git.sesse.net Git - vlc/blob - 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 <vlc_vout.h>
  41 #include "filter_common.h"
  42 #include <vlc_image.h>
  43 #include "filter_event_info.h"
  44
  45 /*****************************************************************************
  46  * filter_sys_t : filter descriptor
  47  *****************************************************************************/
  48 struct filter_sys_t
  49 {
  50     CvMemStorage* p_storage;
  51     CvHaarClassifierCascade* p_cascade;
  52     video_filter_event_info_t event_info;
  53     int i_id;
  54 };
  55
  56 /****************************************************************************
  57  * Local prototypes
  58  ****************************************************************************/
  59 static int  OpenFilter ( vlc_object_t * );
  60 static void CloseFilter( vlc_object_t * );
  61
  62 static picture_t *Filter( filter_t *, picture_t * );
  63
  64 /*****************************************************************************
  65  * Module descriptor
  66  *****************************************************************************/
  67 vlc_module_begin ()
  68     set_description( N_("OpenCV face detection example filter") )
  69     set_shortname( N_( "OpenCV example" ))
  70     set_capability( "opencv example", 1 )
  71     add_shortcut( "opencv_example" )
  72
  73     set_category( CAT_VIDEO )
  74     set_subcategory( SUBCAT_VIDEO_VFILTER2 )
  75     set_callbacks( OpenFilter, CloseFilter )
  76
  77     add_string( "opencv-haarcascade-file", "c:\\haarcascade_frontalface_alt.xml", NULL,
  78                           N_("Haar cascade filename"),
  79                           N_("Name of XML file containing Haar cascade description"), false);
  80 vlc_module_end ()
  81
  82 /*****************************************************************************
  83  * OpenFilter: probe the filter and return score
  84  *****************************************************************************/
  85 static int OpenFilter( vlc_object_t *p_this )
  86 {
  87     filter_t *p_filter = (filter_t*)p_this;
  88     filter_sys_t *p_sys;
  89
  90     /* Allocate the memory needed to store the decoder's structure */
  91     if( ( p_filter->p_sys = p_sys =
  92           (filter_sys_t *)malloc(sizeof(filter_sys_t)) ) == NULL )
  93     {
  94         return VLC_ENOMEM;
  95     }
  96
  97     //init the video_filter_event_info_t struct
  98     p_sys->event_info.i_region_size = 0;
  99     p_sys->event_info.p_region = NULL;
 100     p_sys->i_id = 0;
 101
 102     p_filter->pf_video_filter = Filter;
 103
 104     //create the VIDEO_FILTER_EVENT_VARIABLE
 105     vlc_value_t val;
 106     if (var_Create( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE, VLC_VAR_ADDRESS | VLC_VAR_DOINHERIT ) != VLC_SUCCESS)
 107         msg_Err( p_filter, "Could not create %s", VIDEO_FILTER_EVENT_VARIABLE);
 108
 109     val.p_address = &(p_sys->event_info);
 110     if (var_Set( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE, val )!=VLC_SUCCESS)
 111         msg_Err( p_filter, "Could not set %s", VIDEO_FILTER_EVENT_VARIABLE);
 112
 113     //OpenCV init specific to this example
 114     char* filename = config_GetPsz( p_filter, "opencv-haarcascade-file" );
 115     p_filter->p_sys->p_cascade = (CvHaarClassifierCascade*)cvLoad( filename, 0, 0, 0 );
 116     p_filter->p_sys->p_storage = cvCreateMemStorage(0);
 117     free( filename );
 118
 119     return VLC_SUCCESS;
 120 }
 121
 122 /*****************************************************************************
 123  * CloseFilter: clean up the filter
 124  *****************************************************************************/
 125 static void CloseFilter( vlc_object_t *p_this )
 126 {
 127     filter_t *p_filter = (filter_t*)p_this;
 128     filter_sys_t *p_sys = p_filter->p_sys;
 129
 130     if( p_filter->p_sys->p_cascade )
 131         cvReleaseHaarClassifierCascade( &p_filter->p_sys->p_cascade );
 132
 133     if( p_filter->p_sys->p_storage )
 134         cvReleaseMemStorage( &p_filter->p_sys->p_storage );
 135
 136     if (NULL != p_filter->p_sys->event_info.p_region)
 137         free(p_filter->p_sys->event_info.p_region);
 138
 139     free( p_sys );
 140
 141     var_Destroy( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE);
 142 }
 143
 144 /****************************************************************************
 145  * Filter: Check for faces and raises an event when one is found.
 146  ****************************************************************************
 147  * p_pic: A picture_t with its p_data_orig member set to an array of
 148  * IplImages (one image for each picture_t plane).
 149  ****************************************************************************/
 150 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 151 {
 152     IplImage** p_img = NULL;
 153     int i_planes = 0;
 154     CvPoint pt1, pt2;
 155     int i, scale = 1;
 156
 157     if ((!p_pic) )
 158     {
 159         msg_Err( p_filter, "no image array" );
 160         return NULL;
 161     }
 162     if (!(p_pic->p_data_orig))
 163     {
 164         msg_Err( p_filter, "no image array" );
 165         return NULL;
 166     }
 167     //(hack) cast the picture_t to array of IplImage*
 168     p_img = (IplImage**) p_pic->p_data_orig;
 169     i_planes = p_pic->i_planes;
 170
 171     //check the image array for validity
 172     if ((!p_img[0]))    //1st plane is 'I' i.e. greyscale
 173     {
 174         msg_Err( p_filter, "no image" );
 175         return NULL;
 176     }
 177     if ((p_pic->format.i_chroma != VLC_FOURCC('I','4','2','0')))
 178     {
 179         msg_Err( p_filter, "wrong chroma - use I420" );
 180         return NULL;
 181     }
 182     if (i_planes<1)
 183     {
 184         msg_Err( p_filter, "no image planes" );
 185         return NULL;
 186     }
 187
 188     //perform face detection
 189     cvClearMemStorage(p_filter->p_sys->p_storage);
 190     CvSeq* faces = NULL;
 191     if( p_filter->p_sys->p_cascade )
 192     {
 193         //we should make some of these params config variables
 194         faces = cvHaarDetectObjects( p_img[0], p_filter->p_sys->p_cascade,
 195             p_filter->p_sys->p_storage, 1.15, 5, CV_HAAR_DO_CANNY_PRUNING,
 196                                             cvSize(20, 20) );
 197         //create the video_filter_region_info_t struct
 198         CvRect* r;
 199         if (faces && (faces->total > 0))
 200         {
 201             //msg_Dbg( p_filter, "Found %d face(s)", faces->total );
 202             if (NULL != p_filter->p_sys->event_info.p_region)
 203             {
 204                 free(p_filter->p_sys->event_info.p_region);
 205                 p_filter->p_sys->event_info.p_region = NULL;
 206             }
 207             if( NULL == ( p_filter->p_sys->event_info.p_region =
 208                   (video_filter_region_info_t *)malloc(faces->total*sizeof(video_filter_region_info_t))))
 209             {
 210                 return NULL;
 211             }
 212             memset(p_filter->p_sys->event_info.p_region, 0, faces->total*sizeof(video_filter_region_info_t));
 213             p_filter->p_sys->event_info.i_region_size = faces->total;
 214         }
 215
 216         //populate the video_filter_region_info_t struct
 217         for( i = 0; i < (faces ? faces->total : 0); i++ )
 218         {
 219             r = (CvRect*)cvGetSeqElem( faces, i );
 220             pt1.x = r->x*scale;
 221             pt2.x = (r->x+r->width)*scale;
 222             pt1.y = r->y*scale;
 223             pt2.y = (r->y+r->height)*scale;
 224             cvRectangle( p_img[0], pt1, pt2, CV_RGB(0,0,0), 3, 8, 0 );
 225
 226             *(CvRect*)(&(p_filter->p_sys->event_info.p_region[i])) = *r;
 227             p_filter->p_sys->event_info.p_region[i].i_id = p_filter->p_sys->i_id++;
 228             p_filter->p_sys->event_info.p_region[i].p_description = "Face Detected";
 229         }
 230
 231         if (faces && (faces->total > 0))    //raise the video filter event
 232             var_TriggerCallback( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE );
 233     }
 234     else
 235         msg_Err( p_filter, "No cascade - is opencv-haarcascade-file valid?" );
 236
 237     return p_pic;
 238 }
 239