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

   1 /*****************************************************************************
   2  * erase.c : logo erase video filter
   3  *****************************************************************************
   4  * Copyright (C) 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 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_sout.h>
  35 #include <vlc_vout.h>
  36 #include "vlc_image.h"
  37
  38 #include "vlc_filter.h"
  39 #include "filter_picture.h"
  40
  41 /*****************************************************************************
  42  * Local prototypes
  43  *****************************************************************************/
  44 static int  Create    ( vlc_object_t * );
  45 static void Destroy   ( vlc_object_t * );
  46
  47 static picture_t *Filter( filter_t *, picture_t * );
  48 static void FilterErase( filter_t *, picture_t *, picture_t * );
  49 static int EraseCallback( vlc_object_t *, char const *,
  50                           vlc_value_t, vlc_value_t, void * );
  51
  52 /*****************************************************************************
  53  * Module descriptor
  54  *****************************************************************************/
  55 #define MASK_TEXT N_("Image mask")
  56 #define MASK_LONGTEXT N_("Image mask. Pixels with an alpha value greater than 50% will be erased.")
  57
  58 #define POSX_TEXT N_("X coordinate")
  59 #define POSX_LONGTEXT N_("X coordinate of the mask.")
  60 #define POSY_TEXT N_("Y coordinate")
  61 #define POSY_LONGTEXT N_("Y coordinate of the mask.")
  62
  63 #define CFG_PREFIX "erase-"
  64
  65 vlc_module_begin ()
  66     set_description( N_("Erase video filter") )
  67     set_shortname( N_( "Erase" ))
  68     set_capability( "video filter2", 0 )
  69     set_category( CAT_VIDEO )
  70     set_subcategory( SUBCAT_VIDEO_VFILTER )
  71
  72     add_file( CFG_PREFIX "mask", NULL, NULL,
  73               MASK_TEXT, MASK_LONGTEXT, false )
  74     add_integer( CFG_PREFIX "x", 0, NULL, POSX_TEXT, POSX_LONGTEXT, false )
  75     add_integer( CFG_PREFIX "y", 0, NULL, POSY_TEXT, POSY_LONGTEXT, false )
  76
  77     add_shortcut( "erase" )
  78     set_callbacks( Create, Destroy )
  79 vlc_module_end ()
  80
  81 static const char *const ppsz_filter_options[] = {
  82     "mask", "x", "y", NULL
  83 };
  84
  85 /*****************************************************************************
  86  * filter_sys_t
  87  *****************************************************************************/
  88 struct filter_sys_t
  89 {
  90     int i_x;
  91     int i_y;
  92     picture_t *p_mask;
  93     vlc_mutex_t lock;
  94 };
  95
  96 static void LoadMask( filter_t *p_filter, const char *psz_filename )
  97 {
  98     image_handler_t *p_image;
  99     video_format_t fmt_in, fmt_out;
 100     picture_t *p_old_mask = p_filter->p_sys->p_mask;
 101     memset( &fmt_in, 0, sizeof( video_format_t ) );
 102     memset( &fmt_out, 0, sizeof( video_format_t ) );
 103     fmt_out.i_chroma = VLC_CODEC_YUVA;
 104     p_image = image_HandlerCreate( p_filter );
 105     p_filter->p_sys->p_mask =
 106         image_ReadUrl( p_image, psz_filename, &fmt_in, &fmt_out );
 107     if( p_filter->p_sys->p_mask )
 108     {
 109         if( p_old_mask )
 110             picture_Release( p_old_mask );
 111     }
 112     else if( p_old_mask )
 113     {
 114         p_filter->p_sys->p_mask = p_old_mask;
 115         msg_Err( p_filter, "Error while loading new mask. Keeping old mask." );
 116     }
 117     image_HandlerDelete( p_image );
 118 }
 119
 120 /*****************************************************************************
 121  * Create
 122  *****************************************************************************/
 123 static int Create( vlc_object_t *p_this )
 124 {
 125     filter_t *p_filter = (filter_t *)p_this;
 126     filter_sys_t *p_sys;
 127     char *psz_filename;
 128
 129     switch( p_filter->fmt_in.video.i_chroma )
 130     {
 131         case VLC_CODEC_I420:
 132         case VLC_CODEC_J420:
 133         case VLC_CODEC_YV12:
 134
 135         case VLC_CODEC_I422:
 136         case VLC_CODEC_J422:
 137             break;
 138
 139         default:
 140             msg_Err( p_filter, "Unsupported input chroma (%4s)",
 141                      (char*)&(p_filter->fmt_in.video.i_chroma) );
 142             return VLC_EGENERIC;
 143     }
 144
 145     /* Allocate structure */
 146     p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
 147     if( p_filter->p_sys == NULL )
 148         return VLC_ENOMEM;
 149     p_sys = p_filter->p_sys;
 150
 151     p_filter->pf_video_filter = Filter;
 152
 153     config_ChainParse( p_filter, CFG_PREFIX, ppsz_filter_options,
 154                        p_filter->p_cfg );
 155
 156     psz_filename =
 157         var_CreateGetNonEmptyStringCommand( p_filter, CFG_PREFIX "mask" );
 158
 159     if( !psz_filename )
 160     {
 161         msg_Err( p_filter, "Missing 'mask' option value." );
 162         return VLC_EGENERIC;
 163     }
 164
 165     p_sys->p_mask = NULL;
 166     LoadMask( p_filter, psz_filename );
 167     free( psz_filename );
 168     p_sys->i_x = var_CreateGetIntegerCommand( p_filter, CFG_PREFIX "x" );
 169     p_sys->i_y = var_CreateGetIntegerCommand( p_filter, CFG_PREFIX "y" );
 170
 171     var_AddCallback( p_filter, CFG_PREFIX "x", EraseCallback, p_sys );
 172     var_AddCallback( p_filter, CFG_PREFIX "y", EraseCallback, p_sys );
 173     var_AddCallback( p_filter, CFG_PREFIX "mask", EraseCallback, p_sys );
 174
 175     vlc_mutex_init( &p_sys->lock );
 176
 177     return VLC_SUCCESS;
 178 }
 179
 180 /*****************************************************************************
 181  * Destroy
 182  *****************************************************************************/
 183 static void Destroy( vlc_object_t *p_this )
 184 {
 185     filter_t *p_filter = (filter_t *)p_this;
 186     filter_sys_t *p_sys = p_filter->p_sys;
 187     if( p_sys->p_mask )
 188         picture_Release( p_sys->p_mask );
 189
 190     vlc_mutex_destroy( &p_sys->lock );
 191
 192     free( p_filter->p_sys );
 193 }
 194
 195 /*****************************************************************************
 196  * Filter
 197  *****************************************************************************/
 198 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 199 {
 200     picture_t *p_outpic;
 201
 202     if( !p_pic ) return NULL;
 203
 204     p_outpic = filter_NewPicture( p_filter );
 205     if( !p_outpic )
 206     {
 207         picture_Release( p_pic );
 208         return NULL;
 209     }
 210
 211     /* Here */
 212     FilterErase( p_filter, p_pic, p_outpic );
 213
 214     return CopyInfoAndRelease( p_outpic, p_pic );
 215 }
 216
 217 /*****************************************************************************
 218  * FilterErase
 219  *****************************************************************************/
 220 static void FilterErase( filter_t *p_filter, picture_t *p_inpic,
 221                                              picture_t *p_outpic )
 222 {
 223     filter_sys_t *p_sys = p_filter->p_sys;
 224
 225     int i_plane;
 226
 227     const int i_mask_pitch = p_sys->p_mask->A_PITCH;
 228     const int i_mask_visible_pitch = p_sys->p_mask->p[A_PLANE].i_visible_pitch;
 229     const int i_mask_visible_lines = p_sys->p_mask->p[A_PLANE].i_visible_lines;
 230
 231     for( i_plane = 0; i_plane < p_inpic->i_planes; i_plane++ )
 232     {
 233         const int i_pitch = p_inpic->p[i_plane].i_pitch;
 234         const int i_2pitch = i_pitch<<1;
 235         const int i_visible_pitch = p_inpic->p[i_plane].i_visible_pitch;
 236         const int i_lines = p_inpic->p[i_plane].i_lines;
 237         const int i_visible_lines = p_inpic->p[i_plane].i_visible_lines;
 238
 239         uint8_t *p_inpix = p_inpic->p[i_plane].p_pixels;
 240         uint8_t *p_outpix = p_outpic->p[i_plane].p_pixels;
 241         uint8_t *p_mask = p_sys->p_mask->A_PIXELS;
 242
 243         int i_x = p_sys->i_x,
 244             i_y = p_sys->i_y;
 245         int x, y;
 246         int i_height = i_mask_visible_lines;
 247         int i_width  = i_mask_visible_pitch;
 248
 249         const bool b_line_factor = ( i_plane /* U_PLANE or V_PLANE */ &&
 250             !( p_inpic->format.i_chroma == VLC_CODEC_I422
 251             || p_inpic->format.i_chroma == VLC_CODEC_J422 ) );
 252
 253         if( i_plane ) /* U_PLANE or V_PLANE */
 254         {
 255             i_width  >>= 1;
 256             i_x      >>= 1;
 257         }
 258         if( b_line_factor )
 259         {
 260             i_height >>= 1;
 261             i_y      >>= 1;
 262         }
 263         i_height = __MIN( i_visible_lines - i_y, i_height );
 264         i_width  = __MIN( i_visible_pitch - i_x, i_width  );
 265
 266         /* Copy original pixel buffer */
 267         vlc_memcpy( p_outpix, p_inpix, i_pitch * i_lines );
 268
 269         /* Horizontal linear interpolation of masked areas */
 270         p_outpix = p_outpic->p[i_plane].p_pixels + i_y*i_pitch + i_x;
 271         for( y = 0; y < i_height;
 272              y++, p_mask += i_mask_pitch, p_outpix += i_pitch )
 273         {
 274             uint8_t prev, next = 0;
 275             int prev_x = -1, next_x = -2;
 276             int quot = 0;
 277
 278             /* Find a suitable value for the previous color to use when
 279              * interpoling a masked pixel's value */
 280             if( i_x )
 281             {
 282                 /* There are pixels before current position on the same line.
 283                  * Use those */
 284                 prev = *(p_outpix-1);
 285             }
 286             else if( y || i_y )
 287             {
 288                 /* This is the first pixel on a line but there other lines
 289                  * above us. Use the pixel right above */
 290                 prev = *(p_outpix-i_pitch);
 291             }
 292             else
 293             {
 294                 /* We're in the upper left corner. This sucks. We can't use
 295                  * any previous value, so we'll use a dummy one. In most
 296                  * cases this dummy value will be fixed later on in the
 297                  * algorithm */
 298                 prev = 0xff;
 299             }
 300
 301             for( x = 0; x < i_width; x++ )
 302             {
 303                 if( p_mask[i_plane?x<<1:x] > 127 )
 304                 {
 305                     /* This is a masked pixel */
 306                     if( next_x <= prev_x )
 307                     {
 308                         int x0;
 309                         /* Look for the next non masked pixel on the same
 310                          * line (inside the mask's bounding box) */
 311                         for( x0 = x; x0 < i_width; x0++ )
 312                         {
 313                             if( p_mask[i_plane?x0<<1:x0] <= 127 )
 314                             {
 315                                 /* We found an unmasked pixel. Victory! */
 316                                 next_x = x0;
 317                                 next = p_outpix[x0];
 318                                 break;
 319                             }
 320                         }
 321                         if( next_x <= prev_x )
 322                         {
 323                             /* We didn't find an unmasked pixel yet. Try
 324                              * harder */
 325                             if( x0 == x ) x0++;
 326                             if( x0 < i_visible_pitch )
 327                             {
 328                                 /* If we didn't find a non masked pixel on the
 329                                  * same line inside the mask's bounding box,
 330                                  * use the next pixel on the line (except if
 331                                  * it doesn't exist) */
 332                                 next_x = x0;
 333                                 next = p_outpix[x0];
 334                             }
 335                             else
 336                             {
 337                                 /* The last pixel on the line is masked,
 338                                  * so we'll use the "prev" value. A better
 339                                  * approach would be to use unmasked pixels
 340                                  * at the end of adjacent lines */
 341                                 next_x = x0;
 342                                 next = prev;
 343                             }
 344                         }
 345                         if( !( i_x || y || i_y ) )
 346                             /* We were unable to find a suitable value for
 347                              * the previous color (which means that we are
 348                              * on the first line in the upper left corner)
 349                              */
 350                             prev = next;
 351
 352                         /* Divide only once instead of next_x-prev_x-1 times */
 353                         quot = ((next-prev)<<16)/(next_x-prev_x);
 354                     }
 355                     /* Interpolate new value, and round correctly */
 356                     p_outpix[x] = prev + (((x-prev_x)*quot+(1<<16))>>16);
 357                 }
 358                 else
 359                 {
 360                     /* This pixel isn't masked. It's thus suitable as a
 361                      * previous color for the next interpolation */
 362                     prev = p_outpix[x];
 363                     prev_x = x;
 364                 }
 365             }
 366         }
 367
 368         /* Vertical bluring */
 369         p_mask = p_sys->p_mask->A_PIXELS;
 370         i_height = b_line_factor ? i_mask_visible_lines>>1
 371                                  : i_mask_visible_lines;
 372         /* Make sure that we stop at least 2 lines before the picture's end
 373          * (since our bluring algorithm uses the 2 next lines) */
 374         i_height = __MIN( i_visible_lines - i_y - 2, i_height );
 375         /* Make sure that we start at least 2 lines from the top (since our
 376          * bluring algorithm uses the 2 previous lines) */
 377         y = __MAX(i_y,2);
 378         p_outpix = p_outpic->p[i_plane].p_pixels + (i_y+y)*i_pitch + i_x;
 379         for( ; y < i_height; y++, p_mask += i_mask_pitch, p_outpix += i_pitch )
 380         {
 381             for( x = 0; x < i_width; x++ )
 382             {
 383                 if( p_mask[i_plane?x<<1:x] > 127 )
 384                 {
 385                     /* Ugly bluring function */
 386                     p_outpix[x] =
 387                         ( (p_outpix[x-i_2pitch]<<1)       /* 2 */
 388                         + (p_outpix[x-i_pitch ]<<2)       /* 4 */
 389                         + (p_outpix[x         ]<<2)       /* 4 */
 390                         + (p_outpix[x+i_pitch ]<<2)       /* 4 */
 391                         + (p_outpix[x+i_2pitch]<<1) )>>4; /* 2 */
 392                 }
 393             }
 394         }
 395     }
 396 }
 397
 398 static int EraseCallback( vlc_object_t *p_this, char const *psz_var,
 399                           vlc_value_t oldval, vlc_value_t newval, void *p_data )
 400 {
 401     VLC_UNUSED(oldval);
 402     filter_sys_t *p_sys = (filter_sys_t *)p_data;
 403
 404     if( !strcmp( psz_var, CFG_PREFIX "x" ) )
 405     {
 406         vlc_mutex_lock( &p_sys->lock );
 407         p_sys->i_x = newval.i_int;
 408         vlc_mutex_unlock( &p_sys->lock );
 409     }
 410     else if( !strcmp( psz_var, CFG_PREFIX "y" ) )
 411     {
 412         vlc_mutex_lock( &p_sys->lock );
 413         p_sys->i_y = newval.i_int;
 414         vlc_mutex_unlock( &p_sys->lock );
 415     }
 416     else if( !strcmp( psz_var, CFG_PREFIX "mask" ) )
 417     {
 418         vlc_mutex_lock( &p_sys->lock );
 419         LoadMask( (filter_t*)p_this, newval.psz_string );
 420         vlc_mutex_unlock( &p_sys->lock );
 421     }
 422     else
 423     {
 424         msg_Warn( p_this, "Unknown callback command." );
 425     }
 426     return VLC_SUCCESS;
 427 }