144  .type = AVMEDIA_TYPE_VIDEO,
145  .config_props = setdar_config_props,
146  .filter_frame = filter_frame,
147  },
148  { NULL }
149 };
150 
151 static const AVFilterPad avfilter_vf_setdar_outputs[] = {
152  {
153  .name = "default",
154  .type = AVMEDIA_TYPE_VIDEO,
155  },
156  { NULL }
157 };
158 
159 AVFilter avfilter_vf_setdar = {
160  .name = "setdar",
161  .description = NULL_IF_CONFIG_SMALL("Set the frame display aspect ratio."),
162  .init = init,
163  .priv_size = sizeof(AspectContext),
164  .priv_class = &setdar_class,
165  .inputs = avfilter_vf_setdar_inputs,
166  .outputs = avfilter_vf_setdar_outputs,
167 };
168 
169 #endif /* CONFIG_SETDAR_FILTER */
170 
171 #if CONFIG_SETSAR_FILTER
172 
173 static int setsar_config_props(AVFilterLink *inlink)
174 {
175  AspectContext *s = inlink->dst->priv;
176  AVRational old_sar = inlink->sample_aspect_ratio;
177  AVRational old_dar, dar;
178 
179  inlink->sample_aspect_ratio = s->sar;
180 
181  compute_dar(&old_dar, old_sar, inlink->w, inlink->h);
182  compute_dar(&dar, s->sar, inlink->w, inlink->h);
183  av_log(inlink->dst, AV_LOG_VERBOSE, "w:%d h:%d sar:%d/%d dar:%d/%d -> sar:%d/%d dar:%d/%d\n",
184  inlink->w, inlink->h, old_sar.num, old_sar.den, old_dar.num, old_dar.den,
185  inlink->sample_aspect_ratio.num, inlink->sample_aspect_ratio.den, dar.num, dar.den);
186 
187  return 0;
188 }
189 
190 static const AVOption setsar_options[] = {
191  { "sar", "set sample (pixel) aspect ratio", OFFSET(ratio_str), AV_OPT_TYPE_STRING, {.str="0"}, .flags=FLAGS },
192  { "ratio", "set sample (pixel) aspect ratio", OFFSET(ratio_str), AV_OPT_TYPE_STRING, {.str="0"}, .flags=FLAGS },
193  { "r", "set sample (pixel) aspect ratio", OFFSET(ratio_str), AV_OPT_TYPE_STRING, {.str="0"}, .flags=FLAGS },
194 #if FF_API_OLD_FILTER_OPTS
195  { "sar_den", NULL, OFFSET(aspect_den), AV_OPT_TYPE_FLOAT, { .dbl = 0 }, 0, FLT_MAX, FLAGS },
196 #endif
197  { "max", "set max value for nominator or denominator in the ratio", OFFSET(max), AV_OPT_TYPE_INT, {.i64=100}, 1, INT_MAX, FLAGS },
198  { NULL }
199 };
200 
201 AVFILTER_DEFINE_CLASS(setsar);
202 
203 static const AVFilterPad avfilter_vf_setsar_inputs[] = {
204  {
205  .name = "default",
206  .type = AVMEDIA_TYPE_VIDEO,
207  .config_props = setsar_config_props,
208  .filter_frame = filter_frame,
209  },
210  { NULL }
211 };
212 
213 static const AVFilterPad avfilter_vf_setsar_outputs[] = {
214  {
215  .name = "default",
216  .type = AVMEDIA_TYPE_VIDEO,
217  },
218  { NULL }
219 };
220 
221 AVFilter avfilter_vf_setsar = {
222  .name = "setsar",
223  .description = NULL_IF_CONFIG_SMALL("Set the pixel sample aspect ratio."),
224  .init = init,
225  .priv_size = sizeof(AspectContext),
226  .priv_class = &setsar_class,
227  .inputs = avfilter_vf_setsar_inputs,
228  .outputs = avfilter_vf_setsar_outputs,
229 };
230 
231 #endif /* CONFIG_SETSAR_FILTER */