def compute_Ax1(I, W0, th, h_2d, scale_factor):
KI = frame_utility.cconv2d(h_2d, I)
SKI = frame_utility.down_sample(KI, scale_factor)
W0SKI = W0 * SKI
StW0SKI = frame_utility.up_sample(W0SKI, scale_factor)
KtStW0SKI = frame_utility.cconv2dt(h_2d, StW0SKI)
AI1 = th * KtStW0SKI
return AI1
def compute_Ax1_k(K, I, Wk, th, scale_factor):
AK = frame_utility.cconv2d(K, I)
SAK = frame_utility.down_sample(AK, scale_factor)
WkSAK = Wk * SAK
StWkSAK = frame_utility.up_sample(WkSAK, scale_factor)
AtStWkSAK = frame_utility.cconv2dt(I, StWkSAK)
AK1 = th * AtStWkSAK
return AK1
def compute_Ax3(FI, Wi, th, h_2d, scale_factor, ut, vt):
KFI = frame_utility.cconv2d(h_2d, FI)
SKFI = frame_utility.down_sample(KFI, scale_factor)
WSKFI = Wi * SKFI
StWSKFI = frame_utility.up_sample(WSKFI, scale_factor)
KtStWSKFI = frame_utility.cconv2dt(h_2d, StWSKFI)
FtKtStWSKFI = frame_utility.warped_img(KtStWSKFI, ut, vt)
AI3 = th * FtKtStWSKFI
return AI3
ut[j + i] = -u[j + i]
vt[j + i] = -v[j + i]
FI[j + i] = frame_utility.warped_img(
current_I, u[j + i], v[j + i])
# estimate noise
nq = low_res_width * low_res_height
print('noise estimation ...')
if k == 0:
for i in range(-n_back, n_for + 1):
theta[j + i] = max(1, max(n_back, n_for)) / (abs(i) + 1)
else:
for i in range(-n_back, n_for + 1):
if i == 0:
KI = frame_utility.cconv2d(h_2d, current_I)
SKI = frame_utility.down_sample(KI, scale_factor)
x_tmp = np.sum(np.abs(current_low[j + i] - SKI)) / nq
theta[j + i] = (alpha + nq - 1) / (beta + nq * x_tmp)
else:
KFI = frame_utility.cconv2d(h_2d, FI[j + i])
SKFI = frame_utility.down_sample(KFI, scale_factor)
x_tmp = np.sum(np.abs(current_low[j + i] - SKFI)) / nq
theta[j + i] = (alpha + nq - 1) / (beta + nq * x_tmp)
# estimate high resolution image
print('high resolution image estimation .. ')
for m in range(max_iteration):
print('%d th high resolution estimation IRLS iteration' % m)
I_old_in = current_I
W0 = kernel_utility.compute_W0(current_I, J0, h_2d,
scale_factor)
def compute_Wk(K, I, J0, scale_factor):
AK = frame_utility.cconv2d(K, I)
SAK = frame_utility.down_sample(AK, scale_factor)
Wk = weight_matrix(SAK - J0)
return Wk
def compute_Wi(FI, J, h_2d, scale_factor):
KFI = frame_utility.cconv2d(h_2d, FI)
SKFI = frame_utility.down_sample(KFI, scale_factor)
Wi = weight_matrix(SKFI - J)
return Wi
def compute_W0(I, J0, h_2d, scale_factor):
KI = frame_utility.cconv2d(h_2d, I)
SKI = frame_utility.down_sample(KI, scale_factor)
W0 = weight_matrix(SKI - J0)
return W0