FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
vf_blend.c
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2013 Paul B Mahol
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 #include "libavutil/imgutils.h"
22 #include "libavutil/eval.h"
23 #include "libavutil/opt.h"
24 #include "libavutil/pixfmt.h"
25 #include "avfilter.h"
26 #include "bufferqueue.h"
27 #include "formats.h"
28 #include "internal.h"
29 #include "dualinput.h"
30 #include "video.h"
31 
32 #define TOP 0
33 #define BOTTOM 1
34 
35 enum BlendMode {
62 };
63 
64 static const char *const var_names[] = { "X", "Y", "W", "H", "SW", "SH", "T", "N", "A", "B", "TOP", "BOTTOM", NULL };
66 
67 typedef struct FilterParams {
69  double opacity;
71  char *expr_str;
72  void (*blend)(const uint8_t *top, int top_linesize,
73  const uint8_t *bottom, int bottom_linesize,
74  uint8_t *dst, int dst_linesize,
75  int width, int start, int end,
76  struct FilterParams *param, double *values);
77 } FilterParams;
78 
79 typedef struct ThreadData {
80  const AVFrame *top, *bottom;
83  int plane;
84  int w, h;
86 } ThreadData;
87 
88 typedef struct {
89  const AVClass *class;
91  int hsub, vsub; ///< chroma subsampling values
92  int nb_planes;
93  char *all_expr;
95  double all_opacity;
96 
98 } BlendContext;
99 
100 #define OFFSET(x) offsetof(BlendContext, x)
101 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
102 
103 static const AVOption blend_options[] = {
104  { "c0_mode", "set component #0 blend mode", OFFSET(params[0].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},
105  { "c1_mode", "set component #1 blend mode", OFFSET(params[1].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},
106  { "c2_mode", "set component #2 blend mode", OFFSET(params[2].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},
107  { "c3_mode", "set component #3 blend mode", OFFSET(params[3].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},
108  { "all_mode", "set blend mode for all components", OFFSET(all_mode), AV_OPT_TYPE_INT, {.i64=-1},-1, BLEND_NB-1, FLAGS, "mode"},
109  { "addition", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_ADDITION}, 0, 0, FLAGS, "mode" },
110  { "and", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_AND}, 0, 0, FLAGS, "mode" },
111  { "average", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_AVERAGE}, 0, 0, FLAGS, "mode" },
112  { "burn", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_BURN}, 0, 0, FLAGS, "mode" },
113  { "darken", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DARKEN}, 0, 0, FLAGS, "mode" },
114  { "difference", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DIFFERENCE}, 0, 0, FLAGS, "mode" },
115  { "divide", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DIVIDE}, 0, 0, FLAGS, "mode" },
116  { "dodge", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DODGE}, 0, 0, FLAGS, "mode" },
117  { "exclusion", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_EXCLUSION}, 0, 0, FLAGS, "mode" },
118  { "hardlight", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_HARDLIGHT}, 0, 0, FLAGS, "mode" },
119  { "lighten", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_LIGHTEN}, 0, 0, FLAGS, "mode" },
120  { "multiply", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_MULTIPLY}, 0, 0, FLAGS, "mode" },
121  { "negation", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_NEGATION}, 0, 0, FLAGS, "mode" },
122  { "normal", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_NORMAL}, 0, 0, FLAGS, "mode" },
123  { "or", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_OR}, 0, 0, FLAGS, "mode" },
124  { "overlay", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_OVERLAY}, 0, 0, FLAGS, "mode" },
125  { "phoenix", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_PHOENIX}, 0, 0, FLAGS, "mode" },
126  { "pinlight", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_PINLIGHT}, 0, 0, FLAGS, "mode" },
127  { "reflect", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_REFLECT}, 0, 0, FLAGS, "mode" },
128  { "screen", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_SCREEN}, 0, 0, FLAGS, "mode" },
129  { "softlight", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_SOFTLIGHT}, 0, 0, FLAGS, "mode" },
130  { "subtract", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_SUBTRACT}, 0, 0, FLAGS, "mode" },
131  { "vividlight", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_VIVIDLIGHT}, 0, 0, FLAGS, "mode" },
132  { "xor", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_XOR}, 0, 0, FLAGS, "mode" },
133  { "c0_expr", "set color component #0 expression", OFFSET(params[0].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
134  { "c1_expr", "set color component #1 expression", OFFSET(params[1].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
135  { "c2_expr", "set color component #2 expression", OFFSET(params[2].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
136  { "c3_expr", "set color component #3 expression", OFFSET(params[3].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
137  { "all_expr", "set expression for all color components", OFFSET(all_expr), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
138  { "c0_opacity", "set color component #0 opacity", OFFSET(params[0].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },
139  { "c1_opacity", "set color component #1 opacity", OFFSET(params[1].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },
140  { "c2_opacity", "set color component #2 opacity", OFFSET(params[2].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },
141  { "c3_opacity", "set color component #3 opacity", OFFSET(params[3].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },
142  { "all_opacity", "set opacity for all color components", OFFSET(all_opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS},
143  { "shortest", "force termination when the shortest input terminates", OFFSET(dinput.shortest), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS },
144  { "repeatlast", "repeat last bottom frame", OFFSET(dinput.repeatlast), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS },
145  { NULL },
146 };
147 
148 AVFILTER_DEFINE_CLASS(blend);
149 
150 static void blend_normal(const uint8_t *top, int top_linesize,
151  const uint8_t *bottom, int bottom_linesize,
152  uint8_t *dst, int dst_linesize,
153  int width, int start, int end,
154  FilterParams *param, double *values)
155 {
156  av_image_copy_plane(dst, dst_linesize, top, top_linesize, width, end - start);
157 }
158 
159 #define DEFINE_BLEND(name, expr) \
160 static void blend_## name(const uint8_t *top, int top_linesize, \
161  const uint8_t *bottom, int bottom_linesize, \
162  uint8_t *dst, int dst_linesize, \
163  int width, int start, int end, \
164  FilterParams *param, double *values) \
165 { \
166  double opacity = param->opacity; \
167  int i, j; \
168  \
169  for (i = start; i < end; i++) { \
170  for (j = 0; j < width; j++) { \
171  dst[j] = top[j] + ((expr) - top[j]) * opacity; \
172  } \
173  dst += dst_linesize; \
174  top += top_linesize; \
175  bottom += bottom_linesize; \
176  } \
177 }
178 
179 #define A top[j]
180 #define B bottom[j]
181 
182 #define MULTIPLY(x, a, b) (x * ((a * b) / 255))
183 #define SCREEN(x, a, b) (255 - x * ((255 - a) * (255 - b) / 255))
184 #define BURN(a, b) ((a == 0) ? a : FFMAX(0, 255 - ((255 - b) << 8) / a))
185 #define DODGE(a, b) ((a == 255) ? a : FFMIN(255, ((b << 8) / (255 - a))))
186 
187 DEFINE_BLEND(addition, FFMIN(255, A + B))
188 DEFINE_BLEND(average, (A + B) / 2)
189 DEFINE_BLEND(subtract, FFMAX(0, A - B))
190 DEFINE_BLEND(multiply, MULTIPLY(1, A, B))
191 DEFINE_BLEND(negation, 255 - FFABS(255 - A - B))
192 DEFINE_BLEND(difference, FFABS(A - B))
193 DEFINE_BLEND(screen, SCREEN(1, A, B))
194 DEFINE_BLEND(overlay, (A < 128) ? MULTIPLY(2, A, B) : SCREEN(2, A, B))
195 DEFINE_BLEND(hardlight, (B < 128) ? MULTIPLY(2, B, A) : SCREEN(2, B, A))
196 DEFINE_BLEND(darken, FFMIN(A, B))
197 DEFINE_BLEND(lighten, FFMAX(A, B))
198 DEFINE_BLEND(divide, ((float)A / ((float)B) * 255))
199 DEFINE_BLEND(dodge, DODGE(A, B))
200 DEFINE_BLEND(burn, BURN(A, B))
201 DEFINE_BLEND(softlight, (A > 127) ? B + (255 - B) * (A - 127.5) / 127.5 * (0.5 - FFABS(B - 127.5) / 255): B - B * ((127.5 - A) / 127.5) * (0.5 - FFABS(B - 127.5)/255))
202 DEFINE_BLEND(exclusion, A + B - 2 * A * B / 255)
203 DEFINE_BLEND(pinlight, (B < 128) ? FFMIN(A, 2 * B) : FFMAX(A, 2 * (B - 128)))
204 DEFINE_BLEND(phoenix, FFMIN(A, B) - FFMAX(A, B) + 255)
205 DEFINE_BLEND(reflect, (B == 255) ? B : FFMIN(255, (A * A / (255 - B))))
206 DEFINE_BLEND(and, A & B)
207 DEFINE_BLEND(or, A | B)
208 DEFINE_BLEND(xor, A ^ B)
209 DEFINE_BLEND(vividlight, (B < 128) ? BURN(A, 2 * B) : DODGE(A, 2 * (B - 128)))
210 
211 static void blend_expr(const uint8_t *top, int top_linesize,
212  const uint8_t *bottom, int bottom_linesize,
213  uint8_t *dst, int dst_linesize,
214  int width, int start, int end,
215  FilterParams *param, double *values)
216 {
217  AVExpr *e = param->e;
218  int y, x;
219 
220  for (y = start; y < end; y++) {
221  values[VAR_Y] = y;
222  for (x = 0; x < width; x++) {
223  values[VAR_X] = x;
224  values[VAR_TOP] = values[VAR_A] = top[x];
225  values[VAR_BOTTOM] = values[VAR_B] = bottom[x];
226  dst[x] = av_expr_eval(e, values, NULL);
227  }
228  dst += dst_linesize;
229  top += top_linesize;
230  bottom += bottom_linesize;
231  }
232 }
233 
234 static int filter_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
235 {
236  ThreadData *td = arg;
237  int slice_start = (td->h * jobnr ) / nb_jobs;
238  int slice_end = (td->h * (jobnr+1)) / nb_jobs;
239  const uint8_t *top = td->top->data[td->plane];
240  const uint8_t *bottom = td->bottom->data[td->plane];
241  uint8_t *dst = td->dst->data[td->plane];
242  double values[VAR_VARS_NB];
243 
244  values[VAR_N] = td->inlink->frame_count;
245  values[VAR_T] = td->dst->pts == AV_NOPTS_VALUE ? NAN : td->dst->pts * av_q2d(td->inlink->time_base);
246  values[VAR_W] = td->w;
247  values[VAR_H] = td->h;
248  values[VAR_SW] = td->w / (double)td->dst->width;
249  values[VAR_SH] = td->h / (double)td->dst->height;
250 
251  td->param->blend(top + slice_start * td->top->linesize[td->plane],
252  td->top->linesize[td->plane],
253  bottom + slice_start * td->bottom->linesize[td->plane],
254  td->bottom->linesize[td->plane],
255  dst + slice_start * td->dst->linesize[td->plane],
256  td->dst->linesize[td->plane],
257  td->w, slice_start, slice_end, td->param, &values[0]);
258  return 0;
259 }
260 
262  const AVFrame *bottom_buf)
263 {
264  BlendContext *b = ctx->priv;
265  AVFilterLink *inlink = ctx->inputs[0];
266  AVFilterLink *outlink = ctx->outputs[0];
267  AVFrame *dst_buf;
268  int plane;
269 
270  dst_buf = ff_get_video_buffer(outlink, outlink->w, outlink->h);
271  if (!dst_buf)
272  return top_buf;
273  av_frame_copy_props(dst_buf, top_buf);
274 
275  for (plane = 0; plane < b->nb_planes; plane++) {
276  int hsub = plane == 1 || plane == 2 ? b->hsub : 0;
277  int vsub = plane == 1 || plane == 2 ? b->vsub : 0;
278  int outw = FF_CEIL_RSHIFT(dst_buf->width, hsub);
279  int outh = FF_CEIL_RSHIFT(dst_buf->height, vsub);
280  FilterParams *param = &b->params[plane];
281  ThreadData td = { .top = top_buf, .bottom = bottom_buf, .dst = dst_buf,
282  .w = outw, .h = outh, .param = param, .plane = plane,
283  .inlink = inlink };
284 
285  ctx->internal->execute(ctx, filter_slice, &td, NULL, FFMIN(outh, ctx->graph->nb_threads));
286  }
287 
288  av_frame_free(&top_buf);
289 
290  return dst_buf;
291 }
292 
293 static av_cold int init(AVFilterContext *ctx)
294 {
295  BlendContext *b = ctx->priv;
296  int ret, plane;
297 
298  for (plane = 0; plane < FF_ARRAY_ELEMS(b->params); plane++) {
299  FilterParams *param = &b->params[plane];
300 
301  if (b->all_mode >= 0)
302  param->mode = b->all_mode;
303  if (b->all_opacity < 1)
304  param->opacity = b->all_opacity;
305 
306  switch (param->mode) {
307  case BLEND_ADDITION: param->blend = blend_addition; break;
308  case BLEND_AND: param->blend = blend_and; break;
309  case BLEND_AVERAGE: param->blend = blend_average; break;
310  case BLEND_BURN: param->blend = blend_burn; break;
311  case BLEND_DARKEN: param->blend = blend_darken; break;
312  case BLEND_DIFFERENCE: param->blend = blend_difference; break;
313  case BLEND_DIVIDE: param->blend = blend_divide; break;
314  case BLEND_DODGE: param->blend = blend_dodge; break;
315  case BLEND_EXCLUSION: param->blend = blend_exclusion; break;
316  case BLEND_HARDLIGHT: param->blend = blend_hardlight; break;
317  case BLEND_LIGHTEN: param->blend = blend_lighten; break;
318  case BLEND_MULTIPLY: param->blend = blend_multiply; break;
319  case BLEND_NEGATION: param->blend = blend_negation; break;
320  case BLEND_NORMAL: param->blend = blend_normal; break;
321  case BLEND_OR: param->blend = blend_or; break;
322  case BLEND_OVERLAY: param->blend = blend_overlay; break;
323  case BLEND_PHOENIX: param->blend = blend_phoenix; break;
324  case BLEND_PINLIGHT: param->blend = blend_pinlight; break;
325  case BLEND_REFLECT: param->blend = blend_reflect; break;
326  case BLEND_SCREEN: param->blend = blend_screen; break;
327  case BLEND_SOFTLIGHT: param->blend = blend_softlight; break;
328  case BLEND_SUBTRACT: param->blend = blend_subtract; break;
329  case BLEND_VIVIDLIGHT: param->blend = blend_vividlight; break;
330  case BLEND_XOR: param->blend = blend_xor; break;
331  }
332 
333  if (b->all_expr && !param->expr_str) {
334  param->expr_str = av_strdup(b->all_expr);
335  if (!param->expr_str)
336  return AVERROR(ENOMEM);
337  }
338  if (param->expr_str) {
339  ret = av_expr_parse(&param->e, param->expr_str, var_names,
340  NULL, NULL, NULL, NULL, 0, ctx);
341  if (ret < 0)
342  return ret;
343  param->blend = blend_expr;
344  }
345  }
346 
348  return 0;
349 }
350 
352 {
353  static const enum AVPixelFormat pix_fmts[] = {
358  };
359 
361  return 0;
362 }
363 
364 static int config_output(AVFilterLink *outlink)
365 {
366  AVFilterContext *ctx = outlink->src;
367  AVFilterLink *toplink = ctx->inputs[TOP];
368  AVFilterLink *bottomlink = ctx->inputs[BOTTOM];
369  BlendContext *b = ctx->priv;
370  const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(toplink->format);
371 
372  if (toplink->format != bottomlink->format) {
373  av_log(ctx, AV_LOG_ERROR, "inputs must be of same pixel format\n");
374  return AVERROR(EINVAL);
375  }
376  if (toplink->w != bottomlink->w ||
377  toplink->h != bottomlink->h ||
378  toplink->sample_aspect_ratio.num != bottomlink->sample_aspect_ratio.num ||
379  toplink->sample_aspect_ratio.den != bottomlink->sample_aspect_ratio.den) {
380  av_log(ctx, AV_LOG_ERROR, "First input link %s parameters "
381  "(size %dx%d, SAR %d:%d) do not match the corresponding "
382  "second input link %s parameters (%dx%d, SAR %d:%d)\n",
383  ctx->input_pads[TOP].name, toplink->w, toplink->h,
384  toplink->sample_aspect_ratio.num,
385  toplink->sample_aspect_ratio.den,
386  ctx->input_pads[BOTTOM].name, bottomlink->w, bottomlink->h,
387  bottomlink->sample_aspect_ratio.num,
388  bottomlink->sample_aspect_ratio.den);
389  return AVERROR(EINVAL);
390  }
391 
392  outlink->w = toplink->w;
393  outlink->h = toplink->h;
394  outlink->time_base = toplink->time_base;
395  outlink->sample_aspect_ratio = toplink->sample_aspect_ratio;
396  outlink->frame_rate = toplink->frame_rate;
397 
398  b->hsub = pix_desc->log2_chroma_w;
399  b->vsub = pix_desc->log2_chroma_h;
401 
402  return 0;
403 }
404 
405 static av_cold void uninit(AVFilterContext *ctx)
406 {
407  BlendContext *b = ctx->priv;
408  int i;
409 
411  for (i = 0; i < FF_ARRAY_ELEMS(b->params); i++)
412  av_expr_free(b->params[i].e);
413 }
414 
415 static int request_frame(AVFilterLink *outlink)
416 {
417  BlendContext *b = outlink->src->priv;
418  return ff_dualinput_request_frame(&b->dinput, outlink);
419 }
420 
422 {
423  BlendContext *b = inlink->dst->priv;
424  return ff_dualinput_filter_frame_main(&b->dinput, inlink, buf);
425 }
426 
428 {
429  BlendContext *b = inlink->dst->priv;
430  return ff_dualinput_filter_frame_second(&b->dinput, inlink, buf);
431 }
432 
433 static const AVFilterPad blend_inputs[] = {
434  {
435  .name = "top",
436  .type = AVMEDIA_TYPE_VIDEO,
437  .filter_frame = filter_frame_top,
438  },{
439  .name = "bottom",
440  .type = AVMEDIA_TYPE_VIDEO,
441  .filter_frame = filter_frame_bottom,
442  },
443  { NULL }
444 };
445 
446 static const AVFilterPad blend_outputs[] = {
447  {
448  .name = "default",
449  .type = AVMEDIA_TYPE_VIDEO,
450  .config_props = config_output,
451  .request_frame = request_frame,
452  },
453  { NULL }
454 };
455 
457  .name = "blend",
458  .description = NULL_IF_CONFIG_SMALL("Blend two video frames into each other."),
459  .init = init,
460  .uninit = uninit,
461  .priv_size = sizeof(BlendContext),
463  .inputs = blend_inputs,
464  .outputs = blend_outputs,
465  .priv_class = &blend_class,
467 };