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| import cv2, numpy as np | |
| from math import pi | |
| from linpolar_transform import linpolar | |
| from image_utils import stack_imgs_horizontal, stack_imgs_vertical | |
| from draw_utils import draw_points | |
| __fixed_width = 400 | |
| __limb_r_ratios = (0.15, 0.4) | |
| __min_limb_r = int(__fixed_width * __limb_r_ratios[0]) | |
| __max_limb_r = int(__fixed_width * __limb_r_ratios[1]) | |
| __gabor_params = {'ksize':(7, 7), | |
| 'sigma':2, 'theta':pi / 2, | |
| 'lambd':pi * 2, | |
| 'gamma':2, | |
| 'psi':pi / 2, | |
| 'ktype':cv2.CV_32F} | |
| __gabor_kern = cv2.getGaborKernel(**__gabor_params) | |
| __winname = "Limbus Points (filtered polar img)" | |
| __debug_imgs = {} | |
| # eye_img - bgr img of eye ROI | |
| # | phi - angle to ignore at extreme ranges (close to 90 or 270) | |
| # | | angles considered = 360 / angle_step | |
| # | | | | |
| def get_limb_pts(eye_img, phi=20, angle_step=1, debug_index=False): | |
| polar_img_w = 360 / angle_step # Polar image has one column per angle of interest | |
| phi_range_1 = ((90 - phi) / angle_step, (90 + phi) / angle_step) # Ranges of angles to be ignored (too close to lids) | |
| phi_range_2 = ((270 - phi) / angle_step, (270 + phi) / angle_step) | |
| eye_img_grey = cv2.cvtColor(eye_img, cv2.COLOR_BGR2GRAY) # Do BGR-grey | |
| eye_img_grey = cv2.medianBlur(eye_img_grey, 5) | |
| # Scale to fixed size image for re-using transform matrix | |
| scale = eye_img.shape[0] / float(__fixed_width) | |
| img_fixed_size = cv2.resize(eye_img_grey, (__fixed_width, __fixed_width)) | |
| # Transform image into polar coords and blur | |
| img_polar = linpolar(img_fixed_size, trans_w=polar_img_w, trans_h=__fixed_width / 2) | |
| img_polar = cv2.GaussianBlur(img_polar, (5, 5), 0) | |
| # Take the segment between min & max radii and filter with Gabor kernel | |
| img_polar_seg = img_polar[__min_limb_r:__max_limb_r, :] | |
| filter_img = cv2.filter2D(img_polar_seg, -1, __gabor_kern) | |
| # Black out ignored angles | |
| filter_img.T[ phi_range_1[0] : phi_range_1[1] ] = 0 | |
| filter_img.T[ phi_range_2[0] : phi_range_2[1] ] = 0 | |
| # In polar image, x <-> theta, y <-> magnitude | |
| pol_ys = np.argmax(filter_img, axis=0) # Take highest filter response as limbus points | |
| pol_xs = np.arange(filter_img.shape[1])[pol_ys > 0] | |
| mags = (pol_ys + __min_limb_r)[pol_ys > 0] | |
| thts = np.radians(pol_xs * angle_step) | |
| # Translate each point back into fixed img coords | |
| xs, ys = cv2.polarToCart(mags.astype(float), thts) | |
| xs = (xs + __fixed_width / 2) * scale # Shift and scale cart. coords back to original eye-ROI coords | |
| ys = (ys + __fixed_width / 2) * scale | |
| # Points returned in form | |
| # [[ x1 y1] | |
| # [ x2 y2] | |
| # ... | |
| # [ xn yn]] | |
| pts_cart = np.concatenate([xs, ys], axis=1) | |
| # --------------------- Debug Drawing --------------------- | |
| if debug_index != False: | |
| debug_img = eye_img.copy() | |
| debug_polar = cv2.cvtColor(img_polar, cv2.COLOR_GRAY2BGR) | |
| cv2.imwrite("polar.jpg",debug_polar) | |
| cv2.line(debug_polar, (0, __min_limb_r), (img_polar.shape[1], __min_limb_r), (255, 255, 0)) | |
| cv2.line(debug_polar, (0, __max_limb_r), (img_polar.shape[1], __max_limb_r), (255, 255, 0)) | |
| cv2.circle(debug_img, (debug_img.shape[1] / 2, debug_img.shape[0] / 2), int(debug_img.shape[0] * __limb_r_ratios[0]), (255, 255, 0)) | |
| cv2.circle(debug_img, (debug_img.shape[1] / 2, debug_img.shape[0] / 2), int(debug_img.shape[0] * __limb_r_ratios[1]), (255, 255, 0)) | |
| pts_polar = np.squeeze(np.dstack([pol_xs, mags])) | |
| draw_points(debug_polar, pts_polar, (0, 0, 255), width=1) | |
| draw_points(debug_img, pts_cart, (0, 0, 255), width=1) | |
| stacked_imgs_polar = stack_imgs_vertical([debug_polar, filter_img]) | |
| stacked_imgs = stack_imgs_horizontal([debug_img, eye_img_grey, stacked_imgs_polar]) | |
| __debug_imgs[debug_index] = stacked_imgs | |
| if debug_index == 2: | |
| full_debug_img = stack_imgs_vertical([__debug_imgs[1], __debug_imgs[2]]); | |
| cv2.imshow(__winname, full_debug_img) | |
| elif debug_index > 2: | |
| cv2.imshow(__winname, stacked_imgs); | |
| # --------------------- Debug Drawing --------------------- | |
| return pts_cart | |