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vf_curves.c
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1 /*
2  * Copyright (c) 2013 Clément Bœsch
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/opt.h"
22 #include "libavutil/bprint.h"
23 #include "libavutil/eval.h"
24 #include "libavutil/file.h"
25 #include "libavutil/intreadwrite.h"
26 #include "libavutil/avassert.h"
27 #include "libavutil/pixdesc.h"
28 #include "avfilter.h"
29 #include "drawutils.h"
30 #include "formats.h"
31 #include "internal.h"
32 #include "video.h"
33 
34 #define R 0
35 #define G 1
36 #define B 2
37 #define A 3
38 
39 struct keypoint {
40  double x, y;
41  struct keypoint *next;
42 };
43 
44 #define NB_COMP 3
45 
46 enum preset {
59 };
60 
61 typedef struct {
62  const AVClass *class;
63  enum preset preset;
64  char *comp_points_str[NB_COMP + 1];
66  uint8_t graph[NB_COMP + 1][256];
67  char *psfile;
68  uint8_t rgba_map[4];
69  int step;
71 
72 typedef struct ThreadData {
74 } ThreadData;
75 
76 #define OFFSET(x) offsetof(CurvesContext, x)
77 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
78 static const AVOption curves_options[] = {
79  { "preset", "select a color curves preset", OFFSET(preset), AV_OPT_TYPE_INT, {.i64=PRESET_NONE}, PRESET_NONE, NB_PRESETS-1, FLAGS, "preset_name" },
80  { "none", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_NONE}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
81  { "color_negative", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_COLOR_NEGATIVE}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
82  { "cross_process", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_CROSS_PROCESS}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
83  { "darker", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_DARKER}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
84  { "increase_contrast", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_INCREASE_CONTRAST}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
85  { "lighter", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_LIGHTER}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
86  { "linear_contrast", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_LINEAR_CONTRAST}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
87  { "medium_contrast", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_MEDIUM_CONTRAST}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
88  { "negative", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_NEGATIVE}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
89  { "strong_contrast", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_STRONG_CONTRAST}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
90  { "vintage", NULL, 0, AV_OPT_TYPE_CONST, {.i64=PRESET_VINTAGE}, INT_MIN, INT_MAX, FLAGS, "preset_name" },
91  { "master","set master points coordinates",OFFSET(comp_points_str[NB_COMP]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
92  { "m", "set master points coordinates",OFFSET(comp_points_str[NB_COMP]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
93  { "red", "set red points coordinates", OFFSET(comp_points_str[0]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
94  { "r", "set red points coordinates", OFFSET(comp_points_str[0]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
95  { "green", "set green points coordinates", OFFSET(comp_points_str[1]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
96  { "g", "set green points coordinates", OFFSET(comp_points_str[1]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
97  { "blue", "set blue points coordinates", OFFSET(comp_points_str[2]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
98  { "b", "set blue points coordinates", OFFSET(comp_points_str[2]), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
99  { "all", "set points coordinates for all components", OFFSET(comp_points_str_all), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
100  { "psfile", "set Photoshop curves file name", OFFSET(psfile), AV_OPT_TYPE_STRING, {.str=NULL}, .flags = FLAGS },
101  { NULL }
102 };
103 
104 AVFILTER_DEFINE_CLASS(curves);
105 
106 static const struct {
107  const char *r;
108  const char *g;
109  const char *b;
110  const char *master;
111 } curves_presets[] = {
113  "0/1 0.129/1 0.466/0.498 0.725/0 1/0",
114  "0/1 0.109/1 0.301/0.498 0.517/0 1/0",
115  "0/1 0.098/1 0.235/0.498 0.423/0 1/0",
116  },
118  "0.25/0.156 0.501/0.501 0.686/0.745",
119  "0.25/0.188 0.38/0.501 0.745/0.815 1/0.815",
120  "0.231/0.094 0.709/0.874",
121  },
122  [PRESET_DARKER] = { .master = "0.5/0.4" },
123  [PRESET_INCREASE_CONTRAST] = { .master = "0.149/0.066 0.831/0.905 0.905/0.98" },
124  [PRESET_LIGHTER] = { .master = "0.4/0.5" },
125  [PRESET_LINEAR_CONTRAST] = { .master = "0.305/0.286 0.694/0.713" },
126  [PRESET_MEDIUM_CONTRAST] = { .master = "0.286/0.219 0.639/0.643" },
127  [PRESET_NEGATIVE] = { .master = "0/1 1/0" },
128  [PRESET_STRONG_CONTRAST] = { .master = "0.301/0.196 0.592/0.6 0.686/0.737" },
129  [PRESET_VINTAGE] = {
130  "0/0.11 0.42/0.51 1/0.95",
131  "0.50/0.48",
132  "0/0.22 0.49/0.44 1/0.8",
133  }
134 };
135 
136 static struct keypoint *make_point(double x, double y, struct keypoint *next)
137 {
138  struct keypoint *point = av_mallocz(sizeof(*point));
139 
140  if (!point)
141  return NULL;
142  point->x = x;
143  point->y = y;
144  point->next = next;
145  return point;
146 }
147 
148 static int parse_points_str(AVFilterContext *ctx, struct keypoint **points, const char *s)
149 {
150  char *p = (char *)s; // strtod won't alter the string
151  struct keypoint *last = NULL;
152 
153  /* construct a linked list based on the key points string */
154  while (p && *p) {
155  struct keypoint *point = make_point(0, 0, NULL);
156  if (!point)
157  return AVERROR(ENOMEM);
158  point->x = av_strtod(p, &p); if (p && *p) p++;
159  point->y = av_strtod(p, &p); if (p && *p) p++;
160  if (point->x < 0 || point->x > 1 || point->y < 0 || point->y > 1) {
161  av_log(ctx, AV_LOG_ERROR, "Invalid key point coordinates (%f;%f), "
162  "x and y must be in the [0;1] range.\n", point->x, point->y);
163  return AVERROR(EINVAL);
164  }
165  if (!*points)
166  *points = point;
167  if (last) {
168  if ((int)(last->x * 255) >= (int)(point->x * 255)) {
169  av_log(ctx, AV_LOG_ERROR, "Key point coordinates (%f;%f) "
170  "and (%f;%f) are too close from each other or not "
171  "strictly increasing on the x-axis\n",
172  last->x, last->y, point->x, point->y);
173  return AVERROR(EINVAL);
174  }
175  last->next = point;
176  }
177  last = point;
178  }
179 
180  /* auto insert first key point if missing at x=0 */
181  if (!*points) {
182  last = make_point(0, 0, NULL);
183  if (!last)
184  return AVERROR(ENOMEM);
185  last->x = last->y = 0;
186  *points = last;
187  } else if ((*points)->x != 0.) {
188  struct keypoint *newfirst = make_point(0, 0, *points);
189  if (!newfirst)
190  return AVERROR(ENOMEM);
191  *points = newfirst;
192  }
193 
194  av_assert0(last);
195 
196  /* auto insert last key point if missing at x=1 */
197  if (last->x != 1.) {
198  struct keypoint *point = make_point(1, 1, NULL);
199  if (!point)
200  return AVERROR(ENOMEM);
201  last->next = point;
202  }
203 
204  return 0;
205 }
206 
207 static int get_nb_points(const struct keypoint *d)
208 {
209  int n = 0;
210  while (d) {
211  n++;
212  d = d->next;
213  }
214  return n;
215 }
216 
217 /**
218  * Natural cubic spline interpolation
219  * Finding curves using Cubic Splines notes by Steven Rauch and John Stockie.
220  * @see http://people.math.sfu.ca/~stockie/teaching/macm316/notes/splines.pdf
221  */
222 static int interpolate(AVFilterContext *ctx, uint8_t *y, const struct keypoint *points)
223 {
224  int i, ret = 0;
225  const struct keypoint *point;
226  double xprev = 0;
227 
228  int n = get_nb_points(points); // number of splines
229 
230  double (*matrix)[3] = av_calloc(n, sizeof(*matrix));
231  double *h = av_malloc((n - 1) * sizeof(*h));
232  double *r = av_calloc(n, sizeof(*r));
233 
234  if (!matrix || !h || !r) {
235  ret = AVERROR(ENOMEM);
236  goto end;
237  }
238 
239  /* h(i) = x(i+1) - x(i) */
240  i = -1;
241  for (point = points; point; point = point->next) {
242  if (i != -1)
243  h[i] = point->x - xprev;
244  xprev = point->x;
245  i++;
246  }
247 
248  /* right-side of the polynomials, will be modified to contains the solution */
249  point = points;
250  for (i = 1; i < n - 1; i++) {
251  double yp = point->y,
252  yc = point->next->y,
253  yn = point->next->next->y;
254  r[i] = 6 * ((yn-yc)/h[i] - (yc-yp)/h[i-1]);
255  point = point->next;
256  }
257 
258 #define BD 0 /* sub diagonal (below main) */
259 #define MD 1 /* main diagonal (center) */
260 #define AD 2 /* sup diagonal (above main) */
261 
262  /* left side of the polynomials into a tridiagonal matrix. */
263  matrix[0][MD] = matrix[n - 1][MD] = 1;
264  for (i = 1; i < n - 1; i++) {
265  matrix[i][BD] = h[i-1];
266  matrix[i][MD] = 2 * (h[i-1] + h[i]);
267  matrix[i][AD] = h[i];
268  }
269 
270  /* tridiagonal solving of the linear system */
271  for (i = 1; i < n; i++) {
272  double den = matrix[i][MD] - matrix[i][BD] * matrix[i-1][AD];
273  double k = den ? 1./den : 1.;
274  matrix[i][AD] *= k;
275  r[i] = (r[i] - matrix[i][BD] * r[i - 1]) * k;
276  }
277  for (i = n - 2; i >= 0; i--)
278  r[i] = r[i] - matrix[i][AD] * r[i + 1];
279 
280  /* compute the graph with x=[0..255] */
281  i = 0;
282  point = points;
283  av_assert0(point->next); // always at least 2 key points
284  while (point->next) {
285  double yc = point->y;
286  double yn = point->next->y;
287 
288  double a = yc;
289  double b = (yn-yc)/h[i] - h[i]*r[i]/2. - h[i]*(r[i+1]-r[i])/6.;
290  double c = r[i] / 2.;
291  double d = (r[i+1] - r[i]) / (6.*h[i]);
292 
293  int x;
294  int x_start = point->x * 255;
295  int x_end = point->next->x * 255;
296 
297  av_assert0(x_start >= 0 && x_start <= 255 &&
298  x_end >= 0 && x_end <= 255);
299 
300  for (x = x_start; x <= x_end; x++) {
301  double xx = (x - x_start) * 1/255.;
302  double yy = a + b*xx + c*xx*xx + d*xx*xx*xx;
303  y[x] = av_clipf(yy, 0, 1) * 255;
304  av_log(ctx, AV_LOG_DEBUG, "f(%f)=%f -> y[%d]=%d\n", xx, yy, x, y[x]);
305  }
306 
307  point = point->next;
308  i++;
309  }
310 
311 end:
312  av_free(matrix);
313  av_free(h);
314  av_free(r);
315  return ret;
316 }
317 
318 static int parse_psfile(AVFilterContext *ctx, const char *fname)
319 {
320  CurvesContext *curves = ctx->priv;
321  uint8_t *buf;
322  size_t size;
323  int i, ret, av_unused(version), nb_curves;
324  AVBPrint ptstr;
325  static const int comp_ids[] = {3, 0, 1, 2};
326 
328 
329  ret = av_file_map(fname, &buf, &size, 0, NULL);
330  if (ret < 0)
331  return ret;
332 
333 #define READ16(dst) do { \
334  if (size < 2) { \
335  ret = AVERROR_INVALIDDATA; \
336  goto end; \
337  } \
338  dst = AV_RB16(buf); \
339  buf += 2; \
340  size -= 2; \
341 } while (0)
342 
343  READ16(version);
344  READ16(nb_curves);
345  for (i = 0; i < FFMIN(nb_curves, FF_ARRAY_ELEMS(comp_ids)); i++) {
346  int nb_points, n;
347  av_bprint_clear(&ptstr);
348  READ16(nb_points);
349  for (n = 0; n < nb_points; n++) {
350  int y, x;
351  READ16(y);
352  READ16(x);
353  av_bprintf(&ptstr, "%f/%f ", x / 255., y / 255.);
354  }
355  if (*ptstr.str) {
356  char **pts = &curves->comp_points_str[comp_ids[i]];
357  if (!*pts) {
358  *pts = av_strdup(ptstr.str);
359  av_log(ctx, AV_LOG_DEBUG, "curves %d (intid=%d) [%d points]: [%s]\n",
360  i, comp_ids[i], nb_points, *pts);
361  if (!*pts) {
362  ret = AVERROR(ENOMEM);
363  goto end;
364  }
365  }
366  }
367  }
368 end:
369  av_bprint_finalize(&ptstr, NULL);
370  av_file_unmap(buf, size);
371  return ret;
372 }
373 
374 static av_cold int init(AVFilterContext *ctx)
375 {
376  int i, j, ret;
377  CurvesContext *curves = ctx->priv;
378  struct keypoint *comp_points[NB_COMP + 1] = {0};
379  char **pts = curves->comp_points_str;
380  const char *allp = curves->comp_points_str_all;
381 
382  //if (!allp && curves->preset != PRESET_NONE && curves_presets[curves->preset].all)
383  // allp = curves_presets[curves->preset].all;
384 
385  if (allp) {
386  for (i = 0; i < NB_COMP; i++) {
387  if (!pts[i])
388  pts[i] = av_strdup(allp);
389  if (!pts[i])
390  return AVERROR(ENOMEM);
391  }
392  }
393 
394  if (curves->psfile) {
395  ret = parse_psfile(ctx, curves->psfile);
396  if (ret < 0)
397  return ret;
398  }
399 
400  if (curves->preset != PRESET_NONE) {
401 #define SET_COMP_IF_NOT_SET(n, name) do { \
402  if (!pts[n] && curves_presets[curves->preset].name) { \
403  pts[n] = av_strdup(curves_presets[curves->preset].name); \
404  if (!pts[n]) \
405  return AVERROR(ENOMEM); \
406  } \
407 } while (0)
412  }
413 
414  for (i = 0; i < NB_COMP + 1; i++) {
415  ret = parse_points_str(ctx, comp_points + i, curves->comp_points_str[i]);
416  if (ret < 0)
417  return ret;
418  ret = interpolate(ctx, curves->graph[i], comp_points[i]);
419  if (ret < 0)
420  return ret;
421  }
422 
423  if (pts[NB_COMP]) {
424  for (i = 0; i < NB_COMP; i++)
425  for (j = 0; j < 256; j++)
426  curves->graph[i][j] = curves->graph[NB_COMP][curves->graph[i][j]];
427  }
428 
429  if (av_log_get_level() >= AV_LOG_VERBOSE) {
430  for (i = 0; i < NB_COMP; i++) {
431  struct keypoint *point = comp_points[i];
432  av_log(ctx, AV_LOG_VERBOSE, "#%d points:", i);
433  while (point) {
434  av_log(ctx, AV_LOG_VERBOSE, " (%f;%f)", point->x, point->y);
435  point = point->next;
436  }
437  av_log(ctx, AV_LOG_VERBOSE, "\n");
438  av_log(ctx, AV_LOG_VERBOSE, "#%d values:", i);
439  for (j = 0; j < 256; j++)
440  av_log(ctx, AV_LOG_VERBOSE, " %02X", curves->graph[i][j]);
441  av_log(ctx, AV_LOG_VERBOSE, "\n");
442  }
443  }
444 
445  for (i = 0; i < NB_COMP + 1; i++) {
446  struct keypoint *point = comp_points[i];
447  while (point) {
448  struct keypoint *next = point->next;
449  av_free(point);
450  point = next;
451  }
452  }
453 
454  return 0;
455 }
456 
458 {
459  static const enum AVPixelFormat pix_fmts[] = {
466  };
468  return 0;
469 }
470 
471 static int config_input(AVFilterLink *inlink)
472 {
473  CurvesContext *curves = inlink->dst->priv;
474  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
475 
476  ff_fill_rgba_map(curves->rgba_map, inlink->format);
477  curves->step = av_get_padded_bits_per_pixel(desc) >> 3;
478 
479  return 0;
480 }
481 
482 static int filter_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
483 {
484  int x, y;
485  const CurvesContext *curves = ctx->priv;
486  const ThreadData *td = arg;
487  const AVFrame *in = td->in;
488  const AVFrame *out = td->out;
489  const int direct = out == in;
490  const int step = curves->step;
491  const uint8_t r = curves->rgba_map[R];
492  const uint8_t g = curves->rgba_map[G];
493  const uint8_t b = curves->rgba_map[B];
494  const uint8_t a = curves->rgba_map[A];
495  const int slice_start = (in->height * jobnr ) / nb_jobs;
496  const int slice_end = (in->height * (jobnr+1)) / nb_jobs;
497  uint8_t *dst = out->data[0] + slice_start * out->linesize[0];
498  const uint8_t *src = in->data[0] + slice_start * in->linesize[0];
499 
500  for (y = slice_start; y < slice_end; y++) {
501  for (x = 0; x < in->width * step; x += step) {
502  dst[x + r] = curves->graph[R][src[x + r]];
503  dst[x + g] = curves->graph[G][src[x + g]];
504  dst[x + b] = curves->graph[B][src[x + b]];
505  if (!direct && step == 4)
506  dst[x + a] = src[x + a];
507  }
508  dst += out->linesize[0];
509  src += in ->linesize[0];
510  }
511  return 0;
512 }
513 
514 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
515 {
516  AVFilterContext *ctx = inlink->dst;
517  AVFilterLink *outlink = ctx->outputs[0];
518  AVFrame *out;
519  ThreadData td;
520 
521  if (av_frame_is_writable(in)) {
522  out = in;
523  } else {
524  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
525  if (!out) {
526  av_frame_free(&in);
527  return AVERROR(ENOMEM);
528  }
529  av_frame_copy_props(out, in);
530  }
531 
532  td.in = in;
533  td.out = out;
534  ctx->internal->execute(ctx, filter_slice, &td, NULL, FFMIN(outlink->h, ctx->graph->nb_threads));
535 
536  if (out != in)
537  av_frame_free(&in);
538 
539  return ff_filter_frame(outlink, out);
540 }
541 
542 static const AVFilterPad curves_inputs[] = {
543  {
544  .name = "default",
545  .type = AVMEDIA_TYPE_VIDEO,
546  .filter_frame = filter_frame,
547  .config_props = config_input,
548  },
549  { NULL }
550 };
551 
552 static const AVFilterPad curves_outputs[] = {
553  {
554  .name = "default",
555  .type = AVMEDIA_TYPE_VIDEO,
556  },
557  { NULL }
558 };
559 
561  .name = "curves",
562  .description = NULL_IF_CONFIG_SMALL("Adjust components curves."),
563  .priv_size = sizeof(CurvesContext),
564  .init = init,
566  .inputs = curves_inputs,
567  .outputs = curves_outputs,
568  .priv_class = &curves_class,
570 };