def deconvolve_image(imagefile, kernel, vb=False):
##------------------------------------------------------------
## Read in image
## Determine image file type and get pixels
try:
imgext = os.path.splitext(imagefile)[1]
if imgext==".fits":
imgarr = fits_pix(imagefile)
elif imgext==".png":
assert False, "Cannot handle PNG format."
## For some reason the image is flipped at this point, so un-flip
imgarr = imgarr[::-1,:]
## Or, if the imagefile is already an array
except AttributeError:
imgarr = imagefile
##------------------------------------------------------------
## Read in kernel
## Distinguish between array-kernel and file-kernel
if type(kernel) is str:
## Ensure the right kernel file has been selected
if "PSFtoGauss" in kernel:
kernel = numpy.loadtxt(kernel)
else:
print "DeconvolveToTargetPSF.py: deconvolve_image: wrong kernel file. Abort."
return
elif type(kernel) is numpy.array:
pass
## Kernel dimensions
kernel_h,kernel_w = kernel.shape
#scipy.misc.imsave("../doc/Images/kernel.png", kernel) #####
#scipy.misc.imsave("../doc/Images/image.png",imgarr) #####
##------------------------------------------------------------
## Have kernel and original image; now we need to solve the matrix equation
## Kx = b, where K is kernel, x is target image, and b is our observed image.
## FIRST, dimensions of data image should be greater than those of scene
## to ensure a stable solution.
## Pad so that the scene has same dimensions of original data.
refimg_dim = imgarr.shape
refimg_size = imgarr.size
obsimg_dim = numpy.array(imgarr.shape) + numpy.array(kernel.shape) - 1
obsimg_size = obsimg_dim[0]*obsimg_dim[1]
## SECOND, construct matrix K from kernel array.
## kernmat should be obsimg_size by refimg_size
## What is first row of kernmat?
krow = numpy.zeros(refimg_size)
for i in range(kernel_h):
j = i*refimg_dim[0] ## Stride number
krow[j:j+kernel_w] = kernel[i,:]
## First column of kernmat (declare too large)
kcol = numpy.zeros(obsimg_size); kcol[0]=krow[0]
## Create dense Toeplitz matrix (not square)
## This contains all the relevant rows; we'll chop it up later
kernmat = scipy.linalg.toeplitz(kcol,krow)
## Some rows of the kernel matrix will be no good -- they represent pixel where the convolution
## oversteps the image border
## There must be a better way of doing this
badrow = [numpy.arange(i*refimg_dim[0]-kernel_w+2, i*refimg_dim[0]+1) for i in range(1,refimg_dim[1])]
## Delete spurious rows
kernmat = numpy.delete(kernmat, badrow, axis=0)
## Also delete end rows from declaring kcol too large
##convimgsiz is how big the kernel matrix should be if we are true to convolution
convimgsiz = (refimg_dim[0]-kernel.shape[0]+1)*(refimg_dim[1]-kernel.shape[1]+1)
kernmat = kernmat[:convimgsiz,:]
#scipy.misc.imsave("../doc/Images/kernmat.png", kernmat) #####
## Now we need to pad out the kernel matrix to reflect padding of the data image
## do inner bits
insertionrow = numpy.arange(refimg_dim[0]-kernel.shape[0]+2, convimgsiz, refimg_dim[0]-kernel.shape[0]+1).repeat(2*(obsimg_dim[0]-imgarr.shape[0]))
kernmat = numpy.insert(kernmat, insertionrow, numpy.zeros(refimg_size), axis=0)
## do ends
thickpad = numpy.zeros([(obsimg_dim[0]+1)*(obsimg_dim[0]-imgarr.shape[0]),refimg_size])
kernmat = numpy.append(kernmat, thickpad, axis=0)
kernmat = numpy.append(thickpad, kernmat, axis=0)
#scipy.misc.imsave("../doc/Images/kernmat_pad.png", kernmat) #####
## Don't need these any more
kcol=None; krow=None; badrow=None; insertionrow=None; thickpad=None
scipy.misc.imsave("kernmat.png",kernmat)
## Turn dense kernmat into a sparse matrix
#kernmat = scipy.sparse.dia_matrix(kernmat)
## THIRD, construct vector b from observed image
## This is padded with zeros so to make the matrix equation well-defined
imgvec = pad(obsimg_dim, imgarr).flatten()
#scipy.misc.imsave("../doc/Images/image_pad.png", imgvec.reshape(obsimg_dim)) #####
## FOURTH, solve the equation Kx = b
## The system of equations is UNDERdetermined
t0=time.time()
## Decide whether to use initial guess or not
if False:
print "Using intital guess."
## Make initial guess; must be conformable
refimg0 = shave(refimg_dim, imgarr).flatten()
## Solve matrix equation K*(dx)=res
residual = imgvec-numpy.dot(kernmat,refimg0)
#correction,istop,itn = scipy.sparse.linalg.lsqr(kernmat, residuals, calc_var=False)[:3]
correction,resi = numpy.linalg.lstsq(kernmat, residual)[:2]
## Add initial solution to correction
refimgvec = refimg0 + correction
## Tidy up
correction = None; residual = None; refimg0 = None
## Or just straight solve
else:
## Account for noise
#####
## Sparse method or regular
#refimgvec,istop,itn,r1norm,r2norm = scipy.sparse.linalg.lsqr(kernmat, imgvec, calc_var=False)[:5]
refimgvec,resi = numpy.linalg.lstsq(kernmat, imgvec)[:2]
if vb:
print "image_deconvolve: least-squares converged to reference image in",\
round(time.time()-t0,2),"seconds."
##------------------------------------------------------------
## Check: reverse procedure
check = False
if check is True:
resi = (numpy.dot(kernmat,refimgvec)-imgvec).reshape(obsimg_dim)
scipy.misc.imsave("check_resi.png", resi)
scipy.misc.imsave("check_recon.png", numpy.dot(kernmat,refimgvec).reshape(obsimg_dim))
##------------------------------------------------------------
## Reshape into an image
refimg = refimgvec.reshape(refimg_dim)
##------------------------------------------------------------
## Outfile name
try:
imagedir,imagename = os.path.split(imagefile)
info = imagename[imagename.find("CFHT"):imagename.find("sci")+3]
outfile = imagedir+"/gDeconvolved_"+info
header = fits_hdr(imagefile)
except (TypeError, AttributeError):
## If the input was in array format
outfile = "deconvolved"
header = None
##------------------------------------------------------------
## Rescale (linear stretch)
if True:
## Scaling parameters
vmin,vmax = stretch_params(refimg)
## Stretch
refimg = linear_rescale(refimg, vmin, vmax)
## Modify filename
outfile = outfile+"_rescaled"
## Delete pre-existing images
if os.path.isfile(outfile+".fits"): os.remove(outfile+".fits")
if os.path.isfile(outfile+".png"): os.remove(outfile+".png")
## Save image as FITS and as PNG
#makeFITS(outfile+".fits", refimg, header)
#scipy.misc.imsave(outfile+".png", refimg)
if vb: print "DeconvolveToTargetPSF.py: deconvolve_image: image saved to",outfile+".fits"
return refimg
def deconvolve_image(imagefile, kernel, vb=False):
##------------------------------------------------------------
## Read in image
## Determine image file type and get pixels
imgext = os.path.splitext(imagefile)[1]
if imgext==".fits": imgarr = fits_pix(imagefile)
elif imgext==".png": imgarr = png_pix(imagefile) ## Doesn't work
## For some reason the image is flipped at this point, so un-flip
imgarr = imgarr[::-1,:]
## Filter out noise
imgarr[imgarr<cutoff] = 0.0
##------------------------------------------------------------
## Read in kernel
## Distinguish between array-kernel and file-kernel
if type(kernel) is str:
## Ensure the right kernel file has been selected
if "PSFtoGauss" in kernel:
kernel = numpy.loadtxt(kernel)
else:
print "DeconvolveToTargetPSF.py: deconvolve_image: wrong kernel file. Abort."
return
elif type(kernel) is numpy.array:
pass
## Kernel dimensions
kernel_h,kernel_w = kernel.shape
# Should also check match with imagefile #
##------------------------------------------------------------
## Compute linalg objects from images
## Honest dimensions for scene
scene_dim = numpy.array(imgarr.shape)-numpy.array(kernel.shape)+1
scene_siz = scene_dim[0]*scene_dim[1]
##------------------------------------------------------------
convmeth = "scipy"
## Manual convolution
if convmeth=="manual":
## 1D array for SCENE (convolved with Gaussian)
g_sc = numpy.empty(imgarr.size)#scene_siz
## 1D array for IMAGE
stride = imgarr.shape[0]
imgarr = imgarr.flatten()
##------------------------------------------------------------
## Manual matrix product
## Initialise kernel "vector"
len_krn_lin = (stride)*(kernel_h-1)+kernel_w ## Still keeps a lot of zeros
krn_lin = numpy.zeros(len_krn_lin)
## Loop over slices in the kernel image
for j in range (kernel_h):
startcol = j*stride
krn_lin[startcol:startcol+kernel_w] = kernel[j,:]
t0 = time.time()
## Perform linalg product
## i labels the scene pixel and the slice in the original
for i in range (scene_siz):
imageslice = imgarr[i:i+len_krn_lin]
g_sc[i] = numpy.dot(krn_lin,imageslice)
if vb: print "DeconvolveToTargetPSF.py: deconvolve_image: vector multiplication took",\
round(time.time()-t0,2),"seconds."
## Delete spurious elements (from overlapping)
i=len(g_sc)
while i>=0:
if i%stride+kernel_w > stride:
g_sc = numpy.delete(g_sc,i)
i-=1
## Delete spurious elements from declaring it too big
g_sc = numpy.delete(g_sc,slice(scene_siz-len(g_sc)-1,-1))
if scene_siz-len(g_sc): print "LINE #"+str(lineno())+": size discrepancy"
##------------------------------------------------------------
elif convmeth=="scipy":
t0=time.time()
## Do convolution using scipy
imgarr = numpy.array(imgarr, dtype="float64")
g_sc = convolve(imgarr, kernel, mode="valid")
if vb: print "DeconvolveToTargetPSF.py: deconvolve_image: SciPy convolution took",\
round(time.time()-t0,2),"seconds."
else:
print "LINE #"+str(lineno())+": convmeth error, abort."
return
##------------------------------------------------------------
## Reshape
if g_sc.shape[0]!=scene_dim[0] or g_sc.shape[1]!=scene_dim[1]:
if vb: print "DeconvolveToTargetPSF.py: deconvolve_image: reshaping."
try:
g_sc = g_sc.reshape(scene_dim)
except ValueError:
print "DeconvolveToTargetPSF.py: deconvolve_image: output has wrong shape. Investigate."
##------------------------------------------------------------
## Filter out (computer) noise
g_sc[g_sc<cutoff] = 0.0
## Outfile name
imagedir,imagename = os.path.split(imagefile)
info = imagename[imagename.find("CFHT"):imagename.find("sci")+3]
outfile = imagedir+"/gDeconvolved_"+info
## Rescale (linear stretch)
if 1:
## Scaling parameters
vmin,vmax = stretch_params(g_sc)
## Stretch
g_sc = linear_rescale(g_sc, vmin, vmax)
## Modify filename
outfile = outfile+"_rescaled"
## Delete pre-existing images
if os.path.isfile(outfile+".fits"): os.remove(outfile+".fits")
if os.path.isfile(outfile+".png"): os.remove(outfile+".png")
## Save image as FITS and as PNG
makeFITS(outfile+".fits", g_sc)
scipy.misc.imsave(outfile+".png", g_sc)
if vb: print "DeconvolveToTargetPSF.py: deconvolve_image: image saved to",outfile+".fits"
return None
def deconvolve_image(imagefile, kernel, vb=False):
##------------------------------------------------------------
## Read in image
## Determine image file type and get pixels
try:
imgext = os.path.splitext(imagefile)[1]
if imgext == ".fits":
imgarr = fits_pix(imagefile)
elif imgext == ".png":
assert False, "Cannot handle PNG format."
## For some reason the image is flipped at this point, so un-flip
imgarr = imgarr[::-1, :]
## Or, if the imagefile is already an array
except AttributeError:
imgarr = imagefile
##------------------------------------------------------------
## Read in kernel
## Distinguish between array-kernel and file-kernel
if type(kernel) is str:
## Ensure the right kernel file has been selected
if "PSFtoGauss" in kernel:
kernel = numpy.loadtxt(kernel)
else:
print "DeconvolveToTargetPSF.py: deconvolve_image: wrong kernel file. Abort."
return
elif type(kernel) is numpy.array:
pass
## Kernel dimensions
kernel_h, kernel_w = kernel.shape
#scipy.misc.imsave("../doc/Images/kernel.png", kernel) #####
#scipy.misc.imsave("../doc/Images/image.png",imgarr) #####
##------------------------------------------------------------
## Have kernel and original image; now we need to solve the matrix equation
## Kx = b, where K is kernel, x is target image, and b is our observed image.
## FIRST, dimensions of data image should be greater than those of scene
## to ensure a stable solution.
## Pad so that the scene has same dimensions of original data.
refimg_dim = imgarr.shape
refimg_size = imgarr.size
obsimg_dim = numpy.array(imgarr.shape) + numpy.array(kernel.shape) - 1
obsimg_size = obsimg_dim[0] * obsimg_dim[1]
## SECOND, construct matrix K from kernel array.
## kernmat should be obsimg_size by refimg_size
## What is first row of kernmat?
krow = numpy.zeros(refimg_size)
for i in range(kernel_h):
j = i * refimg_dim[0] ## Stride number
krow[j:j + kernel_w] = kernel[i, :]
## First column of kernmat (declare too large)
kcol = numpy.zeros(obsimg_size)
kcol[0] = krow[0]
## Create dense Toeplitz matrix (not square)
## This contains all the relevant rows; we'll chop it up later
kernmat = scipy.linalg.toeplitz(kcol, krow)
## Some rows of the kernel matrix will be no good -- they represent pixel where the convolution
## oversteps the image border
## There must be a better way of doing this
badrow = [
numpy.arange(i * refimg_dim[0] - kernel_w + 2, i * refimg_dim[0] + 1)
for i in range(1, refimg_dim[1])
]
## Delete spurious rows
kernmat = numpy.delete(kernmat, badrow, axis=0)
## Also delete end rows from declaring kcol too large
##convimgsiz is how big the kernel matrix should be if we are true to convolution
convimgsiz = (refimg_dim[0] - kernel.shape[0] + 1) * (refimg_dim[1] -
kernel.shape[1] + 1)
kernmat = kernmat[:convimgsiz, :]
#scipy.misc.imsave("../doc/Images/kernmat.png", kernmat) #####
## Now we need to pad out the kernel matrix to reflect padding of the data image
## do inner bits
insertionrow = numpy.arange(refimg_dim[0] - kernel.shape[0] + 2,
convimgsiz,
refimg_dim[0] - kernel.shape[0] + 1).repeat(
2 * (obsimg_dim[0] - imgarr.shape[0]))
kernmat = numpy.insert(kernmat,
insertionrow,
numpy.zeros(refimg_size),
axis=0)
## do ends
thickpad = numpy.zeros([
(obsimg_dim[0] + 1) * (obsimg_dim[0] - imgarr.shape[0]), refimg_size
])
kernmat = numpy.append(kernmat, thickpad, axis=0)
kernmat = numpy.append(thickpad, kernmat, axis=0)
#scipy.misc.imsave("../doc/Images/kernmat_pad.png", kernmat) #####
## Don't need these any more
kcol = None
krow = None
badrow = None
insertionrow = None
thickpad = None
scipy.misc.imsave("kernmat.png", kernmat)
## Turn dense kernmat into a sparse matrix
#kernmat = scipy.sparse.dia_matrix(kernmat)
## THIRD, construct vector b from observed image
## This is padded with zeros so to make the matrix equation well-defined
imgvec = pad(obsimg_dim, imgarr).flatten()
#scipy.misc.imsave("../doc/Images/image_pad.png", imgvec.reshape(obsimg_dim)) #####
## FOURTH, solve the equation Kx = b
## The system of equations is UNDERdetermined
t0 = time.time()
## Decide whether to use initial guess or not
if False:
print "Using intital guess."
## Make initial guess; must be conformable
refimg0 = shave(refimg_dim, imgarr).flatten()
## Solve matrix equation K*(dx)=res
residual = imgvec - numpy.dot(kernmat, refimg0)
#correction,istop,itn = scipy.sparse.linalg.lsqr(kernmat, residuals, calc_var=False)[:3]
correction, resi = numpy.linalg.lstsq(kernmat, residual)[:2]
## Add initial solution to correction
refimgvec = refimg0 + correction
## Tidy up
correction = None
residual = None
refimg0 = None
## Or just straight solve
else:
## Account for noise
#####
## Sparse method or regular
#refimgvec,istop,itn,r1norm,r2norm = scipy.sparse.linalg.lsqr(kernmat, imgvec, calc_var=False)[:5]
refimgvec, resi = numpy.linalg.lstsq(kernmat, imgvec)[:2]
if vb:
print "image_deconvolve: least-squares converged to reference image in",\
round(time.time()-t0,2),"seconds."
##------------------------------------------------------------
## Check: reverse procedure
check = False
if check is True:
resi = (numpy.dot(kernmat, refimgvec) - imgvec).reshape(obsimg_dim)
scipy.misc.imsave("check_resi.png", resi)
scipy.misc.imsave("check_recon.png",
numpy.dot(kernmat, refimgvec).reshape(obsimg_dim))
##------------------------------------------------------------
## Reshape into an image
refimg = refimgvec.reshape(refimg_dim)
##------------------------------------------------------------
## Outfile name
try:
imagedir, imagename = os.path.split(imagefile)
info = imagename[imagename.find("CFHT"):imagename.find("sci") + 3]
outfile = imagedir + "/gDeconvolved_" + info
header = fits_hdr(imagefile)
except (TypeError, AttributeError):
## If the input was in array format
outfile = "deconvolved"
header = None
##------------------------------------------------------------
## Rescale (linear stretch)
if True:
## Scaling parameters
vmin, vmax = stretch_params(refimg)
## Stretch
refimg = linear_rescale(refimg, vmin, vmax)
## Modify filename
outfile = outfile + "_rescaled"
## Delete pre-existing images
if os.path.isfile(outfile + ".fits"): os.remove(outfile + ".fits")
if os.path.isfile(outfile + ".png"): os.remove(outfile + ".png")
## Save image as FITS and as PNG
#makeFITS(outfile+".fits", refimg, header)
#scipy.misc.imsave(outfile+".png", refimg)
if vb:
print "DeconvolveToTargetPSF.py: deconvolve_image: image saved to", outfile + ".fits"
return refimg