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 #include <vlc/vlc.h>
  34 #include <vlc_decoder.h>
  35 #include <vlc_filter.h>
  36 #include "filter_common.h"
  37 #include <vlc_image.h>
  38 #include "filter_event_info.h"
  39
  40 /*****************************************************************************
  41  * filter_sys_t : filter descriptor
  42  *****************************************************************************/
  43 struct filter_sys_t
  44 {
  45     CvMemStorage* p_storage;
  46     CvHaarClassifierCascade* p_cascade;
  47     video_filter_event_info_t event_info;
  48     int i_id;
  49 };
  50
  51 /****************************************************************************
  52  * Local prototypes
  53  ****************************************************************************/
  54 static int  OpenFilter ( vlc_object_t * );
  55 static void CloseFilter( vlc_object_t * );
  56
  57 static picture_t *Filter( filter_t *, picture_t * );
  58
  59 /*****************************************************************************
  60  * Module descriptor
  61  *****************************************************************************/
  62 vlc_module_begin();
  63     set_description( _("OpenCV face detection example filter") );
  64     set_shortname( _( "OpenCV example" ));
  65     set_capability( "opencv example", 1 );
  66     add_shortcut( "opencv_example" );
  67
  68     set_category( CAT_VIDEO );
  69     set_subcategory( SUBCAT_VIDEO_VFILTER2 );
  70     set_callbacks( OpenFilter, CloseFilter );
  71
  72     add_string( "opencv-haarcascade-file", "c:\\haarcascade_frontalface_alt.xml", NULL,
  73                           N_("Haar cascade filename"),
  74                           N_("Name of XML file containing Haar cascade description"), VLC_FALSE);
  75 vlc_module_end();
  76
  77 /*****************************************************************************
  78  * OpenFilter: probe the filter and return score
  79  *****************************************************************************/
  80 static int OpenFilter( vlc_object_t *p_this )
  81 {
  82     filter_t *p_filter = (filter_t*)p_this;
  83     filter_sys_t *p_sys;
  84
  85     /* Allocate the memory needed to store the decoder's structure */
  86     if( ( p_filter->p_sys = p_sys =
  87           (filter_sys_t *)malloc(sizeof(filter_sys_t)) ) == NULL )
  88     {
  89         msg_Err( p_filter, "out of memory" );
  90         return VLC_EGENERIC;
  91     }
  92
  93     //init the video_filter_event_info_t struct
  94     p_sys->event_info.i_region_size = 0;
  95     p_sys->event_info.p_region = NULL;
  96     p_sys->i_id = 0;
  97
  98     p_filter->pf_video_filter = Filter;
  99
 100     //create the VIDEO_FILTER_EVENT_VARIABLE
 101     vlc_value_t val;
 102     if (var_Create( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE, VLC_VAR_ADDRESS | VLC_VAR_DOINHERIT ) != VLC_SUCCESS)
 103         msg_Err( p_filter, "Could not create %s\n", VIDEO_FILTER_EVENT_VARIABLE);
 104
 105     val.p_address = &(p_sys->event_info);
 106     if (var_Set( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE, val )!=VLC_SUCCESS)
 107         msg_Err( p_filter, "Could not set %s\n", VIDEO_FILTER_EVENT_VARIABLE);
 108
 109     //OpenCV init specific to this example
 110     char* filename = config_GetPsz( p_filter, "opencv-haarcascade-file" );
 111     p_filter->p_sys->p_cascade = (CvHaarClassifierCascade*)cvLoad( filename, 0, 0, 0 );
 112     p_filter->p_sys->p_storage = cvCreateMemStorage(0);
 113
 114     return VLC_SUCCESS;
 115 }
 116
 117 /*****************************************************************************
 118  * CloseFilter: clean up the filter
 119  *****************************************************************************/
 120 static void CloseFilter( vlc_object_t *p_this )
 121 {
 122     filter_t *p_filter = (filter_t*)p_this;
 123     filter_sys_t *p_sys = p_filter->p_sys;
 124
 125     if( p_filter->p_sys->p_cascade )
 126         cvReleaseHaarClassifierCascade( &p_filter->p_sys->p_cascade );
 127
 128     if( p_filter->p_sys->p_storage )
 129         cvReleaseMemStorage( &p_filter->p_sys->p_storage );
 130
 131     if (NULL != p_filter->p_sys->event_info.p_region)
 132         free(p_filter->p_sys->event_info.p_region);
 133
 134     free( p_sys );
 135
 136     var_Destroy( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE);
 137 }
 138
 139 /****************************************************************************
 140  * Filter: Check for faces and raises an event when one is found.
 141  ****************************************************************************
 142  * p_pic: A picture_t with its p_data_orig member set to an array of
 143  * IplImages (one image for each picture_t plane).
 144  ****************************************************************************/
 145 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 146 {
 147     IplImage** p_img = NULL;
 148     int i_planes = 0;
 149     CvPoint pt1, pt2;
 150     int i, scale = 1;
 151
 152     if ((!p_pic) )
 153     {
 154         msg_Err( p_filter, "no image array" );
 155         return NULL;
 156     }
 157     if (!(p_pic->p_data_orig))
 158     {
 159         msg_Err( p_filter, "no image array" );
 160         return NULL;
 161     }
 162     //(hack) cast the picture_t to array of IplImage*
 163     p_img = (IplImage**) p_pic->p_data_orig;
 164     i_planes = p_pic->i_planes;
 165
 166     //check the image array for validity
 167     if ((!p_img[0]))    //1st plane is 'I' i.e. greyscale
 168     {
 169         msg_Err( p_filter, "no image" );
 170         return NULL;
 171     }
 172     if ((p_pic->format.i_chroma != VLC_FOURCC('I','4','2','0')))
 173     {
 174         msg_Err( p_filter, "wrong chroma - use I420" );
 175         return NULL;
 176     }
 177     if (i_planes<1)
 178     {
 179         msg_Err( p_filter, "no image planes" );
 180         return NULL;
 181     }
 182
 183     //perform face detection
 184     cvClearMemStorage(p_filter->p_sys->p_storage);
 185     CvSeq* faces = NULL;
 186     if( p_filter->p_sys->p_cascade )
 187     {
 188         //we should make some of these params config variables
 189         faces = cvHaarDetectObjects( p_img[0], p_filter->p_sys->p_cascade,
 190             p_filter->p_sys->p_storage, 1.15, 5, CV_HAAR_DO_CANNY_PRUNING,
 191                                             cvSize(20, 20) );
 192         //create the video_filter_region_info_t struct
 193         CvRect* r;
 194         if (faces && (faces->total > 0))
 195         {
 196             //msg_Dbg( p_filter, "Found %d face(s)\n", faces->total );
 197             if (NULL != p_filter->p_sys->event_info.p_region)
 198             {
 199                 free(p_filter->p_sys->event_info.p_region);
 200                 p_filter->p_sys->event_info.p_region = NULL;
 201             }
 202             if( NULL == ( p_filter->p_sys->event_info.p_region =
 203                   (video_filter_region_info_t *)malloc(faces->total*sizeof(video_filter_region_info_t))))
 204             {
 205                 msg_Err( p_filter, "out of memory" );
 206                 return NULL;
 207             }
 208             memset(p_filter->p_sys->event_info.p_region, 0, faces->total*sizeof(video_filter_region_info_t));
 209             p_filter->p_sys->event_info.i_region_size = faces->total;
 210         }
 211
 212         //populate the video_filter_region_info_t struct
 213         for( i = 0; i < (faces ? faces->total : 0); i++ )
 214         {
 215             r = (CvRect*)cvGetSeqElem( faces, i );
 216             pt1.x = r->x*scale;
 217             pt2.x = (r->x+r->width)*scale;
 218             pt1.y = r->y*scale;
 219             pt2.y = (r->y+r->height)*scale;
 220             cvRectangle( p_img[0], pt1, pt2, CV_RGB(0,0,0), 3, 8, 0 );
 221
 222             *(CvRect*)(&(p_filter->p_sys->event_info.p_region[i])) = *r;
 223             p_filter->p_sys->event_info.p_region[i].i_id = p_filter->p_sys->i_id++;
 224             p_filter->p_sys->event_info.p_region[i].p_description = "Face Detected";
 225         }
 226
 227         if (faces && (faces->total > 0))    //raise the video filter event
 228             var_Change( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE, VLC_VAR_TRIGGER_CALLBACKS, NULL, NULL );
 229     }
 230     else
 231         msg_Err( p_filter, "No cascade - is opencv-haarcascade-file valid?" );
 232
 233     return p_pic;
 234 }
 235