2 * Copyright (c) 2011 Stefano Sabatini
4 * This file is part of FFmpeg.
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.
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.
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
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/opt.h"
29 #include "libavutil/pixdesc.h"
35 static const char *const var_names[] = {
36 "w", ///< width of the input video
37 "h", ///< height of the input video
38 "val", ///< input value for the pixel
39 "maxval", ///< max value for the pixel
40 "minval", ///< min value for the pixel
41 "negval", ///< negated value
59 uint8_t lut[4][256]; ///< lookup table for each component
60 char *comp_expr_str[4];
63 double var_values[VAR_VARS_NB];
66 int negate_alpha; /* only used by negate */
77 #define OFFSET(x) offsetof(LutContext, x)
79 static const AVOption lut_options[] = {
80 {"c0", "set component #0 expression", OFFSET(comp_expr_str[0]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
81 {"c1", "set component #1 expression", OFFSET(comp_expr_str[1]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
82 {"c2", "set component #2 expression", OFFSET(comp_expr_str[2]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
83 {"c3", "set component #3 expression", OFFSET(comp_expr_str[3]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
84 {"y", "set Y expression", OFFSET(comp_expr_str[Y]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
85 {"u", "set U expression", OFFSET(comp_expr_str[U]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
86 {"v", "set V expression", OFFSET(comp_expr_str[V]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
87 {"r", "set R expression", OFFSET(comp_expr_str[R]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
88 {"g", "set G expression", OFFSET(comp_expr_str[G]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
89 {"b", "set B expression", OFFSET(comp_expr_str[B]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
90 {"a", "set A expression", OFFSET(comp_expr_str[A]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
94 AVFILTER_DEFINE_CLASS(lut);
96 static int init(AVFilterContext *ctx, const char *args)
98 LutContext *lut = ctx->priv;
101 lut->class = &lut_class;
102 av_opt_set_defaults(lut);
104 lut->is_rgb = !strcmp(ctx->filter->name, "lutrgb");
105 lut->is_yuv = !strcmp(ctx->filter->name, "lutyuv");
106 if (args && (ret = av_set_options_string(lut, args, "=", ":")) < 0)
112 static av_cold void uninit(AVFilterContext *ctx)
114 LutContext *lut = ctx->priv;
117 for (i = 0; i < 4; i++) {
118 av_expr_free(lut->comp_expr[i]);
119 lut->comp_expr[i] = NULL;
120 av_freep(&lut->comp_expr_str[i]);
124 #define YUV_FORMATS \
125 PIX_FMT_YUV444P, PIX_FMT_YUV422P, PIX_FMT_YUV420P, \
126 PIX_FMT_YUV411P, PIX_FMT_YUV410P, PIX_FMT_YUV440P, \
128 PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P, \
131 #define RGB_FORMATS \
132 PIX_FMT_ARGB, PIX_FMT_RGBA, \
133 PIX_FMT_ABGR, PIX_FMT_BGRA, \
134 PIX_FMT_RGB24, PIX_FMT_BGR24
136 static const enum PixelFormat yuv_pix_fmts[] = { YUV_FORMATS, PIX_FMT_NONE };
137 static const enum PixelFormat rgb_pix_fmts[] = { RGB_FORMATS, PIX_FMT_NONE };
138 static const enum PixelFormat all_pix_fmts[] = { RGB_FORMATS, YUV_FORMATS, PIX_FMT_NONE };
140 static int query_formats(AVFilterContext *ctx)
142 LutContext *lut = ctx->priv;
144 const enum PixelFormat *pix_fmts = lut->is_rgb ? rgb_pix_fmts :
145 lut->is_yuv ? yuv_pix_fmts : all_pix_fmts;
147 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
152 * Clip value val in the minval - maxval range.
154 static double clip(void *opaque, double val)
156 LutContext *lut = opaque;
157 double minval = lut->var_values[VAR_MINVAL];
158 double maxval = lut->var_values[VAR_MAXVAL];
160 return av_clip(val, minval, maxval);
164 * Compute gamma correction for value val, assuming the minval-maxval
165 * range, val is clipped to a value contained in the same interval.
167 static double compute_gammaval(void *opaque, double gamma)
169 LutContext *lut = opaque;
170 double val = lut->var_values[VAR_CLIPVAL];
171 double minval = lut->var_values[VAR_MINVAL];
172 double maxval = lut->var_values[VAR_MAXVAL];
174 return pow((val-minval)/(maxval-minval), gamma) * (maxval-minval)+minval;
177 static double (* const funcs1[])(void *, double) = {
179 (void *)compute_gammaval,
183 static const char * const funcs1_names[] = {
189 static int config_props(AVFilterLink *inlink)
191 AVFilterContext *ctx = inlink->dst;
192 LutContext *lut = ctx->priv;
193 const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[inlink->format];
194 int rgba_map[4]; /* component index -> RGBA color index map */
198 lut->hsub = desc->log2_chroma_w;
199 lut->vsub = desc->log2_chroma_h;
201 lut->var_values[VAR_W] = inlink->w;
202 lut->var_values[VAR_H] = inlink->h;
204 switch (inlink->format) {
205 case PIX_FMT_YUV410P:
206 case PIX_FMT_YUV411P:
207 case PIX_FMT_YUV420P:
208 case PIX_FMT_YUV422P:
209 case PIX_FMT_YUV440P:
210 case PIX_FMT_YUV444P:
211 case PIX_FMT_YUVA420P:
212 min[Y] = min[U] = min[V] = 16;
214 max[U] = max[V] = 240;
215 min[A] = 0; max[A] = 255;
218 min[0] = min[1] = min[2] = min[3] = 0;
219 max[0] = max[1] = max[2] = max[3] = 255;
222 lut->is_yuv = lut->is_rgb = 0;
223 if (ff_fmt_is_in(inlink->format, yuv_pix_fmts)) lut->is_yuv = 1;
224 else if (ff_fmt_is_in(inlink->format, rgb_pix_fmts)) lut->is_rgb = 1;
227 switch (inlink->format) {
228 case PIX_FMT_ARGB: rgba_map[0] = A; rgba_map[1] = R; rgba_map[2] = G; rgba_map[3] = B; break;
229 case PIX_FMT_ABGR: rgba_map[0] = A; rgba_map[1] = B; rgba_map[2] = G; rgba_map[3] = R; break;
231 case PIX_FMT_RGB24: rgba_map[0] = R; rgba_map[1] = G; rgba_map[2] = B; rgba_map[3] = A; break;
233 case PIX_FMT_BGR24: rgba_map[0] = B; rgba_map[1] = G; rgba_map[2] = R; rgba_map[3] = A; break;
235 lut->step = av_get_bits_per_pixel(desc) >> 3;
238 for (comp = 0; comp < desc->nb_components; comp++) {
240 int color = lut->is_rgb ? rgba_map[comp] : comp;
242 /* create the parsed expression */
243 ret = av_expr_parse(&lut->comp_expr[color], lut->comp_expr_str[color],
244 var_names, funcs1_names, funcs1, NULL, NULL, 0, ctx);
246 av_log(ctx, AV_LOG_ERROR,
247 "Error when parsing the expression '%s' for the component %d and color %d.\n",
248 lut->comp_expr_str[comp], comp, color);
249 return AVERROR(EINVAL);
252 /* compute the lut */
253 lut->var_values[VAR_MAXVAL] = max[color];
254 lut->var_values[VAR_MINVAL] = min[color];
256 for (val = 0; val < 256; val++) {
257 lut->var_values[VAR_VAL] = val;
258 lut->var_values[VAR_CLIPVAL] = av_clip(val, min[color], max[color]);
259 lut->var_values[VAR_NEGVAL] =
260 av_clip(min[color] + max[color] - lut->var_values[VAR_VAL],
261 min[color], max[color]);
263 res = av_expr_eval(lut->comp_expr[color], lut->var_values, lut);
265 av_log(ctx, AV_LOG_ERROR,
266 "Error when evaluating the expression '%s' for the value %d for the component %d.\n",
267 lut->comp_expr_str[color], val, comp);
268 return AVERROR(EINVAL);
270 lut->lut[comp][val] = av_clip((int)res, min[color], max[color]);
271 av_log(ctx, AV_LOG_DEBUG, "val[%d][%d] = %d\n", comp, val, lut->lut[comp][val]);
278 static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
280 AVFilterContext *ctx = inlink->dst;
281 LutContext *lut = ctx->priv;
282 AVFilterLink *outlink = ctx->outputs[0];
283 AVFilterBufferRef *inpic = inlink ->cur_buf;
284 AVFilterBufferRef *outpic = outlink->out_buf;
285 uint8_t *inrow, *outrow, *inrow0, *outrow0;
290 inrow0 = inpic ->data[0] + y * inpic ->linesize[0];
291 outrow0 = outpic->data[0] + y * outpic->linesize[0];
293 for (i = 0; i < h; i ++) {
295 const uint8_t (*tab)[256] = (const uint8_t (*)[256])lut->lut;
298 for (j = 0; j < w; j++) {
299 outrow[0] = tab[0][inrow[0]];
301 outrow[1] = tab[1][inrow[1]];
303 outrow[2] = tab[2][inrow[2]];
305 outrow[3] = tab[3][inrow[3]];
312 inrow0 += inpic ->linesize[0];
313 outrow0 += outpic->linesize[0];
317 for (plane = 0; plane < 4 && inpic->data[plane]; plane++) {
318 int vsub = plane == 1 || plane == 2 ? lut->vsub : 0;
319 int hsub = plane == 1 || plane == 2 ? lut->hsub : 0;
321 inrow = inpic ->data[plane] + (y>>vsub) * inpic ->linesize[plane];
322 outrow = outpic->data[plane] + (y>>vsub) * outpic->linesize[plane];
324 for (i = 0; i < (h + (1<<vsub) - 1)>>vsub; i ++) {
325 const uint8_t *tab = lut->lut[plane];
326 int w = (inlink->w + (1<<hsub) - 1)>>hsub;
327 for (j = 0; j < w; j++)
328 outrow[j] = tab[inrow[j]];
329 inrow += inpic ->linesize[plane];
330 outrow += outpic->linesize[plane];
335 ff_draw_slice(outlink, y, h, slice_dir);
338 #define DEFINE_LUT_FILTER(name_, description_, init_) \
339 AVFilter avfilter_vf_##name_ = { \
341 .description = NULL_IF_CONFIG_SMALL(description_), \
342 .priv_size = sizeof(LutContext), \
346 .query_formats = query_formats, \
348 .inputs = (const AVFilterPad[]) {{ .name = "default", \
349 .type = AVMEDIA_TYPE_VIDEO, \
350 .draw_slice = draw_slice, \
351 .config_props = config_props, \
352 .min_perms = AV_PERM_READ, }, \
354 .outputs = (const AVFilterPad[]) {{ .name = "default", \
355 .type = AVMEDIA_TYPE_VIDEO, }, \
359 #if CONFIG_LUT_FILTER
360 DEFINE_LUT_FILTER(lut, "Compute and apply a lookup table to the RGB/YUV input video.", init);
362 #if CONFIG_LUTYUV_FILTER
363 DEFINE_LUT_FILTER(lutyuv, "Compute and apply a lookup table to the YUV input video.", init);
365 #if CONFIG_LUTRGB_FILTER
366 DEFINE_LUT_FILTER(lutrgb, "Compute and apply a lookup table to the RGB input video.", init);
369 #if CONFIG_NEGATE_FILTER
371 static int negate_init(AVFilterContext *ctx, const char *args)
373 LutContext *lut = ctx->priv;
377 sscanf(args, "%d", &lut->negate_alpha);
379 av_log(ctx, AV_LOG_DEBUG, "negate_alpha:%d\n", lut->negate_alpha);
381 snprintf(lut_params, sizeof(lut_params), "c0=negval:c1=negval:c2=negval:a=%s",
382 lut->negate_alpha ? "negval" : "val");
384 return init(ctx, lut_params);
387 DEFINE_LUT_FILTER(negate, "Negate input video.", negate_init);