Fix i_pitch vs i_visible_pitch bug.
[vlc.git] / modules / video_filter / noise.c
1 /*****************************************************************************
2  * noise.c : "add noise to image" video filter
3  *****************************************************************************
4  * Copyright (C) 2000-2006 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 #include <stdlib.h>                                      /* malloc(), free() */
28 #include <string.h>
29
30 #include <vlc/vlc.h>
31 #include <vlc_vout.h>
32
33 #include "vlc_filter.h"
34
35 /*****************************************************************************
36  * Local prototypes
37  *****************************************************************************/
38 static int  Create    ( vlc_object_t * );
39 static void Destroy   ( vlc_object_t * );
40
41 static picture_t *Filter( filter_t *, picture_t * );
42
43 #define FILTER_PREFIX "noise-"
44
45 /*****************************************************************************
46  * Module descriptor
47  *****************************************************************************/
48 vlc_module_begin();
49     set_description( _("Noise video filter") );
50     set_shortname( _( "Noise" ));
51     set_capability( "video filter2", 0 );
52     set_category( CAT_VIDEO );
53     set_subcategory( SUBCAT_VIDEO_VFILTER );
54
55     add_shortcut( "noise" );
56     set_callbacks( Create, Destroy );
57 vlc_module_end();
58
59 static const char *ppsz_filter_options[] = {
60     NULL
61 };
62
63 /*****************************************************************************
64  * vout_sys_t: Distort video output method descriptor
65  *****************************************************************************
66  * This structure is part of the video output thread descriptor.
67  * It describes the Distort specific properties of an output thread.
68  *****************************************************************************/
69 struct filter_sys_t
70 {
71     mtime_t last_date;
72 };
73
74 /*****************************************************************************
75  * Create: allocates Distort video thread output method
76  *****************************************************************************
77  * This function allocates and initializes a Distort vout method.
78  *****************************************************************************/
79 static int Create( vlc_object_t *p_this )
80 {
81     filter_t *p_filter = (filter_t *)p_this;
82
83     /* Allocate structure */
84     p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
85     if( p_filter->p_sys == NULL )
86     {
87         msg_Err( p_filter, "out of memory" );
88         return VLC_ENOMEM;
89     }
90
91     config_ChainParse( p_filter, FILTER_PREFIX, ppsz_filter_options,
92                        p_filter->p_cfg );
93
94     p_filter->pf_video_filter = Filter;
95
96     p_filter->p_sys->last_date = 0;
97
98     return VLC_SUCCESS;
99 }
100
101 /*****************************************************************************
102  * Destroy: destroy Distort video thread output method
103  *****************************************************************************
104  * Terminate an output method created by DistortCreateOutputMethod
105  *****************************************************************************/
106 static void Destroy( vlc_object_t *p_this )
107 {
108     filter_t *p_filter = (filter_t *)p_this;
109     free( p_filter->p_sys );
110 }
111
112 /*****************************************************************************
113  * Render: displays previously rendered output
114  *****************************************************************************
115  * This function send the currently rendered image to Distort image, waits
116  * until it is displayed and switch the two rendering buffers, preparing next
117  * frame.
118  *****************************************************************************/
119 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
120 {
121     picture_t *p_outpic;
122     filter_sys_t *p_sys = p_filter->p_sys;
123     int i_index;
124     mtime_t new_date = mdate();
125
126     if( !p_pic ) return NULL;
127
128     p_outpic = p_filter->pf_vout_buffer_new( p_filter );
129     if( !p_outpic )
130     {
131         msg_Warn( p_filter, "can't get output picture" );
132         if( p_pic->pf_release )
133             p_pic->pf_release( p_pic );
134         return NULL;
135     }
136
137     p_sys->last_date = new_date;
138
139     for( i_index = 0 ; i_index < p_pic->i_planes ; i_index++ )
140     {
141         uint8_t *p_in = p_pic->p[i_index].p_pixels;
142         uint8_t *p_out = p_outpic->p[i_index].p_pixels;
143
144         const int i_num_lines = p_pic->p[i_index].i_visible_lines;
145         const int i_num_cols = p_pic->p[i_index].i_visible_pitch;
146         const int i_pitch = p_pic->p[i_index].i_pitch;
147
148         int i_line, i_col;
149
150         for( i_line = 0 ; i_line < i_num_lines ; i_line++ )
151         {
152             if( rand()%8 )
153             {
154                 /* line isn't noisy */
155                 p_filter->p_libvlc->pf_memcpy( p_out+i_line*i_pitch,
156                                                p_in+i_line*i_pitch,
157                                                i_num_cols );
158             }
159             else
160             {
161                 /* this line is noisy */
162                 int noise_level = rand()%8+2;
163                 for( i_col = 0; i_col < i_num_cols ; i_col++ )
164                 {
165                     if( rand()%noise_level )
166                     {
167                         p_out[i_line*i_pitch+i_col] =
168                             p_in[i_line*i_pitch+i_col];
169                     }
170                     else
171                     {
172                         p_out[i_line*i_pitch+i_col] = (rand()%3)*0x7f;
173                     }
174                 }
175             }
176         }
177     }
178
179     p_outpic->date = p_pic->date;
180     p_outpic->b_force = p_pic->b_force;
181     p_outpic->i_nb_fields = p_pic->i_nb_fields;
182     p_outpic->b_progressive = p_pic->b_progressive;
183     p_outpic->b_top_field_first = p_pic->b_top_field_first;
184
185     if( p_pic->pf_release )
186         p_pic->pf_release( p_pic );
187
188     return p_outpic;
189 }