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 ERASE_HELP N_("Remove zones of the video using a picture as mask")
  63
  64 #define CFG_PREFIX "erase-"
  65
  66 vlc_module_begin ()
  67     set_description( N_("Erase video filter") )
  68     set_shortname( N_( "Erase" ))
  69     set_capability( "video filter2", 0 )
  70     set_help(ERASE_HELP)
  71     set_category( CAT_VIDEO )
  72     set_subcategory( SUBCAT_VIDEO_VFILTER )
  73
  74     add_file( CFG_PREFIX "mask", NULL, NULL,
  75               MASK_TEXT, MASK_LONGTEXT, false )
  76     add_integer( CFG_PREFIX "x", 0, NULL, POSX_TEXT, POSX_LONGTEXT, false )
  77     add_integer( CFG_PREFIX "y", 0, NULL, POSY_TEXT, POSY_LONGTEXT, false )
  78
  79     add_shortcut( "erase" )
  80     set_callbacks( Create, Destroy )
  81 vlc_module_end ()
  82
  83 static const char *const ppsz_filter_options[] = {
  84     "mask", "x", "y", NULL
  85 };
  86
  87 /*****************************************************************************
  88  * filter_sys_t
  89  *****************************************************************************/
  90 struct filter_sys_t
  91 {
  92     int i_x;
  93     int i_y;
  94     picture_t *p_mask;
  95     vlc_mutex_t lock;
  96 };
  97
  98 static void LoadMask( filter_t *p_filter, const char *psz_filename )
  99 {
 100     image_handler_t *p_image;
 101     video_format_t fmt_in, fmt_out;
 102     picture_t *p_old_mask = p_filter->p_sys->p_mask;
 103     memset( &fmt_in, 0, sizeof( video_format_t ) );
 104     memset( &fmt_out, 0, sizeof( video_format_t ) );
 105     fmt_out.i_chroma = VLC_CODEC_YUVA;
 106     p_image = image_HandlerCreate( p_filter );
 107     p_filter->p_sys->p_mask =
 108         image_ReadUrl( p_image, psz_filename, &fmt_in, &fmt_out );
 109     if( p_filter->p_sys->p_mask )
 110     {
 111         if( p_old_mask )
 112             picture_Release( p_old_mask );
 113     }
 114     else if( p_old_mask )
 115     {
 116         p_filter->p_sys->p_mask = p_old_mask;
 117         msg_Err( p_filter, "Error while loading new mask. Keeping old mask." );
 118     }
 119     else
 120         msg_Err( p_filter, "Error while loading new mask. No mask available." );
 121
 122     image_HandlerDelete( p_image );
 123 }
 124
 125 /*****************************************************************************
 126  * Create
 127  *****************************************************************************/
 128 static int Create( vlc_object_t *p_this )
 129 {
 130     filter_t *p_filter = (filter_t *)p_this;
 131     filter_sys_t *p_sys;
 132     char *psz_filename;
 133
 134     switch( p_filter->fmt_in.video.i_chroma )
 135     {
 136         case VLC_CODEC_I420:
 137         case VLC_CODEC_J420:
 138         case VLC_CODEC_YV12:
 139
 140         case VLC_CODEC_I422:
 141         case VLC_CODEC_J422:
 142             break;
 143
 144         default:
 145             msg_Err( p_filter, "Unsupported input chroma (%4s)",
 146                      (char*)&(p_filter->fmt_in.video.i_chroma) );
 147             return VLC_EGENERIC;
 148     }
 149
 150     /* Allocate structure */
 151     p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
 152     if( p_filter->p_sys == NULL )
 153         return VLC_ENOMEM;
 154     p_sys = p_filter->p_sys;
 155
 156     p_filter->pf_video_filter = Filter;
 157
 158     config_ChainParse( p_filter, CFG_PREFIX, ppsz_filter_options,
 159                        p_filter->p_cfg );
 160
 161     psz_filename =
 162         var_CreateGetNonEmptyStringCommand( p_filter, CFG_PREFIX "mask" );
 163
 164     if( !psz_filename )
 165     {
 166         msg_Err( p_filter, "Missing 'mask' option value." );
 167         free( p_sys );
 168         return VLC_EGENERIC;
 169     }
 170
 171     p_sys->p_mask = NULL;
 172     LoadMask( p_filter, psz_filename );
 173     free( psz_filename );
 174
 175     p_sys->i_x = var_CreateGetIntegerCommand( p_filter, CFG_PREFIX "x" );
 176     p_sys->i_y = var_CreateGetIntegerCommand( p_filter, CFG_PREFIX "y" );
 177
 178     vlc_mutex_init( &p_sys->lock );
 179     var_AddCallback( p_filter, CFG_PREFIX "x", EraseCallback, p_sys );
 180     var_AddCallback( p_filter, CFG_PREFIX "y", EraseCallback, p_sys );
 181     var_AddCallback( p_filter, CFG_PREFIX "mask", EraseCallback, p_sys );
 182
 183     return VLC_SUCCESS;
 184 }
 185
 186 /*****************************************************************************
 187  * Destroy
 188  *****************************************************************************/
 189 static void Destroy( vlc_object_t *p_this )
 190 {
 191     filter_t *p_filter = (filter_t *)p_this;
 192     filter_sys_t *p_sys = p_filter->p_sys;
 193     if( p_sys->p_mask )
 194         picture_Release( p_sys->p_mask );
 195
 196     var_DelCallback( p_filter, CFG_PREFIX "x", EraseCallback, p_sys );
 197     var_DelCallback( p_filter, CFG_PREFIX "y", EraseCallback, p_sys );
 198     var_DelCallback( p_filter, CFG_PREFIX "mask", EraseCallback, p_sys );
 199     vlc_mutex_destroy( &p_sys->lock );
 200
 201     free( p_filter->p_sys );
 202 }
 203
 204 /*****************************************************************************
 205  * Filter
 206  *****************************************************************************/
 207 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 208 {
 209     picture_t *p_outpic;
 210     filter_sys_t *p_sys = p_filter->p_sys;
 211
 212     if( !p_pic ) return NULL;
 213
 214     p_outpic = filter_NewPicture( p_filter );
 215     if( !p_outpic )
 216     {
 217         picture_Release( p_pic );
 218         return NULL;
 219     }
 220
 221     /* If the mask is empty: just copy the image */
 222     vlc_mutex_lock( &p_sys->lock );
 223     if( p_sys->p_mask )
 224         FilterErase( p_filter, p_pic, p_outpic );
 225     else
 226         picture_CopyPixels( p_outpic, p_pic );
 227     vlc_mutex_unlock( &p_sys->lock );
 228
 229     return CopyInfoAndRelease( p_outpic, p_pic );
 230 }
 231
 232 /*****************************************************************************
 233  * FilterErase
 234  *****************************************************************************/
 235 static void FilterErase( filter_t *p_filter, picture_t *p_inpic,
 236                                              picture_t *p_outpic )
 237 {
 238     filter_sys_t *p_sys = p_filter->p_sys;
 239
 240     const int i_mask_pitch = p_sys->p_mask->A_PITCH;
 241     const int i_mask_visible_pitch = p_sys->p_mask->p[A_PLANE].i_visible_pitch;
 242     const int i_mask_visible_lines = p_sys->p_mask->p[A_PLANE].i_visible_lines;
 243
 244     for( int i_plane = 0; i_plane < p_inpic->i_planes; i_plane++ )
 245     {
 246         const int i_pitch = p_inpic->p[i_plane].i_pitch;
 247         const int i_2pitch = i_pitch<<1;
 248         const int i_visible_pitch = p_inpic->p[i_plane].i_visible_pitch;
 249         const int i_lines = p_inpic->p[i_plane].i_lines;
 250         const int i_visible_lines = p_inpic->p[i_plane].i_visible_lines;
 251
 252         uint8_t *p_inpix = p_inpic->p[i_plane].p_pixels;
 253         uint8_t *p_outpix = p_outpic->p[i_plane].p_pixels;
 254         uint8_t *p_mask = p_sys->p_mask->A_PIXELS;
 255         int i_x = p_sys->i_x, i_y = p_sys->i_y;
 256
 257         int x, y;
 258         int i_height = i_mask_visible_lines;
 259         int i_width  = i_mask_visible_pitch;
 260
 261         const bool b_line_factor = ( i_plane /* U_PLANE or V_PLANE */ &&
 262             !( p_inpic->format.i_chroma == VLC_CODEC_I422
 263             || p_inpic->format.i_chroma == VLC_CODEC_J422 ) );
 264
 265         if( i_plane ) /* U_PLANE or V_PLANE */
 266         {
 267             i_width  >>= 1;
 268             i_x      >>= 1;
 269         }
 270         if( b_line_factor )
 271         {
 272             i_height >>= 1;
 273             i_y      >>= 1;
 274         }
 275         i_height = __MIN( i_visible_lines - i_y, i_height );
 276         i_width  = __MIN( i_visible_pitch - i_x, i_width  );
 277
 278         /* Copy original pixel buffer */
 279         vlc_memcpy( p_outpix, p_inpix, i_pitch * i_lines );
 280
 281         /* Horizontal linear interpolation of masked areas */
 282         p_outpix = p_outpic->p[i_plane].p_pixels + i_y*i_pitch + i_x;
 283         for( y = 0; y < i_height;
 284              y++, p_mask += i_mask_pitch, p_outpix += i_pitch )
 285         {
 286             uint8_t prev, next = 0;
 287             int prev_x = -1, next_x = -2;
 288             int quot = 0;
 289
 290             /* Find a suitable value for the previous color to use when
 291              * interpoling a masked pixel's value */
 292             if( i_x )
 293             {
 294                 /* There are pixels before current position on the same line.
 295                  * Use those */
 296                 prev = *(p_outpix-1);
 297             }
 298             else if( y || i_y )
 299             {
 300                 /* This is the first pixel on a line but there other lines
 301                  * above us. Use the pixel right above */
 302                 prev = *(p_outpix-i_pitch);
 303             }
 304             else
 305             {
 306                 /* We're in the upper left corner. This sucks. We can't use
 307                  * any previous value, so we'll use a dummy one. In most
 308                  * cases this dummy value will be fixed later on in the
 309                  * algorithm */
 310                 prev = 0xff;
 311             }
 312
 313             for( x = 0; x < i_width; x++ )
 314             {
 315                 if( p_mask[i_plane?x<<1:x] > 127 )
 316                 {
 317                     /* This is a masked pixel */
 318                     if( next_x <= prev_x )
 319                     {
 320                         int x0;
 321                         /* Look for the next non masked pixel on the same
 322                          * line (inside the mask's bounding box) */
 323                         for( x0 = x; x0 < i_width; x0++ )
 324                         {
 325                             if( p_mask[i_plane?x0<<1:x0] <= 127 )
 326                             {
 327                                 /* We found an unmasked pixel. Victory! */
 328                                 next_x = x0;
 329                                 next = p_outpix[x0];
 330                                 break;
 331                             }
 332                         }
 333                         if( next_x <= prev_x )
 334                         {
 335                             /* We didn't find an unmasked pixel yet. Try
 336                              * harder */
 337                             if( x0 == x ) x0++;
 338                             if( x0 < i_visible_pitch )
 339                             {
 340                                 /* If we didn't find a non masked pixel on the
 341                                  * same line inside the mask's bounding box,
 342                                  * use the next pixel on the line (except if
 343                                  * it doesn't exist) */
 344                                 next_x = x0;
 345                                 next = p_outpix[x0];
 346                             }
 347                             else
 348                             {
 349                                 /* The last pixel on the line is masked,
 350                                  * so we'll use the "prev" value. A better
 351                                  * approach would be to use unmasked pixels
 352                                  * at the end of adjacent lines */
 353                                 next_x = x0;
 354                                 next = prev;
 355                             }
 356                         }
 357                         if( !( i_x || y || i_y ) )
 358                             /* We were unable to find a suitable value for
 359                              * the previous color (which means that we are
 360                              * on the first line in the upper left corner)
 361                              */
 362                             prev = next;
 363
 364                         /* Divide only once instead of next_x-prev_x-1 times */
 365                         quot = ((next-prev)<<16)/(next_x-prev_x);
 366                     }
 367                     /* Interpolate new value, and round correctly */
 368                     p_outpix[x] = prev + (((x-prev_x)*quot+(1<<16))>>16);
 369                 }
 370                 else
 371                 {
 372                     /* This pixel isn't masked. It's thus suitable as a
 373                      * previous color for the next interpolation */
 374                     prev = p_outpix[x];
 375                     prev_x = x;
 376                 }
 377             }
 378         }
 379
 380         /* Vertical bluring */
 381         p_mask = p_sys->p_mask->A_PIXELS;
 382         i_height = b_line_factor ? i_mask_visible_lines>>1
 383                                  : i_mask_visible_lines;
 384         /* Make sure that we stop at least 2 lines before the picture's end
 385          * (since our bluring algorithm uses the 2 next lines) */
 386         i_height = __MIN( i_visible_lines - i_y - 2, i_height );
 387         /* Make sure that we start at least 2 lines from the top (since our
 388          * bluring algorithm uses the 2 previous lines) */
 389         y = __MAX(i_y,2);
 390         p_outpix = p_outpic->p[i_plane].p_pixels + (i_y+y)*i_pitch + i_x;
 391         for( ; y < i_height; y++, p_mask += i_mask_pitch, p_outpix += i_pitch )
 392         {
 393             for( x = 0; x < i_width; x++ )
 394             {
 395                 if( p_mask[i_plane?x<<1:x] > 127 )
 396                 {
 397                     /* Ugly bluring function */
 398                     p_outpix[x] =
 399                         ( (p_outpix[x-i_2pitch]<<1)       /* 2 */
 400                         + (p_outpix[x-i_pitch ]<<2)       /* 4 */
 401                         + (p_outpix[x         ]<<2)       /* 4 */
 402                         + (p_outpix[x+i_pitch ]<<2)       /* 4 */
 403                         + (p_outpix[x+i_2pitch]<<1) )>>4; /* 2 */
 404                 }
 405             }
 406         }
 407     }
 408 }
 409
 410 static int EraseCallback( vlc_object_t *p_this, char const *psz_var,
 411                           vlc_value_t oldval, vlc_value_t newval, void *p_data )
 412 {
 413     VLC_UNUSED(oldval);
 414     filter_sys_t *p_sys = (filter_sys_t *)p_data;
 415
 416     if( !strcmp( psz_var, CFG_PREFIX "x" ) )
 417     {
 418         vlc_mutex_lock( &p_sys->lock );
 419         p_sys->i_x = newval.i_int;
 420         vlc_mutex_unlock( &p_sys->lock );
 421     }
 422     else if( !strcmp( psz_var, CFG_PREFIX "y" ) )
 423     {
 424         vlc_mutex_lock( &p_sys->lock );
 425         p_sys->i_y = newval.i_int;
 426         vlc_mutex_unlock( &p_sys->lock );
 427     }
 428     else if( !strcmp( psz_var, CFG_PREFIX "mask" ) )
 429     {
 430         vlc_mutex_lock( &p_sys->lock );
 431         LoadMask( (filter_t*)p_this, newval.psz_string );
 432         vlc_mutex_unlock( &p_sys->lock );
 433     }
 434     else
 435     {
 436         msg_Warn( p_this, "Unknown callback command." );
 437     }
 438     return VLC_SUCCESS;
 439 }