Remove unnedeeded msg_Error.
[vlc.git] / modules / video_filter / opencv_example.cpp
1 /*****************************************************************************
2  * opencv_example.cpp : Example OpenCV internal video filter
3  * (performs face identification).  Mostly taken from the facedetect.c
4  * OpenCV sample.
5  *****************************************************************************
6  * Copyright (C) 2006 the VideoLAN team
7  *
8  * Authors: Dugal Harris <dugalh@protoclea.co.za>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
23  *****************************************************************************/
24
25 /*****************************************************************************
26  * Preamble
27  *****************************************************************************/
28 #include <cxcore.h>
29 #include <cv.h>
30 #include <highgui.h>
31
32
33 #ifdef HAVE_CONFIG_H
34 # include "config.h"
35 #endif
36
37 #include <vlc_common.h>
38 #include <vlc_plugin.h>
39 #include <vlc_filter.h>
40 #include "filter_common.h"
41 #include <vlc_image.h>
42 #include "filter_event_info.h"
43
44 /*****************************************************************************
45  * filter_sys_t : filter descriptor
46  *****************************************************************************/
47 struct filter_sys_t
48 {
49     CvMemStorage* p_storage;
50     CvHaarClassifierCascade* p_cascade;
51     video_filter_event_info_t event_info;
52     int i_id;
53 };
54
55 /****************************************************************************
56  * Local prototypes
57  ****************************************************************************/
58 static int  OpenFilter ( vlc_object_t * );
59 static void CloseFilter( vlc_object_t * );
60
61 static picture_t *Filter( filter_t *, picture_t * );
62
63 /*****************************************************************************
64  * Module descriptor
65  *****************************************************************************/
66 vlc_module_begin();
67     set_description( N_("OpenCV face detection example filter") );
68     set_shortname( N_( "OpenCV example" ));
69     set_capability( "opencv example", 1 );
70     add_shortcut( "opencv_example" );
71
72     set_category( CAT_VIDEO );
73     set_subcategory( SUBCAT_VIDEO_VFILTER2 );
74     set_callbacks( OpenFilter, CloseFilter );
75
76     add_string( "opencv-haarcascade-file", "c:\\haarcascade_frontalface_alt.xml", NULL,
77                           N_("Haar cascade filename"),
78                           N_("Name of XML file containing Haar cascade description"), false);
79 vlc_module_end();
80
81 /*****************************************************************************
82  * OpenFilter: probe the filter and return score
83  *****************************************************************************/
84 static int OpenFilter( vlc_object_t *p_this )
85 {
86     filter_t *p_filter = (filter_t*)p_this;
87     filter_sys_t *p_sys;
88
89     /* Allocate the memory needed to store the decoder's structure */
90     if( ( p_filter->p_sys = p_sys =
91           (filter_sys_t *)malloc(sizeof(filter_sys_t)) ) == NULL )
92     {
93         return VLC_ENOMEM;
94     }
95
96     //init the video_filter_event_info_t struct
97     p_sys->event_info.i_region_size = 0;
98     p_sys->event_info.p_region = NULL;
99     p_sys->i_id = 0;
100
101     p_filter->pf_video_filter = Filter;
102
103     //create the VIDEO_FILTER_EVENT_VARIABLE
104     vlc_value_t val;
105     if (var_Create( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE, VLC_VAR_ADDRESS | VLC_VAR_DOINHERIT ) != VLC_SUCCESS)
106         msg_Err( p_filter, "Could not create %s\n", VIDEO_FILTER_EVENT_VARIABLE);
107
108     val.p_address = &(p_sys->event_info);
109     if (var_Set( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE, val )!=VLC_SUCCESS)
110         msg_Err( p_filter, "Could not set %s\n", VIDEO_FILTER_EVENT_VARIABLE);
111
112     //OpenCV init specific to this example
113     char* filename = config_GetPsz( p_filter, "opencv-haarcascade-file" );
114     p_filter->p_sys->p_cascade = (CvHaarClassifierCascade*)cvLoad( filename, 0, 0, 0 );
115     p_filter->p_sys->p_storage = cvCreateMemStorage(0);
116
117     return VLC_SUCCESS;
118 }
119
120 /*****************************************************************************
121  * CloseFilter: clean up the filter
122  *****************************************************************************/
123 static void CloseFilter( vlc_object_t *p_this )
124 {
125     filter_t *p_filter = (filter_t*)p_this;
126     filter_sys_t *p_sys = p_filter->p_sys;
127
128     if( p_filter->p_sys->p_cascade )
129         cvReleaseHaarClassifierCascade( &p_filter->p_sys->p_cascade );
130
131     if( p_filter->p_sys->p_storage )
132         cvReleaseMemStorage( &p_filter->p_sys->p_storage );
133
134     if (NULL != p_filter->p_sys->event_info.p_region)
135         free(p_filter->p_sys->event_info.p_region);
136
137     free( p_sys );
138
139     var_Destroy( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE);
140 }
141
142 /****************************************************************************
143  * Filter: Check for faces and raises an event when one is found.
144  ****************************************************************************
145  * p_pic: A picture_t with its p_data_orig member set to an array of
146  * IplImages (one image for each picture_t plane).
147  ****************************************************************************/
148 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
149 {
150     IplImage** p_img = NULL;
151     int i_planes = 0;
152     CvPoint pt1, pt2;
153     int i, scale = 1;
154  
155     if ((!p_pic) )
156     {
157         msg_Err( p_filter, "no image array" );
158         return NULL;
159     }
160     if (!(p_pic->p_data_orig))
161     {
162         msg_Err( p_filter, "no image array" );
163         return NULL;
164     }
165     //(hack) cast the picture_t to array of IplImage*
166     p_img = (IplImage**) p_pic->p_data_orig;
167     i_planes = p_pic->i_planes;
168
169     //check the image array for validity
170     if ((!p_img[0]))    //1st plane is 'I' i.e. greyscale
171     {
172         msg_Err( p_filter, "no image" );
173         return NULL;
174     }
175     if ((p_pic->format.i_chroma != VLC_FOURCC('I','4','2','0')))
176     {
177         msg_Err( p_filter, "wrong chroma - use I420" );
178         return NULL;
179     }
180     if (i_planes<1)
181     {
182         msg_Err( p_filter, "no image planes" );
183         return NULL;
184     }
185
186     //perform face detection
187     cvClearMemStorage(p_filter->p_sys->p_storage);
188     CvSeq* faces = NULL;
189     if( p_filter->p_sys->p_cascade )
190     {
191         //we should make some of these params config variables
192         faces = cvHaarDetectObjects( p_img[0], p_filter->p_sys->p_cascade,
193             p_filter->p_sys->p_storage, 1.15, 5, CV_HAAR_DO_CANNY_PRUNING,
194                                             cvSize(20, 20) );
195         //create the video_filter_region_info_t struct
196         CvRect* r;
197         if (faces && (faces->total > 0))
198         {
199             //msg_Dbg( p_filter, "Found %d face(s)\n", faces->total );
200             if (NULL != p_filter->p_sys->event_info.p_region)
201             {
202                 free(p_filter->p_sys->event_info.p_region);
203                 p_filter->p_sys->event_info.p_region = NULL;
204             }
205             if( NULL == ( p_filter->p_sys->event_info.p_region =
206                   (video_filter_region_info_t *)malloc(faces->total*sizeof(video_filter_region_info_t))))
207             {
208                 return NULL;
209             }
210             memset(p_filter->p_sys->event_info.p_region, 0, faces->total*sizeof(video_filter_region_info_t));
211             p_filter->p_sys->event_info.i_region_size = faces->total;
212         }
213
214         //populate the video_filter_region_info_t struct
215         for( i = 0; i < (faces ? faces->total : 0); i++ )
216         {
217             r = (CvRect*)cvGetSeqElem( faces, i );
218             pt1.x = r->x*scale;
219             pt2.x = (r->x+r->width)*scale;
220             pt1.y = r->y*scale;
221             pt2.y = (r->y+r->height)*scale;
222             cvRectangle( p_img[0], pt1, pt2, CV_RGB(0,0,0), 3, 8, 0 );
223
224             *(CvRect*)(&(p_filter->p_sys->event_info.p_region[i])) = *r;
225             p_filter->p_sys->event_info.p_region[i].i_id = p_filter->p_sys->i_id++;
226             p_filter->p_sys->event_info.p_region[i].p_description = "Face Detected";
227         }
228
229         if (faces && (faces->total > 0))    //raise the video filter event
230             var_Change( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE, VLC_VAR_TRIGGER_CALLBACKS, NULL, NULL );
231     }
232     else
233         msg_Err( p_filter, "No cascade - is opencv-haarcascade-file valid?" );
234
235     return p_pic;
236 }
237