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>
35 #include <vlc_filter.h>
36 #include "filter_picture.h"
38 #include <math.h> /* exp(), sqrt() */
40 /*****************************************************************************
42 *****************************************************************************/
43 static int Create ( vlc_object_t * );
44 static void Destroy ( vlc_object_t * );
46 #define SIGMA_TEXT N_("Gaussian's std deviation")
47 #define SIGMA_LONGTEXT N_( \
48 "Gaussian's standard deviation. The bluring will take " \
49 "into account pixels up to 3*sigma away in any direction.")
51 #define FILTER_PREFIX "gaussianblur-"
54 set_description( N_("Gaussian blur video filter") )
55 set_shortname( N_( "Gaussian Blur" ))
56 set_capability( "video filter2", 0 )
57 set_category( CAT_VIDEO )
58 set_subcategory( SUBCAT_VIDEO_VFILTER )
60 add_float( FILTER_PREFIX "sigma", 2., NULL, SIGMA_TEXT, SIGMA_LONGTEXT,
63 set_callbacks( Create, Destroy )
66 /*****************************************************************************
68 *****************************************************************************/
69 static picture_t *Filter( filter_t *, picture_t * );
71 static const char *const ppsz_filter_options[] = {
75 /* Comment this to use floats instead of integers (faster for bigger sigma
77 * For sigma = 2 ints are faster
78 * For sigma = 4 floats are faster
80 #define DONT_USE_FLOATS
82 #ifdef DONT_USE_FLOATS
93 type_t *pt_distribution;
98 static void gaussianblur_InitDistribution( filter_sys_t *p_sys )
100 double f_sigma = p_sys->f_sigma;
101 int i_dim = (int)(3.*f_sigma);
102 type_t *pt_distribution = malloc( (2*i_dim+1) * sizeof( type_t ) );
105 for( x = -i_dim; x <= i_dim; x++ )
107 const float f_distribution = sqrt( exp(-(x*x)/(f_sigma*f_sigma) ) / (2.*M_PI*f_sigma*f_sigma) );
108 #ifdef DONT_USE_FLOATS
109 const float f_factor = 1 << 8;
111 const float f_factor = 1;
114 pt_distribution[i_dim+x] = (type_t)( f_distribution * f_factor );
115 //printf("%f\n",(float)pt_distribution[i_dim+x]);
117 p_sys->i_dim = i_dim;
118 p_sys->pt_distribution = pt_distribution;
121 static int Create( vlc_object_t *p_this )
123 filter_t *p_filter = (filter_t *)p_this;
125 if( p_filter->fmt_in.video.i_chroma != VLC_CODEC_I420
126 && p_filter->fmt_in.video.i_chroma != VLC_CODEC_J420
127 && p_filter->fmt_in.video.i_chroma != VLC_CODEC_YV12
129 && p_filter->fmt_in.video.i_chroma != VLC_CODEC_I422
130 && p_filter->fmt_in.video.i_chroma != VLC_CODEC_J422
133 /* We only want planar YUV 4:2:0 or 4:2:2 */
134 msg_Err( p_filter, "Unsupported input chroma (%4s)",
135 (char*)&(p_filter->fmt_in.video.i_chroma) );
139 if( p_filter->fmt_in.video.i_chroma != p_filter->fmt_out.video.i_chroma )
141 msg_Err( p_filter, "Input and output chromas don't match" );
145 p_filter->p_sys = malloc( sizeof( filter_sys_t ) );
146 if( p_filter->p_sys == NULL )
149 config_ChainParse( p_filter, FILTER_PREFIX, ppsz_filter_options,
152 p_filter->pf_video_filter = Filter;
154 p_filter->p_sys->f_sigma =
155 var_CreateGetFloat( p_filter, FILTER_PREFIX "sigma" );
156 if( p_filter->p_sys->f_sigma <= 0. )
158 msg_Err( p_filter, "sigma must be positive" );
161 gaussianblur_InitDistribution( p_filter->p_sys );
162 msg_Dbg( p_filter, "gaussian distribution is %d pixels wide",
163 p_filter->p_sys->i_dim*2+1 );
165 p_filter->p_sys->pt_buffer = NULL;
166 p_filter->p_sys->pt_scale = NULL;
171 static void Destroy( vlc_object_t *p_this )
173 filter_t *p_filter = (filter_t *)p_this;
175 free( p_filter->p_sys->pt_distribution );
176 free( p_filter->p_sys->pt_buffer );
177 free( p_filter->p_sys->pt_scale );
179 free( p_filter->p_sys );
182 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
185 filter_sys_t *p_sys = p_filter->p_sys;
187 const int i_dim = p_sys->i_dim;
190 const type_t *pt_distribution = p_sys->pt_distribution;
192 if( !p_pic ) return NULL;
194 p_outpic = filter_NewPicture( p_filter );
197 picture_Release( p_pic );
200 if( !p_sys->pt_buffer )
202 p_sys->pt_buffer = realloc( p_sys->pt_buffer,
203 p_pic->p[Y_PLANE].i_visible_lines *
204 p_pic->p[Y_PLANE].i_pitch *
208 pt_buffer = p_sys->pt_buffer;
209 if( !p_sys->pt_scale )
211 const int i_visible_lines = p_pic->p[Y_PLANE].i_visible_lines;
212 const int i_visible_pitch = p_pic->p[Y_PLANE].i_visible_pitch;
213 const int i_pitch = p_pic->p[Y_PLANE].i_pitch;
216 p_sys->pt_scale = malloc( i_visible_lines * i_pitch * sizeof( type_t ) );
217 pt_scale = p_sys->pt_scale;
219 for( i_line = 0 ; i_line < i_visible_lines ; i_line++ )
221 for( i_col = 0; i_col < i_visible_pitch ; i_col++ )
226 for( y = __MAX( -i_dim, -i_line );
227 y <= __MIN( i_dim, i_visible_lines - i_line - 1 );
230 for( x = __MAX( -i_dim, -i_col );
231 x <= __MIN( i_dim, i_visible_pitch - i_col + 1 );
234 t_value += pt_distribution[y+i_dim] *
235 pt_distribution[x+i_dim];
238 pt_scale[i_line*i_pitch+i_col] = t_value;
243 pt_scale = p_sys->pt_scale;
244 for( i_plane = 0 ; i_plane < p_pic->i_planes ; i_plane++ )
247 uint8_t *p_in = p_pic->p[i_plane].p_pixels;
248 uint8_t *p_out = p_outpic->p[i_plane].p_pixels;
250 const int i_visible_lines = p_pic->p[i_plane].i_visible_lines;
251 const int i_visible_pitch = p_pic->p[i_plane].i_visible_pitch;
252 const int i_pitch = p_pic->p[i_plane].i_pitch;
255 const int x_factor = p_pic->p[Y_PLANE].i_visible_pitch/i_visible_pitch-1;
256 const int y_factor = p_pic->p[Y_PLANE].i_visible_lines/i_visible_lines-1;
258 for( i_line = 0 ; i_line < i_visible_lines ; i_line++ )
260 for( i_col = 0; i_col < i_visible_pitch ; i_col++ )
264 const int c = i_line*i_pitch+i_col;
265 for( x = __MAX( -i_dim, -i_col*(x_factor+1) );
266 x <= __MIN( i_dim, (i_visible_pitch - i_col)*(x_factor+1) + 1 );
269 t_value += pt_distribution[x+i_dim] *
270 p_in[c+(x>>x_factor)];
272 pt_buffer[c] = t_value;
275 for( i_line = 0 ; i_line < i_visible_lines ; i_line++ )
277 for( i_col = 0; i_col < i_visible_pitch ; i_col++ )
281 const int c = i_line*i_pitch+i_col;
282 for( y = __MAX( -i_dim, (-i_line)*(y_factor+1) );
283 y <= __MIN( i_dim, (i_visible_lines - i_line)*(y_factor+1) - 1 );
286 t_value += pt_distribution[y+i_dim] *
287 pt_buffer[c+(y>>y_factor)*i_pitch];
290 const type_t t_scale = pt_scale[(i_line<<y_factor)*(i_pitch<<x_factor)+(i_col<<x_factor)];
291 p_out[c] = (uint8_t)(t_value / t_scale); // FIXME wouldn't it be better to round instead of trunc ?
296 return CopyInfoAndRelease( p_outpic, p_pic );