-
Notifications
You must be signed in to change notification settings - Fork 27
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Merge pull request #7 from OSIPI/main
add abdominal phantom
- Loading branch information
Showing
9 changed files
with
290 additions
and
11 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
|
@@ -2,4 +2,9 @@ numpy | |
scipy | ||
torchio | ||
torch | ||
logging | ||
logging | ||
joblib | ||
dipy | ||
matplotlib | ||
scienceplots | ||
cvxpy |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,86 @@ | ||
import numpy as np | ||
import numpy.polynomial.polynomial as poly | ||
|
||
from utils.data_simulation.GenerateData import GenerateData | ||
|
||
|
||
|
||
class LinearFit: | ||
""" | ||
Performs linear fits of exponential data | ||
""" | ||
def __init__(self, linear_cutoff=500): | ||
""" | ||
Parameters | ||
---------- | ||
linear_cutoff : float | ||
The b-value after which it can be assumed that the perfusion value is negligible | ||
""" | ||
self.linear_cutoff = linear_cutoff | ||
|
||
def linear_fit(self, bvalues, signal, weighting=None, stats=False): | ||
""" | ||
Fit a single line | ||
Parameters | ||
---------- | ||
bvalues : list or array of float | ||
The diffusion (b-values) | ||
signal : list or array of float | ||
The acquired signal to fit. It is assumed to be linearized at this point. | ||
weighting : list or array fo float | ||
Weights to pass into polyfit. None is no weighting. | ||
stats : boolean | ||
If true, return the polyfit statistics | ||
""" | ||
assert bvalues.size == signal.size, "Signal and b-values don't have the same number of values" | ||
if stats: | ||
D, stats = poly.polyfit(np.asarray(bvalues), signal, 1, full=True, w=weighting) | ||
return [np.exp(D[0]), *-D[1:]], stats | ||
else: | ||
D = poly.polyfit(np.asarray(bvalues), signal, 1, w=weighting) | ||
return [np.exp(D[0]), *-D[1:]] | ||
|
||
def ivim_fit(self, bvalues, signal): | ||
""" | ||
Fit an IVIM curve | ||
This fits a bi-exponential curve using linear fitting only | ||
Parameters | ||
---------- | ||
bvalues : list or array of float | ||
The diffusion (b-values) | ||
signal : list or array of float | ||
The acquired signal to fit. It is assumed to be exponential at this point | ||
""" | ||
bvalues = np.asarray(bvalues) | ||
assert bvalues.size > 1, 'Too few b-values' | ||
signal = np.asarray(signal) | ||
assert bvalues.size == signal.size, "Signal and b-values don't have the same number of values" | ||
gd = GenerateData() | ||
lt_cutoff = bvalues <= self.linear_cutoff | ||
gt_cutoff = bvalues >= self.linear_cutoff | ||
linear_signal = np.log(signal) | ||
D = self.linear_fit(bvalues[gt_cutoff], linear_signal[gt_cutoff]) | ||
|
||
if lt_cutoff.sum() > 0: | ||
signal_Dp = linear_signal[lt_cutoff] - gd.linear_signal(D[1], bvalues[lt_cutoff], np.log(D[0])) | ||
|
||
Dp_prime = self.linear_fit(bvalues[lt_cutoff], np.log(signal_Dp)) | ||
|
||
if np.any(np.asarray(Dp_prime) < 0) or not np.all(np.isfinite(Dp_prime)): | ||
print('Perfusion fit failed') | ||
Dp_prime = [0, 0] | ||
f = signal[0] - D[0] | ||
else: | ||
print("This doesn't seem to be an IVIM set of b-values") | ||
f = 1 | ||
Dp_prime = [0, 0] | ||
D = D[1] | ||
Dp = D + Dp_prime[1] | ||
if np.allclose(f, 0): | ||
Dp = 0 | ||
elif np.allclose(f, 1): | ||
D = 0 | ||
return [f, D, Dp] |
Empty file.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,47 @@ | ||
import numpy as np | ||
import numpy.testing as npt | ||
import pytest | ||
import torch | ||
|
||
from utils.data_simulation.GenerateData import GenerateData | ||
from src.original.ETP_SRI.LinearFitting import LinearFit | ||
|
||
|
||
#run using python -m pytest from the root folder | ||
|
||
test_linear_data = [ | ||
pytest.param(0, np.linspace(0, 1000, 11), id='0'), | ||
pytest.param(0.01, np.linspace(0, 1000, 11), id='0.1'), | ||
pytest.param(0.02, np.linspace(0, 1000, 11), id='0.2'), | ||
pytest.param(0.03, np.linspace(0, 1000, 11), id='0.3'), | ||
pytest.param(0.04, np.linspace(0, 1000, 11), id='0.4'), | ||
pytest.param(0.05, np.linspace(0, 1000, 11), id='0.5'), | ||
pytest.param(0.08, np.linspace(0, 1000, 11), id='0.8'), | ||
pytest.param(0.1, np.linspace(0, 1000, 11), id='1'), | ||
] | ||
@pytest.mark.parametrize("D, bvals", test_linear_data) | ||
def test_linear_fit(D, bvals): | ||
gd = GenerateData() | ||
gd_signal = gd.exponential_signal(D, bvals) | ||
print(gd_signal) | ||
fit = LinearFit() | ||
D_fit = fit.linear_fit(bvals, np.log(gd_signal)) | ||
npt.assert_allclose([1, D], D_fit) | ||
|
||
test_ivim_data = [ | ||
pytest.param(0, 0.01, 0.05, np.linspace(0, 1000, 11), id='0'), | ||
pytest.param(0.1, 0.01, 0.05, np.linspace(0, 1000, 11), id='0.1'), | ||
pytest.param(0.2, 0.01, 0.05, np.linspace(0, 1000, 11), id='0.2'), | ||
pytest.param(0.1, 0.05, 0.1, np.linspace(0, 1000, 11), id='0.3'), | ||
pytest.param(0.4, 0.001, 0.05, np.linspace(0, 1000, 11), id='0.4'), | ||
pytest.param(0.5, 0.001, 0.05, np.linspace(0, 1000, 11), id='0.5'), | ||
] | ||
@pytest.mark.parametrize("f, D, Dp, bvals", test_ivim_data) | ||
def test_ivim_fit(f, D, Dp, bvals): | ||
gd = GenerateData() | ||
gd_signal = gd.ivim_signal(D, Dp, f, 1, bvals) | ||
fit = LinearFit() | ||
[f_fit, D_fit, Dp_fit] = fit.ivim_fit(bvals, gd_signal) | ||
npt.assert_allclose([f, D], [f_fit, D_fit], atol=1e-5) | ||
if not np.allclose(f, 0): | ||
npt.assert_allclose(Dp, Dp_fit, rtol=1e-2, atol=1e-3) |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,140 @@ | ||
import numpy as np | ||
|
||
class GenerateData: | ||
""" | ||
Generate exponential and linear data | ||
""" | ||
def __init__(self, operator=None): | ||
""" | ||
Parameters | ||
---------- | ||
operator : numpy or torch | ||
Must provide mathematical operators | ||
""" | ||
if operator is None: | ||
self._op = np | ||
else: | ||
self._op = operator | ||
|
||
def ivim_signal(self, D, Dp, f, S0, bvalues, snr=None): | ||
""" | ||
Generates IVIM (biexponential) signal | ||
Parameters | ||
---------- | ||
D : float | ||
The tissue diffusion value | ||
Dp : float | ||
The pseudo perfusion value | ||
f : float | ||
The fraction of the signal from perfusion | ||
S0 : float | ||
The baseline signal (magnitude at no diffusion) | ||
bvalues : list or array of float | ||
The diffusion (b-values) | ||
""" | ||
signal = self.multiexponential_signal([D, Dp], [1 - f, f], S0, self._op.asarray(bvalues, dtype='float64')) | ||
return self.add_rician_noise(signal, snr) | ||
|
||
def exponential_signal(self, D, bvalues): | ||
""" | ||
Generates exponential signal | ||
Parameters | ||
---------- | ||
D : float | ||
The tissue diffusion value | ||
bvalues : list or array of float | ||
The diffusion (b-values) | ||
""" | ||
assert D >= 0, 'D must be >= 0' | ||
return self._op.exp(-self._op.asarray(bvalues, dtype='float64') * D) | ||
|
||
def multiexponential_signal(self, D, F, S0, bvalues): | ||
""" | ||
Generates multiexponential signal | ||
The combination of exponential signals | ||
Parameters | ||
---------- | ||
D : list or arrray of float | ||
The tissue diffusion value | ||
F : list or array of float | ||
The fraction of the signal from perfusion | ||
S0 : list or array of float | ||
The baseline signal (magnitude at no diffusion) | ||
bvalues : list or array of float | ||
The diffusion (b-values) | ||
""" | ||
assert len(D) == len(F), 'D and F must be the same length' | ||
signal = self._op.zeros_like(bvalues) | ||
for [d, f] in zip(D, F): | ||
signal += f * self.exponential_signal(d, bvalues) | ||
signal *= S0 | ||
return signal | ||
|
||
def add_rician_noise(self, real_signal, snr=None, imag_signal=None): | ||
""" | ||
Adds Rician noise to a real or complex signal | ||
Parameters | ||
---------- | ||
real_signal : list or array of float | ||
The real channel float | ||
snr : float | ||
The signal to noise ratio | ||
imag_signal : list or array of float | ||
The imaginary channel float | ||
""" | ||
if imag_signal is None: | ||
imag_signal = self._op.zeros_like(real_signal) | ||
if snr is None: | ||
noisy_data = self._op.sqrt(self._op.power(real_signal, 2) + self._op.power(imag_signal, 2)) | ||
else: | ||
real_noise = self._op.random.normal(0, 1 / snr, real_signal.shape) | ||
imag_noise = self._op.random.normal(0, 1 / snr, imag_signal.shape) | ||
noisy_data = self._op.sqrt(self._op.power(real_signal + real_noise, 2) + self._op.power(imag_signal + imag_noise, 2)) | ||
return noisy_data | ||
|
||
def linear_signal(self, D, bvalues, offset=0): | ||
""" | ||
Generates linear signal | ||
Parameters | ||
---------- | ||
D : float | ||
The tissue diffusion value | ||
bvalues : list or array of float | ||
The diffusion (b-values) | ||
offset : float | ||
The signal offset | ||
""" | ||
assert D >= 0, 'D must be >= 0' | ||
data = -D * np.asarray(bvalues) | ||
return data + offset | ||
|
||
def multilinear_signal(self, D, F, S0, bvalues, offset=0): | ||
""" | ||
Generates multilinear signal | ||
The combination of multiple linear signals | ||
Parameters | ||
---------- | ||
D : list or arrray of float | ||
The tissue diffusion value | ||
F : list or array of float | ||
The fraction of the signal from perfusion | ||
S0 : list or array of float | ||
The baseline signal (magnitude at no diffusion) | ||
bvalues : list or array of float | ||
The diffusion (b-values) | ||
offset : float | ||
The signal offset | ||
""" | ||
assert len(D) == len(F), 'D and F must be the same length' | ||
signal = self._op.zeros_like(bvalues) | ||
for [d, f] in zip(D, F): | ||
signal += f * self.linear_signal(d, bvalues) | ||
signal *= S0 | ||
signal += offset | ||
return signal |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters