git.sesse.net Git - vlc/blob - modules/video_filter/gaussianblur.c

   1 /*****************************************************************************
   2  * gaussianblur.c : gaussian blur video filter
   3  *****************************************************************************
   4  * Copyright (C) 2000-2007 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Antoine Cellerier <dionoea -at- videolan -dot- org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27
  28 #include <vlc/vlc.h>
  29 #include <vlc_vout.h>
  30
  31 #include "vlc_filter.h"
  32
  33 #include <math.h>                                          /* exp(), sqrt() */
  34
  35 /*****************************************************************************
  36  * Local prototypes
  37  *****************************************************************************/
  38 static int  Create    ( vlc_object_t * );
  39 static void Destroy   ( vlc_object_t * );
  40
  41 static picture_t *Filter( filter_t *, picture_t * );
  42
  43 #define SIGMA_TEXT N_("Gaussian's std deviation")
  44 #define SIGMA_LONGTEXT N_( \
  45     "Gaussian's standard deviation. The bluring will take " \
  46     "into account pixels up to 3*sigma away in any direction.")
  47
  48 #define FILTER_PREFIX "gaussianblur-"
  49
  50 /*****************************************************************************
  51  * Module descriptor
  52  *****************************************************************************/
  53 vlc_module_begin();
  54     set_description( _("Gaussian blur video filter") );
  55     set_shortname( _( "Gaussian Blur" ));
  56     set_capability( "video filter2", 0 );
  57     set_category( CAT_VIDEO );
  58     set_subcategory( SUBCAT_VIDEO_VFILTER );
  59
  60     add_float( FILTER_PREFIX "sigma", 2., NULL, SIGMA_TEXT, SIGMA_LONGTEXT,
  61                VLC_FALSE );
  62
  63     set_callbacks( Create, Destroy );
  64 vlc_module_end();
  65
  66 static const char *ppsz_filter_options[] = {
  67     "sigma", NULL
  68 };
  69
  70 /* Comment this to use floats instead of integers (faster for bigger sigma
  71  * values)
  72  * For sigma = 2 ints are faster
  73  * For sigma = 4 floats are faster
  74  */
  75 #define DONT_USE_FLOATS
  76 struct filter_sys_t
  77 {
  78     double f_sigma;
  79     int i_dim;
  80 #ifdef DONT_USE_FLOATS
  81     int *pi_distribution;
  82     int *pi_buffer;
  83     int *pi_scale;
  84 #else
  85     float *pf_distribution;
  86     float *pf_buffer;
  87     float *pf_scale;
  88 #endif
  89 };
  90
  91 static void gaussianblur_InitDistribution( filter_sys_t *p_sys )
  92 {
  93     double f_sigma = p_sys->f_sigma;
  94     int i_dim = (int)(3.*f_sigma);
  95 #ifdef DONT_USE_FLOATS
  96     int *pi_distribution = (int*)malloc( (2*i_dim+1) * sizeof( int ) );
  97 #else
  98     float *pf_distribution = (float*)malloc( (2*i_dim+1) * sizeof( float ) );
  99 #endif
 100     int x;
 101     for( x = -i_dim; x <= i_dim; x++ )
 102     {
 103 #ifdef DONT_USE_FLOATS
 104         pi_distribution[i_dim+x] =
 105             (int)( sqrt( exp(-(x*x)/(f_sigma*f_sigma) )
 106                  / (2.*M_PI*f_sigma*f_sigma) )  * (double)(1<<8) );
 107         printf("%d\n",pi_distribution[i_dim+x]);
 108 #else
 109         pf_distribution[i_dim+x] = (float)
 110             sqrt( exp(-(x*x)/(f_sigma*f_sigma) ) / (2.*M_PI*f_sigma*f_sigma) );
 111         printf("%f\n",pf_distribution[i_dim+x]);
 112 #endif
 113     }
 114     p_sys->i_dim = i_dim;
 115 #ifdef DONT_USE_FLOATS
 116     p_sys->pi_distribution = pi_distribution;
 117 #else
 118     p_sys->pf_distribution = pf_distribution;
 119 #endif
 120 }
 121
 122 static int Create( vlc_object_t *p_this )
 123 {
 124     filter_t *p_filter = (filter_t *)p_this;
 125
 126     p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
 127     if( p_filter->p_sys == NULL )
 128     {
 129         msg_Err( p_filter, "out of memory" );
 130         return VLC_ENOMEM;
 131     }
 132
 133     config_ChainParse( p_filter, FILTER_PREFIX, ppsz_filter_options,
 134                        p_filter->p_cfg );
 135
 136     p_filter->pf_video_filter = Filter;
 137
 138     p_filter->p_sys->f_sigma =
 139         var_CreateGetFloat( p_filter, FILTER_PREFIX "sigma" );
 140     if( p_filter->p_sys->f_sigma <= 0. )
 141     {
 142         msg_Err( p_filter, "sigma must be positive" );
 143         return VLC_EGENERIC;
 144     }
 145     gaussianblur_InitDistribution( p_filter->p_sys );
 146     msg_Dbg( p_filter, "gaussian distribution is %d pixels wide",
 147              p_filter->p_sys->i_dim*2+1 );
 148 #ifdef DONT_USE_FLOATS
 149     p_filter->p_sys->pi_buffer = NULL;
 150     p_filter->p_sys->pi_scale = NULL;
 151 #else
 152     p_filter->p_sys->pf_buffer = NULL;
 153     p_filter->p_sys->pf_scale = NULL;
 154 #endif
 155
 156     return VLC_SUCCESS;
 157 }
 158
 159 static void Destroy( vlc_object_t *p_this )
 160 {
 161     filter_t *p_filter = (filter_t *)p_this;
 162 #ifdef DONT_USE_FLOATS
 163     free( p_filter->p_sys->pi_distribution );
 164     free( p_filter->p_sys->pi_buffer );
 165     free( p_filter->p_sys->pi_scale );
 166 #else
 167     free( p_filter->p_sys->pf_distribution );
 168     free( p_filter->p_sys->pf_buffer );
 169     free( p_filter->p_sys->pf_scale );
 170 #endif
 171     free( p_filter->p_sys );
 172 }
 173
 174 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 175 {
 176     picture_t *p_outpic;
 177     filter_sys_t *p_sys = p_filter->p_sys;
 178     int i_plane;
 179     const int i_dim = p_sys->i_dim;
 180 #ifdef DONT_USE_FLOATS
 181     int *pi_buffer;
 182     int *pi_scale;
 183     const int *pi_distribution = p_sys->pi_distribution;
 184 #else
 185     float *pf_buffer;
 186     float *pf_scale;
 187     const float *pf_distribution = p_sys->pf_distribution;
 188 #endif
 189     if( !p_pic ) return NULL;
 190
 191     p_outpic = p_filter->pf_vout_buffer_new( p_filter );
 192     if( !p_outpic )
 193     {
 194         msg_Warn( p_filter, "can't get output picture" );
 195         if( p_pic->pf_release )
 196             p_pic->pf_release( p_pic );
 197         return NULL;
 198     }
 199 #ifdef DONT_USE_FLOATS
 200     if( !p_sys->pi_buffer )
 201     {
 202         p_sys->pi_buffer = (int*)realloc( p_sys->pi_buffer,
 203                                           p_pic->p[Y_PLANE].i_visible_lines
 204                                           * p_pic->p[Y_PLANE].i_pitch
 205                                           * sizeof( int ) );
 206     }
 207     pi_buffer = p_sys->pi_buffer;
 208 #else
 209     if( !p_sys->pf_buffer )
 210     {
 211         p_sys->pf_buffer = (float*)realloc( p_sys->pf_buffer,
 212                                             p_pic->p[Y_PLANE].i_visible_lines
 213                                             * p_pic->p[Y_PLANE].i_pitch
 214                                             * sizeof( float ) );
 215     }
 216     pf_buffer = p_sys->pf_buffer;
 217 #endif
 218 #ifdef DONT_USE_FLOATS
 219     if( !p_sys->pi_scale )
 220 #else
 221     if( !p_sys->pf_scale )
 222 #endif
 223     {
 224         const int i_visible_lines = p_pic->p[Y_PLANE].i_visible_lines;
 225         const int i_visible_pitch = p_pic->p[Y_PLANE].i_visible_pitch;
 226         const int i_pitch = p_pic->p[Y_PLANE].i_pitch;
 227         int i_col, i_line;
 228 #ifdef DONT_USE_FLOATS
 229         p_sys->pi_scale = (int*)malloc( i_visible_lines * i_pitch
 230                                         * sizeof( int ) );
 231         pi_scale = p_sys->pi_scale;
 232 #else
 233         p_sys->pf_scale = (float*)malloc( i_visible_lines * i_pitch
 234                                           * sizeof( float ) );
 235         pf_scale = p_sys->pf_scale;
 236 #endif
 237         for( i_line = 0 ; i_line < i_visible_lines ; i_line++ )
 238         {
 239             for( i_col = 0; i_col < i_visible_pitch ; i_col++ )
 240             {
 241                 int x, y;
 242 #ifdef DONT_USE_FLOATS
 243                 int value = 0;
 244 #else
 245                 double value = 0.;
 246 #endif
 247                 for( y = __MAX( -i_dim, -i_line );
 248                      y <= __MIN( i_dim, i_visible_lines - i_line - 1 );
 249                      y++ )
 250                 {
 251                     for( x = __MAX( -i_dim, -i_col );
 252                          x <= __MIN( i_dim, i_visible_pitch - i_col + 1 );
 253                          x++ )
 254                     {
 255 #ifdef DONT_USE_FLOATS
 256                         value += pi_distribution[y+i_dim]
 257                                * pi_distribution[x+i_dim];
 258 #else
 259                         value += ((double)pf_distribution[y+i_dim])
 260                                * ((double)pf_distribution[x+i_dim]);
 261 #endif
 262                     }
 263                 }
 264 #ifdef DONT_USE_FLOATS
 265                 pi_scale[i_line*i_pitch+i_col] = value;
 266 #else
 267                 pf_scale[i_line*i_pitch+i_col] = (float)(1./value);
 268 #endif
 269             }
 270         }
 271     }
 272 #ifdef DONT_USE_FLOATS
 273     pi_scale = p_sys->pi_scale;
 274 #else
 275     pf_scale = p_sys->pf_scale;
 276 #endif
 277
 278     for( i_plane = 0 ; i_plane < p_pic->i_planes ; i_plane++ )
 279     {
 280
 281         uint8_t *p_in = p_pic->p[i_plane].p_pixels;
 282         uint8_t *p_out = p_outpic->p[i_plane].p_pixels;
 283
 284         const int i_visible_lines = p_pic->p[i_plane].i_visible_lines;
 285         const int i_visible_pitch = p_pic->p[i_plane].i_visible_pitch;
 286         const int i_pitch = p_pic->p[i_plane].i_pitch;
 287
 288         int i_line, i_col;
 289         const int factor = i_plane ? 1 : 0;
 290
 291         for( i_line = 0 ; i_line < i_visible_lines ; i_line++ )
 292         {
 293             for( i_col = 0; i_col < i_visible_pitch ; i_col++ )
 294             {
 295 #ifdef DONT_USE_FLOATS
 296                 int value = 0;
 297 #else
 298                 float value = 0.;
 299 #endif
 300                 int x;
 301                 const int c = i_line*i_pitch+i_col;
 302                 for( x = __MAX( -i_dim, -i_col*(factor+1) );
 303                      x <= __MIN( i_dim, (i_visible_pitch - i_col)*(factor+1) + 1 );
 304                      x++ )
 305                 {
 306 #ifdef DONT_USE_FLOATS
 307                     value += pi_distribution[x+i_dim]
 308                            * p_in[c+(x>>factor)];
 309 #else
 310                     value += pf_distribution[x+i_dim]
 311                            * (float)p_in[c+(x>>factor)];
 312 #endif
 313                 }
 314 #ifdef DONT_USE_FLOATS
 315                 pi_buffer[c] = value;
 316 #else
 317                 pf_buffer[c] = value;
 318 #endif
 319             }
 320         }
 321         for( i_line = 0 ; i_line < i_visible_lines ; i_line++ )
 322         {
 323             for( i_col = 0; i_col < i_visible_pitch ; i_col++ )
 324             {
 325 #ifdef DONT_USE_FLOATS
 326                 int value = 0;
 327 #else
 328                 float value = 0.;
 329 #endif
 330                 int y;
 331                 const int c = i_line*i_pitch+i_col;
 332                 for( y = __MAX( -i_dim, (-i_line)*(factor+1) );
 333                      y <= __MIN( i_dim, (i_visible_lines - i_line)*(factor+1) - 1 );
 334                      y++ )
 335                 {
 336 #ifdef DONT_USE_FLOATS
 337                     value += pi_distribution[y+i_dim]
 338                            * pi_buffer[c+(y>>factor)*i_pitch];
 339 #else
 340                     value += pf_distribution[y+i_dim]
 341                            * pf_buffer[c+(y>>factor)*i_pitch];
 342 #endif
 343                 }
 344 #ifdef DONT_USE_FLOATS
 345                 p_out[c] = (uint8_t)(value/pi_scale[(i_line<<factor)*(i_pitch<<factor)+(i_col<<factor)]);
 346 #else
 347                 p_out[c] = (uint8_t)(value*pf_scale[(i_line<<factor)*(i_pitch<<factor)+(i_col<<factor)]);
 348 #endif
 349             }
 350         }
 351     }
 352
 353     p_outpic->date = p_pic->date;
 354     p_outpic->b_force = p_pic->b_force;
 355     p_outpic->i_nb_fields = p_pic->i_nb_fields;
 356     p_outpic->b_progressive = p_pic->b_progressive;
 357     p_outpic->b_top_field_first = p_pic->b_top_field_first;
 358
 359     if( p_pic->pf_release )
 360         p_pic->pf_release( p_pic );
 361
 362     return p_outpic;
 363 }