1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
#include <iostream>
#include <stdexcept>
#include <opencv2/objdetect.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/imgproc.hpp>
#include <opencv2/imgcodecs.hpp>
#include <opencv2/video.hpp>
#include <opencv2/videoio.hpp>
using namespace cv;
using namespace std;
const char* keys =
{
"{ help h | | print help message }"
"{ image i | | specify input image}"
"{ camera c | | enable camera capturing }"
"{ video v | ../data/vtest.avi | use video as input }"
"{ directory d | | images directory}"
};
static void detectAndDraw(const HOGDescriptor &hog, Mat &img)
{
vector<Rect> found, found_filtered;
double t = (double) getTickCount();
// Run the detector with default parameters. to get a higher hit-rate
// (and more false alarms, respectively), decrease the hitThreshold and
// groupThreshold (set groupThreshold to 0 to turn off the grouping completely).
hog.detectMultiScale(img, found, 0, Size(8,8), Size(32,32), 1.05, 2);
t = (double) getTickCount() - t;
cout << "detection time = " << (t*1000./cv::getTickFrequency()) << " ms" << endl;
for(size_t i = 0; i < found.size(); i++ )
{
Rect r = found[i];
size_t j;
// Do not add small detections inside a bigger detection.
for ( j = 0; j < found.size(); j++ )
if ( j != i && (r & found[j]) == r )
break;
if ( j == found.size() )
found_filtered.push_back(r);
}
for (size_t i = 0; i < found_filtered.size(); i++)
{
Rect r = found_filtered[i];
// The HOG detector returns slightly larger rectangles than the real objects,
// so we slightly shrink the rectangles to get a nicer output.
r.x += cvRound(r.width*0.1);
r.width = cvRound(r.width*0.8);
r.y += cvRound(r.height*0.07);
r.height = cvRound(r.height*0.8);
rectangle(img, r.tl(), r.br(), cv::Scalar(0,255,0), 3);
}
}
int main(int argc, char** argv)
{
CommandLineParser parser(argc, argv, keys);
if (parser.has("help"))
{
cout << "\nThis program demonstrates the use of the HoG descriptor using\n"
" HOGDescriptor::hog.setSVMDetector(HOGDescriptor::getDefaultPeopleDetector());\n";
parser.printMessage();
cout << "During execution:\n\tHit q or ESC key to quit.\n"
"\tUsing OpenCV version " << CV_VERSION << "\n"
"Note: camera device number must be different from -1.\n" << endl;
return 0;
}
HOGDescriptor hog;
hog.setSVMDetector(HOGDescriptor::getDefaultPeopleDetector());
namedWindow("people detector", 1);
string pattern_glob = "";
string video_filename = "../data/vtest.avi";
int camera_id = -1;
if (parser.has("directory"))
{
pattern_glob = parser.get<string>("directory");
}
else if (parser.has("image"))
{
pattern_glob = parser.get<string>("image");
}
else if (parser.has("camera"))
{
camera_id = parser.get<int>("camera");
}
else if (parser.has("video"))
{
video_filename = parser.get<string>("video");
}
if (!pattern_glob.empty() || camera_id != -1 || !video_filename.empty())
{
//Read from input image files
vector<String> filenames;
//Read from video file
VideoCapture vc;
Mat frame;
if (!pattern_glob.empty())
{
String folder(pattern_glob);
glob(folder, filenames);
}
else if (camera_id != -1)
{
vc.open(camera_id);
if (!vc.isOpened())
{
stringstream msg;
msg << "can't open camera: " << camera_id;
throw runtime_error(msg.str());
}
}
else
{
vc.open(video_filename.c_str());
if (!vc.isOpened())
throw runtime_error(string("can't open video file: " + video_filename));
}
vector<String>::const_iterator it_image = filenames.begin();
for (;;)
{
if (!pattern_glob.empty())
{
bool read_image_ok = false;
for (; it_image != filenames.end(); ++it_image)
{
cout << "\nRead: " << *it_image << endl;
// Read current image
frame = imread(*it_image);
if (!frame.empty())
{
++it_image;
read_image_ok = true;
break;
}
}
//No more valid images
if (!read_image_ok)
{
//Release the image in order to exit the while loop
frame.release();
}
}
else
{
vc >> frame;
}
if (frame.empty())
break;
detectAndDraw(hog, frame);
imshow("people detector", frame);
int c = waitKey( vc.isOpened() ? 30 : 0 ) & 255;
if ( c == 'q' || c == 'Q' || c == 27)
break;
}
}
return 0;
}