EyeTrackVR/RANSACApp/ransac.py
2022-06-05 20:19:39 -07:00

309 lines
12 KiB
Python

import sys
sys.path.append(".")
from config import RansacConfig
from pye3dcustom.detector_3d import CameraModel, Detector3D, DetectorMode
from typing import Union
import queue
import threading
import numpy as np
import cv2
def fit_rotated_ellipse_ransac(
data, iter=80, sample_num=10, offset=80 # 80.0, 10, 80
): # before changing these values, please read up on the ransac algorithm
# However if you want to change any value just know that higher iterations will make processing frames slower
count_max = 0
effective_sample = None
for i in range(iter):
sample = np.random.choice(len(data), sample_num, replace=False)
xs = data[sample][:, 0].reshape(-1, 1)
ys = data[sample][:, 1].reshape(-1, 1)
J = np.mat(
np.hstack((xs * ys, ys**2, xs, ys, np.ones_like(xs, dtype=np.float)))
)
Y = np.mat(-1 * xs**2)
P = (J.T * J).I * J.T * Y
# fitter a*x**2 + b*x*y + c*y**2 + d*x + e*y + f = 0
a = 1.0
b = P[0, 0]
c = P[1, 0]
d = P[2, 0]
e = P[3, 0]
f = P[4, 0]
ellipse_model = (
lambda x, y: a * x**2 + b * x * y + c * y**2 + d * x + e * y + f
)
# thresh
ran_sample = np.array(
[[x, y] for (x, y) in data if np.abs(ellipse_model(x, y)) < offset]
)
if len(ran_sample) > count_max:
count_max = len(ran_sample)
effective_sample = ran_sample
return fit_rotated_ellipse(effective_sample)
def fit_rotated_ellipse(data):
xs = data[:, 0].reshape(-1, 1)
ys = data[:, 1].reshape(-1, 1)
J = np.mat(np.hstack((xs * ys, ys**2, xs, ys, np.ones_like(xs, dtype=np.float))))
Y = np.mat(-1 * xs**2)
P = (J.T * J).I * J.T * Y
a = 1.0
b = P[0, 0]
c = P[1, 0]
d = P[2, 0]
e = P[3, 0]
f = P[4, 0]
theta = 0.5 * np.arctan(b / (a - c))
cx = (2 * c * d - b * e) / (b**2 - 4 * a * c)
cy = (2 * a * e - b * d) / (b**2 - 4 * a * c)
cu = a * cx**2 + b * cx * cy + c * cy**2 - f
w = np.sqrt(
cu
/ (
a * np.cos(theta) ** 2
+ b * np.cos(theta) * np.sin(theta)
+ c * np.sin(theta) ** 2
)
)
h = np.sqrt(
cu
/ (
a * np.sin(theta) ** 2
- b * np.cos(theta) * np.sin(theta)
+ c * np.cos(theta) ** 2
)
)
ellipse_model = lambda x, y: a * x**2 + b * x * y + c * y**2 + d * x + e * y + f
error_sum = np.sum([ellipse_model(x, y) for x, y in data])
return (cx, cy, w, h, theta)
class Ransac:
def __init__(self, config: "RansacConfig", cancellation_event: "threading.Event", capture_queue_incoming: "queue.Queue", image_queue_outgoing: "queue.Queue"):
self.config = config
# Cross-thread communication management
self.capture_queue_incoming = capture_queue_incoming
self.image_queue_outgoing = image_queue_outgoing
self.cancellation_event = cancellation_event
# Image state
self.previous_image = None
self.current_image = None
self.current_frame_number = None
self.current_fps = None
self.threshold_image = None
# Calibration Values
self.xoff = 1
self.yoff = 1
self.eyeoffset = 300 # Keep large in order to recenter correctly
self.eyeoffx = 1
self.setoff = 1
self.xmax = 69420
self.xmin = -69420
self.ymax = 69420
self.ymin = -69420
self.previous_rotation = self.config.rotation_angle
def output_images_and_update(self, grayscale_image, threshold_image):
image_stack = np.concatenate((self.current_image, grayscale_image, threshold_image), axis=1)
self.image_queue_outgoing.put(image_stack)
self.previous_image = self.current_image
self.previous_rotation = self.config.rotation_angle
def capture_crop_rotate_image(self):
# Get our current frame
try:
# Get frame from capture source, crop to ROI
self.current_image = self.current_image[int(self.config.roi_window_y): int(self.config.roi_window_y+self.config.roi_window_h), int(self.config.roi_window_x): int(self.config.roi_window_x+self.config.roi_window_w)]
except:
# Failure to process frame, reuse previous frame.
self.current_image = self.previous_image
print('[ERROR] Frame capture issue detected.')
# Apply rotation to cropped area. For any rotation area outside of the bounds of the image,
# fill with white.
rows, cols, _ = self.current_image.shape
img_center = (cols / 2, rows / 2)
rotation_matrix = cv2.getRotationMatrix2D(img_center, self.config.rotation_angle, 1)
self.current_image = cv2.warpAffine(self.current_image, rotation_matrix, (cols, rows),
borderMode=cv2.BORDER_CONSTANT,
borderValue=(255,255,255))
return True
def run(self):
camera_model = CameraModel(focal_length=self.config.focal_length, resolution=[self.config.roi_window_w, self.config.roi_window_h])
detector_3d = Detector3D(camera=camera_model, long_term_mode=DetectorMode.blocking)
while True:
# Check to make sure we haven't been requested to close
if self.cancellation_event.is_set():
print("Exiting RANSAC thread")
return
# If our ROI configuration has changed, reset our model and detector
if camera_model.resolution != [self.config.roi_window_w, self.config.roi_window_h]:
camera_model = CameraModel(focal_length=self.config.focal_length, resolution=[self.config.roi_window_w, self.config.roi_window_h])
detector_3d = Detector3D(camera=camera_model, long_term_mode=DetectorMode.blocking)
try:
# Wait a bit for images here. If we don't get one, just try again.
(self.current_image, self.current_frame, self.current_fps) = self.capture_queue_incoming.get(block=True, timeout=0.1)
except queue.Empty:
# print("No image available")
continue
if not self.capture_crop_rotate_image():
continue
# Convert the image to grayscale, and set up thresholding. Thresholds here are basically a
# low-pass filter that will set any pixel < the threshold value to 0. Thresholding is user
# configurable in this utility as we're dealing with variable lighting amounts/placement, as
# well as camera positioning and lensing. Therefore everyone's cutoff may be different.
#
# The goal of thresholding settings is to make sure we can ONLY see the pupil. This is why we
# crop the image earlier; it gives us less possible dark area to get confused about in the
# next step.
image_gray = cv2.cvtColor(self.current_image, cv2.COLOR_BGR2GRAY)
_, thresh = cv2.threshold(
image_gray, int(self.config.threshold), 255, cv2.THRESH_BINARY
)
# Set up morphological transforms, for smoothing and clearing the image we get out of the
# thresholding operation. After this, we'd really like to just have a black blob in the middle
# of a bunch of white area.
kernel = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (3, 3))
opening = cv2.morphologyEx(thresh, cv2.MORPH_OPEN, kernel)
closing = cv2.morphologyEx(opening, cv2.MORPH_CLOSE, kernel)
image = 255 - closing
# Now that the image is relatively clean, run contour finding in order to get us our pupil
# boundaries in the 2D context. Ideally, we just get one border.
contours, _ = cv2.findContours(
image, cv2.RETR_TREE, cv2.CHAIN_APPROX_NONE
)
# Find the convex shape based on each contour, and sort the list of them from smallest to
# largest area.
convex_hulls = []
for i in range(len(contours)):
convex_hulls.append(cv2.convexHull(contours[i], False))
# If we have no convex maidens, we have no pupil, and can't progress from here. Dump back to
# using blob tracking.
#
# TODO Reimplement Prohurtz's blob tracking fallback
if len(convex_hulls) == 0:
# print("No contours found, eye not detected, continuing")
# Draw our image and stack it for visual output
cv2.drawContours(image_gray, contours, -1, (255, 0, 0), 1)
self.output_images_and_update(cv2.cvtColor(image_gray, cv2.COLOR_GRAY2BGR), cv2.cvtColor(thresh, cv2.COLOR_GRAY2BGR))
continue
# Find our largest hull, which we expect will probably be the ellipse that represents the 2d
# area for the pupil, which we can use as the search area for the eye in general.
largest_hull = sorted(convex_hulls, key=cv2.contourArea)[-1]
# However eyes are annoyingly three dimensional, so we need to take this ellipse and turn it
# into a curve patch on the surface of a sphere (the eye itself). If it's not a sphere, see your
# ophthalmologist about possible issues with astigmatism.
try:
cx, cy, w, h, theta = fit_rotated_ellipse_ransac(largest_hull.reshape(-1, 2))
except:
# If we don't find anything, fall back to blob tracking.
# print("No ellipse found, eye not detected, continuing")
# Draw our image and stack it for visual output
cv2.drawContours(image_gray, contours, -1, (255, 0, 0), 1)
self.output_images_and_update(cv2.cvtColor(image_gray, cv2.COLOR_GRAY2BGR), cv2.cvtColor(thresh, cv2.COLOR_GRAY2BGR))
continue
# Get axis and angle of the ellipse, using pupil labs 2d algos. The next bit of code ranges
# from somewhat to completely magic, as most of it happens in native libraries (hence passing
# via dicts).
result_2d = {}
result_2d_final = {}
frame_number = self.capture_source.get(cv2.CAP_PROP_POS_FRAMES)
fps = self.capture_source.get(cv2.CAP_PROP_FPS)
result_2d["center"] = (cx, cy)
result_2d["axes"] = (w, h)
result_2d["angle"] = theta * 180.0 / np.pi
result_2d_final["ellipse"] = result_2d
result_2d_final["diameter"] = w
result_2d_final["location"] = (cx, cy)
result_2d_final["confidence"] = 0.99
result_2d_final["timestamp"] = self.current_frame_number / self.current_fps
# Black magic happens here, but after this we have our reprojected pupil/eye, and all we had
# to do was sell our soul to satan and/or C++.
result_3d = detector_3d.update_and_detect(result_2d_final, image_gray)
# Now we have our pupil
ellipse_3d = result_3d["ellipse"]
# And our eyeball that the pupil is on the surface of
projected_sphere = result_3d["projected_sphere"]
# Record our pupil center
exm = ellipse_3d["center"][0]
eym = ellipse_3d["center"][1]
# So now we get the offset of the center of the eyeball
xrl = (cx - projected_sphere["center"][0]) / projected_sphere["axes"][0]
eyey = (cy - projected_sphere["center"][1]) / projected_sphere["axes"][1]
# TODO Reimplement Prohurtz's Center Calibration and Calculations
# Pack our base info to send to VRChat
output_tuple = (-abs(xrl) if xrl >= 0 else abs(xrl),
-abs(eyey) if eyey >= 0 else abs(eyey),
0)
# print(output_tuple)
# Draw our image and stack it for visual output
cv2.drawContours(image_gray, contours, -1, (255, 0, 0), 1)
# draw pupil
try:
cv2.ellipse(
image_gray,
tuple(int(v) for v in ellipse_3d["center"]),
tuple(int(v) for v in ellipse_3d["axes"]),
ellipse_3d["angle"],
0,
360, # start/end angle for drawing
(0, 255, 0), # color (BGR): red
)
except Exception:
# Sometimes we get bogus axes and trying to draw this throws. Ideally we should check for
# validity beforehand, but for now just pass. It usually fixes itself on the next frame.
pass
# draw line from center of eyeball to center of pupil
cv2.line(
image_gray,
tuple(int(v) for v in projected_sphere["center"]),
tuple(int(v) for v in ellipse_3d["center"]),
(0, 255, 0), # color (BGR): red
)
# Shove a concatenated image out to the main GUI thread for rendering
self.output_images_and_update(cv2.cvtColor(image_gray, cv2.COLOR_GRAY2BGR), cv2.cvtColor(thresh, cv2.COLOR_GRAY2BGR))