def _reconstruct(self, observation, out):
observation = self.observation_space.element(observation)
out[:] = self.x0
gradient = Gradient(self.op.domain)
L = [self.op, gradient]
f = ZeroFunctional(self.op.domain)
l2_norm = 0.5 * L2NormSquared(self.op.range).translated(observation)
l12_norm = self.lam * GroupL1Norm(gradient.range)
g = [l2_norm, l12_norm]
op_norm = power_method_opnorm(self.op, maxiter=20)
gradient_norm = power_method_opnorm(gradient, maxiter=20)
sigma_ray_trafo = 45.0 / op_norm**2
sigma_gradient = 45.0 / gradient_norm**2
sigma = [sigma_ray_trafo, sigma_gradient]
h = ZeroFunctional(self.op.domain)
forward_backward_pd(out,
f,
g,
L,
h,
self.tau,
sigma,
self.niter,
callback=self.callback)
return out
def _reconstruct(self, observation, out):
observation = self.observation_space.element(observation)
out_ = out
if out not in self.reco_space:
out_ = self.reco_space.zero()
out_[:] = self.x0
gradient = Gradient(self.op.domain)
L = BroadcastOperator(self.op, gradient)
f = ZeroFunctional(self.op.domain)
l2_norm = L2NormSquared(self.op.range).translated(observation)
l1_norm = self.lam * L1Norm(gradient.range)
g = SeparableSum(l2_norm, l1_norm)
op_norm = 1.1 * power_method_opnorm(L, maxiter=20)
sigma = self.tau * op_norm**2
admm.admm_linearized(out_,
f,
g,
L,
self.tau,
sigma,
self.niter,
callback=self.callback)
if out not in self.reco_space:
out[:] = out_
return out
def _reconstruct(self, observation, out):
# The proximal_gradient and accelerated_proximal_gradient methods
# from ODL have as input the function, which needs to be minimized
# (and not the forward operator itself). Therefore, we calculate the
# discrepancy ||Ax-b||_2^2. Note that the terms `f` and `g` are
# switched in odl compared to the usage in the FISTA paper
# (https://epubs.siam.org/doi/abs/10.1137/080716542).
observation = self.observation_space.element(observation)
out[:] = self.x0
l2_norm_sq_trans = L2NormSquared(self.op.range).translated(observation)
discrepancy = l2_norm_sq_trans * self.op
if not self.accelerated:
proximal_gradient_solvers.proximal_gradient(out,
self.reg,
discrepancy,
self.gamma,
self.niter,
callback=self.callback,
lam=self.lam)
else:
proximal_gradient_solvers.accelerated_proximal_gradient(
out,
self.reg,
discrepancy,
self.gamma,
self.niter,
callback=self.callback,
lam=self.lam)
return out
def __call__(self, x):
ret = 0
xim = x[:self.N]
for i in range(self.N):
if self.alpha[i] != 0:
xi = xim[i]
res = self.residual(xi, i)
ret += 0.5 * self.alpha[i] * L2NormSquared(res.space)(res)
return ret
def __call__(self, x): # x is space time element im x vf
ret = 0.
xim = x[:self.N]
xvf = x[self.N:]
for i in range(self.N - 1):
ximi = xim[i]
ximii = xim[i + 1]
xvfi = xvf[i]
res = self.residual(ximii, ximi, xvfi)
ret += 0.5 * L2NormSquared(res.space)(res)
return self.alpha * ret
def _reconstruct(self, observation, out):
observation = self.observation_space.element(observation)
out[:] = self.x0
l2_norm = L2NormSquared(self.op.range)
discrepancy = l2_norm * (self.op - observation)
gradient = Gradient(self.op.domain)
l1_norm = GroupL1Norm(gradient.range)
smoothed_l1 = MoreauEnvelope(l1_norm, sigma=0.03)
regularizer = smoothed_l1 * gradient
f = discrepancy + self.lam * regularizer
opnorm = power_method_opnorm(self.op)
hessinv_estimate = ScalingOperator(self.op.domain, 1 / opnorm**2)
newton.bfgs_method(f,
out,
maxiter=self.niter,
hessinv_estimate=hessinv_estimate,
callback=self.callback)
return out
def _reconstruct(self, observation, out):
observation = self.observation_space.element(observation)
out[:] = self.x0
gradient = Gradient(self.op.domain)
L = BroadcastOperator(self.op, gradient)
f = ZeroFunctional(self.op.domain)
l2_norm = L2NormSquared(self.op.range).translated(observation)
l1_norm = self.lam * L1Norm(gradient.range)
g = [l2_norm, l1_norm]
tau, sigma = douglas_rachford.douglas_rachford_pd_stepsize(L)
douglas_rachford.douglas_rachford_pd(out,
f,
g,
L,
self.niter,
tau,
sigma,
callback=self.callback)
return out
def _reconstruct(self, observation, out):
observation = self.observation_space.element(observation)
out[:] = self.x0
gradient = Gradient(self.op.domain)
L = BroadcastOperator(self.op, gradient)
f = ZeroFunctional(self.op.domain)
l2_norm = L2NormSquared(self.op.range).translated(observation)
l1_norm = self.lam * L1Norm(gradient.range)
g = SeparableSum(l2_norm, l1_norm)
tau, sigma = primal_dual_hybrid_gradient.pdhg_stepsize(L)
primal_dual_hybrid_gradient.pdhg(out,
f,
g,
L,
self.niter,
tau,
sigma,
callback=self.callback)
return out
def __init__(self, space, data, forward=None):
self.space = space
self.image_space = self.space[0]
self.affine_space = self.space[1]
self.rest_space = self.space[2]
self.deformation_space = ProductSpace(self.affine_space,
self.rest_space)
self.data = data
if forward is None:
self.forward = IdentityOperator(self.image_space)
else:
self.forward = forward
self.datafit = 0.5 * L2NormSquared(self.image_space).translated(
self.data)
self.embedding_affine_rest = ops.Embedding_Affine_Rest(
self.deformation_space, self.image_space.tangent_bundle)
self.embedding_affine = ops.Embedding_Affine(
self.affine_space, self.image_space.tangent_bundle)
super(DataFitL2DispAffRest, self).__init__(space=space,
linear=False,
grad_lipschitz=np.nan)
def __init__(self, space, data, forward=None):
self.space = space
self.image_space = self.space[0]
self.affine_space = self.space[1]
self.data = data
if forward is None:
self.forward = IdentityOperator(self.image_space)
else:
self.forward = forward
self.datafit = 0.5 * L2NormSquared(data.space).translated(self.data)
if isinstance(self.image_space, odl.ProductSpace):
tangent_bundle = self.image_space[0].tangent_bundle
else:
tangent_bundle = self.image_space.tangent_bundle
self.embedding = ops.Embedding_Affine(self.affine_space,
tangent_bundle)
super(DataFitL2Disp, self).__init__(space=space,
linear=False,
grad_lipschitz=np.nan)
def minimization_alpha(dataset, reg, alpha, energy, nangles):
alg_name = 'fbs'
sinfo_type = 'tv' # can be choose to be 'tv' or 'fbp'
alg = '{}{}'.format(alg_name, reg)
folder_data = './data/{}'.format(dataset)
variables = {}
with open('{}/parameters.txt'.format(folder_data)) as data_file:
for line in data_file:
name, value = line.split(" ")
variables[name] = float(value)
dom_width = variables["dom_width"]
ndet = int(variables['ndet'])
# Data and reconstruction size
n = 512
# Change these values if a different side information TV-reg is used
if dataset == 'xcat':
if sinfo_type == 'fbp':
sinfo_name = 'fbp'
elif sinfo_type == 'tv':
sinfo_name = '0_1'
elif dataset == 'bird':
sinfo_name = '0_03'
# Folder to save
alpha_folder = './results/{}/{}/{}_angles/' \
'{}_alphas_{}'.format(dataset, alg_name, nangles, energy,
reg)
st = 1
sett = {
'fbsTV': {
'outer_iter': 500,
'inner_iter': 200,
'tol': 1e-5
},
'fbsdTV': {
'outer_iter': 500,
'inner_iter': 200,
'tol': 1e-5
}
}
if sinfo_name == 'fbp':
alpha_folder = '{}/fbp_side_info'.format(alpha_folder)
if not os.path.exists(alpha_folder):
os.makedirs(alpha_folder)
niter, iter_save_x, iter_save_meas, iter_plot = {}, {}, {}, {}
sett_keys = sett.keys()
for a in sett_keys:
niter[a] = sett[a]['outer_iter'] + 1
iter_save_x[a] = range(0, niter[a], 1)
iter_save_meas[a] = range(0, niter[a], 1)
iter_plot[a] = range(0, niter[a], 5)
# %%
gt_fbp = {}
gt_tv = {}
if dataset == 'bird':
# FBP
gt_fbp[energy] = np.load('{}/{}_{}x{}_FBP_'
'reference.npy'.format(
folder_data, energy, n, n))
# TV reconstruction
ref_alphas = {'E0': 5e-3, 'E1': 2e-3, 'E2': 2e-3}
ref_alpha = ref_alphas[energy]
name = '{}_{}x{}_reference_reconstruction'.format(energy, n, n)
name = name + '_alpha_' + str(ref_alpha).replace('.', '_')
ref_dir = '{}/{}.npy'.format(folder_data, name)
gt_tv[energy] = np.load(ref_dir)[0]
elif dataset == 'xcat':
# FBP
gt_fbp[energy] = np.load('{}/{}_{}x{}_FBP_'
'reference.npy'.format(
folder_data, energy, n, n))
gt_tv[energy] = gt_fbp[energy]
U = odl.uniform_discr([-dom_width * 0.5, -dom_width * 0.5],
[dom_width * 0.5, dom_width * 0.5], (n, n))
# %%
# dTV parameters and side information
eta = 1e-2
eta_str = '{0:.1e}'.format(eta)
eta_str = eta_str.replace('-', '_')
if sinfo_name == 'fbp':
sinfo = np.load('{}/sinfo_fbp_{}x{}'
'.npy'.format(folder_data, nangles, ndet))
else:
sinfo = np.load('{}/sinfo_TV_reconstruction_{}_d{}x{}_m{}'
'.npy'.format(folder_data, sinfo_name, nangles, ndet,
n))
D = misc.dTV(U, sinfo, eta)
# Data
data = {}
name_data = np.load('{}/sinograms_{}x{}.npy'.format(
folder_data, nangles, ndet))
sinogram = name_data.item()
# Operators and optimization parameters
g = {}
Lipschitz_cte = {}
R = misc.forward_operator(dataset, 'sample', nangles)
data[energy] = R.range.element(sinogram[energy])
data_space = data[energy].space
data_fit = 0.5 * L2NormSquared(data_space).translated(data[energy])
g[energy] = data_fit * R
Lipschitz_cte[energy] = R.norm(estimate=True)**2
sigma_fbs = 1 / Lipschitz_cte[energy]
# Run algorithm for different values of alpha
alpha_str = '{0:.1e}'.format(alpha)
alpha_str = alpha_str.replace('.', '_')
alpha_name = 'alpha_{}'.format(alpha_str)
name = '{}/{}.npy'.format(alpha_folder, alpha_name)
# if os.path.isfile(name):
# os.system('say "Esta configuracion ya fue ejecutada"')
# return
print('\n Solving reconstruction using alpha = {}\n'.format(alpha))
fit_value = g[energy]
prox_options = {}
prox_options['niter'] = sett[alg]['inner_iter']
prox_options['tol'] = sett[alg]['tol']
prox_options['name'] = 'FGP'
prox_options['warmstart'] = True
prox_options['p'] = None
alpha = alpha
strong_convexity = 0
if alg == 'fbsdTV':
grad = D
elif alg == 'fbsTV':
grad = None
Ru = TVnn(U,
alpha=alpha,
prox_options=prox_options,
grad=grad,
strong_convexity=strong_convexity)
function_value = g[energy] + Ru
def ssim_val(x, x_truth=gt_tv[energy]):
return ssim(x, x_truth)
ssfolder = '{}/{}'.format(alpha_folder, alpha_name)
if not os.path.exists(ssfolder):
os.makedirs(ssfolder)
cb1 = odl.solvers.CallbackPrintIteration
cb2 = odl.solvers.CallbackPrintTiming
cb3 = odl.solvers.CallbackPrint
cb3b = odl.solvers.CallbackPrint
# cb4 = misc.CallbackStoreA(alg=alg, iter_save_x=iter_save_x[alg],
# iter_save_meas=iter_save_meas[alg],
# iter_plot=None,
# x_truth_tv=gt_tv[energy],
# x_truth_fbp=gt_fbp[energy], ssfolder=ssfolder,
# vmax=None, cmap=None)
cb = (cb1(fmt='iter:{:4d}', step=st, end=', ')
& cb2(fmt='time: {:5.2f} s', cumulative=True, step=st, end=', ')
& cb3(function_value, fmt='f(x)={0:.4g}', step=st, end=', ')
& cb3(fit_value, fmt='data_fit(x)={0:.4g}', step=st, end=', ')
& cb3b(ssim_val, fmt='ssim={0:.4g}', step=st))
x = U.one()
misc.fbs(U,
g[energy],
Ru,
sigma_fbs,
g_grad=None,
x=x,
niter=niter[alg],
callback=cb)
solution = x
name = '{}/{}.npy'.format(alpha_folder, alpha_name)
np.save(name, solution)