# complex conjugate

how do i get the complex conjugate??

is the result of cvDFT complex???

```
IplImage * src_img = cvLoadImage("for_fft.jpg", 0);
IplImage * dst_inverse = cvCreateImage(cvGetSize(src_img), IPL_DEPTH_8U, src_img->nChannels);
IplImage * dst_freq = cvCreateImage(cvGetSize(src_img), IPL_DEPTH_8U, src_img->nChannels);
IplImage * dst_swap = cvCreateImage(cvGetSize(src_img), IPL_DEPTH_8U, src_img->nChannels);
//spatial: input, freq: frequency domain
CvMat *spatial = cvCreateMat(src_img->height, src_img->widthStep, CV_64FC2);
CvMat *freq = cvCreateMat(src_img->height, src_img->widthStep, CV_64FC2);
//DFT
for (i = 0; i < src_img->imageSize; i++) {
spatial->data.db[i * 2] = (double)(unsigned char)src_img->imageData[i];
spatial->data.db[i * 2 + 1]; //for complex
}
cvDFT(spatial, freq, CV_DXT_FORWARD);//DFT
//print it out in log scale
double tmp = 0;
double max_f = INT_MIN;
double min_f = INT_MAX;
for (i = 0; i < src_img->imageSize; i++) {
tmp = log10(1 + sqrt(SQUARE(freq->data.db[i * 2]) + SQUARE(freq->data.db[i * 2 + 1])));
if (tmp < min_f)min_f = tmp;
if (tmp > max_f) max_f = tmp;
}
for (i = 0; i < src_img->imageSize; i++) {
dst_freq->imageData[i] = (unsigned char)(256 / (max_f - min_f)*log10(1 + sqrt(SQUARE(freq->data.db[i * 2]) + SQUARE(freq->data.db[i * 2 + 1]))))+5;
}
FreqShift(dst_freq, dst_swap);
cvDFT(freq, spatial, CV_DXT_INVERSE_SCALE);
for (i = 0; i < src_img->imageSize; i++) {
dst_inverse->imageData[i] = (char)spatial->data.db[i * 2];
}
```

this is what i did 2D image dft

i want to get the complex conjugate what should i do ? I just start opencv 5 days ago. please let me know.