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"
33 static const char * const var_names[] = {
34 "w", ///< width of the input video
35 "h", ///< height of the input video
36 "val", ///< input value for the pixel
37 "maxval", ///< max value for the pixel
38 "minval", ///< min value for the pixel
39 "negval", ///< negated value
57 uint8_t lut[4][256]; ///< lookup table for each component
58 char *comp_expr_str[4];
61 double var_values[VAR_VARS_NB];
65 int negate_alpha; /* only used by negate */
76 #define OFFSET(x) offsetof(LutContext, x)
78 static const AVOption lut_options[] = {
79 {"c0", "set component #0 expression", OFFSET(comp_expr_str[0]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
80 {"c1", "set component #1 expression", OFFSET(comp_expr_str[1]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
81 {"c2", "set component #2 expression", OFFSET(comp_expr_str[2]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
82 {"c3", "set component #3 expression", OFFSET(comp_expr_str[3]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
83 {"y", "set Y expression", OFFSET(comp_expr_str[Y]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
84 {"u", "set U expression", OFFSET(comp_expr_str[U]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
85 {"v", "set V expression", OFFSET(comp_expr_str[V]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
86 {"r", "set R expression", OFFSET(comp_expr_str[R]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
87 {"g", "set G expression", OFFSET(comp_expr_str[G]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
88 {"b", "set B expression", OFFSET(comp_expr_str[B]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
89 {"a", "set A expression", OFFSET(comp_expr_str[A]), AV_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
93 static const char *lut_get_name(void *ctx)
98 static const AVClass lut_class = {
104 static int init(AVFilterContext *ctx, const char *args, void *opaque)
106 LutContext *lut = ctx->priv;
109 lut->class = &lut_class;
110 av_opt_set_defaults(lut);
112 lut->is_rgb = !strcmp(ctx->filter->name, "lutrgb");
113 lut->is_yuv = !strcmp(ctx->filter->name, "lutyuv");
114 if (args && (ret = av_set_options_string(lut, args, "=", ":")) < 0)
120 static av_cold void uninit(AVFilterContext *ctx)
122 LutContext *lut = ctx->priv;
125 for (i = 0; i < 4; i++) {
126 av_expr_free(lut->comp_expr[i]);
127 lut->comp_expr[i] = NULL;
128 av_freep(&lut->comp_expr_str[i]);
132 #define YUV_FORMATS \
133 PIX_FMT_YUV444P, PIX_FMT_YUV422P, PIX_FMT_YUV420P, \
134 PIX_FMT_YUV411P, PIX_FMT_YUV410P, PIX_FMT_YUV440P, \
136 PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P, \
139 #define RGB_FORMATS \
140 PIX_FMT_ARGB, PIX_FMT_RGBA, \
141 PIX_FMT_ABGR, PIX_FMT_BGRA, \
142 PIX_FMT_RGB24, PIX_FMT_BGR24
144 static const enum PixelFormat yuv_pix_fmts[] = { YUV_FORMATS, PIX_FMT_NONE };
145 static const enum PixelFormat rgb_pix_fmts[] = { RGB_FORMATS, PIX_FMT_NONE };
146 static const enum PixelFormat all_pix_fmts[] = { RGB_FORMATS, YUV_FORMATS, PIX_FMT_NONE };
148 static int query_formats(AVFilterContext *ctx)
150 LutContext *lut = ctx->priv;
152 const enum PixelFormat *pix_fmts = lut->is_rgb ? rgb_pix_fmts :
153 lut->is_yuv ? yuv_pix_fmts : all_pix_fmts;
155 avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
160 * Clip value val in the minval - maxval range.
162 static double clip(void *opaque, double val)
164 LutContext *lut = opaque;
165 double minval = lut->var_values[VAR_MINVAL];
166 double maxval = lut->var_values[VAR_MAXVAL];
168 return av_clip(val, minval, maxval);
172 * Compute gamma correction for value val, assuming the minval-maxval
173 * range, val is clipped to a value contained in the same interval.
175 static double compute_gammaval(void *opaque, double gamma)
177 LutContext *lut = opaque;
178 double val = lut->var_values[VAR_CLIPVAL];
179 double minval = lut->var_values[VAR_MINVAL];
180 double maxval = lut->var_values[VAR_MAXVAL];
182 return pow((val-minval)/(maxval-minval), gamma) * (maxval-minval)+minval;
185 static double (* const funcs1[])(void *, double) = {
187 (void *)compute_gammaval,
191 static const char * const funcs1_names[] = {
197 static int config_props(AVFilterLink *inlink)
199 AVFilterContext *ctx = inlink->dst;
200 LutContext *lut = ctx->priv;
201 const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[inlink->format];
205 lut->hsub = desc->log2_chroma_w;
206 lut->vsub = desc->log2_chroma_h;
208 lut->var_values[VAR_W] = inlink->w;
209 lut->var_values[VAR_H] = inlink->h;
211 switch (inlink->format) {
212 case PIX_FMT_YUV410P:
213 case PIX_FMT_YUV411P:
214 case PIX_FMT_YUV420P:
215 case PIX_FMT_YUV422P:
216 case PIX_FMT_YUV440P:
217 case PIX_FMT_YUV444P:
218 case PIX_FMT_YUVA420P:
219 min[Y] = min[U] = min[V] = 16;
221 max[U] = max[V] = 240;
222 min[A] = 0; max[A] = 255;
225 min[0] = min[1] = min[2] = min[3] = 0;
226 max[0] = max[1] = max[2] = max[3] = 255;
229 lut->is_yuv = lut->is_rgb = 0;
230 if (ff_fmt_is_in(inlink->format, yuv_pix_fmts)) lut->is_yuv = 1;
231 else if (ff_fmt_is_in(inlink->format, rgb_pix_fmts)) lut->is_rgb = 1;
234 switch (inlink->format) {
235 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;
236 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;
238 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;
240 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;
242 lut->step = av_get_bits_per_pixel(desc) >> 3;
245 for (comp = 0; comp < desc->nb_components; comp++) {
248 /* create the parsed expression */
249 ret = av_expr_parse(&lut->comp_expr[comp], lut->comp_expr_str[comp],
250 var_names, funcs1_names, funcs1, NULL, NULL, 0, ctx);
252 av_log(ctx, AV_LOG_ERROR,
253 "Error when parsing the expression '%s' for the component %d.\n",
254 lut->comp_expr_str[comp], comp);
255 return AVERROR(EINVAL);
258 /* compute the lut */
259 lut->var_values[VAR_MAXVAL] = max[comp];
260 lut->var_values[VAR_MINVAL] = min[comp];
262 for (val = 0; val < 256; val++) {
263 lut->var_values[VAR_VAL] = val;
264 lut->var_values[VAR_CLIPVAL] = av_clip(val, min[comp], max[comp]);
265 lut->var_values[VAR_NEGVAL] =
266 av_clip(min[comp] + max[comp] - lut->var_values[VAR_VAL],
267 min[comp], max[comp]);
269 res = av_expr_eval(lut->comp_expr[comp], lut->var_values, lut);
271 av_log(ctx, AV_LOG_ERROR,
272 "Error when evaluating the expression '%s' for the value %d for the component #%d.\n",
273 lut->comp_expr_str[comp], val, comp);
274 return AVERROR(EINVAL);
276 lut->lut[comp][val] = av_clip((int)res, min[comp], max[comp]);
277 av_log(ctx, AV_LOG_DEBUG, "val[%d][%d] = %d\n", comp, val, lut->lut[comp][val]);
284 static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
286 AVFilterContext *ctx = inlink->dst;
287 LutContext *lut = ctx->priv;
288 AVFilterLink *outlink = ctx->outputs[0];
289 AVFilterBufferRef *inpic = inlink ->cur_buf;
290 AVFilterBufferRef *outpic = outlink->out_buf;
291 uint8_t *inrow, *outrow, *inrow0, *outrow0;
296 inrow0 = inpic ->data[0] + y * inpic ->linesize[0];
297 outrow0 = outpic->data[0] + y * outpic->linesize[0];
299 for (i = 0; i < h; i ++) {
302 for (j = 0; j < inlink->w; j++) {
303 for (k = 0; k < lut->step; k++)
304 outrow[k] = lut->lut[lut->rgba_map[k]][inrow[k]];
308 inrow0 += inpic ->linesize[0];
309 outrow0 += outpic->linesize[0];
313 for (plane = 0; plane < 4 && inpic->data[plane]; plane++) {
314 int vsub = plane == 1 || plane == 2 ? lut->vsub : 0;
315 int hsub = plane == 1 || plane == 2 ? lut->hsub : 0;
317 inrow = inpic ->data[plane] + (y>>vsub) * inpic ->linesize[plane];
318 outrow = outpic->data[plane] + (y>>vsub) * outpic->linesize[plane];
320 for (i = 0; i < h>>vsub; i ++) {
321 for (j = 0; j < inlink->w>>hsub; j++)
322 outrow[j] = lut->lut[plane][inrow[j]];
323 inrow += inpic ->linesize[plane];
324 outrow += outpic->linesize[plane];
329 avfilter_draw_slice(outlink, y, h, slice_dir);
332 #define DEFINE_LUT_FILTER(name_, description_, init_) \
333 AVFilter avfilter_vf_##name_ = { \
335 .description = NULL_IF_CONFIG_SMALL(description_), \
336 .priv_size = sizeof(LutContext), \
340 .query_formats = query_formats, \
342 .inputs = (const AVFilterPad[]) {{ .name = "default", \
343 .type = AVMEDIA_TYPE_VIDEO, \
344 .draw_slice = draw_slice, \
345 .config_props = config_props, \
346 .min_perms = AV_PERM_READ, }, \
348 .outputs = (const AVFilterPad[]) {{ .name = "default", \
349 .type = AVMEDIA_TYPE_VIDEO, }, \
353 #if CONFIG_LUT_FILTER
354 DEFINE_LUT_FILTER(lut, "Compute and apply a lookup table to the RGB/YUV input video.", init);
356 #if CONFIG_LUTYUV_FILTER
357 DEFINE_LUT_FILTER(lutyuv, "Compute and apply a lookup table to the YUV input video.", init);
359 #if CONFIG_LUTRGB_FILTER
360 DEFINE_LUT_FILTER(lutrgb, "Compute and apply a lookup table to the RGB input video.", init);
363 #if CONFIG_NEGATE_FILTER
365 static int negate_init(AVFilterContext *ctx, const char *args, void *opaque)
367 LutContext *lut = ctx->priv;
371 sscanf(args, "%d", &lut->negate_alpha);
373 av_log(ctx, AV_LOG_DEBUG, "negate_alpha:%d\n", lut->negate_alpha);
375 snprintf(lut_params, sizeof(lut_params), "c0=negval:c1=negval:c2=negval:a=%s",
376 lut->negate_alpha ? "negval" : "val");
378 return init(ctx, lut_params, opaque);
381 DEFINE_LUT_FILTER(negate, "Negate input video.", negate_init);