Add euler to rotation matrix, grid flattening

This commit is contained in:
Piv
2021-08-10 20:39:52 +09:30
parent 8016f0f945
commit df1ac89a81
3 changed files with 110 additions and 52 deletions

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@@ -1,53 +1,42 @@
import numpy as np
import math
import tensorflow as tf
def euler_to_rotation_matrix(x, y, z):
def euler_to_matrix(x, y, z):
"""
:param x: Tensor of shape (B, 1) - x axis rotation
:param y: Tensor of shape (B, 1) - y axis rotation
:param z: Tensor of shape (B, 1) - z axis rotation
:return: Rotation matrix for the given euler anglers, in the order rotation(x).rotation(y).rotation(z)
:return: Rotation matrix for the given euler anglers, in the order rotation(x) -> rotation(y) -> rotation(z)
"""
B = tf.shape(z)[0]
batch_size = tf.shape(z)[0]
# Euler angles should be between -pi and pi, clip so the pose network is coerced to this range
z = tf.clip_by_value(z, -np.pi, np.pi)
y = tf.clip_by_value(y, -np.pi, np.pi)
x = tf.clip_by_value(x, -np.pi, np.pi)
# Expand to B x 1 x 1
z = tf.expand_dims(tf.expand_dims(z, -1), -1)
y = tf.expand_dims(tf.expand_dims(y, -1), -1)
x = tf.expand_dims(tf.expand_dims(x, -1), -1)
zeros = tf.zeros([B, 1, 1])
ones = tf.ones([B, 1, 1])
z = tf.clip_by_value(z, -math.pi, math.pi)
y = tf.clip_by_value(y, -math.pi, math.pi)
x = tf.clip_by_value(x, -math.pi, math.pi)
cosx = tf.cos(x)
sinx = tf.sin(x)
rotx_1 = tf.concat([ones, zeros, zeros], axis=3)
rotx_2 = tf.concat([zeros, cosx, -sinx], axis=3)
rotx_3 = tf.concat([zeros, sinx, cosx], axis=3)
xmat = tf.concat([rotx_1, rotx_2, rotx_3], axis=2)
cosz = tf.cos(z)
sinz = tf.sin(z)
rotz_1 = tf.concat([cosz, -sinz, zeros], axis=3)
rotz_2 = tf.concat([sinz, cosz, zeros], axis=3)
rotz_3 = tf.concat([zeros, zeros, ones], axis=3)
zmat = tf.concat([rotz_1, rotz_2, rotz_3], axis=2)
cosy = tf.cos(y)
siny = tf.sin(y)
roty_1 = tf.concat([cosy, zeros, siny], axis=3)
roty_2 = tf.concat([zeros, ones, zeros], axis=3)
roty_3 = tf.concat([-siny, zeros, cosy], axis=3)
ymat = tf.concat([roty_1, roty_2, roty_3], axis=2)
rotMat = tf.matmul(tf.matmul(xmat, ymat), zmat)
return rotMat
cosz = tf.cos(z)
sinz = tf.sin(z)
# Otherwise this will need to be reversed
# Rotate about x, y then z. z goes first here as rotation is always left side of coordinates
# R = Rz(φ)Ry(θ)Rx(ψ)
# = | cos(θ)cos(φ) sin(ψ)sin(θ)cos(φ) cos(ψ)sin(φ) cos(ψ)sin(θ)cos(φ) + sin(ψ)sin(φ) |
# | cos(θ)sin(φ) sin(ψ)sin(θ)sin(φ) + cos(ψ)cos(φ) cos(ψ)sin(θ)sin(φ) sin(ψ)cos(φ) |
# | sin(θ) sin(ψ)cos(θ) cos(ψ)cos(θ) |
row_1 = tf.concat([cosy * cosz, sinx * siny * cosz - cosx * sinz, cosx * siny * cosz + sinx * sinz], 1)
row_2 = tf.concat([cosy * sinz, sinx * siny * sinz + cosx * cosz, cosx * siny * sinz - sinx * cosz], 1)
row_3 = tf.concat([-siny, sinx * cosy, cosx * cosy], 1)
return tf.reshape(tf.concat([row_1, row_2, row_3], axis=1), [batch_size, 3, 3])
def pose_vec2mat(vec):
@@ -57,13 +46,14 @@ def pose_vec2mat(vec):
Returns:
A transformation matrix -- [B, 4, 4]
"""
# TODO: FIXME
batch_size, _ = vec.get_shape().as_list()
translation = tf.slice(vec, [0, 0], [-1, 3])
translation = tf.expand_dims(translation, -1)
rx = tf.slice(vec, [0, 3], [-1, 1])
ry = tf.slice(vec, [0, 4], [-1, 1])
rz = tf.slice(vec, [0, 5], [-1, 1])
rot_mat = euler_to_rotation_matrix(rx, ry, rz)
rot_mat = euler_to_matrix(rx, ry, rz)
rot_mat = tf.squeeze(rot_mat, axis=[1])
filler = tf.constant([0.0, 0.0, 0.0, 1.0], shape=[1, 1, 4])
filler = tf.tile(filler, [batch_size, 1, 1])
@@ -93,12 +83,23 @@ def image_coordinate(batch, height, width):
return tf.repeat(tf.expand_dims(stacked, axis=0), batch, axis=0)
def intrinsics_vector_to_matrix(intrinsics):
"""
Convert 4 element
:param intrinsics: Tensor of shape (B, 4), intrinsics for each image
:return: Tensor of shape (B, 4, 4), intrinsics for each batch
"""
pass
def projective_inverse_warp(target_img, source_img, depth, pose, intrinsics, coordinates):
"""
Calculate the reprojected image from the source to the target, based on the given depth, pose and intrinsics
SFM Learner inverse warp step
ps ~ K.T(t->s).Dt(pt).K^-1.pt
ps ~ K.T(t->s).Dt(pt)*K^-1.pt
Note that the depth pixel Dt(pt) is multiplied by every coordinate value (just element-wise, not matrix multiplication)
Idea is to map the pixel coordinates of the target image to 3d space (Dt(pt).K^-1.pt), then map these onto
the source image in pixel coordinates (K.T(t->s).{3d coord}), then using the projected coordinates we sample
@@ -108,20 +109,28 @@ def projective_inverse_warp(target_img, source_img, depth, pose, intrinsics, coo
:param source_img: Tensor, same shape as target_img
:param depth: Tensor, (batch, height, width, 1)
:param pose: (batch, 6)
:param intrinsics: (batch, 3, 3)
:param intrinsics: (batch, 4) (fx, fy, px, py) TODO: Intrinsics per image (per source/target image)?
:param coordinates: (batch, height, width, 3) - coordinates for the image. Pass this in so it doesn't need to be
calculated on every warp step
:return: The source image reprojected to the target
"""
# Convert pose vector (output of pose net) to pose matrix (4x4)
pose_4x4 = pose_vec2mat(pose)
# Convert intrinsics matrix (3x3) to (4x4) so it can be multiplied by the pose net
# intrinsics_4x4 =
# Calculate inverse of the 4x4 intrinsics matrix
tf.linalg.inv()
# Create grid of homogenous coordinates
# Create grid (or array?) of homogenous coordinates
grid_coords = image_coordinate(*depth.shape)
# Flatten the image coords to [B, 3, height * width] so each point can be used in calculations
grid_coords = tf.transpose(tf.reshape(grid_coords, [0, 2, 1]))
# Get grid coordinates as array
# Do the function
# sample from the source image using the coordinates applied by the function
#
pass