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) 2006-2012 VLC authors and VideoLAN
   7  * Copyright (C) 2012 Edward Wang
   8  *
   9  * Authors: Dugal Harris <dugalh@protoclea.co.za>
  10  *          Edward Wang <edward.c.wang@compdigitec.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify it
  13  * under the terms of the GNU Lesser General Public License as published by
  14  * the Free Software Foundation; either version 2.1 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  20  * GNU Lesser General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Lesser General Public License
  23  * along with this program; if not, write to the Free Software Foundation,
  24  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  25  *****************************************************************************/
  26
  27 /*****************************************************************************
  28  * Preamble
  29  *****************************************************************************/
  30
  31 #ifdef HAVE_CONFIG_H
  32 # include "config.h"
  33 #endif
  34
  35 #include <vlc_common.h>
  36 #include <vlc_plugin.h>
  37 #include <vlc_filter.h>
  38 #include <vlc_vout.h>
  39 #include <vlc_image.h>
  40 #include "filter_event_info.h"
  41
  42 #include <opencv2/core/core_c.h>
  43 #include <opencv2/core/core.hpp>
  44 #include <opencv2/objdetect/objdetect.hpp>
  45
  46 /*****************************************************************************
  47  * filter_sys_t : filter descriptor
  48  *****************************************************************************/
  49 struct filter_sys_t
  50 {
  51     CvMemStorage* p_storage;
  52     CvHaarClassifierCascade* p_cascade;
  53     video_filter_event_info_t event_info;
  54     int i_id;
  55 };
  56
  57 /****************************************************************************
  58  * Local prototypes
  59  ****************************************************************************/
  60 static int  OpenFilter ( vlc_object_t * );
  61 static void CloseFilter( vlc_object_t * );
  62
  63 static picture_t *Filter( filter_t *, picture_t * );
  64
  65 /*****************************************************************************
  66  * Module descriptor
  67  *****************************************************************************/
  68 vlc_module_begin ()
  69     set_description( N_("OpenCV face detection example filter") )
  70     set_shortname( N_( "OpenCV example" ))
  71     set_capability( "opencv internal filter", 1 )
  72     add_shortcut( "opencv_example" )
  73
  74     set_category( CAT_VIDEO )
  75     set_subcategory( SUBCAT_VIDEO_VFILTER )
  76     set_callbacks( OpenFilter, CloseFilter )
  77
  78     add_string( "opencv-haarcascade-file", "c:\\haarcascade_frontalface_alt.xml",
  79                           N_("Haar cascade filename"),
  80                           N_("Name of XML file containing Haar cascade description"), false);
  81 vlc_module_end ()
  82
  83 /*****************************************************************************
  84  * OpenFilter: probe the filter and return score
  85  *****************************************************************************/
  86 static int OpenFilter( vlc_object_t *p_this )
  87 {
  88     filter_t *p_filter = (filter_t*)p_this;
  89     filter_sys_t *p_sys;
  90
  91     /* Allocate the memory needed to store the decoder's structure */
  92     if( ( p_filter->p_sys = p_sys =
  93           (filter_sys_t *)malloc(sizeof(filter_sys_t)) ) == NULL )
  94     {
  95         return VLC_ENOMEM;
  96     }
  97
  98     //init the video_filter_event_info_t struct
  99     p_sys->event_info.i_region_size = 0;
 100     p_sys->event_info.p_region = NULL;
 101     p_sys->i_id = 0;
 102
 103     p_filter->pf_video_filter = Filter;
 104
 105     //create the VIDEO_FILTER_EVENT_VARIABLE
 106     vlc_value_t val;
 107     if (var_Create( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE, VLC_VAR_ADDRESS | VLC_VAR_DOINHERIT ) != VLC_SUCCESS)
 108         msg_Err( p_filter, "Could not create %s", VIDEO_FILTER_EVENT_VARIABLE);
 109
 110     val.p_address = &(p_sys->event_info);
 111     if (var_Set( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE, val )!=VLC_SUCCESS)
 112         msg_Err( p_filter, "Could not set %s", VIDEO_FILTER_EVENT_VARIABLE);
 113
 114     //OpenCV init specific to this example
 115     char* filename = var_InheritString( p_filter, "opencv-haarcascade-file" );
 116     p_sys->p_cascade = (CvHaarClassifierCascade*)cvLoad( filename, 0, 0, 0 );
 117     p_sys->p_storage = cvCreateMemStorage(0);
 118     free( filename );
 119
 120     return VLC_SUCCESS;
 121 }
 122
 123 /*****************************************************************************
 124  * CloseFilter: clean up the filter
 125  *****************************************************************************/
 126 static void CloseFilter( vlc_object_t *p_this )
 127 {
 128     filter_t *p_filter = (filter_t*)p_this;
 129     filter_sys_t *p_sys = p_filter->p_sys;
 130
 131     if( p_sys->p_cascade )
 132         cvReleaseHaarClassifierCascade( &p_sys->p_cascade );
 133
 134     if( p_sys->p_storage )
 135         cvReleaseMemStorage( &p_sys->p_storage );
 136
 137     free( p_sys->event_info.p_region );
 138     free( p_sys );
 139
 140     var_Destroy( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE);
 141 }
 142
 143 /****************************************************************************
 144  * Filter: Check for faces and raises an event when one is found.
 145  ****************************************************************************/
 146 static picture_t *Filter( filter_t *p_filter, picture_t *p_pic )
 147 {
 148     IplImage** p_img = NULL;
 149     CvPoint pt1, pt2;
 150     int i, scale = 1;
 151     filter_sys_t *p_sys = p_filter->p_sys;
 152
 153     if ((!p_pic) )
 154     {
 155         msg_Err( p_filter, "no image array" );
 156         return NULL;
 157     }
 158     //(hack) cast the picture_t to array of IplImage*
 159     p_img = (IplImage**) p_pic;
 160
 161     //check the image array for validity
 162     if ((!p_img[0]))    //1st plane is 'I' i.e. greyscale
 163     {
 164         msg_Err( p_filter, "no image" );
 165         return NULL;
 166     }
 167
 168     //perform face detection
 169     cvClearMemStorage(p_sys->p_storage);
 170     if( p_sys->p_cascade )
 171     {
 172         //we should make some of these params config variables
 173         CvSeq *faces = cvHaarDetectObjects( p_img[0], p_sys->p_cascade,
 174                                             p_sys->p_storage, 1.15, 5,
 175                                             CV_HAAR_DO_CANNY_PRUNING,
 176                                             cvSize(20, 20) );
 177         //create the video_filter_region_info_t struct
 178         if (faces && (faces->total > 0))
 179         {
 180             //msg_Dbg( p_filter, "Found %d face(s)", faces->total );
 181             free( p_sys->event_info.p_region );
 182             p_sys->event_info.p_region = (video_filter_region_info_t*)
 183                     calloc( faces->total, sizeof(video_filter_region_info_t));
 184             if( !p_sys->event_info.p_region )
 185                 return NULL;
 186             p_sys->event_info.i_region_size = faces->total;
 187         }
 188
 189         //populate the video_filter_region_info_t struct
 190         for( i = 0; i < (faces ? faces->total : 0); i++ )
 191         {
 192             CvRect *r = (CvRect*)cvGetSeqElem( faces, i );
 193             pt1.x = r->x*scale;
 194             pt2.x = (r->x+r->width)*scale;
 195             pt1.y = r->y*scale;
 196             pt2.y = (r->y+r->height)*scale;
 197             cvRectangle( p_img[0], pt1, pt2, CV_RGB(0,0,0), 3, 8, 0 );
 198
 199             *(CvRect*)(&(p_sys->event_info.p_region[i])) = *r;
 200             p_sys->event_info.p_region[i].i_id = p_sys->i_id++;
 201             p_sys->event_info.p_region[i].p_description = "Face Detected";
 202         }
 203
 204         if (faces && (faces->total > 0))    //raise the video filter event
 205             var_TriggerCallback( p_filter->p_libvlc, VIDEO_FILTER_EVENT_VARIABLE );
 206     }
 207     else
 208         msg_Err( p_filter, "No cascade - is opencv-haarcascade-file valid?" );
 209
 210     return p_pic;
 211 }
 212