EasyMocap/easymocap/mytools/camera_utils.py
2022-10-25 20:57:27 +08:00

308 lines
12 KiB
Python

import cv2
import numpy as np
import os
from os.path import join
class FileStorage(object):
def __init__(self, filename, isWrite=False):
version = cv2.__version__
self.major_version = int(version.split('.')[0])
self.second_version = int(version.split('.')[1])
if isWrite:
os.makedirs(os.path.dirname(filename), exist_ok=True)
self.fs = open(filename, 'w')
self.fs.write('%YAML:1.0\r\n')
self.fs.write('---\r\n')
else:
assert os.path.exists(filename), filename
self.fs = cv2.FileStorage(filename, cv2.FILE_STORAGE_READ)
self.isWrite = isWrite
def __del__(self):
if self.isWrite:
self.fs.close()
else:
cv2.FileStorage.release(self.fs)
def _write(self, out):
self.fs.write(out+'\r\n')
def write(self, key, value, dt='mat'):
if dt == 'mat':
self._write('{}: !!opencv-matrix'.format(key))
self._write(' rows: {}'.format(value.shape[0]))
self._write(' cols: {}'.format(value.shape[1]))
self._write(' dt: d')
self._write(' data: [{}]'.format(', '.join(['{:.3f}'.format(i) for i in value.reshape(-1)])))
elif dt == 'list':
self._write('{}:'.format(key))
for elem in value:
self._write(' - "{}"'.format(elem))
def read(self, key, dt='mat'):
if dt == 'mat':
output = self.fs.getNode(key).mat()
elif dt == 'list':
results = []
n = self.fs.getNode(key)
for i in range(n.size()):
val = n.at(i).string()
if val == '':
val = str(int(n.at(i).real()))
if val != 'none':
results.append(val)
output = results
else:
raise NotImplementedError
return output
def close(self):
self.__del__(self)
def read_intri(intri_name):
assert os.path.exists(intri_name), intri_name
intri = FileStorage(intri_name)
camnames = intri.read('names', dt='list')
cameras = {}
for key in camnames:
cam = {}
cam['K'] = intri.read('K_{}'.format(key))
cam['invK'] = np.linalg.inv(cam['K'])
cam['dist'] = intri.read('dist_{}'.format(key))
cameras[key] = cam
return cameras
def write_intri(intri_name, cameras):
if not os.path.exists(os.path.dirname(intri_name)):
os.makedirs(os.path.dirname(intri_name))
intri = FileStorage(intri_name, True)
results = {}
camnames = list(cameras.keys())
intri.write('names', camnames, 'list')
for key_, val in cameras.items():
key = key_.split('.')[0]
K, dist = val['K'], val['dist']
assert K.shape == (3, 3), K.shape
assert dist.shape == (1, 5) or dist.shape == (5, 1) or dist.shape == (1, 4) or dist.shape == (4, 1), dist.shape
intri.write('K_{}'.format(key), K)
intri.write('dist_{}'.format(key), dist.flatten()[None])
def write_extri(extri_name, cameras):
if not os.path.exists(os.path.dirname(extri_name)):
os.makedirs(os.path.dirname(extri_name))
extri = FileStorage(extri_name, True)
results = {}
camnames = list(cameras.keys())
extri.write('names', camnames, 'list')
for key_, val in cameras.items():
key = key_.split('.')[0]
extri.write('R_{}'.format(key), val['Rvec'])
extri.write('Rot_{}'.format(key), val['R'])
extri.write('T_{}'.format(key), val['T'])
return 0
def read_camera(intri_name, extri_name, cam_names=[]):
assert os.path.exists(intri_name), intri_name
assert os.path.exists(extri_name), extri_name
intri = FileStorage(intri_name)
extri = FileStorage(extri_name)
cams, P = {}, {}
cam_names = intri.read('names', dt='list')
for cam in cam_names:
# 内参只读子码流的
cams[cam] = {}
cams[cam]['K'] = intri.read('K_{}'.format( cam))
cams[cam]['invK'] = np.linalg.inv(cams[cam]['K'])
Rvec = extri.read('R_{}'.format(cam))
Tvec = extri.read('T_{}'.format(cam))
assert Rvec is not None, cam
R = cv2.Rodrigues(Rvec)[0]
RT = np.hstack((R, Tvec))
cams[cam]['RT'] = RT
cams[cam]['R'] = R
cams[cam]['Rvec'] = Rvec
cams[cam]['T'] = Tvec
cams[cam]['center'] = - Rvec.T @ Tvec
P[cam] = cams[cam]['K'] @ cams[cam]['RT']
cams[cam]['P'] = P[cam]
cams[cam]['dist'] = intri.read('dist_{}'.format(cam))
cams['basenames'] = cam_names
return cams
def read_cameras(path, intri='intri.yml', extri='extri.yml', subs=[]):
cameras = read_camera(join(path, intri), join(path, extri))
cameras.pop('basenames')
if len(subs) > 0:
cameras = {key:cameras[key].astype(np.float32) for key in subs}
return cameras
def write_camera(camera, path):
from os.path import join
intri_name = join(path, 'intri.yml')
extri_name = join(path, 'extri.yml')
intri = FileStorage(intri_name, True)
extri = FileStorage(extri_name, True)
results = {}
camnames = [key_.split('.')[0] for key_ in camera.keys()]
intri.write('names', camnames, 'list')
extri.write('names', camnames, 'list')
for key_, val in camera.items():
if key_ == 'basenames':
continue
key = key_.split('.')[0]
intri.write('K_{}'.format(key), val['K'])
intri.write('dist_{}'.format(key), val['dist'])
if 'Rvec' not in val.keys():
val['Rvec'] = cv2.Rodrigues(val['R'])[0]
extri.write('R_{}'.format(key), val['Rvec'])
extri.write('Rot_{}'.format(key), val['R'])
extri.write('T_{}'.format(key), val['T'])
def camera_from_img(img):
height, width = img.shape[0], img.shape[1]
# focal = 1.2*max(height, width) # as colmap
focal = 1.2*min(height, width) # as colmap
K = np.array([focal, 0., width/2, 0., focal, height/2, 0. ,0., 1.]).reshape(3, 3)
camera = {'K':K ,'R': np.eye(3), 'T': np.zeros((3, 1)), 'dist': np.zeros((1, 5))}
camera['invK'] = np.linalg.inv(camera['K'])
camera['P'] = camera['K'] @ np.hstack((camera['R'], camera['T']))
return camera
class Undistort:
distortMap = {}
@classmethod
def image(cls, frame, K, dist, sub=None):
if sub is None:
return cv2.undistort(frame, K, dist, None)
else:
if sub not in cls.distortMap.keys():
h, w = frame.shape[:2]
mapx, mapy = cv2.initUndistortRectifyMap(K, dist, None, K, (w,h), 5)
cls.distortMap[sub] = (mapx, mapy)
mapx, mapy = cls.distortMap[sub]
img = cv2.remap(frame, mapx, mapy, cv2.INTER_NEAREST)
return img
@staticmethod
def points(keypoints, K, dist):
# keypoints: (N, 3)
assert len(keypoints.shape) == 2, keypoints.shape
kpts = keypoints[:, None, :2]
kpts = np.ascontiguousarray(kpts)
kpts = cv2.undistortPoints(kpts, K, dist, P=K)
keypoints = np.hstack([kpts[:, 0], keypoints[:, 2:]])
return keypoints
@staticmethod
def bbox(bbox, K, dist):
keypoints = np.array([[bbox[0], bbox[1], 1], [bbox[2], bbox[3], 1]])
kpts = Undistort.points(keypoints, K, dist)
bbox = np.array([kpts[0, 0], kpts[0, 1], kpts[1, 0], kpts[1, 1], bbox[4]])
return bbox
def unproj(kpts, invK):
homo = np.hstack([kpts[:, :2], np.ones_like(kpts[:, :1])])
homo = homo @ invK.T
return np.hstack([homo[:, :2], kpts[:, 2:]])
class UndistortFisheye:
@staticmethod
def image(frame, K, dist):
Knew = K.copy()
frame = cv2.fisheye.undistortImage(frame, K, dist, Knew=Knew)
return frame, Knew
@staticmethod
def points(keypoints, K, dist, Knew):
# keypoints: (N, 3)
assert len(keypoints.shape) == 2, keypoints.shape
kpts = keypoints[:, None, :2]
kpts = np.ascontiguousarray(kpts)
kpts = cv2.fisheye.undistortPoints(kpts, K, dist, P=Knew)
keypoints = np.hstack([kpts[:, 0], keypoints[:, 2:]])
return keypoints
@staticmethod
def bbox(bbox, K, dist, Knew):
keypoints = np.array([[bbox[0], bbox[1], 1], [bbox[2], bbox[3], 1]])
kpts = UndistortFisheye.points(keypoints, K, dist, Knew)
bbox = np.array([kpts[0, 0], kpts[0, 1], kpts[1, 0], kpts[1, 1], bbox[4]])
return bbox
def get_Pall(cameras, camnames):
Pall = np.stack([cameras[cam]['K'] @ np.hstack((cameras[cam]['R'], cameras[cam]['T'])) for cam in camnames])
return Pall
def get_fundamental_matrix(cameras, basenames):
skew_op = lambda x: np.array([[0, -x[2], x[1]], [x[2], 0, -x[0]], [-x[1], x[0], 0]])
fundamental_op = lambda K_0, R_0, T_0, K_1, R_1, T_1: np.linalg.inv(K_0).T @ (
R_0 @ R_1.T) @ K_1.T @ skew_op(K_1 @ R_1 @ R_0.T @ (T_0 - R_0 @ R_1.T @ T_1))
fundamental_RT_op = lambda K_0, RT_0, K_1, RT_1: fundamental_op (K_0, RT_0[:, :3], RT_0[:, 3], K_1,
RT_1[:, :3], RT_1[:, 3] )
F = np.zeros((len(basenames), len(basenames), 3, 3)) # N x N x 3 x 3 matrix
F = {(icam, jcam): np.zeros((3, 3)) for jcam in basenames for icam in basenames}
for icam in basenames:
for jcam in basenames:
F[(icam, jcam)] += fundamental_RT_op(cameras[icam]['K'], cameras[icam]['RT'], cameras[jcam]['K'], cameras[jcam]['RT'])
if F[(icam, jcam)].sum() == 0:
F[(icam, jcam)] += 1e-12 # to avoid nan
return F
def interp_cameras(cameras, keys, step=20, loop=True, allstep=-1, **kwargs):
from scipy.spatial.transform import Rotation as R
from scipy.spatial.transform import Slerp
if allstep != -1:
tall = np.linspace(0., 1., allstep+1)[:-1].reshape(-1, 1, 1)
elif allstep == -1 and loop:
tall = np.linspace(0., 1., 1+step*len(keys))[:-1].reshape(-1, 1, 1)
elif allstep == -1 and not loop:
tall = np.linspace(0., 1., 1+step*(len(keys)-1))[:-1].reshape(-1, 1, 1)
cameras_new = {}
for ik in range(len(keys)):
if ik == len(keys) -1 and not loop:
break
if loop:
start, end = (ik * tall.shape[0])//len(keys), int((ik+1)*tall.shape[0])//len(keys)
print(ik, start, end, tall.shape)
else:
start, end = (ik * tall.shape[0])//(len(keys)-1), int((ik+1)*tall.shape[0])//(len(keys)-1)
t = tall[start:end].copy()
t = (t-t.min())/(t.max()-t.min())
left, right = keys[ik], keys[0 if ik == len(keys)-1 else ik + 1]
camera_left = cameras[left]
camera_right = cameras[right]
# 插值相机中心: center = - R.T @ T
center_l = - camera_left['R'].T @ camera_left['T']
center_r = - camera_right['R'].T @ camera_right['T']
center_l, center_r = center_l[None], center_r[None]
if False:
centers = center_l * (1-t) + center_r * t
else:
# 球面插值
norm_l, norm_r = np.linalg.norm(center_l), np.linalg.norm(center_r)
center_l, center_r = center_l/norm_l, center_r/norm_r
costheta = (center_l*center_r).sum()
sintheta = np.sqrt(1. - costheta**2)
theta = np.arctan2(sintheta, costheta)
centers = (np.sin(theta*(1-t)) * center_l + np.sin(theta * t) * center_r)/sintheta
norm = norm_l * (1-t) + norm_r * t
centers = centers * norm
key_rots = R.from_matrix(np.stack([camera_left['R'], camera_right['R']]))
key_times = [0, 1]
slerp = Slerp(key_times, key_rots)
interp_rots = slerp(t.squeeze()).as_matrix()
# 计算相机T RX + T = 0 => T = - R @ X
T = - np.einsum('bmn,bno->bmo', interp_rots, centers)
K = camera_left['K'] * (1-t) + camera_right['K'] * t
for i in range(T.shape[0]):
cameras_new['{}-{}-{}'.format(left, right, i)] = \
{
'K': K[i],
'dist': np.zeros((1, 5)),
'R': interp_rots[i],
'T': T[i]
}
return cameras_new