Files
insightface/reconstruction/ostec/utils/align2stylegan.py
2022-05-29 12:34:47 +01:00

235 lines
9.6 KiB
Python

# Copyright (c) 2020, Baris Gecer. All rights reserved.
#
# This work is made available under the CC BY-NC-SA 4.0.
# To view a copy of this license, see LICENSE
import numpy as np
import scipy.ndimage
import PIL.Image
def create_perspective_transform_matrix(src, dst):
""" Creates a perspective transformation matrix which transforms points
in quadrilateral ``src`` to the corresponding points on quadrilateral
``dst``.
Will raise a ``np.linalg.LinAlgError`` on invalid input.
"""
# See:
# * http://xenia.media.mit.edu/~cwren/interpolator/
# * http://stackoverflow.com/a/14178717/71522
in_matrix = []
for (x, y), (X, Y) in zip(src, dst):
in_matrix.extend([
[x, y, 1, 0, 0, 0, -X * x, -X * y],
[0, 0, 0, x, y, 1, -Y * x, -Y * y],
])
A = np.matrix(in_matrix, dtype=np.float)
B = np.array(dst).reshape(8)
af = np.dot(np.linalg.inv(A.T * A) * A.T, B)
return np.append(np.array(af).reshape(8), 1).reshape((3, 3))
def create_perspective_transform(src, dst, round=False, splat_args=False):
""" Returns a function which will transform points in quadrilateral
``src`` to the corresponding points on quadrilateral ``dst``::
>>> transform = create_perspective_transform(
... [(0, 0), (10, 0), (10, 10), (0, 10)],
... [(50, 50), (100, 50), (100, 100), (50, 100)],
... )
>>> transform((5, 5))
(74.99999999999639, 74.999999999999957)
If ``round`` is ``True`` then points will be rounded to the nearest
integer and integer values will be returned.
>>> transform = create_perspective_transform(
... [(0, 0), (10, 0), (10, 10), (0, 10)],
... [(50, 50), (100, 50), (100, 100), (50, 100)],
... round=True,
... )
>>> transform((5, 5))
(75, 75)
If ``splat_args`` is ``True`` the function will accept two arguments
instead of a tuple.
>>> transform = create_perspective_transform(
... [(0, 0), (10, 0), (10, 10), (0, 10)],
... [(50, 50), (100, 50), (100, 100), (50, 100)],
... splat_args=True,
... )
>>> transform(5, 5)
(74.99999999999639, 74.999999999999957)
If the input values yield an invalid transformation matrix an identity
function will be returned and the ``error`` attribute will be set to a
description of the error::
>>> tranform = create_perspective_transform(
... np.zeros((4, 2)),
... np.zeros((4, 2)),
... )
>>> transform((5, 5))
(5.0, 5.0)
>>> transform.error
'invalid input quads (...): Singular matrix
"""
try:
transform_matrix = create_perspective_transform_matrix(src, dst)
error = None
except np.linalg.LinAlgError as e:
transform_matrix = np.identity(3, dtype=np.float)
error = "invalid input quads (%s and %s): %s" %(src, dst, e)
error = error.replace("\n", "")
to_eval = "def perspective_transform(%s):\n" %(
splat_args and "*pt" or "pt",
)
to_eval += " res = np.dot(transform_matrix, ((pt[0], ), (pt[1], ), (1, )))\n"
to_eval += " res = res / res[2]\n"
if round:
to_eval += " return (int(round(res[0][0])), int(round(res[1][0])))\n"
else:
to_eval += " return (res[0][0], res[1][0])\n"
locals = {
"transform_matrix": transform_matrix,
}
locals.update(globals())
exec(to_eval,locals,locals)
res = locals["perspective_transform"]
res.matrix = transform_matrix
res.error = error
return res
def align_mesh2stylegan(temp_tcoords, transformation_params):
temp_tcoords = temp_tcoords.copy()
temp_tcoords[:, 0] = temp_tcoords[:, 0] - transformation_params['crop'][1]
temp_tcoords[:, 1] = temp_tcoords[:, 1] - transformation_params['crop'][0]
temp_tcoords[:, 0] = temp_tcoords[:, 0] + transformation_params['pad'][1]
temp_tcoords[:, 1] = temp_tcoords[:, 1] + transformation_params['pad'][0]
h, w = (4096, 4096) # transformation_params['new_size']
transform = create_perspective_transform(
transformation_params['quad'],
[(0, 0), (0, h), (h, w), (w, 0)],
splat_args=True,
)
for i in range(len(temp_tcoords)):
temp_tcoords[i, 1], temp_tcoords[i, 0] = transform(temp_tcoords[i, 1], temp_tcoords[i, 0])
new_tcoords = temp_tcoords[:, ::-1] / (h, w) # transformation_params['new_size']
new_tcoords[:, 1] = 1 - new_tcoords[:, 1]
return new_tcoords
def align_im2stylegan(src_im, src_mask, face_landmarks, output_size=1024, transform_size=4096,
enable_padding=True, x_scale=1, y_scale=1, em_scale=0.1, alpha=False):
# Align function from FFHQ dataset pre-processing step
# https://github.com/NVlabs/ffhq-dataset/blob/master/download_ffhq.py
lm = np.array(face_landmarks)
lm_chin = lm[0: 17] # left-right
lm_eyebrow_left = lm[17: 22] # left-right
lm_eyebrow_right = lm[22: 27] # left-right
lm_nose = lm[27: 31] # top-down
lm_nostrils = lm[31: 36] # top-down
lm_eye_left = lm[36: 42] # left-clockwise
lm_eye_right = lm[42: 48] # left-clockwise
lm_mouth_outer = lm[48: 60] # left-clockwise
lm_mouth_inner = lm[60: 68] # left-clockwise
# Calculate auxiliary vectors.
eye_left = np.mean(lm_eye_left, axis=0)
eye_right = np.mean(lm_eye_right, axis=0)
eye_avg = (eye_left + eye_right) * 0.5
eye_to_eye = eye_right - eye_left
mouth_left = lm_mouth_outer[0]
mouth_right = lm_mouth_outer[6]
mouth_avg = (mouth_left + mouth_right) * 0.5
eye_to_mouth = mouth_avg - eye_avg
# Choose oriented crop rectangle.
x = eye_to_eye - np.flipud(eye_to_mouth) * [-1, 1]
x /= np.hypot(*x)
x *= max(np.hypot(*eye_to_eye) * 2.0, np.hypot(*eye_to_mouth) * 1.8)
x *= x_scale
y = np.flipud(x) * [-y_scale, y_scale]
c = eye_avg + eye_to_mouth * em_scale
quad = np.stack([c - x - y, c - x + y, c + x + y, c + x - y])
qsize = np.hypot(*x) * 2
rsize = None
img = src_im.convert('RGBA').convert('RGB')
img_mask = src_mask.convert('L')
img.putalpha(img_mask)
# Shrink.
shrink = int(np.floor(qsize / output_size * 0.5))
if shrink > 1:
rsize = (int(np.rint(float(img.size[0]) / shrink)), int(np.rint(float(img.size[1]) / shrink)))
img = img.resize(rsize, PIL.Image.ANTIALIAS)
quad /= shrink
qsize /= shrink
# Crop.
border = max(int(np.rint(qsize * 0.1)), 3)
crop = (int(np.floor(min(quad[:, 0]))), int(np.floor(min(quad[:, 1]))), int(np.ceil(max(quad[:, 0]))),
int(np.ceil(max(quad[:, 1]))))
crop = (max(crop[0] - border, 0), max(crop[1] - border, 0), min(crop[2] + border, img.size[0]),
min(crop[3] + border, img.size[1]))
if crop[2] - crop[0] < img.size[0] or crop[3] - crop[1] < img.size[1]:
img = img.crop(crop)
quad -= crop[0:2]
# Pad.
pad = (int(np.floor(min(quad[:, 0]))), int(np.floor(min(quad[:, 1]))), int(np.ceil(max(quad[:, 0]))),
int(np.ceil(max(quad[:, 1]))))
pad = (max(-pad[0] + border, 0), max(-pad[1] + border, 0), max(pad[2] - img.size[0] + border, 0),
max(pad[3] - img.size[1] + border, 0))
if enable_padding and max(pad) > border - 4:
pad = np.maximum(pad, int(np.rint(qsize * 0.3)))
img = np.pad(np.float32(img), ((pad[1], pad[3]), (pad[0], pad[2]), (0, 0)), 'constant')
h, w, _ = img.shape
y, x, _ = np.ogrid[:h, :w, :1]
mask = np.maximum(1.0 - np.minimum(np.float32(x) / pad[0], np.float32(w - 1 - x) / pad[2]),
1.0 - np.minimum(np.float32(y) / pad[1], np.float32(h - 1 - y) / pad[3]))
blur = qsize * 0.02
img += (scipy.ndimage.gaussian_filter(img, [blur, blur, 0]) - img) * np.clip(mask * 3.0 + 1.0, 0.0, 1.0)
img += (np.median(img, axis=(0, 1)) - img) * np.clip(mask, 0.0, 1.0)
img = np.uint8(np.clip(np.rint(img), 0, 255))
if alpha:
mask = 1 - np.clip(3.0 * mask, 0.0, 1.0)
mask = np.uint8(np.clip(np.rint(mask * 255), 0, 255))
img = np.concatenate((img, mask), axis=2)
img = PIL.Image.fromarray(img, 'RGBA')
else:
img = PIL.Image.fromarray(img, 'RGBA')
quad += pad[:2]
# Transform.
aligned_mask = PIL.Image.fromarray(np.uint8(img)[:, :, 3])
img = PIL.Image.fromarray(np.uint8(img)[:, :, :3])
img = img.transform((transform_size, transform_size), PIL.Image.QUAD, (quad + 0.5).flatten(),
PIL.Image.BILINEAR)
aligned_mask = aligned_mask.transform((transform_size, transform_size), PIL.Image.QUAD, (quad + 0.5).flatten(),
PIL.Image.BILINEAR)
if output_size < transform_size:
img = img.resize((output_size, output_size), PIL.Image.ANTIALIAS)
aligned_mask = aligned_mask.resize((output_size, output_size), PIL.Image.ANTIALIAS)
transformation_params = {
'rsize': rsize,
'crop': crop,
'pad': pad,
'quad': quad + 0.5,
'new_size': (output_size, output_size)
}
# Save aligned image.
return img, aligned_mask, transformation_params