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path: root/libavfilter/vf_lut.c (plain)
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1/*
2 * Copyright (c) 2011 Stefano Sabatini
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/**
22 * @file
23 * Compute a look-up table for binding the input value to the output
24 * value, and apply it to input video.
25 */
26
27#include "libavutil/attributes.h"
28#include "libavutil/bswap.h"
29#include "libavutil/common.h"
30#include "libavutil/eval.h"
31#include "libavutil/opt.h"
32#include "libavutil/pixdesc.h"
33#include "avfilter.h"
34#include "drawutils.h"
35#include "formats.h"
36#include "internal.h"
37#include "video.h"
38
39static const char *const var_names[] = {
40 "w", ///< width of the input video
41 "h", ///< height of the input video
42 "val", ///< input value for the pixel
43 "maxval", ///< max value for the pixel
44 "minval", ///< min value for the pixel
45 "negval", ///< negated value
46 "clipval",
47 NULL
48};
49
50enum var_name {
51 VAR_W,
52 VAR_H,
53 VAR_VAL,
54 VAR_MAXVAL,
55 VAR_MINVAL,
56 VAR_NEGVAL,
57 VAR_CLIPVAL,
58 VAR_VARS_NB
59};
60
61typedef struct LutContext {
62 const AVClass *class;
63 uint16_t lut[4][256 * 256]; ///< lookup table for each component
64 char *comp_expr_str[4];
65 AVExpr *comp_expr[4];
66 int hsub, vsub;
67 double var_values[VAR_VARS_NB];
68 int is_rgb, is_yuv;
69 int is_planar;
70 int is_16bit;
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#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
85
86static const AVOption options[] = {
87 { "c0", "set component #0 expression", OFFSET(comp_expr_str[0]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
88 { "c1", "set component #1 expression", OFFSET(comp_expr_str[1]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
89 { "c2", "set component #2 expression", OFFSET(comp_expr_str[2]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
90 { "c3", "set component #3 expression", OFFSET(comp_expr_str[3]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
91 { "y", "set Y expression", OFFSET(comp_expr_str[Y]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
92 { "u", "set U expression", OFFSET(comp_expr_str[U]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
93 { "v", "set V expression", OFFSET(comp_expr_str[V]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
94 { "r", "set R expression", OFFSET(comp_expr_str[R]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
95 { "g", "set G expression", OFFSET(comp_expr_str[G]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
96 { "b", "set B expression", OFFSET(comp_expr_str[B]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
97 { "a", "set A expression", OFFSET(comp_expr_str[A]), AV_OPT_TYPE_STRING, { .str = "clipval" }, .flags = FLAGS },
98 { NULL }
99};
100
101static av_cold void uninit(AVFilterContext *ctx)
102{
103 LutContext *s = ctx->priv;
104 int i;
105
106 for (i = 0; i < 4; i++) {
107 av_expr_free(s->comp_expr[i]);
108 s->comp_expr[i] = NULL;
109 av_freep(&s->comp_expr_str[i]);
110 }
111}
112
113#define YUV_FORMATS \
114 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV420P, \
115 AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV440P, \
116 AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P, \
117 AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P, \
118 AV_PIX_FMT_YUVJ440P, \
119 AV_PIX_FMT_YUV444P9LE, AV_PIX_FMT_YUV422P9LE, AV_PIX_FMT_YUV420P9LE, \
120 AV_PIX_FMT_YUV444P10LE, AV_PIX_FMT_YUV422P10LE, AV_PIX_FMT_YUV420P10LE, AV_PIX_FMT_YUV440P10LE, \
121 AV_PIX_FMT_YUV444P12LE, AV_PIX_FMT_YUV422P12LE, AV_PIX_FMT_YUV420P12LE, AV_PIX_FMT_YUV440P12LE, \
122 AV_PIX_FMT_YUV444P14LE, AV_PIX_FMT_YUV422P14LE, AV_PIX_FMT_YUV420P14LE, \
123 AV_PIX_FMT_YUV444P16LE, AV_PIX_FMT_YUV422P16LE, AV_PIX_FMT_YUV420P16LE, \
124 AV_PIX_FMT_YUVA444P16LE, AV_PIX_FMT_YUVA422P16LE, AV_PIX_FMT_YUVA420P16LE
125
126#define RGB_FORMATS \
127 AV_PIX_FMT_ARGB, AV_PIX_FMT_RGBA, \
128 AV_PIX_FMT_ABGR, AV_PIX_FMT_BGRA, \
129 AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24, \
130 AV_PIX_FMT_RGB48LE, AV_PIX_FMT_RGBA64LE, \
131 AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP, \
132 AV_PIX_FMT_GBRP9LE, AV_PIX_FMT_GBRP10LE, \
133 AV_PIX_FMT_GBRP12LE, AV_PIX_FMT_GBRP14LE, \
134 AV_PIX_FMT_GBRP16LE, AV_PIX_FMT_GBRAP12LE, \
135 AV_PIX_FMT_GBRAP16LE
136
137static const enum AVPixelFormat yuv_pix_fmts[] = { YUV_FORMATS, AV_PIX_FMT_NONE };
138static const enum AVPixelFormat rgb_pix_fmts[] = { RGB_FORMATS, AV_PIX_FMT_NONE };
139static const enum AVPixelFormat all_pix_fmts[] = { RGB_FORMATS, YUV_FORMATS, AV_PIX_FMT_NONE };
140
141static int query_formats(AVFilterContext *ctx)
142{
143 LutContext *s = ctx->priv;
144
145 const enum AVPixelFormat *pix_fmts = s->is_rgb ? rgb_pix_fmts :
146 s->is_yuv ? yuv_pix_fmts :
147 all_pix_fmts;
148 AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
149 if (!fmts_list)
150 return AVERROR(ENOMEM);
151 return ff_set_common_formats(ctx, fmts_list);
152}
153
154/**
155 * Clip value val in the minval - maxval range.
156 */
157static double clip(void *opaque, double val)
158{
159 LutContext *s = opaque;
160 double minval = s->var_values[VAR_MINVAL];
161 double maxval = s->var_values[VAR_MAXVAL];
162
163 return av_clip(val, minval, maxval);
164}
165
166/**
167 * Compute gamma correction for value val, assuming the minval-maxval
168 * range, val is clipped to a value contained in the same interval.
169 */
170static double compute_gammaval(void *opaque, double gamma)
171{
172 LutContext *s = opaque;
173 double val = s->var_values[VAR_CLIPVAL];
174 double minval = s->var_values[VAR_MINVAL];
175 double maxval = s->var_values[VAR_MAXVAL];
176
177 return pow((val-minval)/(maxval-minval), gamma) * (maxval-minval)+minval;
178}
179
180/**
181 * Compute ITU Rec.709 gamma correction of value val.
182 */
183static double compute_gammaval709(void *opaque, double gamma)
184{
185 LutContext *s = opaque;
186 double val = s->var_values[VAR_CLIPVAL];
187 double minval = s->var_values[VAR_MINVAL];
188 double maxval = s->var_values[VAR_MAXVAL];
189 double level = (val - minval) / (maxval - minval);
190 level = level < 0.018 ? 4.5 * level
191 : 1.099 * pow(level, 1.0 / gamma) - 0.099;
192 return level * (maxval - minval) + minval;
193}
194
195static double (* const funcs1[])(void *, double) = {
196 clip,
197 compute_gammaval,
198 compute_gammaval709,
199 NULL
200};
201
202static const char * const funcs1_names[] = {
203 "clip",
204 "gammaval",
205 "gammaval709",
206 NULL
207};
208
209static int config_props(AVFilterLink *inlink)
210{
211 AVFilterContext *ctx = inlink->dst;
212 LutContext *s = ctx->priv;
213 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
214 uint8_t rgba_map[4]; /* component index -> RGBA color index map */
215 int min[4], max[4];
216 int val, color, ret;
217
218 s->hsub = desc->log2_chroma_w;
219 s->vsub = desc->log2_chroma_h;
220
221 s->var_values[VAR_W] = inlink->w;
222 s->var_values[VAR_H] = inlink->h;
223 s->is_16bit = desc->comp[0].depth > 8;
224
225 switch (inlink->format) {
226 case AV_PIX_FMT_YUV410P:
227 case AV_PIX_FMT_YUV411P:
228 case AV_PIX_FMT_YUV420P:
229 case AV_PIX_FMT_YUV422P:
230 case AV_PIX_FMT_YUV440P:
231 case AV_PIX_FMT_YUV444P:
232 case AV_PIX_FMT_YUVA420P:
233 case AV_PIX_FMT_YUVA422P:
234 case AV_PIX_FMT_YUVA444P:
235 case AV_PIX_FMT_YUV420P9LE:
236 case AV_PIX_FMT_YUV422P9LE:
237 case AV_PIX_FMT_YUV444P9LE:
238 case AV_PIX_FMT_YUVA420P9LE:
239 case AV_PIX_FMT_YUVA422P9LE:
240 case AV_PIX_FMT_YUVA444P9LE:
241 case AV_PIX_FMT_YUV420P10LE:
242 case AV_PIX_FMT_YUV422P10LE:
243 case AV_PIX_FMT_YUV440P10LE:
244 case AV_PIX_FMT_YUV444P10LE:
245 case AV_PIX_FMT_YUVA420P10LE:
246 case AV_PIX_FMT_YUVA422P10LE:
247 case AV_PIX_FMT_YUVA444P10LE:
248 case AV_PIX_FMT_YUV420P12LE:
249 case AV_PIX_FMT_YUV422P12LE:
250 case AV_PIX_FMT_YUV440P12LE:
251 case AV_PIX_FMT_YUV444P12LE:
252 case AV_PIX_FMT_YUV420P14LE:
253 case AV_PIX_FMT_YUV422P14LE:
254 case AV_PIX_FMT_YUV444P14LE:
255 case AV_PIX_FMT_YUV420P16LE:
256 case AV_PIX_FMT_YUV422P16LE:
257 case AV_PIX_FMT_YUV444P16LE:
258 case AV_PIX_FMT_YUVA420P16LE:
259 case AV_PIX_FMT_YUVA422P16LE:
260 case AV_PIX_FMT_YUVA444P16LE:
261 min[Y] = 16 * (1 << (desc->comp[0].depth - 8));
262 min[U] = 16 * (1 << (desc->comp[1].depth - 8));
263 min[V] = 16 * (1 << (desc->comp[2].depth - 8));
264 min[A] = 0;
265 max[Y] = 235 * (1 << (desc->comp[0].depth - 8));
266 max[U] = 240 * (1 << (desc->comp[1].depth - 8));
267 max[V] = 240 * (1 << (desc->comp[2].depth - 8));
268 max[A] = (1 << desc->comp[0].depth) - 1;
269 break;
270 case AV_PIX_FMT_RGB48LE:
271 case AV_PIX_FMT_RGBA64LE:
272 min[0] = min[1] = min[2] = min[3] = 0;
273 max[0] = max[1] = max[2] = max[3] = 65535;
274 break;
275 default:
276 min[0] = min[1] = min[2] = min[3] = 0;
277 max[0] = max[1] = max[2] = max[3] = 255 * (1 << (desc->comp[0].depth - 8));
278 }
279
280 s->is_yuv = s->is_rgb = 0;
281 s->is_planar = desc->flags & AV_PIX_FMT_FLAG_PLANAR;
282 if (ff_fmt_is_in(inlink->format, yuv_pix_fmts)) s->is_yuv = 1;
283 else if (ff_fmt_is_in(inlink->format, rgb_pix_fmts)) s->is_rgb = 1;
284
285 if (s->is_rgb) {
286 ff_fill_rgba_map(rgba_map, inlink->format);
287 s->step = av_get_bits_per_pixel(desc) >> 3;
288 if (s->is_16bit) {
289 s->step = s->step >> 1;
290 }
291 }
292
293 for (color = 0; color < desc->nb_components; color++) {
294 double res;
295 int comp = s->is_rgb ? rgba_map[color] : color;
296
297 /* create the parsed expression */
298 av_expr_free(s->comp_expr[color]);
299 s->comp_expr[color] = NULL;
300 ret = av_expr_parse(&s->comp_expr[color], s->comp_expr_str[color],
301 var_names, funcs1_names, funcs1, NULL, NULL, 0, ctx);
302 if (ret < 0) {
303 av_log(ctx, AV_LOG_ERROR,
304 "Error when parsing the expression '%s' for the component %d and color %d.\n",
305 s->comp_expr_str[comp], comp, color);
306 return AVERROR(EINVAL);
307 }
308
309 /* compute the lut */
310 s->var_values[VAR_MAXVAL] = max[color];
311 s->var_values[VAR_MINVAL] = min[color];
312
313 for (val = 0; val < FF_ARRAY_ELEMS(s->lut[comp]); val++) {
314 s->var_values[VAR_VAL] = val;
315 s->var_values[VAR_CLIPVAL] = av_clip(val, min[color], max[color]);
316 s->var_values[VAR_NEGVAL] =
317 av_clip(min[color] + max[color] - s->var_values[VAR_VAL],
318 min[color], max[color]);
319
320 res = av_expr_eval(s->comp_expr[color], s->var_values, s);
321 if (isnan(res)) {
322 av_log(ctx, AV_LOG_ERROR,
323 "Error when evaluating the expression '%s' for the value %d for the component %d.\n",
324 s->comp_expr_str[color], val, comp);
325 return AVERROR(EINVAL);
326 }
327 s->lut[comp][val] = av_clip((int)res, 0, max[A]);
328 av_log(ctx, AV_LOG_DEBUG, "val[%d][%d] = %d\n", comp, val, s->lut[comp][val]);
329 }
330 }
331
332 return 0;
333}
334
335static int filter_frame(AVFilterLink *inlink, AVFrame *in)
336{
337 AVFilterContext *ctx = inlink->dst;
338 LutContext *s = ctx->priv;
339 AVFilterLink *outlink = ctx->outputs[0];
340 AVFrame *out;
341 int i, j, plane, direct = 0;
342
343 if (av_frame_is_writable(in)) {
344 direct = 1;
345 out = in;
346 } else {
347 out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
348 if (!out) {
349 av_frame_free(&in);
350 return AVERROR(ENOMEM);
351 }
352 av_frame_copy_props(out, in);
353 }
354
355 if (s->is_rgb && s->is_16bit && !s->is_planar) {
356 /* packed, 16-bit */
357 uint16_t *inrow, *outrow, *inrow0, *outrow0;
358 const int w = inlink->w;
359 const int h = in->height;
360 const uint16_t (*tab)[256*256] = (const uint16_t (*)[256*256])s->lut;
361 const int in_linesize = in->linesize[0] / 2;
362 const int out_linesize = out->linesize[0] / 2;
363 const int step = s->step;
364
365 inrow0 = (uint16_t*) in ->data[0];
366 outrow0 = (uint16_t*) out->data[0];
367
368 for (i = 0; i < h; i ++) {
369 inrow = inrow0;
370 outrow = outrow0;
371 for (j = 0; j < w; j++) {
372
373 switch (step) {
374#if HAVE_BIGENDIAN
375 case 4: outrow[3] = av_bswap16(tab[3][av_bswap16(inrow[3])]); // Fall-through
376 case 3: outrow[2] = av_bswap16(tab[2][av_bswap16(inrow[2])]); // Fall-through
377 case 2: outrow[1] = av_bswap16(tab[1][av_bswap16(inrow[1])]); // Fall-through
378 default: outrow[0] = av_bswap16(tab[0][av_bswap16(inrow[0])]);
379#else
380 case 4: outrow[3] = tab[3][inrow[3]]; // Fall-through
381 case 3: outrow[2] = tab[2][inrow[2]]; // Fall-through
382 case 2: outrow[1] = tab[1][inrow[1]]; // Fall-through
383 default: outrow[0] = tab[0][inrow[0]];
384#endif
385 }
386 outrow += step;
387 inrow += step;
388 }
389 inrow0 += in_linesize;
390 outrow0 += out_linesize;
391 }
392 } else if (s->is_rgb && !s->is_planar) {
393 /* packed */
394 uint8_t *inrow, *outrow, *inrow0, *outrow0;
395 const int w = inlink->w;
396 const int h = in->height;
397 const uint16_t (*tab)[256*256] = (const uint16_t (*)[256*256])s->lut;
398 const int in_linesize = in->linesize[0];
399 const int out_linesize = out->linesize[0];
400 const int step = s->step;
401
402 inrow0 = in ->data[0];
403 outrow0 = out->data[0];
404
405 for (i = 0; i < h; i ++) {
406 inrow = inrow0;
407 outrow = outrow0;
408 for (j = 0; j < w; j++) {
409 switch (step) {
410 case 4: outrow[3] = tab[3][inrow[3]]; // Fall-through
411 case 3: outrow[2] = tab[2][inrow[2]]; // Fall-through
412 case 2: outrow[1] = tab[1][inrow[1]]; // Fall-through
413 default: outrow[0] = tab[0][inrow[0]];
414 }
415 outrow += step;
416 inrow += step;
417 }
418 inrow0 += in_linesize;
419 outrow0 += out_linesize;
420 }
421 } else if (s->is_16bit) {
422 // planar >8 bit depth
423 uint16_t *inrow, *outrow;
424
425 for (plane = 0; plane < 4 && in->data[plane] && in->linesize[plane]; plane++) {
426 int vsub = plane == 1 || plane == 2 ? s->vsub : 0;
427 int hsub = plane == 1 || plane == 2 ? s->hsub : 0;
428 int h = AV_CEIL_RSHIFT(inlink->h, vsub);
429 int w = AV_CEIL_RSHIFT(inlink->w, hsub);
430 const uint16_t *tab = s->lut[plane];
431 const int in_linesize = in->linesize[plane] / 2;
432 const int out_linesize = out->linesize[plane] / 2;
433
434 inrow = (uint16_t *)in ->data[plane];
435 outrow = (uint16_t *)out->data[plane];
436
437 for (i = 0; i < h; i++) {
438 for (j = 0; j < w; j++) {
439#if HAVE_BIGENDIAN
440 outrow[j] = av_bswap16(tab[av_bswap16(inrow[j])]);
441#else
442 outrow[j] = tab[inrow[j]];
443#endif
444 }
445 inrow += in_linesize;
446 outrow += out_linesize;
447 }
448 }
449 } else {
450 /* planar 8bit depth */
451 uint8_t *inrow, *outrow;
452
453 for (plane = 0; plane < 4 && in->data[plane] && in->linesize[plane]; plane++) {
454 int vsub = plane == 1 || plane == 2 ? s->vsub : 0;
455 int hsub = plane == 1 || plane == 2 ? s->hsub : 0;
456 int h = AV_CEIL_RSHIFT(inlink->h, vsub);
457 int w = AV_CEIL_RSHIFT(inlink->w, hsub);
458 const uint16_t *tab = s->lut[plane];
459 const int in_linesize = in->linesize[plane];
460 const int out_linesize = out->linesize[plane];
461
462 inrow = in ->data[plane];
463 outrow = out->data[plane];
464
465 for (i = 0; i < h; i++) {
466 for (j = 0; j < w; j++)
467 outrow[j] = tab[inrow[j]];
468 inrow += in_linesize;
469 outrow += out_linesize;
470 }
471 }
472 }
473
474 if (!direct)
475 av_frame_free(&in);
476
477 return ff_filter_frame(outlink, out);
478}
479
480static const AVFilterPad inputs[] = {
481 { .name = "default",
482 .type = AVMEDIA_TYPE_VIDEO,
483 .filter_frame = filter_frame,
484 .config_props = config_props,
485 },
486 { NULL }
487};
488static const AVFilterPad outputs[] = {
489 { .name = "default",
490 .type = AVMEDIA_TYPE_VIDEO,
491 },
492 { NULL }
493};
494
495#define DEFINE_LUT_FILTER(name_, description_) \
496 AVFilter ff_vf_##name_ = { \
497 .name = #name_, \
498 .description = NULL_IF_CONFIG_SMALL(description_), \
499 .priv_size = sizeof(LutContext), \
500 .priv_class = &name_ ## _class, \
501 .init = name_##_init, \
502 .uninit = uninit, \
503 .query_formats = query_formats, \
504 .inputs = inputs, \
505 .outputs = outputs, \
506 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, \
507 }
508
509#if CONFIG_LUT_FILTER
510
511#define lut_options options
512AVFILTER_DEFINE_CLASS(lut);
513
514static int lut_init(AVFilterContext *ctx)
515{
516 return 0;
517}
518
519DEFINE_LUT_FILTER(lut, "Compute and apply a lookup table to the RGB/YUV input video.");
520#endif
521
522#if CONFIG_LUTYUV_FILTER
523
524#define lutyuv_options options
525AVFILTER_DEFINE_CLASS(lutyuv);
526
527static av_cold int lutyuv_init(AVFilterContext *ctx)
528{
529 LutContext *s = ctx->priv;
530
531 s->is_yuv = 1;
532
533 return 0;
534}
535
536DEFINE_LUT_FILTER(lutyuv, "Compute and apply a lookup table to the YUV input video.");
537#endif
538
539#if CONFIG_LUTRGB_FILTER
540
541#define lutrgb_options options
542AVFILTER_DEFINE_CLASS(lutrgb);
543
544static av_cold int lutrgb_init(AVFilterContext *ctx)
545{
546 LutContext *s = ctx->priv;
547
548 s->is_rgb = 1;
549
550 return 0;
551}
552
553DEFINE_LUT_FILTER(lutrgb, "Compute and apply a lookup table to the RGB input video.");
554#endif
555
556#if CONFIG_NEGATE_FILTER
557
558static const AVOption negate_options[] = {
559 { "negate_alpha", NULL, OFFSET(negate_alpha), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },
560 { NULL }
561};
562
563AVFILTER_DEFINE_CLASS(negate);
564
565static av_cold int negate_init(AVFilterContext *ctx)
566{
567 LutContext *s = ctx->priv;
568 int i;
569
570 av_log(ctx, AV_LOG_DEBUG, "negate_alpha:%d\n", s->negate_alpha);
571
572 for (i = 0; i < 4; i++) {
573 s->comp_expr_str[i] = av_strdup((i == 3 && !s->negate_alpha) ?
574 "val" : "negval");
575 if (!s->comp_expr_str[i]) {
576 uninit(ctx);
577 return AVERROR(ENOMEM);
578 }
579 }
580
581 return 0;
582}
583
584DEFINE_LUT_FILTER(negate, "Negate input video.");
585
586#endif
587
generated by cgit at 2024-05-17 03:08:24 (GMT)