vf_pad.c
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1 /*
2  * Copyright (c) 2008 vmrsss
3  * Copyright (c) 2009 Stefano Sabatini
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
27 #include "avfilter.h"
28 #include "formats.h"
29 #include "internal.h"
30 #include "video.h"
31 #include "libavutil/avstring.h"
32 #include "libavutil/common.h"
33 #include "libavutil/eval.h"
34 #include "libavutil/pixdesc.h"
35 #include "libavutil/colorspace.h"
36 #include "libavutil/avassert.h"
37 #include "libavutil/imgutils.h"
38 #include "libavutil/parseutils.h"
39 #include "libavutil/mathematics.h"
40 #include "drawutils.h"
41 
42 static const char *const var_names[] = {
43  "PI",
44  "PHI",
45  "E",
46  "in_w", "iw",
47  "in_h", "ih",
48  "out_w", "ow",
49  "out_h", "oh",
50  "x",
51  "y",
52  "a",
53  "hsub",
54  "vsub",
55  NULL
56 };
57 
58 enum var_name {
72 };
73 
75 {
76  static const enum AVPixelFormat pix_fmts[] = {
80 
87 
89  };
90 
92  return 0;
93 }
94 
95 typedef struct {
96  int w, h;
97  int x, y;
98  int in_w, in_h;
99 
100  char w_expr[256];
101  char h_expr[256];
102  char x_expr[256];
103  char y_expr[256];
104 
107  int line_step[4];
108  int hsub, vsub;
109 } PadContext;
110 
111 static av_cold int init(AVFilterContext *ctx, const char *args)
112 {
113  PadContext *pad = ctx->priv;
114  char color_string[128] = "black";
115 
116  av_strlcpy(pad->w_expr, "iw", sizeof(pad->w_expr));
117  av_strlcpy(pad->h_expr, "ih", sizeof(pad->h_expr));
118  av_strlcpy(pad->x_expr, "0" , sizeof(pad->w_expr));
119  av_strlcpy(pad->y_expr, "0" , sizeof(pad->h_expr));
120 
121  if (args)
122  sscanf(args, "%255[^:]:%255[^:]:%255[^:]:%255[^:]:%255s",
123  pad->w_expr, pad->h_expr, pad->x_expr, pad->y_expr, color_string);
124 
125  if (av_parse_color(pad->color, color_string, -1, ctx) < 0)
126  return AVERROR(EINVAL);
127 
128  return 0;
129 }
130 
131 static av_cold void uninit(AVFilterContext *ctx)
132 {
133  PadContext *pad = ctx->priv;
134  int i;
135 
136  for (i = 0; i < 4; i++) {
137  av_freep(&pad->line[i]);
138  pad->line_step[i] = 0;
139  }
140 }
141 
142 static int config_input(AVFilterLink *inlink)
143 {
144  AVFilterContext *ctx = inlink->dst;
145  PadContext *pad = ctx->priv;
146  const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
147  uint8_t rgba_color[4];
148  int ret, is_packed_rgba;
149  double var_values[VARS_NB], res;
150  char *expr;
151 
152  pad->hsub = pix_desc->log2_chroma_w;
153  pad->vsub = pix_desc->log2_chroma_h;
154 
155  var_values[VAR_PI] = M_PI;
156  var_values[VAR_PHI] = M_PHI;
157  var_values[VAR_E] = M_E;
158  var_values[VAR_IN_W] = var_values[VAR_IW] = inlink->w;
159  var_values[VAR_IN_H] = var_values[VAR_IH] = inlink->h;
160  var_values[VAR_OUT_W] = var_values[VAR_OW] = NAN;
161  var_values[VAR_OUT_H] = var_values[VAR_OH] = NAN;
162  var_values[VAR_A] = (double) inlink->w / inlink->h;
163  var_values[VAR_HSUB] = 1<<pad->hsub;
164  var_values[VAR_VSUB] = 1<<pad->vsub;
165 
166  /* evaluate width and height */
167  av_expr_parse_and_eval(&res, (expr = pad->w_expr),
168  var_names, var_values,
169  NULL, NULL, NULL, NULL, NULL, 0, ctx);
170  pad->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
171  if ((ret = av_expr_parse_and_eval(&res, (expr = pad->h_expr),
172  var_names, var_values,
173  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
174  goto eval_fail;
175  pad->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = res;
176  /* evaluate the width again, as it may depend on the evaluated output height */
177  if ((ret = av_expr_parse_and_eval(&res, (expr = pad->w_expr),
178  var_names, var_values,
179  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
180  goto eval_fail;
181  pad->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
182 
183  /* evaluate x and y */
184  av_expr_parse_and_eval(&res, (expr = pad->x_expr),
185  var_names, var_values,
186  NULL, NULL, NULL, NULL, NULL, 0, ctx);
187  pad->x = var_values[VAR_X] = res;
188  if ((ret = av_expr_parse_and_eval(&res, (expr = pad->y_expr),
189  var_names, var_values,
190  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
191  goto eval_fail;
192  pad->y = var_values[VAR_Y] = res;
193  /* evaluate x again, as it may depend on the evaluated y value */
194  if ((ret = av_expr_parse_and_eval(&res, (expr = pad->x_expr),
195  var_names, var_values,
196  NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
197  goto eval_fail;
198  pad->x = var_values[VAR_X] = res;
199 
200  /* sanity check params */
201  if (pad->w < 0 || pad->h < 0 || pad->x < 0 || pad->y < 0) {
202  av_log(ctx, AV_LOG_ERROR, "Negative values are not acceptable.\n");
203  return AVERROR(EINVAL);
204  }
205 
206  if (!pad->w)
207  pad->w = inlink->w;
208  if (!pad->h)
209  pad->h = inlink->h;
210 
211  pad->w &= ~((1 << pad->hsub) - 1);
212  pad->h &= ~((1 << pad->vsub) - 1);
213  pad->x &= ~((1 << pad->hsub) - 1);
214  pad->y &= ~((1 << pad->vsub) - 1);
215 
216  pad->in_w = inlink->w & ~((1 << pad->hsub) - 1);
217  pad->in_h = inlink->h & ~((1 << pad->vsub) - 1);
218 
219  memcpy(rgba_color, pad->color, sizeof(rgba_color));
220  ff_fill_line_with_color(pad->line, pad->line_step, pad->w, pad->color,
221  inlink->format, rgba_color, &is_packed_rgba, NULL);
222 
223  av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d -> w:%d h:%d x:%d y:%d color:0x%02X%02X%02X%02X[%s]\n",
224  inlink->w, inlink->h, pad->w, pad->h, pad->x, pad->y,
225  pad->color[0], pad->color[1], pad->color[2], pad->color[3],
226  is_packed_rgba ? "rgba" : "yuva");
227 
228  if (pad->x < 0 || pad->y < 0 ||
229  pad->w <= 0 || pad->h <= 0 ||
230  (unsigned)pad->x + (unsigned)inlink->w > pad->w ||
231  (unsigned)pad->y + (unsigned)inlink->h > pad->h) {
232  av_log(ctx, AV_LOG_ERROR,
233  "Input area %d:%d:%d:%d not within the padded area 0:0:%d:%d or zero-sized\n",
234  pad->x, pad->y, pad->x + inlink->w, pad->y + inlink->h, pad->w, pad->h);
235  return AVERROR(EINVAL);
236  }
237 
238  return 0;
239 
240 eval_fail:
241  av_log(NULL, AV_LOG_ERROR,
242  "Error when evaluating the expression '%s'\n", expr);
243  return ret;
244 
245 }
246 
247 static int config_output(AVFilterLink *outlink)
248 {
249  PadContext *pad = outlink->src->priv;
250 
251  outlink->w = pad->w;
252  outlink->h = pad->h;
253  return 0;
254 }
255 
256 static AVFilterBufferRef *get_video_buffer(AVFilterLink *inlink, int perms, int w, int h)
257 {
258  PadContext *pad = inlink->dst->priv;
259 
260  AVFilterBufferRef *picref = ff_get_video_buffer(inlink->dst->outputs[0], perms,
261  w + (pad->w - pad->in_w),
262  h + (pad->h - pad->in_h));
263  int plane;
264 
265  if (!picref)
266  return NULL;
267 
268  picref->video->w = w;
269  picref->video->h = h;
270 
271  for (plane = 0; plane < 4 && picref->data[plane]; plane++) {
272  int hsub = (plane == 1 || plane == 2) ? pad->hsub : 0;
273  int vsub = (plane == 1 || plane == 2) ? pad->vsub : 0;
274 
275  picref->data[plane] += (pad->x >> hsub) * pad->line_step[plane] +
276  (pad->y >> vsub) * picref->linesize[plane];
277  }
278 
279  return picref;
280 }
281 
282 static int does_clip(PadContext *pad, AVFilterBufferRef *outpicref, int plane, int hsub, int vsub, int x, int y)
283 {
284  int64_t x_in_buf, y_in_buf;
285 
286  x_in_buf = outpicref->data[plane] - outpicref->buf->data[plane]
287  + (x >> hsub) * pad ->line_step[plane]
288  + (y >> vsub) * outpicref->linesize [plane];
289 
290  if(x_in_buf < 0 || x_in_buf % pad->line_step[plane])
291  return 1;
292  x_in_buf /= pad->line_step[plane];
293 
294  av_assert0(outpicref->buf->linesize[plane]>0); //while reference can use negative linesize the main buffer should not
295 
296  y_in_buf = x_in_buf / outpicref->buf->linesize[plane];
297  x_in_buf %= outpicref->buf->linesize[plane];
298 
299  if( y_in_buf<<vsub >= outpicref->buf->h
300  || x_in_buf<<hsub >= outpicref->buf->w)
301  return 1;
302  return 0;
303 }
304 
306 {
307  PadContext *pad = inlink->dst->priv;
308  AVFilterBufferRef *out = avfilter_ref_buffer(in, ~0);
309  int plane, needs_copy;
310 
311  if (!out) {
313  return AVERROR(ENOMEM);
314  }
315 
316  for (plane = 0; plane < 4 && out->data[plane]; plane++) {
317  int hsub = (plane == 1 || plane == 2) ? pad->hsub : 0;
318  int vsub = (plane == 1 || plane == 2) ? pad->vsub : 0;
319 
320  av_assert0(out->buf->w > 0 && out->buf->h > 0);
321 
322  if (out->format != out->buf->format) //unsupported currently
323  break;
324 
325  out->data[plane] -= (pad->x >> hsub) * pad->line_step[plane] +
326  (pad->y >> vsub) * out->linesize [plane];
327 
328  if (does_clip(pad, out, plane, hsub, vsub, 0, 0) ||
329  does_clip(pad, out, plane, hsub, vsub, 0, pad->h - 1) ||
330  does_clip(pad, out, plane, hsub, vsub, pad->w - 1, 0) ||
331  does_clip(pad, out, plane, hsub, vsub, pad->w - 1, pad->h - 1))
332  break;
333  }
334  needs_copy = plane < 4 && out->data[plane];
335  if (needs_copy) {
336  av_log(inlink->dst, AV_LOG_DEBUG, "Direct padding impossible allocating new frame\n");
339  FFMAX(inlink->w, pad->w),
340  FFMAX(inlink->h, pad->h));
341  if (!out) {
343  return AVERROR(ENOMEM);
344  }
345 
347  }
348 
349  out->video->w = pad->w;
350  out->video->h = pad->h;
351 
352  /* top bar */
353  if (pad->y) {
354  ff_draw_rectangle(out->data, out->linesize,
355  pad->line, pad->line_step, pad->hsub, pad->vsub,
356  0, 0, pad->w, pad->y);
357  }
358 
359  /* bottom bar */
360  if (pad->h > pad->y + pad->in_h) {
361  ff_draw_rectangle(out->data, out->linesize,
362  pad->line, pad->line_step, pad->hsub, pad->vsub,
363  0, pad->y + pad->in_h, pad->w, pad->h - pad->y - pad->in_h);
364  }
365 
366  /* left border */
367  ff_draw_rectangle(out->data, out->linesize, pad->line, pad->line_step,
368  pad->hsub, pad->vsub, 0, pad->y, pad->x, in->video->h);
369 
370  if (needs_copy) {
371  ff_copy_rectangle(out->data, out->linesize, in->data, in->linesize,
372  pad->line_step, pad->hsub, pad->vsub,
373  pad->x, pad->y, 0, in->video->w, in->video->h);
374  }
375 
376  /* right border */
377  ff_draw_rectangle(out->data, out->linesize,
378  pad->line, pad->line_step, pad->hsub, pad->vsub,
379  pad->x + pad->in_w, pad->y, pad->w - pad->x - pad->in_w,
380  in->video->h);
381 
383  return ff_filter_frame(inlink->dst->outputs[0], out);
384 }
385 
387  {
388  .name = "default",
389  .type = AVMEDIA_TYPE_VIDEO,
390  .config_props = config_input,
391  .get_video_buffer = get_video_buffer,
392  .filter_frame = filter_frame,
393  },
394  { NULL }
395 };
396 
398  {
399  .name = "default",
400  .type = AVMEDIA_TYPE_VIDEO,
401  .config_props = config_output,
402  },
403  { NULL }
404 };
405 
407  .name = "pad",
408  .description = NULL_IF_CONFIG_SMALL("Pad input image to width:height[:x:y[:color]] (default x and y: 0, default color: black)."),
409 
410  .priv_size = sizeof(PadContext),
411  .init = init,
412  .uninit = uninit,
414 
415  .inputs = avfilter_vf_pad_inputs,
416 
417  .outputs = avfilter_vf_pad_outputs,
418 };