vf_lut.c
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1 /*
2  * Copyright (c) 2011 Stefano Sabatini
3  *
4  * This file is part of Libav.
5  *
6  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
27 #include "libavutil/eval.h"
28 #include "libavutil/mathematics.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/pixdesc.h"
31 #include "avfilter.h"
32 #include "internal.h"
33 
34 static const char *var_names[] = {
35  "E",
36  "PHI",
37  "PI",
38  "w",
39  "h",
40  "val",
41  "maxval",
42  "minval",
43  "negval",
44  "clipval",
45  NULL
46 };
47 
48 enum var_name {
60 };
61 
62 typedef struct {
63  const AVClass *class;
64  uint8_t lut[4][256];
65  char *comp_expr_str[4];
66  AVExpr *comp_expr[4];
67  int hsub, vsub;
68  double var_values[VAR_VARS_NB];
69  int is_rgb, is_yuv;
70  int rgba_map[4];
71  int step;
72  int negate_alpha; /* only used by negate */
73 } LutContext;
74 
75 #define Y 0
76 #define U 1
77 #define V 2
78 #define R 0
79 #define G 1
80 #define B 2
81 #define A 3
82 
83 #define OFFSET(x) offsetof(LutContext, x)
84 
85 static const AVOption lut_options[] = {
86  {"c0", "set component #0 expression", OFFSET(comp_expr_str[0]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
87  {"c1", "set component #1 expression", OFFSET(comp_expr_str[1]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
88  {"c2", "set component #2 expression", OFFSET(comp_expr_str[2]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
89  {"c3", "set component #3 expression", OFFSET(comp_expr_str[3]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
90  {"y", "set Y expression", OFFSET(comp_expr_str[Y]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
91  {"u", "set U expression", OFFSET(comp_expr_str[U]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
92  {"v", "set V expression", OFFSET(comp_expr_str[V]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
93  {"r", "set R expression", OFFSET(comp_expr_str[R]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
94  {"g", "set G expression", OFFSET(comp_expr_str[G]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
95  {"b", "set B expression", OFFSET(comp_expr_str[B]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
96  {"a", "set A expression", OFFSET(comp_expr_str[A]), FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
97  {NULL},
98 };
99 
100 static const char *lut_get_name(void *ctx)
101 {
102  return "lut";
103 }
104 
105 static const AVClass lut_class = {
106  "LutContext",
107  lut_get_name,
108  lut_options
109 };
110 
111 static int init(AVFilterContext *ctx, const char *args, void *opaque)
112 {
113  LutContext *lut = ctx->priv;
114  int ret;
115 
116  lut->class = &lut_class;
117  av_opt_set_defaults(lut);
118 
119  lut->var_values[VAR_PHI] = M_PHI;
120  lut->var_values[VAR_PI] = M_PI;
121  lut->var_values[VAR_E ] = M_E;
122 
123  lut->is_rgb = !strcmp(ctx->filter->name, "lutrgb");
124  lut->is_yuv = !strcmp(ctx->filter->name, "lutyuv");
125  if (args && (ret = av_set_options_string(lut, args, "=", ":")) < 0)
126  return ret;
127 
128  return 0;
129 }
130 
131 static av_cold void uninit(AVFilterContext *ctx)
132 {
133  LutContext *lut = ctx->priv;
134  int i;
135 
136  for (i = 0; i < 4; i++) {
137  av_expr_free(lut->comp_expr[i]);
138  lut->comp_expr[i] = NULL;
139  av_freep(&lut->comp_expr_str[i]);
140  }
141 }
142 
143 #define YUV_FORMATS \
144  PIX_FMT_YUV444P, PIX_FMT_YUV422P, PIX_FMT_YUV420P, \
145  PIX_FMT_YUV411P, PIX_FMT_YUV410P, PIX_FMT_YUV440P, \
146  PIX_FMT_YUVA420P, \
147  PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P, \
148  PIX_FMT_YUVJ440P
149 
150 #define RGB_FORMATS \
151  PIX_FMT_ARGB, PIX_FMT_RGBA, \
152  PIX_FMT_ABGR, PIX_FMT_BGRA, \
153  PIX_FMT_RGB24, PIX_FMT_BGR24
154 
158 
160 {
161  LutContext *lut = ctx->priv;
162 
163  enum PixelFormat *pix_fmts = lut->is_rgb ? rgb_pix_fmts :
165 
167  return 0;
168 }
169 
173 static double clip(void *opaque, double val)
174 {
175  LutContext *lut = opaque;
176  double minval = lut->var_values[VAR_MINVAL];
177  double maxval = lut->var_values[VAR_MAXVAL];
178 
179  return av_clip(val, minval, maxval);
180 }
181 
186 static double compute_gammaval(void *opaque, double gamma)
187 {
188  LutContext *lut = opaque;
189  double val = lut->var_values[VAR_CLIPVAL];
190  double minval = lut->var_values[VAR_MINVAL];
191  double maxval = lut->var_values[VAR_MAXVAL];
192 
193  return pow((val-minval)/(maxval-minval), gamma) * (maxval-minval)+minval;
194 }
195 
196 static double (* const funcs1[])(void *, double) = {
197  clip,
199  NULL
200 };
201 
202 static const char * const funcs1_names[] = {
203  "clip",
204  "gammaval",
205  NULL
206 };
207 
208 static int config_props(AVFilterLink *inlink)
209 {
210  AVFilterContext *ctx = inlink->dst;
211  LutContext *lut = ctx->priv;
212  const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[inlink->format];
213  int min[4], max[4];
214  int val, comp, ret;
215 
216  lut->hsub = desc->log2_chroma_w;
217  lut->vsub = desc->log2_chroma_h;
218 
219  lut->var_values[VAR_W] = inlink->w;
220  lut->var_values[VAR_H] = inlink->h;
221 
222  switch (inlink->format) {
223  case PIX_FMT_YUV410P:
224  case PIX_FMT_YUV411P:
225  case PIX_FMT_YUV420P:
226  case PIX_FMT_YUV422P:
227  case PIX_FMT_YUV440P:
228  case PIX_FMT_YUV444P:
229  case PIX_FMT_YUVA420P:
230  min[Y] = min[U] = min[V] = 16;
231  max[Y] = 235;
232  max[U] = max[V] = 240;
233  min[A] = 0; max[A] = 255;
234  break;
235  default:
236  min[0] = min[1] = min[2] = min[3] = 0;
237  max[0] = max[1] = max[2] = max[3] = 255;
238  }
239 
240  lut->is_yuv = lut->is_rgb = 0;
241  if (ff_fmt_is_in(inlink->format, yuv_pix_fmts)) lut->is_yuv = 1;
242  else if (ff_fmt_is_in(inlink->format, rgb_pix_fmts)) lut->is_rgb = 1;
243 
244  if (lut->is_rgb) {
245  switch (inlink->format) {
246  case PIX_FMT_ARGB: lut->rgba_map[A] = 0; lut->rgba_map[R] = 1; lut->rgba_map[G] = 2; lut->rgba_map[B] = 3; break;
247  case PIX_FMT_ABGR: lut->rgba_map[A] = 0; lut->rgba_map[B] = 1; lut->rgba_map[G] = 2; lut->rgba_map[R] = 3; break;
248  case PIX_FMT_RGBA:
249  case PIX_FMT_RGB24: lut->rgba_map[R] = 0; lut->rgba_map[G] = 1; lut->rgba_map[B] = 2; lut->rgba_map[A] = 3; break;
250  case PIX_FMT_BGRA:
251  case PIX_FMT_BGR24: lut->rgba_map[B] = 0; lut->rgba_map[G] = 1; lut->rgba_map[R] = 2; lut->rgba_map[A] = 3; break;
252  }
253  lut->step = av_get_bits_per_pixel(desc) >> 3;
254  }
255 
256  for (comp = 0; comp < desc->nb_components; comp++) {
257  double res;
258 
259  /* create the parsed expression */
260  ret = av_expr_parse(&lut->comp_expr[comp], lut->comp_expr_str[comp],
261  var_names, funcs1_names, funcs1, NULL, NULL, 0, ctx);
262  if (ret < 0) {
263  av_log(ctx, AV_LOG_ERROR,
264  "Error when parsing the expression '%s' for the component %d.\n",
265  lut->comp_expr_str[comp], comp);
266  return AVERROR(EINVAL);
267  }
268 
269  /* compute the lut */
270  lut->var_values[VAR_MAXVAL] = max[comp];
271  lut->var_values[VAR_MINVAL] = min[comp];
272 
273  for (val = 0; val < 256; val++) {
274  lut->var_values[VAR_VAL] = val;
275  lut->var_values[VAR_CLIPVAL] = av_clip(val, min[comp], max[comp]);
276  lut->var_values[VAR_NEGVAL] =
277  av_clip(min[comp] + max[comp] - lut->var_values[VAR_VAL],
278  min[comp], max[comp]);
279 
280  res = av_expr_eval(lut->comp_expr[comp], lut->var_values, lut);
281  if (isnan(res)) {
282  av_log(ctx, AV_LOG_ERROR,
283  "Error when evaluating the expression '%s' for the value %d for the component #%d.\n",
284  lut->comp_expr_str[comp], val, comp);
285  return AVERROR(EINVAL);
286  }
287  lut->lut[comp][val] = av_clip((int)res, min[comp], max[comp]);
288  av_log(ctx, AV_LOG_DEBUG, "val[%d][%d] = %d\n", comp, val, lut->lut[comp][val]);
289  }
290  }
291 
292  return 0;
293 }
294 
295 static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
296 {
297  AVFilterContext *ctx = inlink->dst;
298  LutContext *lut = ctx->priv;
299  AVFilterLink *outlink = ctx->outputs[0];
300  AVFilterBufferRef *inpic = inlink ->cur_buf;
301  AVFilterBufferRef *outpic = outlink->out_buf;
302  uint8_t *inrow, *outrow, *inrow0, *outrow0;
303  int i, j, k, plane;
304 
305  if (lut->is_rgb) {
306  /* packed */
307  inrow0 = inpic ->data[0] + y * inpic ->linesize[0];
308  outrow0 = outpic->data[0] + y * outpic->linesize[0];
309 
310  for (i = 0; i < h; i ++) {
311  inrow = inrow0;
312  outrow = outrow0;
313  for (j = 0; j < inlink->w; j++) {
314  for (k = 0; k < lut->step; k++)
315  outrow[k] = lut->lut[lut->rgba_map[k]][inrow[k]];
316  outrow += lut->step;
317  inrow += lut->step;
318  }
319  inrow0 += inpic ->linesize[0];
320  outrow0 += outpic->linesize[0];
321  }
322  } else {
323  /* planar */
324  for (plane = 0; plane < 4 && inpic->data[plane]; plane++) {
325  int vsub = plane == 1 || plane == 2 ? lut->vsub : 0;
326  int hsub = plane == 1 || plane == 2 ? lut->hsub : 0;
327 
328  inrow = inpic ->data[plane] + (y>>vsub) * inpic ->linesize[plane];
329  outrow = outpic->data[plane] + (y>>vsub) * outpic->linesize[plane];
330 
331  for (i = 0; i < h>>vsub; i ++) {
332  for (j = 0; j < inlink->w>>hsub; j++)
333  outrow[j] = lut->lut[plane][inrow[j]];
334  inrow += inpic ->linesize[plane];
335  outrow += outpic->linesize[plane];
336  }
337  }
338  }
339 
340  avfilter_draw_slice(outlink, y, h, slice_dir);
341 }
342 
343 #define DEFINE_LUT_FILTER(name_, description_, init_) \
344  AVFilter avfilter_vf_##name_ = { \
345  .name = #name_, \
346  .description = NULL_IF_CONFIG_SMALL(description_), \
347  .priv_size = sizeof(LutContext), \
348  \
349  .init = init_, \
350  .uninit = uninit, \
351  .query_formats = query_formats, \
352  \
353  .inputs = (AVFilterPad[]) {{ .name = "default", \
354  .type = AVMEDIA_TYPE_VIDEO, \
355  .draw_slice = draw_slice, \
356  .config_props = config_props, \
357  .min_perms = AV_PERM_READ, }, \
358  { .name = NULL}}, \
359  .outputs = (AVFilterPad[]) {{ .name = "default", \
360  .type = AVMEDIA_TYPE_VIDEO, }, \
361  { .name = NULL}}, \
362  }
363 
364 #if CONFIG_LUT_FILTER
365 DEFINE_LUT_FILTER(lut, "Compute and apply a lookup table to the RGB/YUV input video.", init);
366 #endif
367 #if CONFIG_LUTYUV_FILTER
368 DEFINE_LUT_FILTER(lutyuv, "Compute and apply a lookup table to the YUV input video.", init);
369 #endif
370 #if CONFIG_LUTRGB_FILTER
371 DEFINE_LUT_FILTER(lutrgb, "Compute and apply a lookup table to the RGB input video.", init);
372 #endif
373 
374 #if CONFIG_NEGATE_FILTER
375 
376 static int negate_init(AVFilterContext *ctx, const char *args, void *opaque)
377 {
378  LutContext *lut = ctx->priv;
379  char lut_params[64];
380 
381  if (args)
382  sscanf(args, "%d", &lut->negate_alpha);
383 
384  av_log(ctx, AV_LOG_DEBUG, "negate_alpha:%d\n", lut->negate_alpha);
385 
386  snprintf(lut_params, sizeof(lut_params), "c0=negval:c1=negval:c2=negval:a=%s",
387  lut->negate_alpha ? "negval" : "val");
388 
389  return init(ctx, lut_params, opaque);
390 }
391 
392 DEFINE_LUT_FILTER(negate, "Negate input video.", negate_init);
393 
394 #endif