libavfilter/vf_lut.c
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00001 /*
00002  * Copyright (c) 2011 Stefano Sabatini
00003  *
00004  * This file is part of Libav.
00005  *
00006  * Libav is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * Libav is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with Libav; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00027 #include "libavutil/eval.h"
00028 #include "libavutil/mathematics.h"
00029 #include "libavutil/opt.h"
00030 #include "libavutil/pixdesc.h"
00031 #include "avfilter.h"
00032 #include "internal.h"
00033 
00034 static const char *var_names[] = {
00035     "E",
00036     "PHI",
00037     "PI",
00038     "w",        
00039     "h",        
00040     "val",      
00041     "maxval",   
00042     "minval",   
00043     "negval",   
00044     "clipval",
00045     NULL
00046 };
00047 
00048 enum var_name {
00049     VAR_E,
00050     VAR_PHI,
00051     VAR_PI,
00052     VAR_W,
00053     VAR_H,
00054     VAR_VAL,
00055     VAR_MAXVAL,
00056     VAR_MINVAL,
00057     VAR_NEGVAL,
00058     VAR_CLIPVAL,
00059     VAR_VARS_NB
00060 };
00061 
00062 typedef struct {
00063     const AVClass *class;
00064     uint8_t lut[4][256];  
00065     char   *comp_expr_str[4];
00066     AVExpr *comp_expr[4];
00067     int hsub, vsub;
00068     double var_values[VAR_VARS_NB];
00069     int is_rgb, is_yuv;
00070     int rgba_map[4];
00071     int step;
00072     int negate_alpha; /* only used by negate */
00073 } LutContext;
00074 
00075 #define Y 0
00076 #define U 1
00077 #define V 2
00078 #define R 0
00079 #define G 1
00080 #define B 2
00081 #define A 3
00082 
00083 #define OFFSET(x) offsetof(LutContext, x)
00084 
00085 static const AVOption lut_options[] = {
00086     {"c0", "set component #0 expression", OFFSET(comp_expr_str[0]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00087     {"c1", "set component #1 expression", OFFSET(comp_expr_str[1]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00088     {"c2", "set component #2 expression", OFFSET(comp_expr_str[2]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00089     {"c3", "set component #3 expression", OFFSET(comp_expr_str[3]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00090     {"y",  "set Y expression", OFFSET(comp_expr_str[Y]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00091     {"u",  "set U expression", OFFSET(comp_expr_str[U]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00092     {"v",  "set V expression", OFFSET(comp_expr_str[V]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00093     {"r",  "set R expression", OFFSET(comp_expr_str[R]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00094     {"g",  "set G expression", OFFSET(comp_expr_str[G]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00095     {"b",  "set B expression", OFFSET(comp_expr_str[B]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00096     {"a",  "set A expression", OFFSET(comp_expr_str[A]),  FF_OPT_TYPE_STRING, {.str="val"}, CHAR_MIN, CHAR_MAX},
00097     {NULL},
00098 };
00099 
00100 static const char *lut_get_name(void *ctx)
00101 {
00102     return "lut";
00103 }
00104 
00105 static const AVClass lut_class = {
00106     "LutContext",
00107     lut_get_name,
00108     lut_options
00109 };
00110 
00111 static int init(AVFilterContext *ctx, const char *args, void *opaque)
00112 {
00113     LutContext *lut = ctx->priv;
00114     int ret;
00115 
00116     lut->class = &lut_class;
00117     av_opt_set_defaults(lut);
00118 
00119     lut->var_values[VAR_PHI] = M_PHI;
00120     lut->var_values[VAR_PI]  = M_PI;
00121     lut->var_values[VAR_E ]  = M_E;
00122 
00123     lut->is_rgb = !strcmp(ctx->filter->name, "lutrgb");
00124     lut->is_yuv = !strcmp(ctx->filter->name, "lutyuv");
00125     if (args && (ret = av_set_options_string(lut, args, "=", ":")) < 0)
00126         return ret;
00127 
00128     return 0;
00129 }
00130 
00131 static av_cold void uninit(AVFilterContext *ctx)
00132 {
00133     LutContext *lut = ctx->priv;
00134     int i;
00135 
00136     for (i = 0; i < 4; i++) {
00137         av_expr_free(lut->comp_expr[i]);
00138         lut->comp_expr[i] = NULL;
00139         av_freep(&lut->comp_expr_str[i]);
00140     }
00141 }
00142 
00143 #define YUV_FORMATS                                         \
00144     PIX_FMT_YUV444P,  PIX_FMT_YUV422P,  PIX_FMT_YUV420P,    \
00145     PIX_FMT_YUV411P,  PIX_FMT_YUV410P,  PIX_FMT_YUV440P,    \
00146     PIX_FMT_YUVA420P,                                       \
00147     PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P,   \
00148     PIX_FMT_YUVJ440P
00149 
00150 #define RGB_FORMATS                             \
00151     PIX_FMT_ARGB,         PIX_FMT_RGBA,         \
00152     PIX_FMT_ABGR,         PIX_FMT_BGRA,         \
00153     PIX_FMT_RGB24,        PIX_FMT_BGR24
00154 
00155 static enum PixelFormat yuv_pix_fmts[] = { YUV_FORMATS, PIX_FMT_NONE };
00156 static enum PixelFormat rgb_pix_fmts[] = { RGB_FORMATS, PIX_FMT_NONE };
00157 static enum PixelFormat all_pix_fmts[] = { RGB_FORMATS, YUV_FORMATS, PIX_FMT_NONE };
00158 
00159 static int query_formats(AVFilterContext *ctx)
00160 {
00161     LutContext *lut = ctx->priv;
00162 
00163     enum PixelFormat *pix_fmts = lut->is_rgb ? rgb_pix_fmts :
00164                                  lut->is_yuv ? yuv_pix_fmts : all_pix_fmts;
00165 
00166     avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
00167     return 0;
00168 }
00169 
00173 static double clip(void *opaque, double val)
00174 {
00175     LutContext *lut = opaque;
00176     double minval = lut->var_values[VAR_MINVAL];
00177     double maxval = lut->var_values[VAR_MAXVAL];
00178 
00179     return av_clip(val, minval, maxval);
00180 }
00181 
00186 static double compute_gammaval(void *opaque, double gamma)
00187 {
00188     LutContext *lut = opaque;
00189     double val    = lut->var_values[VAR_CLIPVAL];
00190     double minval = lut->var_values[VAR_MINVAL];
00191     double maxval = lut->var_values[VAR_MAXVAL];
00192 
00193     return pow((val-minval)/(maxval-minval), gamma) * (maxval-minval)+minval;
00194 }
00195 
00196 static double (* const funcs1[])(void *, double) = {
00197     clip,
00198     compute_gammaval,
00199     NULL
00200 };
00201 
00202 static const char * const funcs1_names[] = {
00203     "clip",
00204     "gammaval",
00205     NULL
00206 };
00207 
00208 static int config_props(AVFilterLink *inlink)
00209 {
00210     AVFilterContext *ctx = inlink->dst;
00211     LutContext *lut = ctx->priv;
00212     const AVPixFmtDescriptor *desc = &av_pix_fmt_descriptors[inlink->format];
00213     int min[4], max[4];
00214     int val, comp, ret;
00215 
00216     lut->hsub = desc->log2_chroma_w;
00217     lut->vsub = desc->log2_chroma_h;
00218 
00219     lut->var_values[VAR_W] = inlink->w;
00220     lut->var_values[VAR_H] = inlink->h;
00221 
00222     switch (inlink->format) {
00223     case PIX_FMT_YUV410P:
00224     case PIX_FMT_YUV411P:
00225     case PIX_FMT_YUV420P:
00226     case PIX_FMT_YUV422P:
00227     case PIX_FMT_YUV440P:
00228     case PIX_FMT_YUV444P:
00229     case PIX_FMT_YUVA420P:
00230         min[Y] = min[U] = min[V] = 16;
00231         max[Y] = 235;
00232         max[U] = max[V] = 240;
00233         min[A] = 0; max[A] = 255;
00234         break;
00235     default:
00236         min[0] = min[1] = min[2] = min[3] = 0;
00237         max[0] = max[1] = max[2] = max[3] = 255;
00238     }
00239 
00240     lut->is_yuv = lut->is_rgb = 0;
00241     if      (ff_fmt_is_in(inlink->format, yuv_pix_fmts)) lut->is_yuv = 1;
00242     else if (ff_fmt_is_in(inlink->format, rgb_pix_fmts)) lut->is_rgb = 1;
00243 
00244     if (lut->is_rgb) {
00245         switch (inlink->format) {
00246         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;
00247         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;
00248         case PIX_FMT_RGBA:
00249         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;
00250         case PIX_FMT_BGRA:
00251         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;
00252         }
00253         lut->step = av_get_bits_per_pixel(desc) >> 3;
00254     }
00255 
00256     for (comp = 0; comp < desc->nb_components; comp++) {
00257         double res;
00258 
00259         /* create the parsed expression */
00260         ret = av_expr_parse(&lut->comp_expr[comp], lut->comp_expr_str[comp],
00261                             var_names, funcs1_names, funcs1, NULL, NULL, 0, ctx);
00262         if (ret < 0) {
00263             av_log(ctx, AV_LOG_ERROR,
00264                    "Error when parsing the expression '%s' for the component %d.\n",
00265                    lut->comp_expr_str[comp], comp);
00266             return AVERROR(EINVAL);
00267         }
00268 
00269         /* compute the lut */
00270         lut->var_values[VAR_MAXVAL] = max[comp];
00271         lut->var_values[VAR_MINVAL] = min[comp];
00272 
00273         for (val = 0; val < 256; val++) {
00274             lut->var_values[VAR_VAL] = val;
00275             lut->var_values[VAR_CLIPVAL] = av_clip(val, min[comp], max[comp]);
00276             lut->var_values[VAR_NEGVAL] =
00277                 av_clip(min[comp] + max[comp] - lut->var_values[VAR_VAL],
00278                         min[comp], max[comp]);
00279 
00280             res = av_expr_eval(lut->comp_expr[comp], lut->var_values, lut);
00281             if (isnan(res)) {
00282                 av_log(ctx, AV_LOG_ERROR,
00283                        "Error when evaluating the expression '%s' for the value %d for the component #%d.\n",
00284                        lut->comp_expr_str[comp], val, comp);
00285                 return AVERROR(EINVAL);
00286             }
00287             lut->lut[comp][val] = av_clip((int)res, min[comp], max[comp]);
00288             av_log(ctx, AV_LOG_DEBUG, "val[%d][%d] = %d\n", comp, val, lut->lut[comp][val]);
00289         }
00290     }
00291 
00292     return 0;
00293 }
00294 
00295 static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
00296 {
00297     AVFilterContext *ctx = inlink->dst;
00298     LutContext *lut = ctx->priv;
00299     AVFilterLink *outlink = ctx->outputs[0];
00300     AVFilterBufferRef *inpic  = inlink ->cur_buf;
00301     AVFilterBufferRef *outpic = outlink->out_buf;
00302     uint8_t *inrow, *outrow, *inrow0, *outrow0;
00303     int i, j, k, plane;
00304 
00305     if (lut->is_rgb) {
00306         /* packed */
00307         inrow0  = inpic ->data[0] + y * inpic ->linesize[0];
00308         outrow0 = outpic->data[0] + y * outpic->linesize[0];
00309 
00310         for (i = 0; i < h; i ++) {
00311             inrow  = inrow0;
00312             outrow = outrow0;
00313             for (j = 0; j < inlink->w; j++) {
00314                 for (k = 0; k < lut->step; k++)
00315                     outrow[k] = lut->lut[lut->rgba_map[k]][inrow[k]];
00316                 outrow += lut->step;
00317                 inrow  += lut->step;
00318             }
00319             inrow0  += inpic ->linesize[0];
00320             outrow0 += outpic->linesize[0];
00321         }
00322     } else {
00323         /* planar */
00324         for (plane = 0; plane < 4 && inpic->data[plane]; plane++) {
00325             int vsub = plane == 1 || plane == 2 ? lut->vsub : 0;
00326             int hsub = plane == 1 || plane == 2 ? lut->hsub : 0;
00327 
00328             inrow  = inpic ->data[plane] + (y>>vsub) * inpic ->linesize[plane];
00329             outrow = outpic->data[plane] + (y>>vsub) * outpic->linesize[plane];
00330 
00331             for (i = 0; i < h>>vsub; i ++) {
00332                 for (j = 0; j < inlink->w>>hsub; j++)
00333                     outrow[j] = lut->lut[plane][inrow[j]];
00334                 inrow  += inpic ->linesize[plane];
00335                 outrow += outpic->linesize[plane];
00336             }
00337         }
00338     }
00339 
00340     avfilter_draw_slice(outlink, y, h, slice_dir);
00341 }
00342 
00343 #define DEFINE_LUT_FILTER(name_, description_, init_)                   \
00344     AVFilter avfilter_vf_##name_ = {                                    \
00345         .name          = #name_,                                        \
00346         .description   = NULL_IF_CONFIG_SMALL(description_),            \
00347         .priv_size     = sizeof(LutContext),                            \
00348                                                                         \
00349         .init          = init_,                                         \
00350         .uninit        = uninit,                                        \
00351         .query_formats = query_formats,                                 \
00352                                                                         \
00353         .inputs    = (AVFilterPad[]) {{ .name            = "default",   \
00354                                         .type            = AVMEDIA_TYPE_VIDEO, \
00355                                         .draw_slice      = draw_slice,  \
00356                                         .config_props    = config_props, \
00357                                         .min_perms       = AV_PERM_READ, }, \
00358                                       { .name = NULL}},                 \
00359         .outputs   = (AVFilterPad[]) {{ .name            = "default",   \
00360                                         .type            = AVMEDIA_TYPE_VIDEO, }, \
00361                                       { .name = NULL}},                 \
00362     }
00363 
00364 #if CONFIG_LUT_FILTER
00365 DEFINE_LUT_FILTER(lut,    "Compute and apply a lookup table to the RGB/YUV input video.", init);
00366 #endif
00367 #if CONFIG_LUTYUV_FILTER
00368 DEFINE_LUT_FILTER(lutyuv, "Compute and apply a lookup table to the YUV input video.",     init);
00369 #endif
00370 #if CONFIG_LUTRGB_FILTER
00371 DEFINE_LUT_FILTER(lutrgb, "Compute and apply a lookup table to the RGB input video.",     init);
00372 #endif
00373 
00374 #if CONFIG_NEGATE_FILTER
00375 
00376 static int negate_init(AVFilterContext *ctx, const char *args, void *opaque)
00377 {
00378     LutContext *lut = ctx->priv;
00379     char lut_params[64];
00380 
00381     if (args)
00382         sscanf(args, "%d", &lut->negate_alpha);
00383 
00384     av_log(ctx, AV_LOG_DEBUG, "negate_alpha:%d\n", lut->negate_alpha);
00385 
00386     snprintf(lut_params, sizeof(lut_params), "c0=negval:c1=negval:c2=negval:a=%s",
00387              lut->negate_alpha ? "negval" : "val");
00388 
00389     return init(ctx, lut_params, opaque);
00390 }
00391 
00392 DEFINE_LUT_FILTER(negate, "Negate input video.", negate_init);
00393 
00394 #endif