c883b25a9eb067897a5532d55cf85b29408a2760
[vlc.git] / 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     p_sys->i_x = var_CreateGetIntegerCommand( p_filter, CFG_PREFIX "x" );
172     p_sys->i_y = var_CreateGetIntegerCommand( p_filter, CFG_PREFIX "y" );
173
174     vlc_mutex_init( &p_sys->lock );
175     var_AddCallback( p_filter, CFG_PREFIX "x", EraseCallback, p_sys );
176     var_AddCallback( p_filter, CFG_PREFIX "y", EraseCallback, p_sys );
177     var_AddCallback( p_filter, CFG_PREFIX "mask", EraseCallback, p_sys );
178
179     return VLC_SUCCESS;
180 }
181
182 /*****************************************************************************
183  * Destroy
184  *****************************************************************************/
185 static void Destroy( vlc_object_t *p_this )
186 {
187     filter_t *p_filter = (filter_t *)p_this;
188     filter_sys_t *p_sys = p_filter->p_sys;
189     if( p_sys->p_mask )
190         picture_Release( p_sys->p_mask );
191
192     var_DelCallback( p_filter, CFG_PREFIX "x", EraseCallback, p_sys );
193     var_DelCallback( p_filter, CFG_PREFIX "y", EraseCallback, p_sys );
194     var_DelCallback( p_filter, CFG_PREFIX "mask", EraseCallback, p_sys );
195     vlc_mutex_destroy( &p_sys->lock );
196
197     free( p_filter->p_sys );
198 }
199
200 /*****************************************************************************
201  * Filter
202  *****************************************************************************/
203 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
204 {
205     picture_t *p_outpic;
206     filter_sys_t *p_sys = p_filter->p_sys;
207
208     if( !p_pic ) return NULL;
209
210     /* If the mask if empty return the picture */
211     vlc_mutex_lock( &p_sys->lock );
212     if( !p_sys->p_mask )
213     {
214         vlc_mutex_unlock( &p_sys->lock );
215         return p_pic;
216     }
217
218     p_outpic = filter_NewPicture( p_filter );
219     if( !p_outpic )
220     {
221         picture_Release( p_pic );
222         vlc_mutex_unlock( &p_sys->lock );
223         return NULL;
224     }
225
226     /* Here */
227     FilterErase( p_filter, p_pic, p_outpic );
228     vlc_mutex_unlock( &p_sys->lock );
229
230     return CopyInfoAndRelease( p_outpic, p_pic );
231 }
232
233 /*****************************************************************************
234  * FilterErase
235  *****************************************************************************/
236 static void FilterErase( filter_t *p_filter, picture_t *p_inpic,
237                                              picture_t *p_outpic )
238 {
239     filter_sys_t *p_sys = p_filter->p_sys;
240
241     const int i_mask_pitch = p_sys->p_mask->A_PITCH;
242     const int i_mask_visible_pitch = p_sys->p_mask->p[A_PLANE].i_visible_pitch;
243     const int i_mask_visible_lines = p_sys->p_mask->p[A_PLANE].i_visible_lines;
244
245     for( int i_plane = 0; i_plane < p_inpic->i_planes; i_plane++ )
246     {
247         const int i_pitch = p_inpic->p[i_plane].i_pitch;
248         const int i_2pitch = i_pitch<<1;
249         const int i_visible_pitch = p_inpic->p[i_plane].i_visible_pitch;
250         const int i_lines = p_inpic->p[i_plane].i_lines;
251         const int i_visible_lines = p_inpic->p[i_plane].i_visible_lines;
252
253         uint8_t *p_inpix = p_inpic->p[i_plane].p_pixels;
254         uint8_t *p_outpix = p_outpic->p[i_plane].p_pixels;
255         uint8_t *p_mask = p_sys->p_mask->A_PIXELS;
256         int i_x = p_sys->i_x, i_y = p_sys->i_y;
257
258         int x, y;
259         int i_height = i_mask_visible_lines;
260         int i_width  = i_mask_visible_pitch;
261
262         const bool b_line_factor = ( i_plane /* U_PLANE or V_PLANE */ &&
263             !( p_inpic->format.i_chroma == VLC_CODEC_I422
264             || p_inpic->format.i_chroma == VLC_CODEC_J422 ) );
265
266         if( i_plane ) /* U_PLANE or V_PLANE */
267         {
268             i_width  >>= 1;
269             i_x      >>= 1;
270         }
271         if( b_line_factor )
272         {
273             i_height >>= 1;
274             i_y      >>= 1;
275         }
276         i_height = __MIN( i_visible_lines - i_y, i_height );
277         i_width  = __MIN( i_visible_pitch - i_x, i_width  );
278
279         /* Copy original pixel buffer */
280         vlc_memcpy( p_outpix, p_inpix, i_pitch * i_lines );
281
282         /* Horizontal linear interpolation of masked areas */
283         p_outpix = p_outpic->p[i_plane].p_pixels + i_y*i_pitch + i_x;
284         for( y = 0; y < i_height;
285              y++, p_mask += i_mask_pitch, p_outpix += i_pitch )
286         {
287             uint8_t prev, next = 0;
288             int prev_x = -1, next_x = -2;
289             int quot = 0;
290
291             /* Find a suitable value for the previous color to use when
292              * interpoling a masked pixel's value */
293             if( i_x )
294             {
295                 /* There are pixels before current position on the same line.
296                  * Use those */
297                 prev = *(p_outpix-1);
298             }
299             else if( y || i_y )
300             {
301                 /* This is the first pixel on a line but there other lines
302                  * above us. Use the pixel right above */
303                 prev = *(p_outpix-i_pitch);
304             }
305             else
306             {
307                 /* We're in the upper left corner. This sucks. We can't use
308                  * any previous value, so we'll use a dummy one. In most
309                  * cases this dummy value will be fixed later on in the
310                  * algorithm */
311                 prev = 0xff;
312             }
313
314             for( x = 0; x < i_width; x++ )
315             {
316                 if( p_mask[i_plane?x<<1:x] > 127 )
317                 {
318                     /* This is a masked pixel */
319                     if( next_x <= prev_x )
320                     {
321                         int x0;
322                         /* Look for the next non masked pixel on the same
323                          * line (inside the mask's bounding box) */
324                         for( x0 = x; x0 < i_width; x0++ )
325                         {
326                             if( p_mask[i_plane?x0<<1:x0] <= 127 )
327                             {
328                                 /* We found an unmasked pixel. Victory! */
329                                 next_x = x0;
330                                 next = p_outpix[x0];
331                                 break;
332                             }
333                         }
334                         if( next_x <= prev_x )
335                         {
336                             /* We didn't find an unmasked pixel yet. Try
337                              * harder */
338                             if( x0 == x ) x0++;
339                             if( x0 < i_visible_pitch )
340                             {
341                                 /* If we didn't find a non masked pixel on the
342                                  * same line inside the mask's bounding box,
343                                  * use the next pixel on the line (except if
344                                  * it doesn't exist) */
345                                 next_x = x0;
346                                 next = p_outpix[x0];
347                             }
348                             else
349                             {
350                                 /* The last pixel on the line is masked,
351                                  * so we'll use the "prev" value. A better
352                                  * approach would be to use unmasked pixels
353                                  * at the end of adjacent lines */
354                                 next_x = x0;
355                                 next = prev;
356                             }
357                         }
358                         if( !( i_x || y || i_y ) )
359                             /* We were unable to find a suitable value for
360                              * the previous color (which means that we are
361                              * on the first line in the upper left corner)
362                              */
363                             prev = next;
364
365                         /* Divide only once instead of next_x-prev_x-1 times */
366                         quot = ((next-prev)<<16)/(next_x-prev_x);
367                     }
368                     /* Interpolate new value, and round correctly */
369                     p_outpix[x] = prev + (((x-prev_x)*quot+(1<<16))>>16);
370                 }
371                 else
372                 {
373                     /* This pixel isn't masked. It's thus suitable as a
374                      * previous color for the next interpolation */
375                     prev = p_outpix[x];
376                     prev_x = x;
377                 }
378             }
379         }
380
381         /* Vertical bluring */
382         p_mask = p_sys->p_mask->A_PIXELS;
383         i_height = b_line_factor ? i_mask_visible_lines>>1
384                                  : i_mask_visible_lines;
385         /* Make sure that we stop at least 2 lines before the picture's end
386          * (since our bluring algorithm uses the 2 next lines) */
387         i_height = __MIN( i_visible_lines - i_y - 2, i_height );
388         /* Make sure that we start at least 2 lines from the top (since our
389          * bluring algorithm uses the 2 previous lines) */
390         y = __MAX(i_y,2);
391         p_outpix = p_outpic->p[i_plane].p_pixels + (i_y+y)*i_pitch + i_x;
392         for( ; y < i_height; y++, p_mask += i_mask_pitch, p_outpix += i_pitch )
393         {
394             for( x = 0; x < i_width; x++ )
395             {
396                 if( p_mask[i_plane?x<<1:x] > 127 )
397                 {
398                     /* Ugly bluring function */
399                     p_outpix[x] =
400                         ( (p_outpix[x-i_2pitch]<<1)       /* 2 */
401                         + (p_outpix[x-i_pitch ]<<2)       /* 4 */
402                         + (p_outpix[x         ]<<2)       /* 4 */
403                         + (p_outpix[x+i_pitch ]<<2)       /* 4 */
404                         + (p_outpix[x+i_2pitch]<<1) )>>4; /* 2 */
405                 }
406             }
407         }
408     }
409 }
410
411 static int EraseCallback( vlc_object_t *p_this, char const *psz_var,
412                           vlc_value_t oldval, vlc_value_t newval, void *p_data )
413 {
414     VLC_UNUSED(oldval);
415     filter_sys_t *p_sys = (filter_sys_t *)p_data;
416
417     if( !strcmp( psz_var, CFG_PREFIX "x" ) )
418     {
419         vlc_mutex_lock( &p_sys->lock );
420         p_sys->i_x = newval.i_int;
421         vlc_mutex_unlock( &p_sys->lock );
422     }
423     else if( !strcmp( psz_var, CFG_PREFIX "y" ) )
424     {
425         vlc_mutex_lock( &p_sys->lock );
426         p_sys->i_y = newval.i_int;
427         vlc_mutex_unlock( &p_sys->lock );
428     }
429     else if( !strcmp( psz_var, CFG_PREFIX "mask" ) )
430     {
431         vlc_mutex_lock( &p_sys->lock );
432         LoadMask( (filter_t*)p_this, newval.psz_string );
433         vlc_mutex_unlock( &p_sys->lock );
434     }
435     else
436     {
437         msg_Warn( p_this, "Unknown callback command." );
438     }
439     return VLC_SUCCESS;
440 }