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_image.h>
  36
  37 #include <vlc_filter.h>
  38 #include "filter_picture.h"
  39
  40 /*****************************************************************************
  41  * Local prototypes
  42  *****************************************************************************/
  43 static int  Create    ( vlc_object_t * );
  44 static void Destroy   ( vlc_object_t * );
  45
  46 static picture_t *Filter( filter_t *, picture_t * );
  47 static void FilterErase( filter_t *, picture_t *, picture_t * );
  48 static int EraseCallback( vlc_object_t *, char const *,
  49                           vlc_value_t, vlc_value_t, void * );
  50
  51 /*****************************************************************************
  52  * Module descriptor
  53  *****************************************************************************/
  54 #define MASK_TEXT N_("Image mask")
  55 #define MASK_LONGTEXT N_("Image mask. Pixels with an alpha value greater than 50% will be erased.")
  56
  57 #define POSX_TEXT N_("X coordinate")
  58 #define POSX_LONGTEXT N_("X coordinate of the mask.")
  59 #define POSY_TEXT N_("Y coordinate")
  60 #define POSY_LONGTEXT N_("Y coordinate of the mask.")
  61
  62 #define CFG_PREFIX "erase-"
  63
  64 vlc_module_begin ()
  65     set_description( N_("Erase video filter") )
  66     set_shortname( N_( "Erase" ))
  67     set_capability( "video filter2", 0 )
  68     set_category( CAT_VIDEO )
  69     set_subcategory( SUBCAT_VIDEO_VFILTER )
  70
  71     add_file( CFG_PREFIX "mask", NULL, NULL,
  72               MASK_TEXT, MASK_LONGTEXT, false )
  73     add_integer( CFG_PREFIX "x", 0, NULL, POSX_TEXT, POSX_LONGTEXT, false )
  74     add_integer( CFG_PREFIX "y", 0, NULL, POSY_TEXT, POSY_LONGTEXT, false )
  75
  76     add_shortcut( "erase" )
  77     set_callbacks( Create, Destroy )
  78 vlc_module_end ()
  79
  80 static const char *const ppsz_filter_options[] = {
  81     "mask", "x", "y", NULL
  82 };
  83
  84 /*****************************************************************************
  85  * filter_sys_t
  86  *****************************************************************************/
  87 struct filter_sys_t
  88 {
  89     int i_x;
  90     int i_y;
  91     picture_t *p_mask;
  92     vlc_mutex_t lock;
  93 };
  94
  95 static void LoadMask( filter_t *p_filter, const char *psz_filename )
  96 {
  97     image_handler_t *p_image;
  98     video_format_t fmt_in, fmt_out;
  99     picture_t *p_old_mask = p_filter->p_sys->p_mask;
 100     memset( &fmt_in, 0, sizeof( video_format_t ) );
 101     memset( &fmt_out, 0, sizeof( video_format_t ) );
 102     fmt_out.i_chroma = VLC_CODEC_YUVA;
 103     p_image = image_HandlerCreate( p_filter );
 104     p_filter->p_sys->p_mask =
 105         image_ReadUrl( p_image, psz_filename, &fmt_in, &fmt_out );
 106     if( p_filter->p_sys->p_mask )
 107     {
 108         if( p_old_mask )
 109             picture_Release( p_old_mask );
 110     }
 111     else if( p_old_mask )
 112     {
 113         p_filter->p_sys->p_mask = p_old_mask;
 114         msg_Err( p_filter, "Error while loading new mask. Keeping old mask." );
 115     }
 116     else
 117         msg_Err( p_filter, "Error while loading new mask. No mask available." );
 118
 119     image_HandlerDelete( p_image );
 120 }
 121
 122 /*****************************************************************************
 123  * Create
 124  *****************************************************************************/
 125 static int Create( vlc_object_t *p_this )
 126 {
 127     filter_t *p_filter = (filter_t *)p_this;
 128     filter_sys_t *p_sys;
 129     char *psz_filename;
 130
 131     switch( p_filter->fmt_in.video.i_chroma )
 132     {
 133         case VLC_CODEC_I420:
 134         case VLC_CODEC_J420:
 135         case VLC_CODEC_YV12:
 136
 137         case VLC_CODEC_I422:
 138         case VLC_CODEC_J422:
 139             break;
 140
 141         default:
 142             msg_Err( p_filter, "Unsupported input chroma (%4s)",
 143                      (char*)&(p_filter->fmt_in.video.i_chroma) );
 144             return VLC_EGENERIC;
 145     }
 146
 147     /* Allocate structure */
 148     p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
 149     if( p_filter->p_sys == NULL )
 150         return VLC_ENOMEM;
 151     p_sys = p_filter->p_sys;
 152
 153     p_filter->pf_video_filter = Filter;
 154
 155     config_ChainParse( p_filter, CFG_PREFIX, ppsz_filter_options,
 156                        p_filter->p_cfg );
 157
 158     psz_filename =
 159         var_CreateGetNonEmptyStringCommand( p_filter, CFG_PREFIX "mask" );
 160
 161     if( !psz_filename )
 162     {
 163         msg_Err( p_filter, "Missing 'mask' option value." );
 164         free( p_sys );
 165         return VLC_EGENERIC;
 166     }
 167
 168     p_sys->p_mask = NULL;
 169     LoadMask( p_filter, psz_filename );
 170     free( psz_filename );
 171
 172     p_sys->i_x = var_CreateGetIntegerCommand( p_filter, CFG_PREFIX "x" );
 173     p_sys->i_y = var_CreateGetIntegerCommand( p_filter, CFG_PREFIX "y" );
 174
 175     vlc_mutex_init( &p_sys->lock );
 176     var_AddCallback( p_filter, CFG_PREFIX "x", EraseCallback, p_sys );
 177     var_AddCallback( p_filter, CFG_PREFIX "y", EraseCallback, p_sys );
 178     var_AddCallback( p_filter, CFG_PREFIX "mask", EraseCallback, p_sys );
 179
 180     return VLC_SUCCESS;
 181 }
 182
 183 /*****************************************************************************
 184  * Destroy
 185  *****************************************************************************/
 186 static void Destroy( vlc_object_t *p_this )
 187 {
 188     filter_t *p_filter = (filter_t *)p_this;
 189     filter_sys_t *p_sys = p_filter->p_sys;
 190     if( p_sys->p_mask )
 191         picture_Release( p_sys->p_mask );
 192
 193     var_DelCallback( p_filter, CFG_PREFIX "x", EraseCallback, p_sys );
 194     var_DelCallback( p_filter, CFG_PREFIX "y", EraseCallback, p_sys );
 195     var_DelCallback( p_filter, CFG_PREFIX "mask", EraseCallback, p_sys );
 196     vlc_mutex_destroy( &p_sys->lock );
 197
 198     free( p_filter->p_sys );
 199 }
 200
 201 /*****************************************************************************
 202  * Filter
 203  *****************************************************************************/
 204 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 205 {
 206     picture_t *p_outpic;
 207     filter_sys_t *p_sys = p_filter->p_sys;
 208
 209     if( !p_pic ) return NULL;
 210
 211     p_outpic = filter_NewPicture( p_filter );
 212     if( !p_outpic )
 213     {
 214         picture_Release( p_pic );
 215         return NULL;
 216     }
 217
 218     /* If the mask is empty: just copy the image */
 219     vlc_mutex_lock( &p_sys->lock );
 220     if( p_sys->p_mask )
 221         FilterErase( p_filter, p_pic, p_outpic );
 222     else
 223         picture_CopyPixels( p_outpic, p_pic );
 224     vlc_mutex_unlock( &p_sys->lock );
 225
 226     return CopyInfoAndRelease( p_outpic, p_pic );
 227 }
 228
 229 /*****************************************************************************
 230  * FilterErase
 231  *****************************************************************************/
 232 static void FilterErase( filter_t *p_filter, picture_t *p_inpic,
 233                                              picture_t *p_outpic )
 234 {
 235     filter_sys_t *p_sys = p_filter->p_sys;
 236
 237     const int i_mask_pitch = p_sys->p_mask->A_PITCH;
 238     const int i_mask_visible_pitch = p_sys->p_mask->p[A_PLANE].i_visible_pitch;
 239     const int i_mask_visible_lines = p_sys->p_mask->p[A_PLANE].i_visible_lines;
 240
 241     for( int i_plane = 0; i_plane < p_inpic->i_planes; i_plane++ )
 242     {
 243         const int i_pitch = p_inpic->p[i_plane].i_pitch;
 244         const int i_2pitch = i_pitch<<1;
 245         const int i_visible_pitch = p_inpic->p[i_plane].i_visible_pitch;
 246         const int i_lines = p_inpic->p[i_plane].i_lines;
 247         const int i_visible_lines = p_inpic->p[i_plane].i_visible_lines;
 248
 249         uint8_t *p_inpix = p_inpic->p[i_plane].p_pixels;
 250         uint8_t *p_outpix = p_outpic->p[i_plane].p_pixels;
 251         uint8_t *p_mask = p_sys->p_mask->A_PIXELS;
 252         int i_x = p_sys->i_x, i_y = p_sys->i_y;
 253
 254         int x, y;
 255         int i_height = i_mask_visible_lines;
 256         int i_width  = i_mask_visible_pitch;
 257
 258         const bool b_line_factor = ( i_plane /* U_PLANE or V_PLANE */ &&
 259             !( p_inpic->format.i_chroma == VLC_CODEC_I422
 260             || p_inpic->format.i_chroma == VLC_CODEC_J422 ) );
 261
 262         if( i_plane ) /* U_PLANE or V_PLANE */
 263         {
 264             i_width  >>= 1;
 265             i_x      >>= 1;
 266         }
 267         if( b_line_factor )
 268         {
 269             i_height >>= 1;
 270             i_y      >>= 1;
 271         }
 272         i_height = __MIN( i_visible_lines - i_y, i_height );
 273         i_width  = __MIN( i_visible_pitch - i_x, i_width  );
 274
 275         /* Copy original pixel buffer */
 276         vlc_memcpy( p_outpix, p_inpix, i_pitch * i_lines );
 277
 278         /* Horizontal linear interpolation of masked areas */
 279         p_outpix = p_outpic->p[i_plane].p_pixels + i_y*i_pitch + i_x;
 280         for( y = 0; y < i_height;
 281              y++, p_mask += i_mask_pitch, p_outpix += i_pitch )
 282         {
 283             uint8_t prev, next = 0;
 284             int prev_x = -1, next_x = -2;
 285             int quot = 0;
 286
 287             /* Find a suitable value for the previous color to use when
 288              * interpoling a masked pixel's value */
 289             if( i_x )
 290             {
 291                 /* There are pixels before current position on the same line.
 292                  * Use those */
 293                 prev = *(p_outpix-1);
 294             }
 295             else if( y || i_y )
 296             {
 297                 /* This is the first pixel on a line but there other lines
 298                  * above us. Use the pixel right above */
 299                 prev = *(p_outpix-i_pitch);
 300             }
 301             else
 302             {
 303                 /* We're in the upper left corner. This sucks. We can't use
 304                  * any previous value, so we'll use a dummy one. In most
 305                  * cases this dummy value will be fixed later on in the
 306                  * algorithm */
 307                 prev = 0xff;
 308             }
 309
 310             for( x = 0; x < i_width; x++ )
 311             {
 312                 if( p_mask[i_plane?x<<1:x] > 127 )
 313                 {
 314                     /* This is a masked pixel */
 315                     if( next_x <= prev_x )
 316                     {
 317                         int x0;
 318                         /* Look for the next non masked pixel on the same
 319                          * line (inside the mask's bounding box) */
 320                         for( x0 = x; x0 < i_width; x0++ )
 321                         {
 322                             if( p_mask[i_plane?x0<<1:x0] <= 127 )
 323                             {
 324                                 /* We found an unmasked pixel. Victory! */
 325                                 next_x = x0;
 326                                 next = p_outpix[x0];
 327                                 break;
 328                             }
 329                         }
 330                         if( next_x <= prev_x )
 331                         {
 332                             /* We didn't find an unmasked pixel yet. Try
 333                              * harder */
 334                             if( x0 == x ) x0++;
 335                             if( x0 < i_visible_pitch )
 336                             {
 337                                 /* If we didn't find a non masked pixel on the
 338                                  * same line inside the mask's bounding box,
 339                                  * use the next pixel on the line (except if
 340                                  * it doesn't exist) */
 341                                 next_x = x0;
 342                                 next = p_outpix[x0];
 343                             }
 344                             else
 345                             {
 346                                 /* The last pixel on the line is masked,
 347                                  * so we'll use the "prev" value. A better
 348                                  * approach would be to use unmasked pixels
 349                                  * at the end of adjacent lines */
 350                                 next_x = x0;
 351                                 next = prev;
 352                             }
 353                         }
 354                         if( !( i_x || y || i_y ) )
 355                             /* We were unable to find a suitable value for
 356                              * the previous color (which means that we are
 357                              * on the first line in the upper left corner)
 358                              */
 359                             prev = next;
 360
 361                         /* Divide only once instead of next_x-prev_x-1 times */
 362                         quot = ((next-prev)<<16)/(next_x-prev_x);
 363                     }
 364                     /* Interpolate new value, and round correctly */
 365                     p_outpix[x] = prev + (((x-prev_x)*quot+(1<<16))>>16);
 366                 }
 367                 else
 368                 {
 369                     /* This pixel isn't masked. It's thus suitable as a
 370                      * previous color for the next interpolation */
 371                     prev = p_outpix[x];
 372                     prev_x = x;
 373                 }
 374             }
 375         }
 376
 377         /* Vertical bluring */
 378         p_mask = p_sys->p_mask->A_PIXELS;
 379         i_height = b_line_factor ? i_mask_visible_lines>>1
 380                                  : i_mask_visible_lines;
 381         /* Make sure that we stop at least 2 lines before the picture's end
 382          * (since our bluring algorithm uses the 2 next lines) */
 383         i_height = __MIN( i_visible_lines - i_y - 2, i_height );
 384         /* Make sure that we start at least 2 lines from the top (since our
 385          * bluring algorithm uses the 2 previous lines) */
 386         y = __MAX(i_y,2);
 387         p_outpix = p_outpic->p[i_plane].p_pixels + (i_y+y)*i_pitch + i_x;
 388         for( ; y < i_height; y++, p_mask += i_mask_pitch, p_outpix += i_pitch )
 389         {
 390             for( x = 0; x < i_width; x++ )
 391             {
 392                 if( p_mask[i_plane?x<<1:x] > 127 )
 393                 {
 394                     /* Ugly bluring function */
 395                     p_outpix[x] =
 396                         ( (p_outpix[x-i_2pitch]<<1)       /* 2 */
 397                         + (p_outpix[x-i_pitch ]<<2)       /* 4 */
 398                         + (p_outpix[x         ]<<2)       /* 4 */
 399                         + (p_outpix[x+i_pitch ]<<2)       /* 4 */
 400                         + (p_outpix[x+i_2pitch]<<1) )>>4; /* 2 */
 401                 }
 402             }
 403         }
 404     }
 405 }
 406
 407 static int EraseCallback( vlc_object_t *p_this, char const *psz_var,
 408                           vlc_value_t oldval, vlc_value_t newval, void *p_data )
 409 {
 410     VLC_UNUSED(oldval);
 411     filter_sys_t *p_sys = (filter_sys_t *)p_data;
 412
 413     if( !strcmp( psz_var, CFG_PREFIX "x" ) )
 414     {
 415         vlc_mutex_lock( &p_sys->lock );
 416         p_sys->i_x = newval.i_int;
 417         vlc_mutex_unlock( &p_sys->lock );
 418     }
 419     else if( !strcmp( psz_var, CFG_PREFIX "y" ) )
 420     {
 421         vlc_mutex_lock( &p_sys->lock );
 422         p_sys->i_y = newval.i_int;
 423         vlc_mutex_unlock( &p_sys->lock );
 424     }
 425     else if( !strcmp( psz_var, CFG_PREFIX "mask" ) )
 426     {
 427         vlc_mutex_lock( &p_sys->lock );
 428         LoadMask( (filter_t*)p_this, newval.psz_string );
 429         vlc_mutex_unlock( &p_sys->lock );
 430     }
 431     else
 432     {
 433         msg_Warn( p_this, "Unknown callback command." );
 434     }
 435     return VLC_SUCCESS;
 436 }