Remove most stray semi-colons in module descriptions
[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_common.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. Uses 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( N_("Alpha mask video filter") )
64     set_shortname( N_("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 *const 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         return VLC_ENOMEM;
106     p_sys = p_filter->p_sys;
107
108     config_ChainParse( p_filter, CFG_PREFIX, ppsz_filter_options,
109                        p_filter->p_cfg );
110
111     vlc_mutex_init( &p_sys->mask_lock );
112     psz_string =
113         var_CreateGetStringCommand( p_filter, CFG_PREFIX "mask" );
114     var_AddCallback( p_filter, CFG_PREFIX "mask", MaskCallback,
115                      p_filter );
116     p_sys->p_mask = NULL;
117     if( psz_string && *psz_string )
118     {
119         LoadMask( p_filter, psz_string );
120         if( !p_sys->p_mask )
121             msg_Err( p_filter, "Error while loading mask (%s).",
122                      psz_string );
123     }
124     free( psz_string );
125
126     p_filter->pf_video_filter = Filter;
127
128     return VLC_SUCCESS;
129 }
130
131 static void Destroy( vlc_object_t *p_this )
132 {
133     filter_t *p_filter = (filter_t *)p_this;
134     filter_sys_t *p_sys = p_filter->p_sys;
135
136     vlc_mutex_destroy( &p_sys->mask_lock );
137     if( p_filter->p_sys->p_mask )
138         picture_Release( p_filter->p_sys->p_mask );
139
140     free( p_filter->p_sys );
141 }
142
143 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
144 {
145     filter_sys_t *p_sys = p_filter->p_sys;
146
147     vlc_mutex_lock( &p_sys->mask_lock );
148     plane_t *p_mask = p_sys->p_mask->p+A_PLANE;
149     plane_t *p_apic = p_pic->p+A_PLANE;
150     if(    p_mask->i_visible_pitch
151         != p_apic->i_visible_pitch
152         || p_mask->i_visible_lines
153         != p_apic->i_visible_lines )
154     {
155         msg_Err( p_filter,
156                   "Mask size (%d x %d) and image size (%d x %d) "
157                   "don't match. The mask will not be applied.",
158                   p_mask->i_visible_pitch,
159                   p_mask->i_visible_lines,
160                   p_apic->i_visible_pitch,
161                   p_apic->i_visible_lines );
162     }
163     else
164     {
165         plane_CopyPixels( p_apic, p_mask );
166     }
167     vlc_mutex_unlock( &p_sys->mask_lock );
168     return p_pic;
169 }
170
171 /* copied from video_filters/erase.c . Gruik ? */
172 static void LoadMask( filter_t *p_filter, const char *psz_filename )
173 {
174     image_handler_t *p_image;
175     video_format_t fmt_in, fmt_out;
176     memset( &fmt_in, 0, sizeof( video_format_t ) );
177     memset( &fmt_out, 0, sizeof( video_format_t ) );
178     fmt_out.i_chroma = VLC_FOURCC('Y','U','V','A');
179     if( p_filter->p_sys->p_mask )
180         picture_Release( p_filter->p_sys->p_mask );
181     p_image = image_HandlerCreate( p_filter );
182     p_filter->p_sys->p_mask =
183         image_ReadUrl( p_image, psz_filename, &fmt_in, &fmt_out );
184     image_HandlerDelete( p_image );
185 }
186
187 /*****************************************************************************
188 * Callback to update params on the fly
189 *****************************************************************************/
190 static int MaskCallback( vlc_object_t *p_this, char const *psz_var,
191                          vlc_value_t oldval, vlc_value_t newval,
192                          void *p_data )
193 {
194     VLC_UNUSED(p_this); VLC_UNUSED(oldval);
195     filter_t *p_filter = (filter_t *)p_data;
196     filter_sys_t *p_sys = p_filter->p_sys;
197     int i_ret = VLC_SUCCESS;
198
199 #define VAR_IS( a ) !strcmp( psz_var, CFG_PREFIX a )
200     if( VAR_IS( "mask" ) )
201     {
202         vlc_mutex_lock( &p_sys->mask_lock );
203         if( newval.psz_string && *newval.psz_string )
204         {
205             LoadMask( p_filter, newval.psz_string );
206             if( !p_sys->p_mask )
207             {
208                 msg_Err( p_filter, "Error while loading mask (%s).",
209                          newval.psz_string );
210                 i_ret = VLC_EGENERIC;
211             }
212         }
213         else if( p_sys->p_mask )
214         {
215             picture_Release( p_sys->p_mask );
216             p_sys->p_mask = NULL;
217         }
218         vlc_mutex_unlock( &p_sys->mask_lock );
219     }
220 #undef VAR_IS
221
222     return i_ret;
223 }