libavfilter/vf_lut.c

   1 /*
   2  * Copyright (c) 2011 Stefano Sabatini
   3  *
   4  * This file is part of Libav.
   5  *
   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.
  10  *
  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.
  15  *
  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
  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/common.h"
  28 #include "libavutil/eval.h"
  29 #include "libavutil/mathematics.h"
  30 #include "libavutil/opt.h"
  31 #include "libavutil/pixdesc.h"
  32 #include "avfilter.h"
  33 #include "formats.h"
  34 #include "internal.h"
  35 #include "video.h"
  36
  37 static const char *const var_names[] = {
  38     "E",
  39     "PHI",
  40     "PI",
  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
  47     "clipval",
  48     NULL
  49 };
  50
  51 enum var_name {
  52     VAR_E,
  53     VAR_PHI,
  54     VAR_PI,
  55     VAR_W,
  56     VAR_H,
  57     VAR_VAL,
  58     VAR_MAXVAL,
  59     VAR_MINVAL,
  60     VAR_NEGVAL,
  61     VAR_CLIPVAL,
  62     VAR_VARS_NB
  63 };
  64
  65 typedef struct {
  66     const AVClass *class;
  67     uint8_t lut[4][256];  ///< lookup table for each component
  68     char   *comp_expr_str[4];
  69     AVExpr *comp_expr[4];
  70     int hsub, vsub;
  71     double var_values[VAR_VARS_NB];
  72     int is_rgb, is_yuv;
  73     int rgba_map[4];
  74     int step;
  75     int negate_alpha; /* only used by negate */
  76 } LutContext;
  77
  78 #define Y 0
  79 #define U 1
  80 #define V 2
  81 #define R 0
  82 #define G 1
  83 #define B 2
  84 #define A 3
  85
  86 #define OFFSET(x) offsetof(LutContext, x)
  87
  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},
 100     {NULL},
 101 };
 102
 103 static const char *lut_get_name(void *ctx)
 104 {
 105     return "lut";
 106 }
 107
 108 static const AVClass lut_class = {
 109     "LutContext",
 110     lut_get_name,
 111     lut_options
 112 };
 113
 114 static int init(AVFilterContext *ctx, const char *args)
 115 {
 116     LutContext *lut = ctx->priv;
 117     int ret;
 118
 119     lut->class = &lut_class;
 120     av_opt_set_defaults(lut);
 121
 122     lut->var_values[VAR_PHI] = M_PHI;
 123     lut->var_values[VAR_PI]  = M_PI;
 124     lut->var_values[VAR_E ]  = M_E;
 125
 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)
 129         return ret;
 130
 131     return 0;
 132 }
 133
 134 static av_cold void uninit(AVFilterContext *ctx)
 135 {
 136     LutContext *lut = ctx->priv;
 137     int i;
 138
 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]);
 143     }
 144 }
 145
 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,   \
 151     AV_PIX_FMT_YUVJ440P
 152
 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
 157
 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 };
 161
 162 static int query_formats(AVFilterContext *ctx)
 163 {
 164     LutContext *lut = ctx->priv;
 165
 166     enum AVPixelFormat *pix_fmts = lut->is_rgb ? rgb_pix_fmts :
 167                                  lut->is_yuv ? yuv_pix_fmts : all_pix_fmts;
 168
 169     ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
 170     return 0;
 171 }
 172
 173 /**
 174  * Clip value val in the minval - maxval range.
 175  */
 176 static double clip(void *opaque, double val)
 177 {
 178     LutContext *lut = opaque;
 179     double minval = lut->var_values[VAR_MINVAL];
 180     double maxval = lut->var_values[VAR_MAXVAL];
 181
 182     return av_clip(val, minval, maxval);
 183 }
 184
 185 /**
 186  * Compute gamma correction for value val, assuming the minval-maxval
 187  * range, val is clipped to a value contained in the same interval.
 188  */
 189 static double compute_gammaval(void *opaque, double gamma)
 190 {
 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];
 195
 196     return pow((val-minval)/(maxval-minval), gamma) * (maxval-minval)+minval;
 197 }
 198
 199 static double (* const funcs1[])(void *, double) = {
 200     clip,
 201     compute_gammaval,
 202     NULL
 203 };
 204
 205 static const char * const funcs1_names[] = {
 206     "clip",
 207     "gammaval",
 208     NULL
 209 };
 210
 211 static int config_props(AVFilterLink *inlink)
 212 {
 213     AVFilterContext *ctx = inlink->dst;
 214     LutContext *lut = ctx->priv;
 215     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
 216     int min[4], max[4];
 217     int val, comp, ret;
 218
 219     lut->hsub = desc->log2_chroma_w;
 220     lut->vsub = desc->log2_chroma_h;
 221
 222     lut->var_values[VAR_W] = inlink->w;
 223     lut->var_values[VAR_H] = inlink->h;
 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         min[Y] = min[U] = min[V] = 16;
 234         max[Y] = 235;
 235         max[U] = max[V] = 240;
 236         min[A] = 0; max[A] = 255;
 237         break;
 238     default:
 239         min[0] = min[1] = min[2] = min[3] = 0;
 240         max[0] = max[1] = max[2] = max[3] = 255;
 241     }
 242
 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;
 246
 247     if (lut->is_rgb) {
 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;
 255         }
 256         lut->step = av_get_bits_per_pixel(desc) >> 3;
 257     }
 258
 259     for (comp = 0; comp < desc->nb_components; comp++) {
 260         double res;
 261
 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);
 265         if (ret < 0) {
 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);
 270         }
 271
 272         /* compute the lut */
 273         lut->var_values[VAR_MAXVAL] = max[comp];
 274         lut->var_values[VAR_MINVAL] = min[comp];
 275
 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]);
 282
 283             res = av_expr_eval(lut->comp_expr[comp], lut->var_values, lut);
 284             if (isnan(res)) {
 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);
 289             }
 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]);
 292         }
 293     }
 294
 295     return 0;
 296 }
 297
 298 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
 299 {
 300     AVFilterContext *ctx = inlink->dst;
 301     LutContext *lut = ctx->priv;
 302     AVFilterLink *outlink = ctx->outputs[0];
 303     AVFrame *out;
 304     uint8_t *inrow, *outrow, *inrow0, *outrow0;
 305     int i, j, k, plane;
 306
 307     out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
 308     if (!out) {
 309         av_frame_free(&in);
 310         return AVERROR(ENOMEM);
 311     }
 312     av_frame_copy_props(out, in);
 313
 314     if (lut->is_rgb) {
 315         /* packed */
 316         inrow0  = in ->data[0];
 317         outrow0 = out->data[0];
 318
 319         for (i = 0; i < in->height; i ++) {
 320             inrow  = inrow0;
 321             outrow = outrow0;
 322             for (j = 0; j < inlink->w; j++) {
 323                 for (k = 0; k < lut->step; k++)
 324                     outrow[k] = lut->lut[lut->rgba_map[k]][inrow[k]];
 325                 outrow += lut->step;
 326                 inrow  += lut->step;
 327             }
 328             inrow0  += in ->linesize[0];
 329             outrow0 += out->linesize[0];
 330         }
 331     } else {
 332         /* planar */
 333         for (plane = 0; plane < 4 && in->data[plane]; plane++) {
 334             int vsub = plane == 1 || plane == 2 ? lut->vsub : 0;
 335             int hsub = plane == 1 || plane == 2 ? lut->hsub : 0;
 336
 337             inrow  = in ->data[plane];
 338             outrow = out->data[plane];
 339
 340             for (i = 0; i < in->height >> vsub; i ++) {
 341                 for (j = 0; j < inlink->w>>hsub; j++)
 342                     outrow[j] = lut->lut[plane][inrow[j]];
 343                 inrow  += in ->linesize[plane];
 344                 outrow += out->linesize[plane];
 345             }
 346         }
 347     }
 348
 349     av_frame_free(&in);
 350     return ff_filter_frame(outlink, out);
 351 }
 352
 353 static const AVFilterPad inputs[] = {
 354     { .name            = "default",
 355       .type            = AVMEDIA_TYPE_VIDEO,
 356       .filter_frame    = filter_frame,
 357       .config_props    = config_props,
 358     },
 359     { .name = NULL}
 360 };
 361 static const AVFilterPad outputs[] = {
 362     { .name            = "default",
 363       .type            = AVMEDIA_TYPE_VIDEO, },
 364     { .name = NULL}
 365 };
 366 #define DEFINE_LUT_FILTER(name_, description_, init_)                   \
 367     AVFilter avfilter_vf_##name_ = {                                    \
 368         .name          = #name_,                                        \
 369         .description   = NULL_IF_CONFIG_SMALL(description_),            \
 370         .priv_size     = sizeof(LutContext),                            \
 371                                                                         \
 372         .init          = init_,                                         \
 373         .uninit        = uninit,                                        \
 374         .query_formats = query_formats,                                 \
 375                                                                         \
 376         .inputs        = inputs,                                        \
 377         .outputs       = outputs,                                       \
 378     }
 379
 380 #if CONFIG_LUT_FILTER
 381 DEFINE_LUT_FILTER(lut,    "Compute and apply a lookup table to the RGB/YUV input video.", init);
 382 #endif
 383 #if CONFIG_LUTYUV_FILTER
 384 DEFINE_LUT_FILTER(lutyuv, "Compute and apply a lookup table to the YUV input video.",     init);
 385 #endif
 386 #if CONFIG_LUTRGB_FILTER
 387 DEFINE_LUT_FILTER(lutrgb, "Compute and apply a lookup table to the RGB input video.",     init);
 388 #endif
 389
 390 #if CONFIG_NEGATE_FILTER
 391
 392 static int negate_init(AVFilterContext *ctx, const char *args)
 393 {
 394     LutContext *lut = ctx->priv;
 395     char lut_params[64];
 396
 397     if (args)
 398         sscanf(args, "%d", &lut->negate_alpha);
 399
 400     av_log(ctx, AV_LOG_DEBUG, "negate_alpha:%d\n", lut->negate_alpha);
 401
 402     snprintf(lut_params, sizeof(lut_params), "c0=negval:c1=negval:c2=negval:a=%s",
 403              lut->negate_alpha ? "negval" : "val");
 404
 405     return init(ctx, lut_params);
 406 }
 407
 408 DEFINE_LUT_FILTER(negate, "Negate input video.", negate_init);
 409
 410 #endif