2 * Copyright (c) 2011 Stefano Sabatini
4 * This file is part of Libav.
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.
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.
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
23 * Compute a look-up table for binding the input value to the output
24 * value, and apply it to input video.
27 #include "libavutil/common.h"
28 #include "libavutil/eval.h"
29 #include "libavutil/mathematics.h"
30 #include "libavutil/opt.h"
31 #include "libavutil/pixdesc.h"
37 static const char *const var_names[] = {
41 "w", ///< width of the input video
42 "h", ///< height of the input video
43 "val", ///< input value for the pixel
44 "maxval", ///< max value for the pixel
45 "minval", ///< min value for the pixel
46 "negval", ///< negated value
67 uint8_t lut[4][256]; ///< lookup table for each component
68 char *comp_expr_str[4];
71 double var_values[VAR_VARS_NB];
75 int negate_alpha; /* only used by negate */
86 #define OFFSET(x) offsetof(LutContext, x)
88 static const AVOption lut_options[] = {
89 {"c0", "set component #0 expression", OFFSET(comp_expr_str[0]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
90 {"c1", "set component #1 expression", OFFSET(comp_expr_str[1]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
91 {"c2", "set component #2 expression", OFFSET(comp_expr_str[2]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
92 {"c3", "set component #3 expression", OFFSET(comp_expr_str[3]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
93 {"y", "set Y expression", OFFSET(comp_expr_str[Y]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
94 {"u", "set U expression", OFFSET(comp_expr_str[U]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
95 {"v", "set V expression", OFFSET(comp_expr_str[V]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
96 {"r", "set R expression", OFFSET(comp_expr_str[R]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
97 {"g", "set G expression", OFFSET(comp_expr_str[G]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
98 {"b", "set B expression", OFFSET(comp_expr_str[B]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
99 {"a", "set A expression", OFFSET(comp_expr_str[A]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
103 static const char *lut_get_name(void *ctx)
108 static const AVClass lut_class = {
114 static int init(AVFilterContext *ctx, const char *args)
116 LutContext *lut = ctx->priv;
119 lut->class = &lut_class;
120 av_opt_set_defaults(lut);
122 lut->var_values[VAR_PHI] = M_PHI;
123 lut->var_values[VAR_PI] = M_PI;
124 lut->var_values[VAR_E ] = M_E;
126 lut->is_rgb = !strcmp(ctx->filter->name, "lutrgb");
127 lut->is_yuv = !strcmp(ctx->filter->name, "lutyuv");
128 if (args && (ret = av_set_options_string(lut, args, "=", ":")) < 0)
134 static av_cold void uninit(AVFilterContext *ctx)
136 LutContext *lut = ctx->priv;
139 for (i = 0; i < 4; i++) {
140 av_expr_free(lut->comp_expr[i]);
141 lut->comp_expr[i] = NULL;
142 av_freep(&lut->comp_expr_str[i]);
146 #define YUV_FORMATS \
147 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV420P, \
148 AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV440P, \
149 AV_PIX_FMT_YUVA420P, \
150 AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P, \
153 #define RGB_FORMATS \
154 AV_PIX_FMT_ARGB, AV_PIX_FMT_RGBA, \
155 AV_PIX_FMT_ABGR, AV_PIX_FMT_BGRA, \
156 AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24
158 static enum AVPixelFormat yuv_pix_fmts[] = { YUV_FORMATS, AV_PIX_FMT_NONE };
159 static enum AVPixelFormat rgb_pix_fmts[] = { RGB_FORMATS, AV_PIX_FMT_NONE };
160 static enum AVPixelFormat all_pix_fmts[] = { RGB_FORMATS, YUV_FORMATS, AV_PIX_FMT_NONE };
162 static int query_formats(AVFilterContext *ctx)
164 LutContext *lut = ctx->priv;
166 enum AVPixelFormat *pix_fmts = lut->is_rgb ? rgb_pix_fmts :
167 lut->is_yuv ? yuv_pix_fmts : all_pix_fmts;
169 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
174 * Clip value val in the minval - maxval range.
176 static double clip(void *opaque, double val)
178 LutContext *lut = opaque;
179 double minval = lut->var_values[VAR_MINVAL];
180 double maxval = lut->var_values[VAR_MAXVAL];
182 return av_clip(val, minval, maxval);
186 * Compute gamma correction for value val, assuming the minval-maxval
187 * range, val is clipped to a value contained in the same interval.
189 static double compute_gammaval(void *opaque, double gamma)
191 LutContext *lut = opaque;
192 double val = lut->var_values[VAR_CLIPVAL];
193 double minval = lut->var_values[VAR_MINVAL];
194 double maxval = lut->var_values[VAR_MAXVAL];
196 return pow((val-minval)/(maxval-minval), gamma) * (maxval-minval)+minval;
199 static double (* const funcs1[])(void *, double) = {
205 static const char * const funcs1_names[] = {
211 static int config_props(AVFilterLink *inlink)
213 AVFilterContext *ctx = inlink->dst;
214 LutContext *lut = ctx->priv;
215 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
219 lut->hsub = desc->log2_chroma_w;
220 lut->vsub = desc->log2_chroma_h;
222 lut->var_values[VAR_W] = inlink->w;
223 lut->var_values[VAR_H] = inlink->h;
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 min[Y] = min[U] = min[V] = 16;
235 max[U] = max[V] = 240;
236 min[A] = 0; max[A] = 255;
239 min[0] = min[1] = min[2] = min[3] = 0;
240 max[0] = max[1] = max[2] = max[3] = 255;
243 lut->is_yuv = lut->is_rgb = 0;
244 if (ff_fmt_is_in(inlink->format, yuv_pix_fmts)) lut->is_yuv = 1;
245 else if (ff_fmt_is_in(inlink->format, rgb_pix_fmts)) lut->is_rgb = 1;
248 switch (inlink->format) {
249 case AV_PIX_FMT_ARGB: lut->rgba_map[A] = 0; lut->rgba_map[R] = 1; lut->rgba_map[G] = 2; lut->rgba_map[B] = 3; break;
250 case AV_PIX_FMT_ABGR: lut->rgba_map[A] = 0; lut->rgba_map[B] = 1; lut->rgba_map[G] = 2; lut->rgba_map[R] = 3; break;
251 case AV_PIX_FMT_RGBA:
252 case AV_PIX_FMT_RGB24: lut->rgba_map[R] = 0; lut->rgba_map[G] = 1; lut->rgba_map[B] = 2; lut->rgba_map[A] = 3; break;
253 case AV_PIX_FMT_BGRA:
254 case AV_PIX_FMT_BGR24: lut->rgba_map[B] = 0; lut->rgba_map[G] = 1; lut->rgba_map[R] = 2; lut->rgba_map[A] = 3; break;
256 lut->step = av_get_bits_per_pixel(desc) >> 3;
259 for (comp = 0; comp < desc->nb_components; comp++) {
262 /* create the parsed expression */
263 ret = av_expr_parse(&lut->comp_expr[comp], lut->comp_expr_str[comp],
264 var_names, funcs1_names, funcs1, NULL, NULL, 0, ctx);
266 av_log(ctx, AV_LOG_ERROR,
267 "Error when parsing the expression '%s' for the component %d.\n",
268 lut->comp_expr_str[comp], comp);
269 return AVERROR(EINVAL);
272 /* compute the lut */
273 lut->var_values[VAR_MAXVAL] = max[comp];
274 lut->var_values[VAR_MINVAL] = min[comp];
276 for (val = 0; val < 256; val++) {
277 lut->var_values[VAR_VAL] = val;
278 lut->var_values[VAR_CLIPVAL] = av_clip(val, min[comp], max[comp]);
279 lut->var_values[VAR_NEGVAL] =
280 av_clip(min[comp] + max[comp] - lut->var_values[VAR_VAL],
281 min[comp], max[comp]);
283 res = av_expr_eval(lut->comp_expr[comp], lut->var_values, lut);
285 av_log(ctx, AV_LOG_ERROR,
286 "Error when evaluating the expression '%s' for the value %d for the component #%d.\n",
287 lut->comp_expr_str[comp], val, comp);
288 return AVERROR(EINVAL);
290 lut->lut[comp][val] = av_clip((int)res, min[comp], max[comp]);
291 av_log(ctx, AV_LOG_DEBUG, "val[%d][%d] = %d\n", comp, val, lut->lut[comp][val]);
298 static int draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
300 AVFilterContext *ctx = inlink->dst;
301 LutContext *lut = ctx->priv;
302 AVFilterLink *outlink = ctx->outputs[0];
303 AVFilterBufferRef *inpic = inlink ->cur_buf;
304 AVFilterBufferRef *outpic = outlink->out_buf;
305 uint8_t *inrow, *outrow, *inrow0, *outrow0;
310 inrow0 = inpic ->data[0] + y * inpic ->linesize[0];
311 outrow0 = outpic->data[0] + y * outpic->linesize[0];
313 for (i = 0; i < h; i ++) {
316 for (j = 0; j < inlink->w; j++) {
317 for (k = 0; k < lut->step; k++)
318 outrow[k] = lut->lut[lut->rgba_map[k]][inrow[k]];
322 inrow0 += inpic ->linesize[0];
323 outrow0 += outpic->linesize[0];
327 for (plane = 0; plane < 4 && inpic->data[plane]; plane++) {
328 int vsub = plane == 1 || plane == 2 ? lut->vsub : 0;
329 int hsub = plane == 1 || plane == 2 ? lut->hsub : 0;
331 inrow = inpic ->data[plane] + (y>>vsub) * inpic ->linesize[plane];
332 outrow = outpic->data[plane] + (y>>vsub) * outpic->linesize[plane];
334 for (i = 0; i < h>>vsub; i ++) {
335 for (j = 0; j < inlink->w>>hsub; j++)
336 outrow[j] = lut->lut[plane][inrow[j]];
337 inrow += inpic ->linesize[plane];
338 outrow += outpic->linesize[plane];
343 return ff_draw_slice(outlink, y, h, slice_dir);
346 static const AVFilterPad inputs[] = {
348 .type = AVMEDIA_TYPE_VIDEO,
349 .draw_slice = draw_slice,
350 .config_props = config_props,
351 .min_perms = AV_PERM_READ, },
354 static const AVFilterPad outputs[] = {
356 .type = AVMEDIA_TYPE_VIDEO, },
359 #define DEFINE_LUT_FILTER(name_, description_, init_) \
360 AVFilter avfilter_vf_##name_ = { \
362 .description = NULL_IF_CONFIG_SMALL(description_), \
363 .priv_size = sizeof(LutContext), \
367 .query_formats = query_formats, \
370 .outputs = outputs, \
373 #if CONFIG_LUT_FILTER
374 DEFINE_LUT_FILTER(lut, "Compute and apply a lookup table to the RGB/YUV input video.", init);
376 #if CONFIG_LUTYUV_FILTER
377 DEFINE_LUT_FILTER(lutyuv, "Compute and apply a lookup table to the YUV input video.", init);
379 #if CONFIG_LUTRGB_FILTER
380 DEFINE_LUT_FILTER(lutrgb, "Compute and apply a lookup table to the RGB input video.", init);
383 #if CONFIG_NEGATE_FILTER
385 static int negate_init(AVFilterContext *ctx, const char *args)
387 LutContext *lut = ctx->priv;
391 sscanf(args, "%d", &lut->negate_alpha);
393 av_log(ctx, AV_LOG_DEBUG, "negate_alpha:%d\n", lut->negate_alpha);
395 snprintf(lut_params, sizeof(lut_params), "c0=negval:c1=negval:c2=negval:a=%s",
396 lut->negate_alpha ? "negval" : "val");
398 return init(ctx, lut_params);
401 DEFINE_LUT_FILTER(negate, "Negate input video.", negate_init);