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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  .get_video_buffer = ff_null_get_video_buffer,
147  .filter_frame = filter_frame,
148  },
149  { NULL }
150 };
151 
152 static const AVFilterPad avfilter_vf_setdar_outputs[] = {
153  {
154  .name = "default",
155  .type = AVMEDIA_TYPE_VIDEO,
156  },
157  { NULL }
158 };
159 
160 AVFilter avfilter_vf_setdar = {
161  .name = "setdar",
162  .description = NULL_IF_CONFIG_SMALL("Set the frame display aspect ratio."),
163  .init = init,
164  .priv_size = sizeof(AspectContext),
165  .priv_class = &setdar_class,
166 
167  .inputs = avfilter_vf_setdar_inputs,
168 
169  .outputs = avfilter_vf_setdar_outputs,
170 };
171 
172 #endif /* CONFIG_SETDAR_FILTER */
173 
174 #if CONFIG_SETSAR_FILTER
175 
176 static int setsar_config_props(AVFilterLink *inlink)
177 {
178  AspectContext *s = inlink->dst->priv;
179  AVRational old_sar = inlink->sample_aspect_ratio;
180  AVRational old_dar, dar;
181 
182  inlink->sample_aspect_ratio = s->sar;
183 
184  compute_dar(&old_dar, old_sar, inlink->w, inlink->h);
185  compute_dar(&dar, s->sar, inlink->w, inlink->h);
186  av_log(inlink->dst, AV_LOG_VERBOSE, "w:%d h:%d sar:%d/%d dar:%d/%d -> sar:%d/%d dar:%d/%d\n",
187  inlink->w, inlink->h, old_sar.num, old_sar.den, old_dar.num, old_dar.den,
188  inlink->sample_aspect_ratio.num, inlink->sample_aspect_ratio.den, dar.num, dar.den);
189 
190  return 0;
191 }
192 
193 static const AVOption setsar_options[] = {
194  { "sar", "set sample (pixel) aspect ratio", OFFSET(ratio_str), AV_OPT_TYPE_STRING, {.str="0"}, .flags=FLAGS },
195  { "ratio", "set sample (pixel) aspect ratio", OFFSET(ratio_str), AV_OPT_TYPE_STRING, {.str="0"}, .flags=FLAGS },
196  { "r", "set sample (pixel) aspect ratio", OFFSET(ratio_str), AV_OPT_TYPE_STRING, {.str="0"}, .flags=FLAGS },
197 #if FF_API_OLD_FILTER_OPTS
198  { "sar_den", NULL, OFFSET(aspect_den), AV_OPT_TYPE_FLOAT, { .dbl = 0 }, 0, FLT_MAX, FLAGS },
199 #endif
200  { "max", "set max value for nominator or denominator in the ratio", OFFSET(max), AV_OPT_TYPE_INT, {.i64=100}, 1, INT_MAX, FLAGS },
201  { NULL }
202 };
203 
204 AVFILTER_DEFINE_CLASS(setsar);
205 
206 static const AVFilterPad avfilter_vf_setsar_inputs[] = {
207  {
208  .name = "default",
209  .type = AVMEDIA_TYPE_VIDEO,
210  .config_props = setsar_config_props,
211  .get_video_buffer = ff_null_get_video_buffer,
212  .filter_frame = filter_frame,
213  },
214  { NULL }
215 };
216 
217 static const AVFilterPad avfilter_vf_setsar_outputs[] = {
218  {
219  .name = "default",
220  .type = AVMEDIA_TYPE_VIDEO,
221  },
222  { NULL }
223 };
224 
225 AVFilter avfilter_vf_setsar = {
226  .name = "setsar",
227  .description = NULL_IF_CONFIG_SMALL("Set the pixel sample aspect ratio."),
228  .init = init,
229  .priv_size = sizeof(AspectContext),
230  .priv_class = &setsar_class,
231 
232  .inputs = avfilter_vf_setsar_inputs,
233 
234  .outputs = avfilter_vf_setsar_outputs,
235 };
236 
237 #endif /* CONFIG_SETSAR_FILTER */