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vf_drawbox.c
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1 /*
2  * Copyright (c) 2008 Affine Systems, Inc (Michael Sullivan, Bobby Impollonia)
3  * Copyright (c) 2013 Andrey Utkin <andrey.krieger.utkin gmail com>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Box and grid drawing filters. Also a nice template for a filter
25  * that needs to write in the input frame.
26  */
27 
28 #include "libavutil/colorspace.h"
29 #include "libavutil/common.h"
30 #include "libavutil/opt.h"
31 #include "libavutil/eval.h"
32 #include "libavutil/pixdesc.h"
33 #include "libavutil/parseutils.h"
34 #include "avfilter.h"
35 #include "formats.h"
36 #include "internal.h"
37 #include "video.h"
38 
39 static const char *const var_names[] = {
40  "dar",
41  "hsub", "vsub",
42  "in_h", "ih", ///< height of the input video
43  "in_w", "iw", ///< width of the input video
44  "sar",
45  "x",
46  "y",
47  "h", ///< height of the rendered box
48  "w", ///< width of the rendered box
49  "t",
50  NULL
51 };
52 
53 enum { Y, U, V, A };
54 
55 enum var_name {
67 };
68 
69 typedef struct {
70  const AVClass *class;
71  int x, y, w, h;
72  int thickness;
73  char *color_str;
74  unsigned char yuv_color[4];
75  int invert_color; ///< invert luma color
76  int vsub, hsub; ///< chroma subsampling
77  char *x_expr, *y_expr; ///< expression for x and y
78  char *w_expr, *h_expr; ///< expression for width and height
79  char *t_expr; ///< expression for thickness
81 
82 static const int NUM_EXPR_EVALS = 5;
83 
84 static av_cold int init(AVFilterContext *ctx)
85 {
86  DrawBoxContext *s = ctx->priv;
87  uint8_t rgba_color[4];
88 
89  if (!strcmp(s->color_str, "invert"))
90  s->invert_color = 1;
91  else if (av_parse_color(rgba_color, s->color_str, -1, ctx) < 0)
92  return AVERROR(EINVAL);
93 
94  if (!s->invert_color) {
95  s->yuv_color[Y] = RGB_TO_Y_CCIR(rgba_color[0], rgba_color[1], rgba_color[2]);
96  s->yuv_color[U] = RGB_TO_U_CCIR(rgba_color[0], rgba_color[1], rgba_color[2], 0);
97  s->yuv_color[V] = RGB_TO_V_CCIR(rgba_color[0], rgba_color[1], rgba_color[2], 0);
98  s->yuv_color[A] = rgba_color[3];
99  }
100 
101  return 0;
102 }
103 
105 {
106  static const enum AVPixelFormat pix_fmts[] = {
112  };
113 
115  return 0;
116 }
117 
118 static int config_input(AVFilterLink *inlink)
119 {
120  AVFilterContext *ctx = inlink->dst;
121  DrawBoxContext *s = ctx->priv;
122  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
123  double var_values[VARS_NB], res;
124  char *expr;
125  int ret;
126  int i;
127 
128  s->hsub = desc->log2_chroma_w;
129  s->vsub = desc->log2_chroma_h;
130 
131  var_values[VAR_IN_H] = var_values[VAR_IH] = inlink->h;
132  var_values[VAR_IN_W] = var_values[VAR_IW] = inlink->w;
133  var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ? av_q2d(inlink->sample_aspect_ratio) : 1;
134  var_values[VAR_DAR] = (double)inlink->w / inlink->h * var_values[VAR_SAR];
135  var_values[VAR_HSUB] = s->hsub;
136  var_values[VAR_VSUB] = s->vsub;
137  var_values[VAR_X] = NAN;
138  var_values[VAR_Y] = NAN;
139  var_values[VAR_H] = NAN;
140  var_values[VAR_W] = NAN;
141  var_values[VAR_T] = NAN;
142 
143  for (i = 0; i <= NUM_EXPR_EVALS; i++) {
144  /* evaluate expressions, fail on last iteration */
145  if ((ret = av_expr_parse_and_eval(&res, (expr = s->x_expr),
146  var_names, var_values,
147  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0 && i == NUM_EXPR_EVALS)
148  goto fail;
149  s->x = var_values[VAR_X] = res;
150 
151  if ((ret = av_expr_parse_and_eval(&res, (expr = s->y_expr),
152  var_names, var_values,
153  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0 && i == NUM_EXPR_EVALS)
154  goto fail;
155  s->y = var_values[VAR_Y] = res;
156 
157  if ((ret = av_expr_parse_and_eval(&res, (expr = s->w_expr),
158  var_names, var_values,
159  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0 && i == NUM_EXPR_EVALS)
160  goto fail;
161  s->w = var_values[VAR_W] = res;
162 
163  if ((ret = av_expr_parse_and_eval(&res, (expr = s->h_expr),
164  var_names, var_values,
165  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0 && i == NUM_EXPR_EVALS)
166  goto fail;
167  s->h = var_values[VAR_H] = res;
168 
169  if ((ret = av_expr_parse_and_eval(&res, (expr = s->t_expr),
170  var_names, var_values,
171  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0 && i == NUM_EXPR_EVALS)
172  goto fail;
173  s->thickness = var_values[VAR_T] = res;
174  }
175 
176  /* if w or h are zero, use the input w/h */
177  s->w = (s->w > 0) ? s->w : inlink->w;
178  s->h = (s->h > 0) ? s->h : inlink->h;
179 
180  /* sanity check width and height */
181  if (s->w < 0 || s->h < 0) {
182  av_log(ctx, AV_LOG_ERROR, "Size values less than 0 are not acceptable.\n");
183  return AVERROR(EINVAL);
184  }
185 
186  av_log(ctx, AV_LOG_VERBOSE, "x:%d y:%d w:%d h:%d color:0x%02X%02X%02X%02X\n",
187  s->x, s->y, s->w, s->h,
188  s->yuv_color[Y], s->yuv_color[U], s->yuv_color[V], s->yuv_color[A]);
189 
190  return 0;
191 
192 fail:
193  av_log(ctx, AV_LOG_ERROR,
194  "Error when evaluating the expression '%s'.\n",
195  expr);
196  return ret;
197 }
198 
199 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
200 {
201  DrawBoxContext *s = inlink->dst->priv;
202  int plane, x, y, xb = s->x, yb = s->y;
203  unsigned char *row[4];
204 
205  for (y = FFMAX(yb, 0); y < frame->height && y < (yb + s->h); y++) {
206  row[0] = frame->data[0] + y * frame->linesize[0];
207 
208  for (plane = 1; plane < 3; plane++)
209  row[plane] = frame->data[plane] +
210  frame->linesize[plane] * (y >> s->vsub);
211 
212  if (s->invert_color) {
213  for (x = FFMAX(xb, 0); x < xb + s->w && x < frame->width; x++)
214  if ((y - yb < s->thickness) || (yb + s->h - 1 - y < s->thickness) ||
215  (x - xb < s->thickness) || (xb + s->w - 1 - x < s->thickness))
216  row[0][x] = 0xff - row[0][x];
217  } else {
218  for (x = FFMAX(xb, 0); x < xb + s->w && x < frame->width; x++) {
219  double alpha = (double)s->yuv_color[A] / 255;
220 
221  if ((y - yb < s->thickness) || (yb + s->h - 1 - y < s->thickness) ||
222  (x - xb < s->thickness) || (xb + s->w - 1 - x < s->thickness)) {
223  row[0][x ] = (1 - alpha) * row[0][x ] + alpha * s->yuv_color[Y];
224  row[1][x >> s->hsub] = (1 - alpha) * row[1][x >> s->hsub] + alpha * s->yuv_color[U];
225  row[2][x >> s->hsub] = (1 - alpha) * row[2][x >> s->hsub] + alpha * s->yuv_color[V];
226  }
227  }
228  }
229  }
230 
231  return ff_filter_frame(inlink->dst->outputs[0], frame);
232 }
233 
234 #define OFFSET(x) offsetof(DrawBoxContext, x)
235 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
236 
237 #if CONFIG_DRAWBOX_FILTER
238 
239 static const AVOption drawbox_options[] = {
240  { "x", "set horizontal position of the left box edge", OFFSET(x_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
241  { "y", "set vertical position of the top box edge", OFFSET(y_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
242  { "width", "set width of the box", OFFSET(w_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
243  { "w", "set width of the box", OFFSET(w_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
244  { "height", "set height of the box", OFFSET(h_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
245  { "h", "set height of the box", OFFSET(h_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
246  { "color", "set color of the box", OFFSET(color_str), AV_OPT_TYPE_STRING, { .str = "black" }, CHAR_MIN, CHAR_MAX, FLAGS },
247  { "c", "set color of the box", OFFSET(color_str), AV_OPT_TYPE_STRING, { .str = "black" }, CHAR_MIN, CHAR_MAX, FLAGS },
248  { "thickness", "set the box thickness", OFFSET(t_expr), AV_OPT_TYPE_STRING, { .str="3" }, CHAR_MIN, CHAR_MAX, FLAGS },
249  { "t", "set the box thickness", OFFSET(t_expr), AV_OPT_TYPE_STRING, { .str="3" }, CHAR_MIN, CHAR_MAX, FLAGS },
250  { NULL }
251 };
252 
253 AVFILTER_DEFINE_CLASS(drawbox);
254 
255 static const AVFilterPad drawbox_inputs[] = {
256  {
257  .name = "default",
258  .type = AVMEDIA_TYPE_VIDEO,
259  .config_props = config_input,
260  .filter_frame = filter_frame,
261  .needs_writable = 1,
262  },
263  { NULL }
264 };
265 
266 static const AVFilterPad drawbox_outputs[] = {
267  {
268  .name = "default",
269  .type = AVMEDIA_TYPE_VIDEO,
270  },
271  { NULL }
272 };
273 
274 AVFilter ff_vf_drawbox = {
275  .name = "drawbox",
276  .description = NULL_IF_CONFIG_SMALL("Draw a colored box on the input video."),
277  .priv_size = sizeof(DrawBoxContext),
278  .priv_class = &drawbox_class,
279  .init = init,
281  .inputs = drawbox_inputs,
282  .outputs = drawbox_outputs,
284 };
285 #endif /* CONFIG_DRAWBOX_FILTER */
286 
287 #if CONFIG_DRAWGRID_FILTER
288 static av_pure av_always_inline int pixel_belongs_to_grid(DrawBoxContext *drawgrid, int x, int y)
289 {
290  // x is horizontal (width) coord,
291  // y is vertical (height) coord
292  int x_modulo;
293  int y_modulo;
294 
295  // Abstract from the offset
296  x -= drawgrid->x;
297  y -= drawgrid->y;
298 
299  x_modulo = x % drawgrid->w;
300  y_modulo = y % drawgrid->h;
301 
302  // If x or y got negative, fix values to preserve logics
303  if (x_modulo < 0)
304  x_modulo += drawgrid->w;
305  if (y_modulo < 0)
306  y_modulo += drawgrid->h;
307 
308  return x_modulo < drawgrid->thickness // Belongs to vertical line
309  || y_modulo < drawgrid->thickness; // Belongs to horizontal line
310 }
311 
312 static int drawgrid_filter_frame(AVFilterLink *inlink, AVFrame *frame)
313 {
314  DrawBoxContext *drawgrid = inlink->dst->priv;
315  int plane, x, y;
316  uint8_t *row[4];
317 
318  for (y = 0; y < frame->height; y++) {
319  row[0] = frame->data[0] + y * frame->linesize[0];
320 
321  for (plane = 1; plane < 3; plane++)
322  row[plane] = frame->data[plane] +
323  frame->linesize[plane] * (y >> drawgrid->vsub);
324 
325  if (drawgrid->invert_color) {
326  for (x = 0; x < frame->width; x++)
327  if (pixel_belongs_to_grid(drawgrid, x, y))
328  row[0][x] = 0xff - row[0][x];
329  } else {
330  for (x = 0; x < frame->width; x++) {
331  double alpha = (double)drawgrid->yuv_color[A] / 255;
332 
333  if (pixel_belongs_to_grid(drawgrid, x, y)) {
334  row[0][x ] = (1 - alpha) * row[0][x ] + alpha * drawgrid->yuv_color[Y];
335  row[1][x >> drawgrid->hsub] = (1 - alpha) * row[1][x >> drawgrid->hsub] + alpha * drawgrid->yuv_color[U];
336  row[2][x >> drawgrid->hsub] = (1 - alpha) * row[2][x >> drawgrid->hsub] + alpha * drawgrid->yuv_color[V];
337  }
338  }
339  }
340  }
341 
342  return ff_filter_frame(inlink->dst->outputs[0], frame);
343 }
344 
345 static const AVOption drawgrid_options[] = {
346  { "x", "set horizontal offset", OFFSET(x_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
347  { "y", "set vertical offset", OFFSET(y_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
348  { "width", "set width of grid cell", OFFSET(w_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
349  { "w", "set width of grid cell", OFFSET(w_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
350  { "height", "set height of grid cell", OFFSET(h_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
351  { "h", "set height of grid cell", OFFSET(h_expr), AV_OPT_TYPE_STRING, { .str="0" }, CHAR_MIN, CHAR_MAX, FLAGS },
352  { "color", "set color of the grid", OFFSET(color_str), AV_OPT_TYPE_STRING, { .str = "black" }, CHAR_MIN, CHAR_MAX, FLAGS },
353  { "c", "set color of the grid", OFFSET(color_str), AV_OPT_TYPE_STRING, { .str = "black" }, CHAR_MIN, CHAR_MAX, FLAGS },
354  { "thickness", "set grid line thickness", OFFSET(t_expr), AV_OPT_TYPE_STRING, {.str="1"}, CHAR_MIN, CHAR_MAX, FLAGS },
355  { "t", "set grid line thickness", OFFSET(t_expr), AV_OPT_TYPE_STRING, {.str="1"}, CHAR_MIN, CHAR_MAX, FLAGS },
356  { NULL }
357 };
358 
359 AVFILTER_DEFINE_CLASS(drawgrid);
360 
361 static const AVFilterPad drawgrid_inputs[] = {
362  {
363  .name = "default",
364  .type = AVMEDIA_TYPE_VIDEO,
365  .config_props = config_input,
366  .filter_frame = drawgrid_filter_frame,
367  .needs_writable = 1,
368  },
369  { NULL }
370 };
371 
372 static const AVFilterPad drawgrid_outputs[] = {
373  {
374  .name = "default",
375  .type = AVMEDIA_TYPE_VIDEO,
376  },
377  { NULL }
378 };
379 
380 AVFilter ff_vf_drawgrid = {
381  .name = "drawgrid",
382  .description = NULL_IF_CONFIG_SMALL("Draw a colored grid on the input video."),
383  .priv_size = sizeof(DrawBoxContext),
384  .priv_class = &drawgrid_class,
385  .init = init,
387  .inputs = drawgrid_inputs,
388  .outputs = drawgrid_outputs,
390 };
391 
392 #endif /* CONFIG_DRAWGRID_FILTER */