Opencv Android Extract Match Mat After Feature Detection

I want to extract the part of the image that matches my reference image. I try to transform the image using the Calib3d.findHomography method. When i have done this i use Imgproc.w

Solution 1:

I think you should use WARP_INVERSE_MAP as the flag of warpPerspective as: Imgproc.warpPerspective(src, quad, homography, quad.size(),WARP_INVERSE_MAP);.

I have not used exactly your code, but just the part after homography, and i have seen that the image was warped in the mirror, not as we wanted (use a bigger display image to see exactly what's there). In fact, on the page you posted, with the 10-card, it is used that flag, sorry that I have not thought of mentioning this earlier.