def download_tgss_image(url):
"""Download an image for TGSS.
Parameters
----------
url:
url of the image.
Returns
-------
file_url:
Url of the newly downloaded file.
"""
# parsing ra and dec from the url
query = urlparse(url).query
h_pos = parse_qs(query)['hPOS'][0]
ra, dec = h_pos.split(',')
# name of the temporary tar file to be saved locally
local_file_name = '{}_{}.tar'.format(ra, dec)
# getting the tar file downloaded
request = requests.get(url, stream=True)
with open(local_file_name, 'wb') as f:
for chunk in request.iter_content(chunk_size=1024):
if chunk:
f.write(chunk)
f.flush()
tar = tarfile.open(local_file_name)
members = tar.getmembers()
# temp folder for the fits file
temp_folder = local_file_name.replace('.tar', '')
tar.extract(member=members[0], path=temp_folder)
# removing the temporary file
os.remove(local_file_name)
fits_image = temp_folder + '/' + members[0].name
hdu_list = fits.open(fits_image)
stretch = vis.AsinhStretch(0.01) + vis.MinMaxInterval()
file_url = settings.MEDIA_ROOT + 'database_images/' + temp_folder + '_tgss.png'
image_data = hdu_list[0].data[0, 0]
try:
imsave(file_url, stretch(image_data), cmap='copper')
except OSError:
logger.info("Something is wrong with the fits file for url = {}".format(url))
logger.error(OSError)
file_url = settings.MEDIA_ROOT + 'database_images/no_image.png'
hdu_list.close()
shutil.rmtree(temp_folder)
return file_url
def image_norm(image_data, stretch=viz.AsinhStretch):
"""
Create the ImageNormalize object based on the desired stretch and
pixel value range.
See http://docs.astropy.org/en/stable/visualization/normalization.html
"""
interval = viz.MinMaxInterval()
vmin, vmax = interval.get_limits(image_data.flatten())
norm = ImageNormalize(vmin=vmin, vmax=vmax, stretch=stretch())
return norm
def plot_norm(self,
stretch='linear',
power=1.0,
asinh_a=0.1,
min_cut=None,
max_cut=None,
min_percent=None,
max_percent=None,
percent=None,
clip=True):
"""Create a matplotlib norm object for plotting.
This is a copy of this function that will be available in Astropy 1.3:
`astropy.visualization.mpl_normalize.simple_norm`
See the parameter description there!
Examples
--------
>>> image = SkyImage()
>>> norm = image.plot_norm(stretch='sqrt', max_percent=99)
>>> image.plot(norm=norm)
"""
import astropy.visualization as v
from astropy.visualization.mpl_normalize import ImageNormalize
if percent is not None:
interval = v.PercentileInterval(percent)
elif min_percent is not None or max_percent is not None:
interval = v.AsymmetricPercentileInterval(min_percent or 0.,
max_percent or 100.)
elif min_cut is not None or max_cut is not None:
interval = v.ManualInterval(min_cut, max_cut)
else:
interval = v.MinMaxInterval()
if stretch == 'linear':
stretch = v.LinearStretch()
elif stretch == 'sqrt':
stretch = v.SqrtStretch()
elif stretch == 'power':
stretch = v.PowerStretch(power)
elif stretch == 'log':
stretch = v.LogStretch()
elif stretch == 'asinh':
stretch = v.AsinhStretch(asinh_a)
else:
raise ValueError('Unknown stretch: {0}.'.format(stretch))
vmin, vmax = interval.get_limits(self.data)
return ImageNormalize(vmin=vmin, vmax=vmax, stretch=stretch, clip=clip)
def download_first_image(url, galaxy):
"""
Download first image from the url
:param url: link of the image
:param galaxy: galaxy object
:return: url of the saved image
"""
stretch = vis.AsinhStretch(0.01) + vis.MinMaxInterval()
file_url = settings.MEDIA_ROOT + 'database_images/' + galaxy.first + '.png'
try:
imsave(file_url, stretch(fits.open(download_file(url, cache=True))[0].data), cmap='inferno')
except OSError:
logger.info("Something is wrong with the fits file for url = {}".format(url))
logger.error(OSError)
file_url = settings.MEDIA_ROOT + 'temp_images/no_image.png'
return file_url
def plot_image_and_lines(cube,
wavs,
xrange,
yrange,
Hbeta_ref=None,
title='',
filename=None,
include_OIII=False):
zpix = np.arange(0, cube.shape[0])
lambda_delta = 5
hbeta_z = np.where((np.array(wavs) > h_beta_std.value-lambda_delta)\
& (np.array(wavs) < h_beta_std.value+lambda_delta))[0]
image = np.mean(cube[min(hbeta_z):max(hbeta_z) + 1, :, :], axis=0)
spect = [
np.mean(cube[z, yrange[0]:yrange[1] + 1, xrange[0]:xrange[1] + 1])
for z in zpix
]
i_peak = spect.index(max(spect))
background_0 = models.Polynomial1D(degree=2)
H_beta_0 = models.Gaussian1D(amplitude=500,
mean=4861,
stddev=1.,
bounds={
'mean': (4855, 4865),
'stddev': (0.1, 5)
})
OIII4959_0 = models.Gaussian1D(amplitude=100,
mean=4959,
stddev=1.,
bounds={
'mean': (4955, 4965),
'stddev': (0.1, 5)
})
OIII5007_0 = models.Gaussian1D(amplitude=200,
mean=5007,
stddev=1.,
bounds={
'mean': (5002, 5012),
'stddev': (0.1, 5)
})
fitter = fitting.LevMarLSQFitter()
if include_OIII is True:
model0 = background_0 + H_beta_0 + OIII4959_0 + OIII5007_0
else:
model0 = background_0 + H_beta_0
model0.mean_1 = wavs[i_peak]
model = fitter(model0, wavs, spect)
residuals = np.array(spect - model(wavs))
plt.figure(figsize=(20, 8))
plt.subplot(1, 4, 1)
plt.title(title)
norm = v.ImageNormalize(image,
interval=v.MinMaxInterval(),
stretch=v.LogStretch(1))
plt.imshow(image, origin='lower', norm=norm)
region_x = [
xrange[0] - 0.5, xrange[1] + 0.5, xrange[1] + 0.5, xrange[0] - 0.5,
xrange[0] - 0.5
]
region_y = [
yrange[0] - 0.5, yrange[0] - 0.5, yrange[1] + 0.5, yrange[1] + 0.5,
yrange[0] - 0.5
]
plt.plot(region_x, region_y, 'r-', alpha=0.5, lw=2)
plt.subplot(1, 4, 2)
if Hbeta_ref is not None:
Hbeta_velocity = (model.mean_1.value * u.Angstrom).to(
u.km / u.s, equivalencies=u.doppler_optical(Hbeta_ref))
title = f'H-beta ({model.mean_1.value:.1f} A, v={Hbeta_velocity.value:.1f} km/s)'
else:
title = f'H-beta ({model.mean_1.value:.1f} A, sigma={model.stddev_1.value:.3f} A)'
plt.title(title)
w = [l for l in np.arange(4856, 4866, 0.05)]
if Hbeta_ref is not None:
vs = [(l * u.Angstrom).to(
u.km / u.s, equivalencies=u.doppler_optical(Hbeta_ref)).value
for l in wavs]
plt.plot(vs, spect, drawstyle='steps-mid', label='data')
vs = [(l * u.Angstrom).to(
u.km / u.s, equivalencies=u.doppler_optical(Hbeta_ref)).value
for l in w]
plt.plot(vs, model(w), 'r-', alpha=0.7, label='Fit')
plt.xlabel('Velocity (km/s)')
plt.xlim(-200, 200)
else:
plt.plot(wavs, spect, drawstyle='steps-mid', label='data')
plt.plot(w, model(w), 'r-', alpha=0.7, label='Fit')
plt.xlabel('Wavelength (angstroms)')
plt.xlim(4856, 4866)
plt.grid()
plt.ylabel('Flux')
plt.legend(loc='best')
plt.subplot(1, 4, 3)
if include_OIII is True:
title = f'OIII 4959 ({model.mean_2.value:.1f} A, sigma={model.stddev_2.value:.3f} A)'
else:
title = f'OIII 4959'
plt.title(title)
plt.plot(wavs, spect, drawstyle='steps-mid', label='data')
w = [l for l in np.arange(4954, 4964, 0.05)]
plt.plot(w, model(w), 'r-', alpha=0.7, label='Fit')
plt.xlabel('Wavelength (angstroms)')
plt.ylabel('Flux')
plt.legend(loc='best')
plt.xlim(4954, 4964)
plt.subplot(1, 4, 4)
if include_OIII is True:
title = f'OIII 5007 ({model.mean_3.value:.1f} A, sigma={model.stddev_3.value:.3f} A)'
else:
title = f'OIII 5007'
plt.title(title)
plt.plot(wavs, spect, drawstyle='steps-mid', label='data')
w = [l for l in np.arange(5002, 5012, 0.05)]
plt.plot(w, model(w), 'r-', alpha=0.7, label='Fit')
plt.xlabel('Wavelength (angstroms)')
plt.ylabel('Flux')
plt.legend(loc='best')
plt.xlim(5002, 5012)
if filename is not None:
plt.savefig(filename, bbox_inches='tight', pad_inches=0.10)
else:
plt.show()
return spect, model
def stretchInterval(self):
if self._stretchInterval is None:
print('Using default MinMaxInterval stretch interval')
return astrovis.MinMaxInterval()
return self._stretchInterval
def set_normalization(self,
stretch=None,
interval=None,
stretchkwargs={},
intervalkwargs={},
perm_linear=None):
if stretch is None:
if self.stretch is None:
stretch = 'linear'
else:
stretch = self.stretch
if isinstance(stretch, str):
print(stretch,
' '.join([f'{k}={v}' for k, v in stretchkwargs.items()]))
if self.data is None: #can not calculate objects yet
self.stretch_kwargs = stretchkwargs
else:
kwargs = self.prepare_kwargs(
self.stretch_kws_defaults[stretch], self.stretch_kwargs,
stretchkwargs)
if perm_linear is not None:
perm_linear_kwargs = self.prepare_kwargs(
self.stretch_kws_defaults['linear'], perm_linear)
print(
'linear', ' '.join([
f'{k}={v}' for k, v in perm_linear_kwargs.items()
]))
if stretch == 'asinh': # arg: a=0.1
stretch = vis.CompositeStretch(
vis.LinearStretch(**perm_linear_kwargs),
vis.AsinhStretch(**kwargs))
elif stretch == 'contrastbias': # args: contrast, bias
stretch = vis.CompositeStretch(
vis.LinearStretch(**perm_linear_kwargs),
vis.ContrastBiasStretch(**kwargs))
elif stretch == 'histogram':
stretch = vis.CompositeStretch(
vis.HistEqStretch(self.data, **kwargs),
vis.LinearStretch(**perm_linear_kwargs))
elif stretch == 'log': # args: a=1000.0
stretch = vis.CompositeStretch(
vis.LogStretch(**kwargs),
vis.LinearStretch(**perm_linear_kwargs))
elif stretch == 'powerdist': # args: a=1000.0
stretch = vis.CompositeStretch(
vis.LinearStretch(**perm_linear_kwargs),
vis.PowerDistStretch(**kwargs))
elif stretch == 'power': # args: a
stretch = vis.CompositeStretch(
vis.PowerStretch(**kwargs),
vis.LinearStretch(**perm_linear_kwargs))
elif stretch == 'sinh': # args: a=0.33
stretch = vis.CompositeStretch(
vis.LinearStretch(**perm_linear_kwargs),
vis.SinhStretch(**kwargs))
elif stretch == 'sqrt':
stretch = vis.CompositeStretch(
vis.SqrtStretch(),
vis.LinearStretch(**perm_linear_kwargs))
elif stretch == 'square':
stretch = vis.CompositeStretch(
vis.LinearStretch(**perm_linear_kwargs),
vis.SquaredStretch())
else:
raise ValueError('Unknown stretch:' + stretch)
else:
if stretch == 'linear': # args: slope=1, intercept=0
stretch = vis.LinearStretch(**kwargs)
else:
raise ValueError('Unknown stretch:' + stretch)
self.stretch = stretch
if interval is None:
if self.interval is None:
interval = 'zscale'
else:
interval = self.interval
if isinstance(interval, str):
print(interval,
' '.join([f'{k}={v}' for k, v in intervalkwargs.items()]))
kwargs = self.prepare_kwargs(self.interval_kws_defaults[interval],
self.interval_kwargs, intervalkwargs)
if self.data is None:
self.interval_kwargs = intervalkwargs
else:
if interval == 'minmax':
interval = vis.MinMaxInterval()
elif interval == 'manual': # args: vmin, vmax
interval = vis.ManualInterval(**kwargs)
elif interval == 'percentile': # args: percentile, n_samples
interval = vis.PercentileInterval(**kwargs)
elif interval == 'asymetric': # args: lower_percentile, upper_percentile, n_samples
interval = vis.AsymmetricPercentileInterval(**kwargs)
elif interval == 'zscale': # args: nsamples=1000, contrast=0.25, max_reject=0.5, min_npixels=5, krej=2.5, max_iterations=5
interval = vis.ZScaleInterval(**kwargs)
else:
raise ValueError('Unknown interval:' + interval)
self.interval = interval
if self.img is not None:
self.img.set_norm(
vis.ImageNormalize(self.data,
interval=self.interval,
stretch=self.stretch,
clip=True))
import matplotlib.pyplot as plt
from astropy.io import fits
import astropy.visualization as viz
image_name = input("Please enter the name of the file : ")
hdul = fits.open(image_name)
hdul.info()
header_number = int(input("Enter Header number whose data you want view : "))
image = hdul[header_number].data
hdul.close()
##stretching and normalizing using LogStretch() and MinMaxInterval() like in DS9
log_param = float(input("Enter base value for logrithmic stretch : "))
norm = viz.ImageNormalize(image,
interval=viz.MinMaxInterval(),
stretch=viz.LogStretch())
plt.imshow(image, cmap='gray')
plt.show()
import random
import keract
plt.style.use("seaborn-darkgrid")
DATA_CSV = '/full/path/to/csv'
IMG_FOLD = '/full/path/to/images' #for me, ends with /Public/EUC_VIS/
DES_IMG_SIZE = 200
NUM_IMAGES = 50000 # can go up to nearly 100000, but there are a few entries with now images
BATCHSIZE = 200
EPOCHS = 20 # I liked doing 20 for quick ones, 40 for longer. maybe we should try more epochs?
# Creating the two normalization objects which
# can also work as functions later on in the
# data preprocessing
norm = avis.MinMaxInterval()
stretch = avis.AsinhStretch(0.010)
def read_csv(filename: str,
num_images: int,
to_skip: list[int] = []) -> pd.DataFrame:
"""
Reads in the csv and trims it down to just the desired size and
necessary columns. Also adds a column of booleans corresponding
to whether a particular observation has been assigned to the
training or testing pool. Training corresponding to True.
"""
df = pd.read_csv(filename, skiprows=26)
df = df[["ID", "n_sources", "n_source_im", "mag_eff", "n_pix_source"]]
df["should_detect"] = ((df["n_source_im"] > 0) & (df["mag_eff"] > 1.6) &
def rgbfig(
figfilename="SgrB2N_RGB.pdf",
lims=[([266.83404223, 266.83172659]), ([-28.373138, -28.3698755])],
scalebarx=coordinates.SkyCoord(266.833545 * u.deg,
-28.37283819 * u.deg),
redfn=paths.Fpath('SGRB2N-2012-Q.DePree_K.recentered.fits'),
greenfn=paths.
Fpath('sgr_b2m.N.B3.allspw.continuum.r0.5.clean1000.image.tt0.pbcor.fits'),
bluefn=paths.
Fpath('sgr_b2m.N.B6.allspw.continuum.r0.5.clean1000.image.tt0.pbcor.fits'),
redpercentile=99.99,
greenpercentile=99.99,
bluepercentile=99.99,
stretch=visualization.AsinhStretch(),
):
header = fits.getheader(redfn)
celwcs = wcs.WCS(header).celestial
redhdu = fits.open(redfn)
greenhdu = fits.open(greenfn)
bluehdu = fits.open(bluefn)
greendata, _ = reproject.reproject_interp(
(greenhdu[0].data, wcs.WCS(greenhdu[0].header).celestial),
celwcs,
shape_out=redhdu[0].data.squeeze().shape)
bluedata, _ = reproject.reproject_interp(
(bluehdu[0].data, wcs.WCS(bluehdu[0].header).celestial),
celwcs,
shape_out=redhdu[0].data.squeeze().shape)
#def rescale(x):
# return (x-np.nanmin(x))/(np.nanmax(x) - np.nanmin(x))
redrescale = visualization.PercentileInterval(redpercentile)
greenrescale = visualization.PercentileInterval(greenpercentile)
bluerescale = visualization.PercentileInterval(bluepercentile)
rgb = np.array([
stretch(redrescale(redhdu[0].data.squeeze())),
stretch(greenrescale(greendata)),
stretch(bluerescale(bluedata)),
]).swapaxes(0, 2).swapaxes(0, 1)
norm = visualization.ImageNormalize(
rgb, interval=visualization.MinMaxInterval(), stretch=stretch)
fig1 = pl.figure(1)
fig1.clf()
ax = fig1.add_subplot(1, 1, 1, projection=celwcs)
pl.imshow(rgb, origin='lower', interpolation='none', norm=norm)
(x1, x2), (y1, y2) = celwcs.wcs_world2pix(lims[0], lims[1], 0)
ax.axis((x1, x2, y1, y2))
visualization_tools.make_scalebar(ax,
left_side=scalebarx,
length=1.213 * u.arcsec,
label='0.05 pc')
pl.savefig(paths.fpath(figfilename), bbox_inches='tight')
position = (x, y)
imData = fileData[0].data[0][0] #Shape it correctly. Assumes 4D. Might rewrite to generalise.
cutout = Cutout2D(imData, position, size, mode='partial') #Anything past the border filled with NaN
image = np.array(cutout.data) #Get the image data as a np array.
empty = np.isnan(image) #Get all NaN pixels and replace with normalised noise.
image[empty] = np.random.normal(loc=np.mean(image[~empty]), scale=np.std(image[~empty]), size=image.shape)[empty] # replace missing values with noise
image = image - np.min(image) #Set base intensity to 0
# clip background
image = np.clip(image, clip_threshold*np.std(image), 1e10)
# Normalize using minmax
mminterval = vis.MinMaxInterval()
image = mminterval(image)
image.astype('f').tofile(output) #Write to the Binary file
#Append the info to our catalogue
entry = []
entry.append(str(ra))
entry.append(str(dec))
entry.append(files_on_hand[i])
file = album + str(count) + '-' + str(int(round(ra))) + ':' + str(int(round(dec))) + '.stamp.fits'
entry.append(file)
info.append(entry)
#Create a FITS image of the stamp
hdu = fits.PrimaryHDU()