def align_img_stackreg(img_ref, img, align_flag=1, method='translation'):
'''
:param img_ref: reference image
:param img: image need to align
:param align_flag: 1: will do alignment; 0: output shift list only
:param method:
'translation': x, y shift
'rigid': translation + rotation
'scaled rotation': translation + rotation + scaling
'affine': translation + rotation + scaling + shearing
:return:
align_flag == 1: img_ali, row_shift, col_shift, sr (row_shift and col_shift only valid for translation)
align_flag == 0: row_shift, col_shift, sr (row_shift and col_shift only valid for translation)
'''
if method == 'translation':
sr = StackReg(StackReg.TRANSLATION)
elif method == 'rigid':
sr = StackReg(StackReg.RIGID_BODY)
elif method == 'scaled rotation':
sr = StackReg(StackReg.SCALED_ROTATION)
elif method == 'affine':
sr = StackReg(StackReg.AFFINE)
else:
sr = [[1, 0, 0],[0, 1, 0], [0, 0, 1]]
print('unrecognized align method, no aligning performed')
tmat = sr.register(img_ref, img)
row_shift = -tmat[1, 2]
col_shift = -tmat[0, 2]
if align_flag:
img_ali = sr.transform(img)
return img_ali, row_shift, col_shift, sr
else:
return row_shift, col_shift, sr
def correct_drift(reference, move):
sr = StackReg(StackReg.RIGID_BODY)
transformation_matrix = sr.register(reference, move)
out_rot = sr.transform(move, transformation_matrix)
return out_rot, transformation_matrix
def align_3D_coarse_axes(img_ref, img1, circle_mask_ratio=0.6, axes=0, shift_flag=1):
'''
Aligning the reconstructed tomo with assigned 3D reconstruction along given axis. It will project the 3D data along given axis to find the shifts
Inputs:
-----------
ref: 3D array
data: 3D array need to align
axis: int
along which axis to project the 3D reconstruction to find image shifts
0, or 1, or 2
Output:
----------------
aligned tomo, shfit_matrix
'''
img_tmp = img_ref.copy()
if circle_mask_ratio < 1:
img_ref_crop = pyxas.circ_mask(img_tmp, axis=0, ratio=circle_mask_ratio, val=0)
else:
img_ref_crop = img_tmp.copy()
s = img_ref_crop.shape
stack_range = [int(s[0]*(0.5-circle_mask_ratio/2)), int(s[0]*(0.5+circle_mask_ratio/2))]
prj0 = np.sum(img_ref_crop[stack_range[0]:stack_range[1]], axis=axes)
img_tmp = img1.copy()
if circle_mask_ratio < 1:
img_raw_crop = pyxas.circ_mask(img_tmp, axis=0, ratio=circle_mask_ratio, val=0)
else:
img_raw_crop = img_tmp.copy()
prj1 = np.sum(img_raw_crop[stack_range[0]:stack_range[1]], axis=axes)
sr = StackReg(StackReg.TRANSLATION)
tmat = sr.register(prj0, prj1)
r = -tmat[1, 2]
c = -tmat[0, 2]
if axes == 0:
shift_matrix = np.array([0, r, c])
elif axes == 1:
shift_matrix = np.array([r, 0, c])
elif axes == 2:
shift_matrix = np.array([r, c, 0])
else:
shift_matrix = np.array([0, 0, 0])
if shift_flag:
img_ali = pyxas.shift(img1, shift_matrix, order=0)
return img_ali, shift_matrix
else:
return shift_matrix
class ImageTransformOpticalFlow():
"""
Class written to register stack of images for AET.
Uses correlation based method to determine subpixel shift between predicted and measured images.
Input parameters:
- shape: shape of the image
"""
def __init__(self, shape, method="turboreg"):
self.shape = shape
self.x_lin, self.y_lin = np.meshgrid(np.arange(self.shape[1]), np.arange(self.shape[0]))
self.xy_lin = np.concatenate((self.x_lin[np.newaxis,], self.y_lin[np.newaxis,])).astype('float32')
self.sr = StackReg(StackReg.RIGID_BODY)
def _estimate_single(self, predicted, measured):
assert predicted.shape == self.shape
assert measured.shape == self.shape
aff_mat = self.sr.register(measured, predicted)
tform = transform.AffineTransform(matrix = aff_mat)
measured_warp = transform.warp(measured, tform.inverse, cval = 1.0, order = 5)
transform_final = aff_mat.flatten()[0:6]
return measured_warp, transform_final
def estimate(self, predicted_stack, measured_stack):
assert predicted_stack.shape == measured_stack.shape
transform_vec_list = np.zeros((6,measured_stack.shape[2]), dtype="float32")
#Change from torch array to numpy array
flag_predicted_gpu = predicted_stack.is_cuda
if flag_predicted_gpu:
predicted_stack = predicted_stack.cpu()
flag_measured_gpu = measured_stack.is_cuda
if flag_measured_gpu:
measured_stack = measured_stack.cpu()
predicted_np = np.array(predicted_stack.detach())
measured_np = np.array(measured_stack.detach())
#For each image, estimate the affine transform error
for img_idx in range(measured_np.shape[2]):
measured_np[...,img_idx], transform_vec = self._estimate_single(predicted_np[...,img_idx], \
measured_np[...,img_idx])
transform_vec_list[...,img_idx] = transform_vec
#Change data back to torch tensor format
if flag_predicted_gpu:
predicted_stack = predicted_stack.cuda()
measured_np = torch.tensor(measured_np)
if flag_measured_gpu:
measured_stack = measured_stack.cuda()
measured_np = measured_np.cuda()
return measured_np, torch.tensor(transform_vec_list)
def alignChannels(self):
h, w = self.stackedImage.shape[:2]
gray = cv2.cvtColor(self.stackedImage, cv2.COLOR_BGR2GRAY)
sr = StackReg(StackReg.TRANSLATION)
for i, C in enumerate(cv2.split(self.stackedImage)):
M = sr.register(C, gray)
self.stackedImage[:, :, i] = cv2.warpPerspective(
self.stackedImage[:, :, i],
M, (w, h),
borderMode=cv2.BORDER_REPLICATE)
g.ui.childConn.send("Aligning RGB")
def reg(fix, fix_enface, mov):
#assumes (x,z,y) shape. x and y are same shape
sr = StackReg(StackReg.TRANSLATION) #may need to update to rigid body
#first do enface by rotating and averaging down stack
#this will find x-y shift and just the y-shift will be taken
#rot_fix_mean = np.mean(np.rot90(fix, axes=(0,1)), axis=0)
mov_enface = segment_nfl(mov)
rot_mov = np.rot90(mov, axes=(0, 1))
#rot_mov_mean = np.mean(rot_mov, axis=0)
#do the registration
y_mat = sr.register(fix_enface, mov_enface)
#copy matrix for all frames in moving stack
#probably a more elegant way to do this with reeat or tile, but...
enface_mat = np.zeros((mov.shape[1], 3, 3))
enface_mat[:, 0, 0] = 1
enface_mat[:, 1, 1] = 1
enface_mat[:, 2, 2] = 1
enface_mat[:, 1, -1] = y_mat[1, -1]
y_mov = sr.transform_stack(rot_mov, tmats=enface_mat)
#now do x-z registration
#rotate back to normal orientation
temp_mov = np.rot90(y_mov, axes=(1, 0))
#do the registration
xz_mat = np.zeros((mov.shape[0], 3, 3))
#sr = StackReg(StackReg.AFFINE)
for i, fix_frame, mov_frame in zip(range(mov.shape[0]), fix, temp_mov):
#skip frame if empty with np.all(mov_frame==0)?
tmat = sr.register(fix_frame, mov_frame)
xz_mat[i] = tmat
#do the transform
reg_mov = sr.transform_stack(temp_mov, tmats=xz_mat)
return reg_mov
def camera_registration_transform(path, ref_name, mov_name, method):
print("Registering " + ref_name + " and " + mov_name)
# Generate the Path
ref_path = os.path.join(path, ref_name)
mov_path = os.path.join(path, mov_name)
# load reference and "moved" image
ref_image = imread(ref_path, key=0)
mov_image = imread(mov_path, key=0)
# Specify the type of registration
if method is 'TRANSLATION':
transform_object = StackReg(StackReg.TRANSLATION)
elif method is 'AFFINE':
transform_object = StackReg(StackReg.AFFINE)
elif method is 'RIGID_BODY':
transform_object = StackReg(StackReg.RIGID_BODY)
elif method is 'SCALED_ROTATION':
transform_object = StackReg(StackReg.SCALED_ROTATION)
elif method is 'BILINEAR':
transform_object = StackReg(StackReg.BILINEAR)
else:
print('The registration method you selected is unsupported - options include translation'
', affine, rigid body, scaled rotation, and bilinear')
transform_object.register(ref_image, mov_image)
print(transform_object.get_matrix())
transformed_image = np.uint16(transform_object.transform(mov_image))
# Root Mean Square
score1 = mean_squared_error(ref_image, mov_image)
score2 = mean_squared_error(ref_image, transformed_image)
print("RMS Before Registration = " + str(score1))
print("RMS After Registration = " + str(score2))
return transform_object
def find_rot(fn, thresh=0.05, method=1):
from pystackreg import StackReg
sr = StackReg(StackReg.TRANSLATION)
f = h5py.File(fn, "r")
ang = np.array(list(f["angle"]))
img_bkg = np.squeeze(np.array(f["img_bkg_avg"]))
if np.abs(ang[0]) < np.abs(ang[0] - 90): # e.g, rotate from 0 - 180 deg
tmp = np.abs(ang - ang[0] - 180).argmin()
else: # e.g.,rotate from -90 - 90 deg
tmp = np.abs(ang - np.abs(ang[0])).argmin()
img0 = np.array(list(f["img_tomo"][0]))
img180_raw = np.array(list(f["img_tomo"][tmp]))
f.close()
img0 = img0 / img_bkg
img180_raw = img180_raw / img_bkg
img180 = img180_raw[:, ::-1]
s = np.squeeze(img0.shape)
im1 = -np.log(img0)
im2 = -np.log(img180)
im1[np.isnan(im1)] = 0
im2[np.isnan(im2)] = 0
im1[im1 < thresh] = 0
im2[im2 < thresh] = 0
im1 = medfilt2d(im1, 5)
im2 = medfilt2d(im2, 5)
im1_fft = np.fft.fft2(im1)
im2_fft = np.fft.fft2(im2)
results = dftregistration(im1_fft, im2_fft)
row_shift = results[2]
col_shift = results[3]
rot_cen = s[1] / 2 + col_shift / 2 - 1
tmat = sr.register(im1, im2)
rshft = -tmat[1, 2]
cshft = -tmat[0, 2]
rot_cen0 = s[1] / 2 + cshft / 2 - 1
print(f"rot_cen = {rot_cen} or {rot_cen0}")
if method:
return rot_cen
else:
return rot_cen0
def stack_reg_consecutive_frames(z_reg, top_Z):
T = len(z_reg)
Z, _, _, C = z_reg[0].shape
for t in range(T - 1):
print(f'XY registering t = {t}')
ref = z_reg[0][top_Z, :, :, 1]
target_img = z_reg[t + 1][top_Z, :, :, 1]
sr = StackReg(StackReg.RIGID_BODY)
reg_matrix = sr.register(ref, target_img)
# # Use registration matrix on whole stack
for z in range(Z):
for c in range(3):
z_reg[t + 1][z, :, :, c] = sr.transform(z_reg[t + 1][z, :, :,
c])
return z_reg
def align(frames, reference, transformation, normalize, pa1, pa2, conn):
ref = cv2.imread(g.tmp + "cache/" + reference + ".png",
cv2.IMREAD_GRAYSCALE)
if (pa1 != (0, 0) and pa2 != (0, 0)):
# Processing Area
ref = ref[pa1[1]:pa2[1], pa1[0]:pa2[0]]
sr = StackReg(transformation)
tmats = []
h, w = ref.shape[:2]
scaleFactor = min(1.0, (100 / h))
ref = cv2.resize(ref, (int(w * scaleFactor), int(h * scaleFactor)))
if (normalize):
ref = cv2.normalize(ref,
ref,
alpha=0,
beta=255,
norm_type=cv2.NORM_MINMAX)
i = 0
for frame in frames:
mov = cv2.imread(frame.replace("frames", "cache"),
cv2.IMREAD_GRAYSCALE)
if (pa1 != (0, 0) and pa2 != (0, 0)):
# Processing Area
mov = mov[pa1[1]:pa2[1], pa1[0]:pa2[0]]
mov = cv2.resize(mov, (int(w * scaleFactor), int(h * scaleFactor)))
if (normalize):
mov = cv2.normalize(mov,
mov,
alpha=0,
beta=255,
norm_type=cv2.NORM_MINMAX)
M = sr.register(mov, ref)
M[0][2] /= scaleFactor # X
M[1][2] /= scaleFactor # Y
tmats.append(M)
conn.send("Aligning Frames")
i += 1
return tmats
def process(pth):
print(f'\nProcessing {pth}')
save_pth = pth / 'avg_bscans'
#tmat_pth = pth / 'transformation_matrices'
try:
save_pth.mkdir()
#tmat_pth.mkdir()
except FileExistsError:
ex('Save File for reg stacks or tmats already exists. Delete and re-run.'
)
#tell pystack reg that we will use a translational transformation
#there shouldn't be intra-volume rotation or shear (there might be for rod blink)
sr = StackReg(StackReg.TRANSLATION)
#register to the first slice and output the transfomation matrix without transforming
#iterate through the files in the stacks folder
files = pth.glob('*.tif')
loop_starts = time.time()
for i, file in enumerate(files):
if i == 0:
fixed = io.imread(str(file))
avg_fixed = np.average(fixed, axis=0)
save_name = save_pth / f'avg_{file.name}'
io.imsave(arr=img_as_float32(avg_fixed), fname=str(save_name))
#start_time = time.time()
print(f'Processing: {file}')
#Intravolume registration of the fixed volume
#load first stack and do a 3d gaussian blur with a sigma=1
#str needed for imread, otherwise only one frame is loaded
moving = io.imread(str(file)) #had gauss(), testing
avg_moving = np.average(moving, axis=0)
t_mats = sr.register(gauss(avg_fixed), gauss(avg_moving))
#remove the x shift from all the matrices - horizontal movement isn't relevant here,
#the volume should be acquired quickly enough that this isn't a problem.
t_mats[0, -1] = 0
avg_moving = sr.transform(avg_moving, tmat=t_mats)
#Using previous to see if I could get rid of wigge. Didn't seem to work.
#t_mats = sr.register_stack(gauss(fixed), reference='previous')
#t_mats[:,1,-1] = 0
#fixed = sr.transform_stack(fixed, tmats=t_mats)
#save the register fixed volume in the parent directory for reference
save_name = save_pth / f'avg_{file.name}'
#io.imsave(arr=img_as_uint(fixed), fname=str(save_name))
io.imsave(arr=img_as_float32(avg_moving), fname=str(save_name))
#get fixed out of memory - may not be worth the time?
#print(f'Intravolume registration complete. File saved at {save_name}')
#end_time = time.time()
#print(f'{file} was processed in {(end_time - start_time):.2f}s. \
#\n{((end_time - loop_starts)/60):.2f} minutes have elapsed.')
#de;ete emumerate
#if i==4:
#ex('auto break')
end_time = time.time()
print(f'Run took {(end_time-loop_starts)/60:.2f} minutes')
if use_average:
mov_img = mov_his.read_frame_average(frames_for_average)
else:
mov_img = mov_his.read_frame(0)
del mov_his
print(f"Aligning {mov_img_path}")
# increase the image contrast. this improved the results from stackreg drastically
p2, p98 = np.percentile(mov_img, (2, 98))
mov_img = exposure.rescale_intensity(mov_img, in_range=(p2, p98))
# find the transformation matrix
# we only use rigid body, gives: x shift, y shift, rotation
sreg = StackReg(StackReg.RIGID_BODY)
tmat = sreg.register(ref=ref_img, mov=mov_img)
# if average_over_experiments:
# out_img = sreg.transform(mov=mov_img, tmat=tmat)
# ref_img = np.mean([ref_img, out_img], axis=0)
# apply the matrix to the old ROIs
# this is essentially just:
# src = np.vstack((x, y, np.ones_like(x)))
# dst = src.T @ matrix.T
mov_points = np.copy(ref_points)
mov_points[:, 0:2] = tf.matrix_transform(coords=ref_points[:, 0:2],
matrix=tmat)
# save in netcals image format. import via "load roi (legacy)"
x, y, i = mov_points[:].T
z_stack
#%% Save stack
for idx, img in enumerate(z_stack):
io.imsave(f'/Users/xies/Desktop/z_reg_t{idx}.tif', img.astype(np.int16))
#%% Manual adjustment
t = 8
ref = z_reg[t - 1][ref_z[t - 1], ...]
target_img = z_reg[t][ref_z[t], ...]
sr = StackReg(StackReg.RIGID_BODY)
sr.register(ref, target_img)
target_reg = sr.transform(z_reg[t][ref_z[t], ...])
plt.figure()
io.imshow(ref)
plt.figure()
io.imshow(target_reg - target_reg.min())
# for z in range(z_reg[t].shape[0]):
# z_reg[t][z,...] = sr.transform( z_reg[t][z,...])
# io.imsave(f'/Users/xies/Desktop/z_reg_t{t}.tif',z_reg[t].astype(np.int16))
#%% Try Optic flow
from skimage import registration
from skimage import transform
def align_proj_sub(fn_ref, angle_ref, fn, angle1, binning=2, ratio=0.6, block_list=[], sli=[], ali_method='stackreg'):
# ali_method can be 'stackreg' or 'cross_corr'
num_angle = len(angle1)
theta1 = angle1/180.*np.pi
img1_ali = []
rshft = []
cshft = []
img1_all, eng1, _ = pyxas.retrieve_norm_tomo_image(fn, index=-1, binning=binning, sli=sli)
# img1_all = tomopy.prep.stripe.remove_stripe_fw(img1_all, level=5, wname='db5', sigma=1, pad=True)
for j in range(num_angle):
#sr = StackReg(StackReg.RIGID_BODY)
sr = StackReg(StackReg.TRANSLATION)
if not j%20:
print(f'process file {fn}, angle #{j}/{num_angle}')
ang_index = int(pyxas.find_nearest(angle_ref, angle1[j]))
img0, _, _ = pyxas.retrieve_norm_tomo_image(fn_ref, index=ang_index, binning=binning, sli=sli)
img0 = np.squeeze(img0)
s = img0.shape
ratio_s = 0.5 - ratio / 2
ratio_e = 0.5 + ratio /2
img0 = img0[int(s[0]*ratio_s) : int(s[0]*ratio_e), int(s[1]*ratio_s) : int(s[1]*ratio_e)]
#img1, eng1, _ = pyxas.retrieve_norm_tomo_image(fn, index=j, binning=binning, sli=sli)
img1 = np.squeeze(img1_all[j])
tmp = img1[int(s[0]*ratio_s) : int(s[0]*ratio_e), int(s[1]*ratio_s) : int(s[1]*ratio_e)]
if ali_method == 'stackreg':
tmat = sr.register(img0, tmp)
tmp = sr.transform(img1)
rs, cs = -tmat[1, 2], -tmat[0, 2]
else:
_,rs,cs = pyxas.align_img(img0, tmp)
tmp = pyxas.shift(img1, [rs, cs], order=0)
img1_ali.append(tmp)
rshft.append(rs)
cshft.append(cs)
'''
allow_list = list(set(np.arange(len(angle1))) - set(block_list))
x = angle1/180.0*np.pi
x = x[allow_list]
y = np.array(cshft)[allow_list]
zero_angle_pos = pyxas.find_nearest(theta1, 0)
y0 = y[zero_angle_pos]
y_scale = np.max(np.abs(y-y0))
y = (y - y0)/y_scale
r_fit, phi_fit= fit_cos(x, y, num_iter=6000, learning_rate=0.005)
r_fit *= y_scale
Y_fit = eval_fit_cos(r_fit, phi_fit, theta1)+y0
r_shift_mean = np.mean(np.array(rshft)[allow_list])
for j in range(num_angle):
if not j%20:
print(f'process file {fn}, angle #{j}/{num_angle}')
tmp_mat=np.array([[1,0,-Y_fit[j]],[0,1,-r_shift_mean], [0,0,1]])
img1, eng1, _ = pyxas.retrieve_norm_tomo_image(fn, index=j, binning=binning)
img1 = np.squeeze(img1)
tmp = sr.transform(img1, tmp_mat)
img1_ali.append(tmp)
'''
img1_ali = np.array(img1_ali)
return img1_ali, eng1, rshft, cshft
prev = (img).astype('uint8')
sr = StackReg(StackReg.RIGID_BODY)
for i in range(n_frames - 1):
# Detect feature points in previous frame
im.seek(i)
img = np.array(im)
#img = im#/np.amax(im)*255
curr = (img).astype('uint8')
t0 = time.time()
#Translational transformation
sr.register(prev, curr)
out = sr.transform(curr)
out = out.astype('uint8')
print(np.amax(curr))
print(np.amax(out))
#frame_out = cv2.hconcat([curr, out])
#out = out/np.amax(out)*255
#print(np.amax(out))
#cv2.imshow("Before", curr)
cv2.imshow("After", out)
cv2.waitKey(200)
prev = out
def image_reg(im0, im1, im2reg):
'''Enter function general description + arguments'''
sr = StackReg(StackReg.TRANSLATION)
sr.register(im0, im1)
im_reg = sr.transform(im2reg)
return im_reg
def align(frames, file, reference, referenceIndex, transformation, normalize,
totalFrames, startFrame, dx, dy, aoi1, aoi2, conn):
i = startFrame
tmats = []
minX = minY = maxX = maxY = 0
video = Video()
# Load Reference
refOrig = ref = cv2.cvtColor(video.getFrame(file, reference),
cv2.COLOR_BGR2GRAY)
h1, w1 = ref.shape[:2]
# Drift
rfdx, rfdy, rfdx1, rfdy1 = Align.calcDriftDeltas(dx, dy, referenceIndex,
totalFrames)
ref = ref[int(rfdy1):int(h1 - rfdy), int(rfdx1):int(w1 - rfdx)]
# Area of Interest
ref = cropAreaOfInterest(ref, aoi1, aoi2)
refOrig = cropAreaOfInterest(refOrig, aoi1, aoi2, rfdx1, rfdy1)
if (transformation != -1):
sr = StackReg(transformation)
else:
sr = None
h, w = ref.shape[:2]
scaleFactor = min(1.0, (100 / h))
ref = cv2.resize(ref, (int(w * scaleFactor), int(h * scaleFactor)))
refOrig = cv2.resize(refOrig, (64, 64))
if (normalize):
ref = normalizeImg(ref)
refOrig = normalizeImg(refOrig)
for frame in frames:
try:
# Load Frame
movOrig = mov = cv2.cvtColor(video.getFrame(file, frame),
cv2.COLOR_BGR2GRAY)
# Drift
fdx, fdy, fdx1, fdy1 = Align.calcDriftDeltas(
dx, dy, i, totalFrames)
mov = mov[int(fdy1):int(h1 - fdy), int(fdx1):int(w1 - fdx)]
# Area of Interest
mov = cropAreaOfInterest(mov, aoi1, aoi2)
# Resize
mov = cv2.resize(mov, (int(w * scaleFactor), int(h * scaleFactor)))
if (normalize):
mov = normalizeImg(mov)
# Stack Registration
if (sr is not None):
M = sr.register(mov, ref)
else:
M = np.identity(3)
# Scale back up
M[0][2] /= scaleFactor # X
M[1][2] /= scaleFactor # Y
# Shift the matrix origin to the Area of Interest, and then shift back
M = shiftOrigin(M, aoi1[0], aoi1[1])
# Add drift transform
M[0][2] -= int(fdx1) - int(rfdx1)
M[1][2] -= int(fdy1) - int(rfdy1)
M = shiftOrigin(M, int(fdx1), int(fdy1))
# Apply transformation to small version to check similarity to reference
movOrig = cv2.warpPerspective(movOrig,
M, (w1, h1),
borderMode=cv2.BORDER_REPLICATE)
if (aoi1 != (0, 0) and aoi2 != (0, 0)):
# Area of Interest
movOrig = cropAreaOfInterest(movOrig, aoi1, aoi2, rfdx1, rfdy1)
xFactor = None
yFactor = None
else:
xFactor = 64 / movOrig.shape[1]
yFactor = 64 / movOrig.shape[0]
movOrig = cv2.resize(movOrig, (64, 64))
if (normalize):
movOrig = normalizeImg(movOrig)
# Similarity
diff = calculateDiff(refOrig, movOrig, xFactor, yFactor, M, i)
# Used for auto-crop
minX, maxX, minY, maxY = Align.calcMinMax(M, minX, maxX, minY,
maxY)
tmats.append((frame, M, diff))
except Exception as e:
print(e)
conn.send("Aligning Frames")
i += 1
return (tmats, minX, minY, maxX, maxY)
