1 /*****************************************************************************
2 * gaussianblur.c : gaussian blur video filter
3 *****************************************************************************
4 * Copyright (C) 2000-2007 the VideoLAN team
7 * Authors: Antoine Cellerier <dionoea -at- videolan -dot- org>
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.
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.
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 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
32 #include <vlc_common.h>
33 #include <vlc_plugin.h>
36 #include "vlc_filter.h"
37 #include "filter_picture.h"
39 #include <math.h> /* exp(), sqrt() */
41 /*****************************************************************************
43 *****************************************************************************/
44 static int Create ( vlc_object_t * );
45 static void Destroy ( vlc_object_t * );
47 #define SIGMA_TEXT N_("Gaussian's std deviation")
48 #define SIGMA_LONGTEXT N_( \
49 "Gaussian's standard deviation. The bluring will take " \
50 "into account pixels up to 3*sigma away in any direction.")
52 #define FILTER_PREFIX "gaussianblur-"
55 set_description( N_("Gaussian blur video filter") )
56 set_shortname( N_( "Gaussian Blur" ))
57 set_capability( "video filter2", 0 )
58 set_category( CAT_VIDEO )
59 set_subcategory( SUBCAT_VIDEO_VFILTER )
61 add_float( FILTER_PREFIX "sigma", 2., NULL, SIGMA_TEXT, SIGMA_LONGTEXT,
64 set_callbacks( Create, Destroy )
67 /*****************************************************************************
69 *****************************************************************************/
70 static picture_t *Filter( filter_t *, picture_t * );
72 static const char *const ppsz_filter_options[] = {
76 /* Comment this to use floats instead of integers (faster for bigger sigma
78 * For sigma = 2 ints are faster
79 * For sigma = 4 floats are faster
81 #define DONT_USE_FLOATS
83 #ifdef DONT_USE_FLOATS
94 type_t *pt_distribution;
99 static void gaussianblur_InitDistribution( filter_sys_t *p_sys )
101 double f_sigma = p_sys->f_sigma;
102 int i_dim = (int)(3.*f_sigma);
103 type_t *pt_distribution = malloc( (2*i_dim+1) * sizeof( type_t ) );
106 for( x = -i_dim; x <= i_dim; x++ )
108 const float f_distribution = sqrt( exp(-(x*x)/(f_sigma*f_sigma) ) / (2.*M_PI*f_sigma*f_sigma) );
109 #ifdef DONT_USE_FLOATS
110 const float f_factor = 1 << 8;
112 const float f_factor = 1;
115 pt_distribution[i_dim+x] = (type_t)( f_distribution * f_factor );
116 //printf("%f\n",(float)pt_distribution[i_dim+x]);
118 p_sys->i_dim = i_dim;
119 p_sys->pt_distribution = pt_distribution;
122 static int Create( vlc_object_t *p_this )
124 filter_t *p_filter = (filter_t *)p_this;
126 if( p_filter->fmt_in.video.i_chroma != VLC_FOURCC('I','4','2','0')
127 && p_filter->fmt_in.video.i_chroma != VLC_FOURCC('I','Y','U','V')
128 && p_filter->fmt_in.video.i_chroma != VLC_FOURCC('J','4','2','0')
129 && p_filter->fmt_in.video.i_chroma != VLC_FOURCC('Y','V','1','2')
131 && p_filter->fmt_in.video.i_chroma != VLC_FOURCC('I','4','2','2')
132 && p_filter->fmt_in.video.i_chroma != VLC_FOURCC('J','4','2','2')
135 /* We only want planar YUV 4:2:0 or 4:2:2 */
136 msg_Err( p_filter, "Unsupported input chroma (%4s)",
137 (char*)&(p_filter->fmt_in.video.i_chroma) );
141 if( p_filter->fmt_in.video.i_chroma != p_filter->fmt_out.video.i_chroma )
143 msg_Err( p_filter, "Input and output chromas don't match" );
147 p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
148 if( p_filter->p_sys == NULL )
151 config_ChainParse( p_filter, FILTER_PREFIX, ppsz_filter_options,
154 p_filter->pf_video_filter = Filter;
156 p_filter->p_sys->f_sigma =
157 var_CreateGetFloat( p_filter, FILTER_PREFIX "sigma" );
158 if( p_filter->p_sys->f_sigma <= 0. )
160 msg_Err( p_filter, "sigma must be positive" );
163 gaussianblur_InitDistribution( p_filter->p_sys );
164 msg_Dbg( p_filter, "gaussian distribution is %d pixels wide",
165 p_filter->p_sys->i_dim*2+1 );
167 p_filter->p_sys->pt_buffer = NULL;
168 p_filter->p_sys->pt_scale = NULL;
173 static void Destroy( vlc_object_t *p_this )
175 filter_t *p_filter = (filter_t *)p_this;
177 free( p_filter->p_sys->pt_distribution );
178 free( p_filter->p_sys->pt_buffer );
179 free( p_filter->p_sys->pt_scale );
181 free( p_filter->p_sys );
184 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
187 filter_sys_t *p_sys = p_filter->p_sys;
189 const int i_dim = p_sys->i_dim;
192 const type_t *pt_distribution = p_sys->pt_distribution;
194 if( !p_pic ) return NULL;
196 p_outpic = filter_NewPicture( p_filter );
199 picture_Release( p_pic );
202 if( !p_sys->pt_buffer )
204 p_sys->pt_buffer = realloc( p_sys->pt_buffer,
205 p_pic->p[Y_PLANE].i_visible_lines *
206 p_pic->p[Y_PLANE].i_pitch *
210 pt_buffer = p_sys->pt_buffer;
211 if( !p_sys->pt_scale )
213 const int i_visible_lines = p_pic->p[Y_PLANE].i_visible_lines;
214 const int i_visible_pitch = p_pic->p[Y_PLANE].i_visible_pitch;
215 const int i_pitch = p_pic->p[Y_PLANE].i_pitch;
218 p_sys->pt_scale = malloc( i_visible_lines * i_pitch * sizeof( type_t ) );
219 pt_scale = p_sys->pt_scale;
221 for( i_line = 0 ; i_line < i_visible_lines ; i_line++ )
223 for( i_col = 0; i_col < i_visible_pitch ; i_col++ )
228 for( y = __MAX( -i_dim, -i_line );
229 y <= __MIN( i_dim, i_visible_lines - i_line - 1 );
232 for( x = __MAX( -i_dim, -i_col );
233 x <= __MIN( i_dim, i_visible_pitch - i_col + 1 );
236 t_value += pt_distribution[y+i_dim] *
237 pt_distribution[x+i_dim];
240 pt_scale[i_line*i_pitch+i_col] = t_value;
245 pt_scale = p_sys->pt_scale;
246 for( i_plane = 0 ; i_plane < p_pic->i_planes ; i_plane++ )
249 uint8_t *p_in = p_pic->p[i_plane].p_pixels;
250 uint8_t *p_out = p_outpic->p[i_plane].p_pixels;
252 const int i_visible_lines = p_pic->p[i_plane].i_visible_lines;
253 const int i_visible_pitch = p_pic->p[i_plane].i_visible_pitch;
254 const int i_pitch = p_pic->p[i_plane].i_pitch;
257 const int x_factor = p_pic->p[Y_PLANE].i_visible_pitch/i_visible_pitch-1;
258 const int y_factor = p_pic->p[Y_PLANE].i_visible_lines/i_visible_lines-1;
260 for( i_line = 0 ; i_line < i_visible_lines ; i_line++ )
262 for( i_col = 0; i_col < i_visible_pitch ; i_col++ )
266 const int c = i_line*i_pitch+i_col;
267 for( x = __MAX( -i_dim, -i_col*(x_factor+1) );
268 x <= __MIN( i_dim, (i_visible_pitch - i_col)*(x_factor+1) + 1 );
271 t_value += pt_distribution[x+i_dim] *
272 p_in[c+(x>>x_factor)];
274 pt_buffer[c] = t_value;
277 for( i_line = 0 ; i_line < i_visible_lines ; i_line++ )
279 for( i_col = 0; i_col < i_visible_pitch ; i_col++ )
283 const int c = i_line*i_pitch+i_col;
284 for( y = __MAX( -i_dim, (-i_line)*(y_factor+1) );
285 y <= __MIN( i_dim, (i_visible_lines - i_line)*(y_factor+1) - 1 );
288 t_value += pt_distribution[y+i_dim] *
289 pt_buffer[c+(y>>y_factor)*i_pitch];
292 const type_t t_scale = pt_scale[(i_line<<y_factor)*(i_pitch<<x_factor)+(i_col<<x_factor)];
293 p_out[c] = (uint8_t)(t_value / t_scale); // FIXME wouldn't it be better to round instead of trunc ?
298 return CopyInfoAndRelease( p_outpic, p_pic );