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/eval.h"
28 #include "libavutil/mathematics.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/pixdesc.h"
34 static const char *const var_names[] = {
38 "w", ///< width of the input video
39 "h", ///< height of the input video
40 "val", ///< input value for the pixel
41 "maxval", ///< max value for the pixel
42 "minval", ///< min value for the pixel
43 "negval", ///< negated value
64 uint8_t lut[4][256]; ///< lookup table for each component
65 char *comp_expr_str[4];
68 double var_values[VAR_VARS_NB];
72 int negate_alpha; /* only used by negate */
83 #define OFFSET(x) offsetof(LutContext, x)
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},
100 static const char *lut_get_name(void *ctx)
105 static const AVClass lut_class = {
111 static int init(AVFilterContext *ctx, const char *args, void *opaque)
113 LutContext *lut = ctx->priv;
116 lut->class = &lut_class;
117 av_opt_set_defaults(lut);
119 lut->var_values[VAR_PHI] = M_PHI;
120 lut->var_values[VAR_PI] = M_PI;
121 lut->var_values[VAR_E ] = M_E;
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)
131 static av_cold void uninit(AVFilterContext *ctx)
133 LutContext *lut = ctx->priv;
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]);
143 #define YUV_FORMATS \
144 PIX_FMT_YUV444P, PIX_FMT_YUV422P, PIX_FMT_YUV420P, \
145 PIX_FMT_YUV411P, PIX_FMT_YUV410P, PIX_FMT_YUV440P, \
147 PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P, \
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
155 static enum PixelFormat yuv_pix_fmts[] = { YUV_FORMATS, PIX_FMT_NONE };
156 static enum PixelFormat rgb_pix_fmts[] = { RGB_FORMATS, PIX_FMT_NONE };
157 static enum PixelFormat all_pix_fmts[] = { RGB_FORMATS, YUV_FORMATS, PIX_FMT_NONE };
159 static int query_formats(AVFilterContext *ctx)
161 LutContext *lut = ctx->priv;
163 enum PixelFormat *pix_fmts = lut->is_rgb ? rgb_pix_fmts :
164 lut->is_yuv ? yuv_pix_fmts : all_pix_fmts;
166 avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
171 * Clip value val in the minval - maxval range.
173 static double clip(void *opaque, double val)
175 LutContext *lut = opaque;
176 double minval = lut->var_values[VAR_MINVAL];
177 double maxval = lut->var_values[VAR_MAXVAL];
179 return av_clip(val, minval, maxval);
183 * Compute gamma correction for value val, assuming the minval-maxval
184 * range, val is clipped to a value contained in the same interval.
186 static double compute_gammaval(void *opaque, double gamma)
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];
193 return pow((val-minval)/(maxval-minval), gamma) * (maxval-minval)+minval;
196 static double (* const funcs1[])(void *, double) = {
202 static const char * const funcs1_names[] = {
208 static int config_props(AVFilterLink *inlink)
210 AVFilterContext *ctx = inlink->dst;
211 LutContext *lut = ctx->priv;
212 const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[inlink->format];
216 lut->hsub = desc->log2_chroma_w;
217 lut->vsub = desc->log2_chroma_h;
219 lut->var_values[VAR_W] = inlink->w;
220 lut->var_values[VAR_H] = inlink->h;
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;
232 max[U] = max[V] = 240;
233 min[A] = 0; max[A] = 255;
236 min[0] = min[1] = min[2] = min[3] = 0;
237 max[0] = max[1] = max[2] = max[3] = 255;
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;
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;
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;
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;
253 lut->step = av_get_bits_per_pixel(desc) >> 3;
256 for (comp = 0; comp < desc->nb_components; comp++) {
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);
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);
269 /* compute the lut */
270 lut->var_values[VAR_MAXVAL] = max[comp];
271 lut->var_values[VAR_MINVAL] = min[comp];
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]);
280 res = av_expr_eval(lut->comp_expr[comp], lut->var_values, lut);
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);
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]);
295 static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
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;
307 inrow0 = inpic ->data[0] + y * inpic ->linesize[0];
308 outrow0 = outpic->data[0] + y * outpic->linesize[0];
310 for (i = 0; i < h; i ++) {
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]];
319 inrow0 += inpic ->linesize[0];
320 outrow0 += outpic->linesize[0];
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;
328 inrow = inpic ->data[plane] + (y>>vsub) * inpic ->linesize[plane];
329 outrow = outpic->data[plane] + (y>>vsub) * outpic->linesize[plane];
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];
340 avfilter_draw_slice(outlink, y, h, slice_dir);
343 #define DEFINE_LUT_FILTER(name_, description_, init_) \
344 AVFilter avfilter_vf_##name_ = { \
346 .description = NULL_IF_CONFIG_SMALL(description_), \
347 .priv_size = sizeof(LutContext), \
351 .query_formats = query_formats, \
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, }, \
359 .outputs = (AVFilterPad[]) {{ .name = "default", \
360 .type = AVMEDIA_TYPE_VIDEO, }, \
364 #if CONFIG_LUT_FILTER
365 DEFINE_LUT_FILTER(lut, "Compute and apply a lookup table to the RGB/YUV input video.", init);
367 #if CONFIG_LUTYUV_FILTER
368 DEFINE_LUT_FILTER(lutyuv, "Compute and apply a lookup table to the YUV input video.", init);
370 #if CONFIG_LUTRGB_FILTER
371 DEFINE_LUT_FILTER(lutrgb, "Compute and apply a lookup table to the RGB input video.", init);
374 #if CONFIG_NEGATE_FILTER
376 static int negate_init(AVFilterContext *ctx, const char *args, void *opaque)
378 LutContext *lut = ctx->priv;
382 sscanf(args, "%d", &lut->negate_alpha);
384 av_log(ctx, AV_LOG_DEBUG, "negate_alpha:%d\n", lut->negate_alpha);
386 snprintf(lut_params, sizeof(lut_params), "c0=negval:c1=negval:c2=negval:a=%s",
387 lut->negate_alpha ? "negval" : "val");
389 return init(ctx, lut_params, opaque);
392 DEFINE_LUT_FILTER(negate, "Negate input video.", negate_init);