Include vlc_plugin.h as needed
[vlc.git] / modules / video_filter / alphamask.c
1 /*****************************************************************************
2  * alphamask.c : Alpha layer mask video filter for vlc
3  *****************************************************************************
4  * Copyright (C) 2007 the VideoLAN team
5  * $Id$
6  *
7  * Authors: Antoine Cellerier <dionoea at videolan tod 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/vlc.h>
33 #include <vlc_plugin.h>
34 #include <vlc_vout.h>
35
36 #include <vlc_image.h>
37 #include <vlc_filter.h>
38
39 #define ALPHAMASK_HELP N_( \
40     "Use an image's alpha channel as a transparency mask." )
41
42 #define MASK_TEXT N_("Transparency mask")
43 #define MASK_LONGTEXT N_( \
44     "Alpha blending transparency mask. Use's a png alpha channel.")
45
46 #define CFG_PREFIX "alphamask-"
47
48 /*****************************************************************************
49  * Local prototypes
50  *****************************************************************************/
51 static int  Create      ( vlc_object_t * );
52 static void Destroy     ( vlc_object_t * );
53
54 static picture_t *Filter( filter_t *, picture_t * );
55 static void LoadMask( filter_t *, const char * );
56 static int MaskCallback( vlc_object_t *, char const *,
57                          vlc_value_t, vlc_value_t, void * );
58
59 /*****************************************************************************
60  * Module descriptor
61  *****************************************************************************/
62 vlc_module_begin();
63     set_description( _("Alpha mask video filter") );
64     set_shortname( _("Alpha mask" ));
65     set_help( ALPHAMASK_HELP );
66     set_category( CAT_VIDEO );
67     set_subcategory( SUBCAT_VIDEO_VFILTER );
68     set_capability( "video filter2", 0 );
69     add_shortcut( "alphamask" );
70     add_shortcut( "mask" );
71     set_callbacks( Create, Destroy );
72
73     add_string( CFG_PREFIX "mask", NULL, NULL, MASK_TEXT,
74                 MASK_LONGTEXT, false );
75 vlc_module_end();
76
77 static const char *ppsz_filter_options[] = {
78     "mask", NULL
79 };
80
81 struct filter_sys_t
82 {
83     picture_t *p_mask;
84     vlc_mutex_t mask_lock;
85 };
86
87 static int Create( vlc_object_t *p_this )
88 {
89     filter_t *p_filter = (filter_t *)p_this;
90     filter_sys_t *p_sys;
91     char *psz_string;
92
93     if( p_filter->fmt_in.video.i_chroma != VLC_FOURCC('Y','U','V','A') )
94     {
95         msg_Err( p_filter,
96                  "Unsupported input chroma \"%4s\". "
97                  "Alphamask can only use \"YUVA\".",
98                  (char*)&p_filter->fmt_in.video.i_chroma );
99         return VLC_EGENERIC;
100     }
101
102     /* Allocate structure */
103     p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
104     if( p_filter->p_sys == NULL )
105     {
106         msg_Err( p_filter, "out of memory" );
107         return VLC_ENOMEM;
108     }
109     p_sys = p_filter->p_sys;
110
111     config_ChainParse( p_filter, CFG_PREFIX, ppsz_filter_options,
112                        p_filter->p_cfg );
113
114     vlc_mutex_init( &p_sys->mask_lock );
115     psz_string =
116         var_CreateGetStringCommand( p_filter, CFG_PREFIX "mask" );
117     var_AddCallback( p_filter, CFG_PREFIX "mask", MaskCallback,
118                      p_filter );
119     p_sys->p_mask = NULL;
120     if( psz_string && *psz_string )
121     {
122         LoadMask( p_filter, psz_string );
123         if( !p_sys->p_mask )
124             msg_Err( p_filter, "Error while loading mask (%s).",
125                      psz_string );
126     }
127     free( psz_string );
128
129     p_filter->pf_video_filter = Filter;
130
131     return VLC_SUCCESS;
132 }
133
134 static void Destroy( vlc_object_t *p_this )
135 {
136     filter_t *p_filter = (filter_t *)p_this;
137     filter_sys_t *p_sys = p_filter->p_sys;
138
139     vlc_mutex_destroy( &p_sys->mask_lock );
140     if( p_filter->p_sys->p_mask )
141         p_filter->p_sys->p_mask->pf_release( p_filter->p_sys->p_mask );
142
143     free( p_filter->p_sys );
144 }
145
146 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
147 {
148     filter_sys_t *p_sys = p_filter->p_sys;
149
150     vlc_mutex_lock( &p_sys->mask_lock );
151     plane_t *p_mask = p_sys->p_mask->p+A_PLANE;
152     plane_t *p_apic = p_pic->p+A_PLANE;
153     if(    p_mask->i_visible_pitch
154         != p_apic->i_visible_pitch
155         || p_mask->i_visible_lines
156         != p_apic->i_visible_lines )
157     {
158         msg_Warn( p_filter,
159                   "Mask size (%d x %d) and image size (%d x %d) "
160                   "don't match. The mask will not be applied.",
161                   p_mask->i_visible_pitch,
162                   p_mask->i_visible_lines,
163                   p_apic->i_visible_pitch,
164                   p_apic->i_visible_lines );
165     }
166     else
167     {
168         if( p_mask->i_pitch != p_apic->i_pitch
169         ||  p_mask->i_lines != p_apic->i_lines )
170         {
171             /* visible plane sizes match ... but not the underlying
172              * buffer. I'm not sure that this can happen,
173              * but better safe than sorry. */
174             int i_line;
175             int i_lines = p_mask->i_visible_lines;
176             uint8_t *p_src = p_mask->p_pixels;
177             uint8_t *p_dst = p_apic->p_pixels;
178             int i_src_pitch = p_mask->i_pitch;
179             int i_dst_pitch = p_apic->i_pitch;
180             int i_visible_pitch = p_mask->i_visible_pitch;
181             for( i_line = 0; i_line < i_lines; i_line++,
182                  p_src += i_src_pitch, p_dst += i_dst_pitch )
183             {
184                 vlc_memcpy( p_dst, p_src, i_visible_pitch );
185             }
186         }
187         else
188         {
189             /* plane sizes match */
190             vlc_memcpy( p_apic->p_pixels, p_mask->p_pixels,
191                         p_mask->i_pitch * p_mask->i_lines );
192         }
193     }
194     vlc_mutex_unlock( &p_sys->mask_lock );
195     return p_pic;
196 }
197
198 /* copied from video_filters/erase.c . Gruik ? */
199 static void LoadMask( filter_t *p_filter, const char *psz_filename )
200 {
201     image_handler_t *p_image;
202     video_format_t fmt_in, fmt_out;
203     memset( &fmt_in, 0, sizeof( video_format_t ) );
204     memset( &fmt_out, 0, sizeof( video_format_t ) );
205     fmt_out.i_chroma = VLC_FOURCC('Y','U','V','A');
206     if( p_filter->p_sys->p_mask )
207         p_filter->p_sys->p_mask->pf_release( p_filter->p_sys->p_mask );
208     p_image = image_HandlerCreate( p_filter );
209     p_filter->p_sys->p_mask =
210         image_ReadUrl( p_image, psz_filename, &fmt_in, &fmt_out );
211     image_HandlerDelete( p_image );
212 }
213
214 /*****************************************************************************
215 * Callback to update params on the fly
216 *****************************************************************************/
217 static int MaskCallback( vlc_object_t *p_this, char const *psz_var,
218                          vlc_value_t oldval, vlc_value_t newval,
219                          void *p_data )
220 {
221     VLC_UNUSED(p_this); VLC_UNUSED(oldval);
222     filter_t *p_filter = (filter_t *)p_data;
223     filter_sys_t *p_sys = p_filter->p_sys;
224     int i_ret = VLC_SUCCESS;
225
226 #define VAR_IS( a ) !strcmp( psz_var, CFG_PREFIX a )
227     if( VAR_IS( "mask" ) )
228     {
229         vlc_mutex_lock( &p_sys->mask_lock );
230         if( newval.psz_string && *newval.psz_string )
231         {
232             LoadMask( p_filter, newval.psz_string );
233             if( !p_sys->p_mask )
234             {
235                 msg_Err( p_filter, "Error while loading mask (%s).",
236                          newval.psz_string );
237                 i_ret = VLC_EGENERIC;
238             }
239         }
240         else if( p_sys->p_mask )
241         {
242             p_sys->p_mask->pf_release( p_sys->p_mask );
243             p_sys->p_mask = NULL;
244         }
245         vlc_mutex_unlock( &p_sys->mask_lock );
246     }
247 #undef VAR_IS
248
249     return i_ret;
250 }