def get_centerline_from_point(input_image, point_file, gap=4, gaussian_kernel=4, remove_tmp_files=1):
# Initialization
fname_anat = input_image
fname_point = point_file
slice_gap = gap
remove_tmp_files = remove_tmp_files
gaussian_kernel = gaussian_kernel
start_time = time()
verbose = 1
# get path of the toolbox
status, path_sct = commands.getstatusoutput("echo $SCT_DIR")
path_sct = sct.slash_at_the_end(path_sct, 1)
# Parameters for debug mode
if param.debug == 1:
sct.printv("\n*** WARNING: DEBUG MODE ON ***\n\t\t\tCurrent working directory: " + os.getcwd(), "warning")
status, path_sct_testing_data = commands.getstatusoutput("echo $SCT_TESTING_DATA_DIR")
fname_anat = path_sct_testing_data + "/t2/t2.nii.gz"
fname_point = path_sct_testing_data + "/t2/t2_centerline_init.nii.gz"
slice_gap = 5
# check existence of input files
sct.check_file_exist(fname_anat)
sct.check_file_exist(fname_point)
# extract path/file/extension
path_anat, file_anat, ext_anat = sct.extract_fname(fname_anat)
path_point, file_point, ext_point = sct.extract_fname(fname_point)
# extract path of schedule file
# TODO: include schedule file in sct
# TODO: check existence of schedule file
file_schedule = path_sct + param.schedule_file
# Get input image orientation
input_image_orientation = get_orientation_3d(fname_anat, filename=True)
# Display arguments
print "\nCheck input arguments..."
print " Anatomical image: " + fname_anat
print " Orientation: " + input_image_orientation
print " Point in spinal cord: " + fname_point
print " Slice gap: " + str(slice_gap)
print " Gaussian kernel: " + str(gaussian_kernel)
print " Degree of polynomial: " + str(param.deg_poly)
# create temporary folder
print ("\nCreate temporary folder...")
path_tmp = "tmp." + strftime("%y%m%d%H%M%S")
sct.create_folder(path_tmp)
print "\nCopy input data..."
sct.run("cp " + fname_anat + " " + path_tmp + "/tmp.anat" + ext_anat)
sct.run("cp " + fname_point + " " + path_tmp + "/tmp.point" + ext_point)
# go to temporary folder
os.chdir(path_tmp)
# convert to nii
im_anat = convert("tmp.anat" + ext_anat, "tmp.anat.nii")
im_point = convert("tmp.point" + ext_point, "tmp.point.nii")
# Reorient input anatomical volume into RL PA IS orientation
print "\nReorient input volume to RL PA IS orientation..."
set_orientation(im_anat, "RPI")
im_anat.setFileName("tmp.anat_orient.nii")
# Reorient binary point into RL PA IS orientation
print "\nReorient binary point into RL PA IS orientation..."
# sct.run(sct.fsloutput + 'fslswapdim tmp.point RL PA IS tmp.point_orient')
set_orientation(im_point, "RPI")
im_point.setFileName("tmp.point_orient.nii")
# Get image dimensions
print "\nGet image dimensions..."
nx, ny, nz, nt, px, py, pz, pt = Image("tmp.anat_orient.nii").dim
print ".. matrix size: " + str(nx) + " x " + str(ny) + " x " + str(nz)
print ".. voxel size: " + str(px) + "mm x " + str(py) + "mm x " + str(pz) + "mm"
# Split input volume
print "\nSplit input volume..."
im_anat_split_list = split_data(im_anat, 2)
file_anat_split = []
for im in im_anat_split_list:
file_anat_split.append(im.absolutepath)
im.save()
im_point_split_list = split_data(im_point, 2)
file_point_split = []
for im in im_point_split_list:
file_point_split.append(im.absolutepath)
im.save()
# Extract coordinates of input point
data_point = Image("tmp.point_orient.nii").data
x_init, y_init, z_init = unravel_index(data_point.argmax(), data_point.shape)
sct.printv("Coordinates of input point: (" + str(x_init) + ", " + str(y_init) + ", " + str(z_init) + ")", verbose)
# Create 2D gaussian mask
sct.printv("\nCreate gaussian mask from point...", verbose)
xx, yy = mgrid[:nx, :ny]
mask2d = zeros((nx, ny))
radius = round(float(gaussian_kernel + 1) / 2) # add 1 because the radius includes the center.
sigma = float(radius)
mask2d = exp(-(((xx - x_init) ** 2) / (2 * (sigma ** 2)) + ((yy - y_init) ** 2) / (2 * (sigma ** 2))))
# Save mask to 2d file
file_mask_split = ["tmp.mask_orient_Z" + str(z).zfill(4) for z in range(0, nz, 1)]
nii_mask2d = Image("tmp.anat_orient_Z0000.nii")
nii_mask2d.data = mask2d
nii_mask2d.setFileName(file_mask_split[z_init] + ".nii")
nii_mask2d.save()
# initialize variables
file_mat = ["tmp.mat_Z" + str(z).zfill(4) for z in range(0, nz, 1)]
file_mat_inv = ["tmp.mat_inv_Z" + str(z).zfill(4) for z in range(0, nz, 1)]
file_mat_inv_cumul = ["tmp.mat_inv_cumul_Z" + str(z).zfill(4) for z in range(0, nz, 1)]
# create identity matrix for initial transformation matrix
fid = open(file_mat_inv_cumul[z_init], "w")
fid.write("%i %i %i %i\n" % (1, 0, 0, 0))
fid.write("%i %i %i %i\n" % (0, 1, 0, 0))
fid.write("%i %i %i %i\n" % (0, 0, 1, 0))
fid.write("%i %i %i %i\n" % (0, 0, 0, 1))
fid.close()
# initialize centerline: give value corresponding to initial point
x_centerline = [x_init]
y_centerline = [y_init]
z_centerline = [z_init]
warning_count = 0
# go up (1), then down (2) in reference to the binary point
for iUpDown in range(1, 3):
if iUpDown == 1:
# z increases
slice_gap_signed = slice_gap
elif iUpDown == 2:
# z decreases
slice_gap_signed = -slice_gap
# reverse centerline (because values will be appended at the end)
x_centerline.reverse()
y_centerline.reverse()
z_centerline.reverse()
# initialization before looping
z_dest = z_init # point given by user
z_src = z_dest + slice_gap_signed
# continue looping if 0 <= z < nz
while 0 <= z_src < nz:
# print current z:
print "z=" + str(z_src) + ":"
# estimate transformation
sct.run(
fsloutput
+ "flirt -in "
+ file_anat_split[z_src]
+ " -ref "
+ file_anat_split[z_dest]
+ " -schedule "
+ file_schedule
+ " -verbose 0 -omat "
+ file_mat[z_src]
+ " -cost normcorr -forcescaling -inweight "
+ file_mask_split[z_dest]
+ " -refweight "
+ file_mask_split[z_dest]
)
# display transfo
status, output = sct.run("cat " + file_mat[z_src])
print output
# check if transformation is bigger than 1.5x slice_gap
tx = float(output.split()[3])
ty = float(output.split()[7])
norm_txy = linalg.norm([tx, ty], ord=2)
if norm_txy > 1.5 * slice_gap:
print "WARNING: Transformation is too large --> using previous one."
warning_count = warning_count + 1
# if previous transformation exists, replace current one with previous one
if os.path.isfile(file_mat[z_dest]):
sct.run("cp " + file_mat[z_dest] + " " + file_mat[z_src])
# estimate inverse transformation matrix
sct.run("convert_xfm -omat " + file_mat_inv[z_src] + " -inverse " + file_mat[z_src])
# compute cumulative transformation
sct.run(
"convert_xfm -omat "
+ file_mat_inv_cumul[z_src]
+ " -concat "
+ file_mat_inv[z_src]
+ " "
+ file_mat_inv_cumul[z_dest]
)
# apply inverse cumulative transformation to initial gaussian mask (to put it in src space)
sct.run(
fsloutput
+ "flirt -in "
+ file_mask_split[z_init]
+ " -ref "
+ file_mask_split[z_init]
+ " -applyxfm -init "
+ file_mat_inv_cumul[z_src]
+ " -out "
+ file_mask_split[z_src]
)
# open inverse cumulative transformation file and generate centerline
fid = open(file_mat_inv_cumul[z_src])
mat = fid.read().split()
x_centerline.append(x_init + float(mat[3]))
y_centerline.append(y_init + float(mat[7]))
z_centerline.append(z_src)
# z_index = z_index+1
# define new z_dest (target slice) and new z_src (moving slice)
z_dest = z_dest + slice_gap_signed
z_src = z_src + slice_gap_signed
# Reconstruct centerline
# ====================================================================================================
# reverse back centerline (because it's been reversed once, so now all values are in the right order)
x_centerline.reverse()
y_centerline.reverse()
z_centerline.reverse()
# fit centerline in the Z-X plane using polynomial function
print "\nFit centerline in the Z-X plane using polynomial function..."
coeffsx = polyfit(z_centerline, x_centerline, deg=param.deg_poly)
polyx = poly1d(coeffsx)
x_centerline_fit = polyval(polyx, z_centerline)
# calculate RMSE
rmse = linalg.norm(x_centerline_fit - x_centerline) / sqrt(len(x_centerline))
# calculate max absolute error
max_abs = max(abs(x_centerline_fit - x_centerline))
print ".. RMSE (in mm): " + str(rmse * px)
print ".. Maximum absolute error (in mm): " + str(max_abs * px)
# fit centerline in the Z-Y plane using polynomial function
print "\nFit centerline in the Z-Y plane using polynomial function..."
coeffsy = polyfit(z_centerline, y_centerline, deg=param.deg_poly)
polyy = poly1d(coeffsy)
y_centerline_fit = polyval(polyy, z_centerline)
# calculate RMSE
rmse = linalg.norm(y_centerline_fit - y_centerline) / sqrt(len(y_centerline))
# calculate max absolute error
max_abs = max(abs(y_centerline_fit - y_centerline))
print ".. RMSE (in mm): " + str(rmse * py)
print ".. Maximum absolute error (in mm): " + str(max_abs * py)
# display
if param.debug == 1:
import matplotlib.pyplot as plt
plt.figure()
plt.plot(z_centerline, x_centerline, ".", z_centerline, x_centerline_fit, "r")
plt.legend(["Data", "Polynomial Fit"])
plt.title("Z-X plane polynomial interpolation")
plt.show()
plt.figure()
plt.plot(z_centerline, y_centerline, ".", z_centerline, y_centerline_fit, "r")
plt.legend(["Data", "Polynomial Fit"])
plt.title("Z-Y plane polynomial interpolation")
plt.show()
# generate full range z-values for centerline
z_centerline_full = [iz for iz in range(0, nz, 1)]
# calculate X and Y values for the full centerline
x_centerline_fit_full = polyval(polyx, z_centerline_full)
y_centerline_fit_full = polyval(polyy, z_centerline_full)
# Generate fitted transformation matrices and write centerline coordinates in text file
print "\nGenerate fitted transformation matrices and write centerline coordinates in text file..."
file_mat_inv_cumul_fit = ["tmp.mat_inv_cumul_fit_z" + str(z).zfill(4) for z in range(0, nz, 1)]
file_mat_cumul_fit = ["tmp.mat_cumul_fit_z" + str(z).zfill(4) for z in range(0, nz, 1)]
fid_centerline = open("tmp.centerline_coordinates.txt", "w")
for iz in range(0, nz, 1):
# compute inverse cumulative fitted transformation matrix
fid = open(file_mat_inv_cumul_fit[iz], "w")
fid.write("%i %i %i %f\n" % (1, 0, 0, x_centerline_fit_full[iz] - x_init))
fid.write("%i %i %i %f\n" % (0, 1, 0, y_centerline_fit_full[iz] - y_init))
fid.write("%i %i %i %i\n" % (0, 0, 1, 0))
fid.write("%i %i %i %i\n" % (0, 0, 0, 1))
fid.close()
# compute forward cumulative fitted transformation matrix
sct.run("convert_xfm -omat " + file_mat_cumul_fit[iz] + " -inverse " + file_mat_inv_cumul_fit[iz])
# write centerline coordinates in x, y, z format
fid_centerline.write(
"%f %f %f\n" % (x_centerline_fit_full[iz], y_centerline_fit_full[iz], z_centerline_full[iz])
)
fid_centerline.close()
# Prepare output data
# ====================================================================================================
# write centerline as text file
for iz in range(0, nz, 1):
# compute inverse cumulative fitted transformation matrix
fid = open(file_mat_inv_cumul_fit[iz], "w")
fid.write("%i %i %i %f\n" % (1, 0, 0, x_centerline_fit_full[iz] - x_init))
fid.write("%i %i %i %f\n" % (0, 1, 0, y_centerline_fit_full[iz] - y_init))
fid.write("%i %i %i %i\n" % (0, 0, 1, 0))
fid.write("%i %i %i %i\n" % (0, 0, 0, 1))
fid.close()
# write polynomial coefficients
savetxt("tmp.centerline_polycoeffs_x.txt", coeffsx)
savetxt("tmp.centerline_polycoeffs_y.txt", coeffsy)
# apply transformations to data
print "\nApply fitted transformation matrices..."
file_anat_split_fit = ["tmp.anat_orient_fit_z" + str(z).zfill(4) for z in range(0, nz, 1)]
file_mask_split_fit = ["tmp.mask_orient_fit_z" + str(z).zfill(4) for z in range(0, nz, 1)]
file_point_split_fit = ["tmp.point_orient_fit_z" + str(z).zfill(4) for z in range(0, nz, 1)]
for iz in range(0, nz, 1):
# forward cumulative transformation to data
sct.run(
fsloutput
+ "flirt -in "
+ file_anat_split[iz]
+ " -ref "
+ file_anat_split[iz]
+ " -applyxfm -init "
+ file_mat_cumul_fit[iz]
+ " -out "
+ file_anat_split_fit[iz]
)
# inverse cumulative transformation to mask
sct.run(
fsloutput
+ "flirt -in "
+ file_mask_split[z_init]
+ " -ref "
+ file_mask_split[z_init]
+ " -applyxfm -init "
+ file_mat_inv_cumul_fit[iz]
+ " -out "
+ file_mask_split_fit[iz]
)
# inverse cumulative transformation to point
sct.run(
fsloutput
+ "flirt -in "
+ file_point_split[z_init]
+ " -ref "
+ file_point_split[z_init]
+ " -applyxfm -init "
+ file_mat_inv_cumul_fit[iz]
+ " -out "
+ file_point_split_fit[iz]
+ " -interp nearestneighbour"
)
# Merge into 4D volume
print "\nMerge into 4D volume..."
# im_anat_list = [Image(fname) for fname in glob.glob('tmp.anat_orient_fit_z*.nii')]
fname_anat_list = glob.glob("tmp.anat_orient_fit_z*.nii")
im_anat_concat = concat_data(fname_anat_list, 2)
im_anat_concat.setFileName("tmp.anat_orient_fit.nii")
im_anat_concat.save()
# im_mask_list = [Image(fname) for fname in glob.glob('tmp.mask_orient_fit_z*.nii')]
fname_mask_list = glob.glob("tmp.mask_orient_fit_z*.nii")
im_mask_concat = concat_data(fname_mask_list, 2)
im_mask_concat.setFileName("tmp.mask_orient_fit.nii")
im_mask_concat.save()
# im_point_list = [Image(fname) for fname in glob.glob('tmp.point_orient_fit_z*.nii')]
fname_point_list = glob.glob("tmp.point_orient_fit_z*.nii")
im_point_concat = concat_data(fname_point_list, 2)
im_point_concat.setFileName("tmp.point_orient_fit.nii")
im_point_concat.save()
# Copy header geometry from input data
print "\nCopy header geometry from input data..."
im_anat = Image("tmp.anat_orient.nii")
im_anat_orient_fit = Image("tmp.anat_orient_fit.nii")
im_mask_orient_fit = Image("tmp.mask_orient_fit.nii")
im_point_orient_fit = Image("tmp.point_orient_fit.nii")
im_anat_orient_fit = copy_header(im_anat, im_anat_orient_fit)
im_mask_orient_fit = copy_header(im_anat, im_mask_orient_fit)
im_point_orient_fit = copy_header(im_anat, im_point_orient_fit)
for im in [im_anat_orient_fit, im_mask_orient_fit, im_point_orient_fit]:
im.save()
# Reorient outputs into the initial orientation of the input image
print "\nReorient the centerline into the initial orientation of the input image..."
set_orientation("tmp.point_orient_fit.nii", input_image_orientation, "tmp.point_orient_fit.nii")
set_orientation("tmp.mask_orient_fit.nii", input_image_orientation, "tmp.mask_orient_fit.nii")
# Generate output file (in current folder)
print "\nGenerate output file (in current folder)..."
os.chdir("..") # come back to parent folder
fname_output_centerline = sct.generate_output_file(
path_tmp + "/tmp.point_orient_fit.nii", file_anat + "_centerline" + ext_anat
)
# Delete temporary files
if remove_tmp_files == 1:
print "\nRemove temporary files..."
sct.run("rm -rf " + path_tmp, error_exit="warning")
# print number of warnings
print "\nNumber of warnings: " + str(
warning_count
) + " (if >10, you should probably reduce the gap and/or increase the kernel size"
# display elapsed time
elapsed_time = time() - start_time
print "\nFinished! \n\tGenerated file: " + fname_output_centerline + "\n\tElapsed time: " + str(
int(round(elapsed_time))
) + "s\n"
def main():
# Initialization
fname_anat = ''
fname_point = ''
slice_gap = param.gap
remove_tmp_files = param.remove_tmp_files
gaussian_kernel = param.gaussian_kernel
start_time = time.time()
verbose = 1
# get path of the toolbox
status, path_sct = commands.getstatusoutput('echo $SCT_DIR')
path_sct = sct.slash_at_the_end(path_sct, 1)
# Parameters for debug mode
if param.debug == 1:
sct.printv('\n*** WARNING: DEBUG MODE ON ***\n\t\t\tCurrent working directory: '+os.getcwd(), 'warning')
status, path_sct_testing_data = commands.getstatusoutput('echo $SCT_TESTING_DATA_DIR')
fname_anat = path_sct_testing_data+'/t2/t2.nii.gz'
fname_point = path_sct_testing_data+'/t2/t2_centerline_init.nii.gz'
slice_gap = 5
else:
# Check input param
try:
opts, args = getopt.getopt(sys.argv[1:],'hi:p:g:r:k:')
except getopt.GetoptError as err:
print str(err)
usage()
if not opts:
usage()
for opt, arg in opts:
if opt == '-h':
usage()
elif opt in ('-i'):
fname_anat = arg
elif opt in ('-p'):
fname_point = arg
elif opt in ('-g'):
slice_gap = int(arg)
elif opt in ('-r'):
remove_tmp_files = int(arg)
elif opt in ('-k'):
gaussian_kernel = int(arg)
# display usage if a mandatory argument is not provided
if fname_anat == '' or fname_point == '':
usage()
# check existence of input files
sct.check_file_exist(fname_anat)
sct.check_file_exist(fname_point)
# extract path/file/extension
path_anat, file_anat, ext_anat = sct.extract_fname(fname_anat)
path_point, file_point, ext_point = sct.extract_fname(fname_point)
# extract path of schedule file
# TODO: include schedule file in sct
# TODO: check existence of schedule file
file_schedule = path_sct + param.schedule_file
# Get input image orientation
input_image_orientation = get_orientation(fname_anat)
# Display arguments
print '\nCheck input arguments...'
print ' Anatomical image: '+fname_anat
print ' Orientation: '+input_image_orientation
print ' Point in spinal cord: '+fname_point
print ' Slice gap: '+str(slice_gap)
print ' Gaussian kernel: '+str(gaussian_kernel)
print ' Degree of polynomial: '+str(param.deg_poly)
# create temporary folder
print('\nCreate temporary folder...')
path_tmp = 'tmp.'+time.strftime("%y%m%d%H%M%S")
sct.create_folder(path_tmp)
print '\nCopy input data...'
sct.run('cp '+fname_anat+ ' '+path_tmp+'/tmp.anat'+ext_anat)
sct.run('cp '+fname_point+ ' '+path_tmp+'/tmp.point'+ext_point)
# go to temporary folder
os.chdir(path_tmp)
# convert to nii
convert('tmp.anat'+ext_anat, 'tmp.anat.nii')
convert('tmp.point'+ext_point, 'tmp.point.nii')
# Reorient input anatomical volume into RL PA IS orientation
print '\nReorient input volume to RL PA IS orientation...'
#sct.run(sct.fsloutput + 'fslswapdim tmp.anat RL PA IS tmp.anat_orient')
set_orientation('tmp.anat.nii', 'RPI', 'tmp.anat_orient.nii')
# Reorient binary point into RL PA IS orientation
print '\nReorient binary point into RL PA IS orientation...'
# sct.run(sct.fsloutput + 'fslswapdim tmp.point RL PA IS tmp.point_orient')
set_orientation('tmp.point.nii', 'RPI', 'tmp.point_orient.nii')
# Get image dimensions
print '\nGet image dimensions...'
nx, ny, nz, nt, px, py, pz, pt = Image('tmp.anat_orient.nii').dim
print '.. matrix size: '+str(nx)+' x '+str(ny)+' x '+str(nz)
print '.. voxel size: '+str(px)+'mm x '+str(py)+'mm x '+str(pz)+'mm'
# Split input volume
print '\nSplit input volume...'
split_data('tmp.anat_orient.nii', 2, '_z')
file_anat_split = ['tmp.anat_orient_z'+str(z).zfill(4) for z in range(0, nz, 1)]
split_data('tmp.point_orient.nii', 2, '_z')
file_point_split = ['tmp.point_orient_z'+str(z).zfill(4) for z in range(0, nz, 1)]
# Extract coordinates of input point
# sct.printv('\nExtract the slice corresponding to z='+str(z_init)+'...', verbose)
#
data_point = Image('tmp.point_orient.nii').data
x_init, y_init, z_init = unravel_index(data_point.argmax(), data_point.shape)
sct.printv('Coordinates of input point: ('+str(x_init)+', '+str(y_init)+', '+str(z_init)+')', verbose)
# Create 2D gaussian mask
sct.printv('\nCreate gaussian mask from point...', verbose)
xx, yy = mgrid[:nx, :ny]
mask2d = zeros((nx, ny))
radius = round(float(gaussian_kernel+1)/2) # add 1 because the radius includes the center.
sigma = float(radius)
mask2d = exp(-(((xx-x_init)**2)/(2*(sigma**2)) + ((yy-y_init)**2)/(2*(sigma**2))))
# Save mask to 2d file
file_mask_split = ['tmp.mask_orient_z'+str(z).zfill(4) for z in range(0,nz,1)]
nii_mask2d = Image('tmp.anat_orient_z0000.nii')
nii_mask2d.data = mask2d
nii_mask2d.setFileName(file_mask_split[z_init]+'.nii')
nii_mask2d.save()
#
# # Get the coordinates of the input point
# print '\nGet the coordinates of the input point...'
# data_point = Image('tmp.point_orient.nii').data
# x_init, y_init, z_init = unravel_index(data_point.argmax(), data_point.shape)
# print '('+str(x_init)+', '+str(y_init)+', '+str(z_init)+')'
# x_init, y_init, z_init = (data > 0).nonzero()
# x_init = x_init[0]
# y_init = y_init[0]
# z_init = z_init[0]
# print '('+str(x_init)+', '+str(y_init)+', '+str(z_init)+')'
#
# numpy.unravel_index(a.argmax(), a.shape)
#
# file = nibabel.load('tmp.point_orient.nii')
# data = file.get_data()
# x_init, y_init, z_init = (data > 0).nonzero()
# x_init = x_init[0]
# y_init = y_init[0]
# z_init = z_init[0]
# print '('+str(x_init)+', '+str(y_init)+', '+str(z_init)+')'
#
# # Extract the slice corresponding to z=z_init
# print '\nExtract the slice corresponding to z='+str(z_init)+'...'
# file_point_split = ['tmp.point_orient_z'+str(z).zfill(4) for z in range(0,nz,1)]
# nii = Image('tmp.point_orient.nii')
# data_crop = nii.data[:, :, z_init:z_init+1]
# nii.data = data_crop
# nii.setFileName(file_point_split[z_init]+'.nii')
# nii.save()
#
# # Create gaussian mask from point
# print '\nCreate gaussian mask from point...'
# file_mask_split = ['tmp.mask_orient_z'+str(z).zfill(4) for z in range(0,nz,1)]
# sct.run(sct.fsloutput+'fslmaths '+file_point_split[z_init]+' -s '+str(gaussian_kernel)+' '+file_mask_split[z_init])
#
# # Obtain max value from mask
# print '\nFind maximum value from mask...'
# file = nibabel.load(file_mask_split[z_init]+'.nii')
# data = file.get_data()
# max_value_mask = numpy.max(data)
# print '..'+str(max_value_mask)
#
# # Normalize mask beween 0 and 1
# print '\nNormalize mask beween 0 and 1...'
# sct.run(sct.fsloutput+'fslmaths '+file_mask_split[z_init]+' -div '+str(max_value_mask)+' '+file_mask_split[z_init])
## Take the square of the mask
#print '\nCalculate the square of the mask...'
#sct.run(sct.fsloutput+'fslmaths '+file_mask_split[z_init]+' -mul '+file_mask_split[z_init]+' '+file_mask_split[z_init])
# initialize variables
file_mat = ['tmp.mat_z'+str(z).zfill(4) for z in range(0,nz,1)]
file_mat_inv = ['tmp.mat_inv_z'+str(z).zfill(4) for z in range(0,nz,1)]
file_mat_inv_cumul = ['tmp.mat_inv_cumul_z'+str(z).zfill(4) for z in range(0,nz,1)]
# create identity matrix for initial transformation matrix
fid = open(file_mat_inv_cumul[z_init], 'w')
fid.write('%i %i %i %i\n' %(1, 0, 0, 0) )
fid.write('%i %i %i %i\n' %(0, 1, 0, 0) )
fid.write('%i %i %i %i\n' %(0, 0, 1, 0) )
fid.write('%i %i %i %i\n' %(0, 0, 0, 1) )
fid.close()
# initialize centerline: give value corresponding to initial point
x_centerline = [x_init]
y_centerline = [y_init]
z_centerline = [z_init]
warning_count = 0
# go up (1), then down (2) in reference to the binary point
for iUpDown in range(1, 3):
if iUpDown == 1:
# z increases
slice_gap_signed = slice_gap
elif iUpDown == 2:
# z decreases
slice_gap_signed = -slice_gap
# reverse centerline (because values will be appended at the end)
x_centerline.reverse()
y_centerline.reverse()
z_centerline.reverse()
# initialization before looping
z_dest = z_init # point given by user
z_src = z_dest + slice_gap_signed
# continue looping if 0 < z < nz
while 0 <= z_src and z_src <= nz-1:
# print current z:
print 'z='+str(z_src)+':'
# estimate transformation
sct.run(fsloutput+'flirt -in '+file_anat_split[z_src]+' -ref '+file_anat_split[z_dest]+' -schedule '+file_schedule+ ' -verbose 0 -omat '+file_mat[z_src]+' -cost normcorr -forcescaling -inweight '+file_mask_split[z_dest]+' -refweight '+file_mask_split[z_dest])
# display transfo
status, output = sct.run('cat '+file_mat[z_src])
print output
# check if transformation is bigger than 1.5x slice_gap
tx = float(output.split()[3])
ty = float(output.split()[7])
norm_txy = linalg.norm([tx, ty],ord=2)
if norm_txy > 1.5*slice_gap:
print 'WARNING: Transformation is too large --> using previous one.'
warning_count = warning_count + 1
# if previous transformation exists, replace current one with previous one
if os.path.isfile(file_mat[z_dest]):
sct.run('cp '+file_mat[z_dest]+' '+file_mat[z_src])
# estimate inverse transformation matrix
sct.run('convert_xfm -omat '+file_mat_inv[z_src]+' -inverse '+file_mat[z_src])
# compute cumulative transformation
sct.run('convert_xfm -omat '+file_mat_inv_cumul[z_src]+' -concat '+file_mat_inv[z_src]+' '+file_mat_inv_cumul[z_dest])
# apply inverse cumulative transformation to initial gaussian mask (to put it in src space)
sct.run(fsloutput+'flirt -in '+file_mask_split[z_init]+' -ref '+file_mask_split[z_init]+' -applyxfm -init '+file_mat_inv_cumul[z_src]+' -out '+file_mask_split[z_src])
# open inverse cumulative transformation file and generate centerline
fid = open(file_mat_inv_cumul[z_src])
mat = fid.read().split()
x_centerline.append(x_init + float(mat[3]))
y_centerline.append(y_init + float(mat[7]))
z_centerline.append(z_src)
#z_index = z_index+1
# define new z_dest (target slice) and new z_src (moving slice)
z_dest = z_dest + slice_gap_signed
z_src = z_src + slice_gap_signed
# Reconstruct centerline
# ====================================================================================================
# reverse back centerline (because it's been reversed once, so now all values are in the right order)
x_centerline.reverse()
y_centerline.reverse()
z_centerline.reverse()
# fit centerline in the Z-X plane using polynomial function
print '\nFit centerline in the Z-X plane using polynomial function...'
coeffsx = polyfit(z_centerline, x_centerline, deg=param.deg_poly)
polyx = poly1d(coeffsx)
x_centerline_fit = polyval(polyx, z_centerline)
# calculate RMSE
rmse = linalg.norm(x_centerline_fit-x_centerline)/sqrt( len(x_centerline) )
# calculate max absolute error
max_abs = max( abs(x_centerline_fit-x_centerline) )
print '.. RMSE (in mm): '+str(rmse*px)
print '.. Maximum absolute error (in mm): '+str(max_abs*px)
# fit centerline in the Z-Y plane using polynomial function
print '\nFit centerline in the Z-Y plane using polynomial function...'
coeffsy = polyfit(z_centerline, y_centerline, deg=param.deg_poly)
polyy = poly1d(coeffsy)
y_centerline_fit = polyval(polyy, z_centerline)
# calculate RMSE
rmse = linalg.norm(y_centerline_fit-y_centerline)/sqrt( len(y_centerline) )
# calculate max absolute error
max_abs = max( abs(y_centerline_fit-y_centerline) )
print '.. RMSE (in mm): '+str(rmse*py)
print '.. Maximum absolute error (in mm): '+str(max_abs*py)
# display
if param.debug == 1:
import matplotlib.pyplot as plt
plt.figure()
plt.plot(z_centerline,x_centerline,'.',z_centerline,x_centerline_fit,'r')
plt.legend(['Data','Polynomial Fit'])
plt.title('Z-X plane polynomial interpolation')
plt.show()
plt.figure()
plt.plot(z_centerline,y_centerline,'.',z_centerline,y_centerline_fit,'r')
plt.legend(['Data','Polynomial Fit'])
plt.title('Z-Y plane polynomial interpolation')
plt.show()
# generate full range z-values for centerline
z_centerline_full = [iz for iz in range(0, nz, 1)]
# calculate X and Y values for the full centerline
x_centerline_fit_full = polyval(polyx, z_centerline_full)
y_centerline_fit_full = polyval(polyy, z_centerline_full)
# Generate fitted transformation matrices and write centerline coordinates in text file
print '\nGenerate fitted transformation matrices and write centerline coordinates in text file...'
file_mat_inv_cumul_fit = ['tmp.mat_inv_cumul_fit_z'+str(z).zfill(4) for z in range(0,nz,1)]
file_mat_cumul_fit = ['tmp.mat_cumul_fit_z'+str(z).zfill(4) for z in range(0,nz,1)]
fid_centerline = open('tmp.centerline_coordinates.txt', 'w')
for iz in range(0, nz, 1):
# compute inverse cumulative fitted transformation matrix
fid = open(file_mat_inv_cumul_fit[iz], 'w')
fid.write('%i %i %i %f\n' %(1, 0, 0, x_centerline_fit_full[iz]-x_init) )
fid.write('%i %i %i %f\n' %(0, 1, 0, y_centerline_fit_full[iz]-y_init) )
fid.write('%i %i %i %i\n' %(0, 0, 1, 0) )
fid.write('%i %i %i %i\n' %(0, 0, 0, 1) )
fid.close()
# compute forward cumulative fitted transformation matrix
sct.run('convert_xfm -omat '+file_mat_cumul_fit[iz]+' -inverse '+file_mat_inv_cumul_fit[iz])
# write centerline coordinates in x, y, z format
fid_centerline.write('%f %f %f\n' %(x_centerline_fit_full[iz], y_centerline_fit_full[iz], z_centerline_full[iz]) )
fid_centerline.close()
# Prepare output data
# ====================================================================================================
# write centerline as text file
for iz in range(0, nz, 1):
# compute inverse cumulative fitted transformation matrix
fid = open(file_mat_inv_cumul_fit[iz], 'w')
fid.write('%i %i %i %f\n' %(1, 0, 0, x_centerline_fit_full[iz]-x_init) )
fid.write('%i %i %i %f\n' %(0, 1, 0, y_centerline_fit_full[iz]-y_init) )
fid.write('%i %i %i %i\n' %(0, 0, 1, 0) )
fid.write('%i %i %i %i\n' %(0, 0, 0, 1) )
fid.close()
# write polynomial coefficients
savetxt('tmp.centerline_polycoeffs_x.txt',coeffsx)
savetxt('tmp.centerline_polycoeffs_y.txt',coeffsy)
# apply transformations to data
print '\nApply fitted transformation matrices...'
file_anat_split_fit = ['tmp.anat_orient_fit_z'+str(z).zfill(4) for z in range(0,nz,1)]
file_mask_split_fit = ['tmp.mask_orient_fit_z'+str(z).zfill(4) for z in range(0,nz,1)]
file_point_split_fit = ['tmp.point_orient_fit_z'+str(z).zfill(4) for z in range(0,nz,1)]
for iz in range(0, nz, 1):
# forward cumulative transformation to data
sct.run(fsloutput+'flirt -in '+file_anat_split[iz]+' -ref '+file_anat_split[iz]+' -applyxfm -init '+file_mat_cumul_fit[iz]+' -out '+file_anat_split_fit[iz])
# inverse cumulative transformation to mask
sct.run(fsloutput+'flirt -in '+file_mask_split[z_init]+' -ref '+file_mask_split[z_init]+' -applyxfm -init '+file_mat_inv_cumul_fit[iz]+' -out '+file_mask_split_fit[iz])
# inverse cumulative transformation to point
sct.run(fsloutput+'flirt -in '+file_point_split[z_init]+' -ref '+file_point_split[z_init]+' -applyxfm -init '+file_mat_inv_cumul_fit[iz]+' -out '+file_point_split_fit[iz]+' -interp nearestneighbour')
# Merge into 4D volume
print '\nMerge into 4D volume...'
# sct.run(fsloutput+'fslmerge -z tmp.anat_orient_fit tmp.anat_orient_fit_z*')
# sct.run(fsloutput+'fslmerge -z tmp.mask_orient_fit tmp.mask_orient_fit_z*')
# sct.run(fsloutput+'fslmerge -z tmp.point_orient_fit tmp.point_orient_fit_z*')
concat_data(glob.glob('tmp.anat_orient_fit_z*.nii'), 'tmp.anat_orient_fit.nii', dim=2)
concat_data(glob.glob('tmp.mask_orient_fit_z*.nii'), 'tmp.mask_orient_fit.nii', dim=2)
concat_data(glob.glob('tmp.point_orient_fit_z*.nii'), 'tmp.point_orient_fit.nii', dim=2)
# Copy header geometry from input data
print '\nCopy header geometry from input data...'
copy_header('tmp.anat_orient.nii', 'tmp.anat_orient_fit.nii')
copy_header('tmp.anat_orient.nii', 'tmp.mask_orient_fit.nii')
copy_header('tmp.anat_orient.nii', 'tmp.point_orient_fit.nii')
# Reorient outputs into the initial orientation of the input image
print '\nReorient the centerline into the initial orientation of the input image...'
set_orientation('tmp.point_orient_fit.nii', input_image_orientation, 'tmp.point_orient_fit.nii')
set_orientation('tmp.mask_orient_fit.nii', input_image_orientation, 'tmp.mask_orient_fit.nii')
# Generate output file (in current folder)
print '\nGenerate output file (in current folder)...'
os.chdir('..') # come back to parent folder
#sct.generate_output_file('tmp.centerline_polycoeffs_x.txt','./','centerline_polycoeffs_x','.txt')
#sct.generate_output_file('tmp.centerline_polycoeffs_y.txt','./','centerline_polycoeffs_y','.txt')
#sct.generate_output_file('tmp.centerline_coordinates.txt','./','centerline_coordinates','.txt')
#sct.generate_output_file('tmp.anat_orient.nii','./',file_anat+'_rpi',ext_anat)
#sct.generate_output_file('tmp.anat_orient_fit.nii', file_anat+'_rpi_align'+ext_anat)
#sct.generate_output_file('tmp.mask_orient_fit.nii', file_anat+'_mask'+ext_anat)
fname_output_centerline = sct.generate_output_file(path_tmp+'/tmp.point_orient_fit.nii', file_anat+'_centerline'+ext_anat)
# Delete temporary files
if remove_tmp_files == 1:
print '\nRemove temporary files...'
sct.run('rm -rf '+path_tmp)
# print number of warnings
print '\nNumber of warnings: '+str(warning_count)+' (if >10, you should probably reduce the gap and/or increase the kernel size'
# display elapsed time
elapsed_time = time.time() - start_time
print '\nFinished! \n\tGenerated file: '+fname_output_centerline+'\n\tElapsed time: '+str(int(round(elapsed_time)))+'s\n'
