Hog feature Extraction code (OPENCV processing basic data, C language implementation of basic algorithm) __ block chain

#include <cv.h>
#include #include <math.h>
#include <opencv.hpp>
using namespace CV;
using namespace Std;
Iplimage * Grbtogrey (iplimage* img)//RGB image to grayscale image
{
iplimage* dest=cvcreateimage (Cvsize (Img->width, img->height), img->depth,1);


uchar* data = (uchar*) img->imagedata;
int b,g,r;
for (int i = 0;iheight;i++) {
for (int j = 0;jwidth;j++) {
b = data[i*img->widthstep+j*img->nchannels+0];
g = data[i*img->widthstep+j*img->nchannels+1];
r = data[i*img->widthstep+j*img->nchannels+2];
((uchar*) (Dest->imagedata+i*dest->widthstep)) [J]=0.3*r+0.59*g+0.11*b;
}
}
return dest;
}


iplimage* nomolize (iplimage *img)//Must be a grayscale image
{
uchar* GM = (uchar*) img->imagedata;
int max = 0,min = 255;
for (int i = 0;iheight;i++) {
for (int j = 0;jwidth;j++) {
int num=gm[i*img->widthstep+j*img->nchannels];
if (Num>max) {
max = num;
}
if (num<min) {
min = num;
}
}
}
for (int i = 0;iheight;i++) {
for (int j = 0;jwidth;j++) {
int num = (int) (float) (gm[i*img->widthstep+j*img->nchannels]-min) *
((float) (255)/(float) (max-min);
if (num>255) {
num = 255;
}
((uchar*) (Img->imagedata+i*img->widthstep)) [j] = num;
}
}
return img;
}


Iplimage *greygamma (Iplimage *greyimage) {
Iplimage *gammaimage = Cvcreateimage (Cvsize (greyimage->width,greyimage->height),
Greyimage->depth,greyimage->nchannels);


uchar* data = (uchar*) greyimage->imagedata;
for (int i = 0;i<greyimage->height;i++) {
for (int j = 0;j<greyimage->width;j++) {
int gamma=data[i*greyimage->widthstep+j*greyimage->nchannels];
((uchar*) (Gammaimage->imagedata+i*gammaimage->widthstep)) [j] = (int) sqrt ((float) gamma);
}
}
Return Nomolize (Gammaimage);
}


Iplimage *gradientimg (Iplimage *img) {
UCHAR * data = (uchar*) img->imagedata;
for (int i = 1;iheight-1;i++) {
for (int j = 1;jwidth-1;j++) {
int Gx = data[i*img->widthstep+ (j+1) *img->nchannels]-data[i*img->widthstep+ (j-1) *img->nchannels];
int Gy = data[(i+1) *img->widthstep+j*img->nchannels]-data[(i-1) *img->widthstep+j*img->nchannels];
int gradient = (int) sqrt ((float) (gx*gx+gy*gy));
int theta = (int) (Atan (float) gy/(float) Gx) *180/3.14);
((uchar*) (Img->imagedata+i*img->widthstep)) [j] = theta;
}
}
Return Nomolize (IMG);
}


int *cellfeature (iplimage *img, int w,int h) {//8*8 cell
int cell_w = 8;
int f_n = 9;
int *feature = new Int[f_n];
for (int i = 0;i<f_n;i++) {
f_n = 0;
}
for (int i = h;ifor (int j = w;j<w+cell_w;j++) {
feature[((uchar*) (Img->imagedata+i*img->widthstep)) [j]/40]++;
}
}
return feature;
}


int *hogfeature (Iplimage *img) {


int cell_w = 8;
int CELL_FN = 9;
int cell_wn = img->width/cell_w;
int cell_hn = img->height/cell_w;
int *hog_f = new INT[CELL_WN*CELL_HN*CELL_FN];
int m = 0;


for (int i = 0;i<cell_hn;i++) {
for (int j = 0;j<cell_wn;j++) {
int *feature = Cellfeature (img,j*cell_w,i);
for (int k = 0;k<cell_fn;k++) {
hog_f[m++] = feature[k];
}
}
}


for (int i = 0;i<cell_wn*cell_hn*cell_fn;i++) {
if (i%9==0) {
printf ("\ n");
}
if (i% (2*2*9) ==0) {
printf ("-------------------------------------\ n \ nthe");
}
printf ("%d", hog_f[i]);
}
return hog_f;
}


int main ()
{
Iplimage *img=cvloadimage ("img2.jpg");
if (img==null) {
printf ("IMG is null");
return 0;
}
Cvnamedwindow ("Greyimage");
iplimage* greyimg = Grbtogrey (IMG);
Cvshowimage ("Greyimage", greyimg);
Cvwaitkey ();
Cvnamedwindow ("Gammaimage");
iplimage* gammaimg = Greygamma (greyimg);
Cvshowimage ("Gammaimage", gammaimg);
printf ("Gamma end\n");
Cvwaitkey ();
Cvnamedwindow ("Gradientimage");
iplimage* gradientimage = gradientimg (gammaimg);
Cvshowimage ("Gradientimage", gradientimage);
printf ("Gradient end\n");
Cvwaitkey ();
int *hog_f = Hogfeature (gradientimage);
return 1;
}