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cda88e0 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 | import numpy as np
import math
from abc import ABC
import copy
class camera(ABC):
def __init__(self, hfov, h, w, height=100.0):
self.fov = hfov
self.h = h
self.w = w
self.ori_height = height
self.height = copy.deepcopy(self.ori_height)
self.O = np.array([0.0, self.height, 0.0]) # ray origianl
######################################################################################
""" Abstraction
"""
def align_horizon(self, cur_horizon):
raise NotImplementedError('Not implemented yet')
def C(self):
raise NotImplementedError('Not implemented yet')
def right(self):
raise NotImplementedError('Not implemented yet')
def up(self):
raise NotImplementedError('Not implemented yet')
######################################################################################
def deg2rad(self, d):
return d / 180.0 * 3.1415925
def rad2deg(self, d):
return d / 3.1415925 * 180.0
def get_ray(self, xy):
""" Assume the center is on the top-left corner
"""
u, v = xy
mat = self.get_ABC_mat()
r = np.dot(mat, np.array([u, v, 1.0]).T)
# r = r/np.sqrt(r @ r)
return r
def project(self, xyz):
relative = xyz - self.O
mat = self.get_ABC_mat()
pp = np.dot(np.linalg.inv(mat), relative)
pixel = np.array([pp[0]/pp[2], pp[1]/pp[2]])
return pixel
def xyh2w(self, xyh):
u, v, h = xyh
foot_xyh = np.copy(xyh)
foot_xyh[1] = foot_xyh[1] + foot_xyh[2]
foot_xyh[2] = 0.0
fu, fv, fh = foot_xyh
a = self.right()
b = -self.up()
c = self.C()
mat = self.get_ABC_mat()
w = -self.height/(a[1] * fu + b[1] * fv + c[1])
return w
def xyh2xyz(self, xyh):
u, v, h = xyh
foot_xyh = np.copy(xyh)
foot_xyh[1] = foot_xyh[1] + foot_xyh[2]
foot_xyh[2] = 0.0
fu, fv, fh = foot_xyh
a = self.right()
b = -self.up()
c = self.C()
mat = self.get_ABC_mat()
w = -self.height/(a[1] * fu + b[1] * fv + c[1])
# print('w: {} a*u + b * v + c: {}, b/c: {}/{}, fv: {}'.format(w, a[1] * fu + b[1] * fv + c[1], b, c, fv))
xyz = self.O + np.dot(mat, np.array([u, v, 1.0]).T) * w
# print('w: {}, -{}/{}'.format(w, self.height, a[1] * fu + b[1] * fv + c[1]))
return xyz
def xyz2xyh(self, xyz):
foot_xyz = np.copy(xyz)
foot_xyz[1] = 0.0
foot_xy = self.project(foot_xyz)
xy = self.project(xyz)
ret = np.copy(xyz)
ret[:2] = xy
ret[2] = foot_xy[1] - xy[1]
return ret
def get_ABC_mat(self):
a = self.right()
b = -self.up()
c = self.C()
mat = np.concatenate([a[:, None], b[:,None], c[:, None]], axis=1)
return mat
class pitch_camera(camera):
""" Picth alignment camera
"""
def __init__(self, hfov, h, w, height=100.0):
"""
alignment algorithm:
1. pitch alignment
2. axis alignment
"""
super().__init__(hfov, h, w, height)
self.ori_view = np.array([0.0, 0.0, -1.0])
self.cur_view = np.copy(self.ori_view)
def align_horizon(self, cur_horizon):
""" Given horizon, compute the camera pitch
"""
ref_horizon = self.h / 2
rel_distance = -(ref_horizon - cur_horizon)
focal = self.focal()
pitch = math.atan2(rel_distance, focal)
# construct a rotation matrix
c, s = np.cos(pitch), np.sin(pitch)
rot = np.array([[0, 0, 0], [0, c, -s], [0, s, c]])
# compute the new view vector
img_plane_view = self.ori_view * focal
img_plane_view = rot @ img_plane_view.T
self.cur_view = img_plane_view / math.sqrt(np.dot(img_plane_view, img_plane_view))
def C(self):
return self.view() * self.focal() - 0.5 * self.w * self.right() + 0.5 * self.h * self.up()
def right(self):
return np.array([1.0, 0.0, 0.0])
def up(self):
return np.cross(self.right(), self.view())
def focal(self):
focal = self.w * 0.5 / math.tan(self.deg2rad(self.fov * 0.5))
return focal
def view(self):
return self.cur_view
class axis_camera(camera):
""" Axis alignment camera
"""
def __init__(self, hfov, h, w, height=100.0):
super().__init__(hfov, h, w, height)
focal = self.w * 0.5 / math.tan(self.deg2rad(self.fov * 0.5))
self.up_vec = np.array([0.0, 1.0, 0.0])
self.right_vec = np.array([1.0, 0.0, 0.0])
self.ori_c = np.array([-0.5 * self.w, 0.5 * self.h, -focal])
self.c_vec = np.copy(self.ori_c)
def align_horizon(self, cur_horizon):
""" Given horizon, we move the axis to update the horizon
i.e. we need to change C
"""
ref_horizon = self.h // 2
delta_horizon = cur_horizon - ref_horizon
self.c_vec = self.ori_c + delta_horizon * self.up()
# self.height = self.ori_height + delta_horizon
# self.O = np.array([0.0, self.height, 0.0])
def C(self):
return self.c_vec
def right(self):
return self.right_vec
def up(self):
return self.up_vec
def test(ppc):
xyh = np.array([500, 500, 100.0])
proj_xyz = ppc.xyh2xyz(xyh)
proj_xyh = ppc.xyz2xyh(proj_xyz)
print('xyh: {}, proj xyz: {}, proj xyh: {}'.format(xyh, proj_xyz, proj_xyh))
# import pdb; pdb.set_trace()
new_horizon_list = [0, 100, 250, 400, 500]
new_horizon_list = [100, 250, 400, 500]
# import pdb; pdb.set_trace()
for cur_horizon in new_horizon_list:
ppc.align_horizon(cur_horizon)
test_xyh = np.array([500, cur_horizon, 0])
test_xyz = ppc.xyh2xyz(test_xyh)
# print('{} -> {} -> {}'.format(test_xyh, test_xyz, ppc.xyz2xyh(test_xyz)))
print('{} \t -> {} \t -> {}'.format(test_xyh, test_xyz, ppc.xyz2xyh(test_xyz)))
if __name__ == '__main__':
p_camera = pitch_camera(90.0, 500, 500)
a_camera = axis_camera(90.0, 500, 500)
test(p_camera)
test(a_camera)
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