def _get_png_info(**kw):
"""\
Returns the width, height and the pixels of the provided PNG file.
"""
reader = PNGReader(**kw)
w, h, pixels, meta = reader.asDirect()
return w, h, _make_pixel_array(pixels, meta['greyscale'])
def append_png_assertion(self, badge):
""" Append the assertion to a PNG file """
badge.signed = _signature
chunks = list()
png = Reader(bytes=badge.source.image)
for chunk in png.chunks():
chunks.append(chunk)
itxt_data = b'openbadges' + pack(
'BBBBB', 0, 0, 0, 0, 0) + badge.get_assertion().encode('utf-8')
itxt = ('iTXt', itxt_data)
chunks.insert(len(chunks) - 1, itxt)
text_data = 'Comment Signed with OpenBadgesLib %s' % __version__
text = ('tEXt', text_data.encode('utf-8'))
chunks.insert(len(chunks) - 1, text)
for tag, data in chunks:
badge.signed = badge.signed + pack("!I", len(data))
tag = tag.encode('iso8859-1')
badge.signed = badge.signed + tag
badge.signed = badge.signed + data
checksum = crc32(tag)
checksum = crc32(data, checksum)
checksum &= 2**32 - 1
badge.signed = badge.signed + pack("!I", checksum)
def load_textures():
global texture
texture = GL.glGenTextures(2)
png_img = Reader(
filename=
'D:\\0\\GitHub\\CEFET-Computacao_Grafica_2020-2\\Trab_08-Esfera_Texturizada\\mapa.png'
)
w, h, pixels, metadata = png_img.read_flat()
if (metadata['alpha']):
modo = GL.GL_RGBA
else:
modo = GL.GL_RGB
GL.glBindTexture(GL.GL_TEXTURE_2D, texture[0])
GL.glPixelStorei(GL.GL_UNPACK_ALIGNMENT, 1)
GL.glTexImage2D(GL.GL_TEXTURE_2D, 0, modo, w, h, 0, modo,
GL.GL_UNSIGNED_BYTE, pixels.tolist())
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_S, GL.GL_REPEAT)
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_T, GL.GL_REPEAT)
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MAG_FILTER,
GL.GL_NEAREST)
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MIN_FILTER,
GL.GL_NEAREST)
GL.glTexEnvf(GL.GL_TEXTURE_ENV, GL.GL_TEXTURE_ENV_MODE, GL.GL_DECAL)
def _get_png_info(**kw):
"""\
Returns the width, height and the pixels of the provided PNG file.
"""
reader = PNGReader(**kw)
w, h, pixels, meta = reader.asDirect()
return w, h, _make_pixel_array(pixels, meta['greyscale'])
def test_greyscale():
qr = segno.make_qr('test')
buff = io.BytesIO()
qr.save(buff, kind='png', quiet_zone='white')
buff.seek(0)
reader = PNGReader(file=buff)
reader.preamble()
assert reader.greyscale
def extract_png_assertion(file_data):
png = Reader(bytes=file_data)
for tag, data in png.chunks():
if tag == 'iTXt':
fmt_len = len(data) - 15 # 15=len('openbadges'+pack('BBBBB'))
fmt = '<10s5B%ds' % fmt_len
return Assertion.decode(unpack(fmt, data)[6])
def textureTest():
help(Reader)
r = Reader(file=open('tesx.png'))
rgb = list(r.asRGBA()[2])
print len(rgb),len(rgb[0])
img = Image(500,500)
drawTexturedTri(150,150,300,100,100,300,1,0,0,1,1,1,rgb,(255,255,0),img)
img.savePpm('t.ppm')
def has_png_assertion(self, badge):
png = Reader(bytes=badge.image)
for tag, data in png.chunks():
if tag == 'iTXt':
if data.startswith(b'openbadges'):
return True
return False
def test_greyscale():
fn = _make_tmp_png_filename()
res = cli.main(['--quiet-zone=white', '--output={0}'.format(fn), 'test'])
with open(fn, 'rb') as f:
data = io.BytesIO(f.read())
os.unlink(fn)
assert 0 == res
reader = PNGReader(file=data)
reader.preamble()
assert reader.greyscale
def test_png_file(filename: str) -> None:
"""
Takes the relative filename of a PNG file and draws the quadtree on top of it
:param filename:
:return:
"""
reader = Reader(filename)
pngdata = reader.read() #extract file
matrix = numpy.array([[y//255 for y in x] for x in list(pngdata[2])])[:, ::3] # load into numpy array
lqtld = trees.LinearQuadTree(value_matrix=matrix)
lqtld.draw_all_usable_cells()
lqtld.generate_debug_png('../output.png')
def to_fits(self, out_file):
"""
Converts a PNG to file a FITS file.
:param out_file: User specified filename for the FITS
"""
if not self.png:
raise ValueError, "AstroPNG was not initialized with a PNG image"
# Reading the PNG takes two passes (for now)
r = Reader(self.png)
width, height, imgdata, metadata = r.read()
fluxes = numpy.vstack( itertools.imap(numpy.uint16, imgdata) )
r = Reader(self.png)
chunks = r.chunks()
has_fits = False
has_quantization = False
has_nans = False
# Read the custom astro chunks
while True:
try:
chunk_name, data = chunks.next()
except:
break
if chunk_name == 'fITS':
header = self.__read_fits_header(data)
has_fits = True
elif chunk_name == 'qANT':
zzero, zscale = self.__read_quantization_parameters(data, height)
has_quantization = True
elif chunk_name == 'nANS':
y_nans, x_nans = self.__read_nan_locations(data)
has_nans = True
elif chunk_name == 'iEND':
break
if has_quantization:
random_numbers = self.__random_number_generator(N = width * height).reshape( (height, width) )
fluxes = (fluxes - random_numbers + 0.5) * numpy.vstack(zscale) + numpy.vstack(zzero)
if has_nans:
if y_nans.size > 0:
fluxes[y_nans, x_nans] = numpy.nan
fluxes = numpy.flipud(fluxes)
hdu = pyfits.PrimaryHDU(fluxes, header)
hdu.verify()
hdu.writeto(out_file, output_verify='ignore')
def test_plte():
qr = segno.make_qr('test')
buff = io.BytesIO()
dark = (0, 0, 139)
qr.save(buff, kind='png', dark=dark, light=None)
buff.seek(0)
reader = PNGReader(file=buff)
reader.preamble()
assert not reader.greyscale
palette = reader.palette()
assert 2 == len(palette)
assert 0 == palette[0][3] # Transparent color
dark_with_alpha = dark + (255, )
assert dark_with_alpha in palette
def test_plte_no_transparency():
qr = segno.make_qr('test')
buff = io.BytesIO()
dark = (0, 0, 139)
light = (255, 255, 255)
qr.save(buff, kind='png', dark=dark, light=light)
buff.seek(0)
reader = PNGReader(file=buff)
reader.preamble()
assert not reader.greyscale
palette = reader.palette()
assert 2 == len(palette)
assert dark in palette
assert light in palette
def test_not_greyscale():
qr = segno.make_qr('test')
buff = io.BytesIO()
qr.save(buff, kind='png',
quiet_zone=None) # Three "colors": white, black, transparent
buff.seek(0)
reader = PNGReader(file=buff)
reader.preamble()
assert not reader.greyscale
palette = reader.palette()
assert 3 == len(palette)
assert 0 == palette[0][3] # Transparent color
assert (0, 0, 0, 255) in palette # black
assert (255, 255, 255, 255) in palette # white
def one_channel_image_reader(filepath,
datatype,
input_has_three_channels=True):
"""Labels are stored in a crude way into the png format that cannot be handled by
standard libraries. Therefore, we have to create this decoder."""
im = Reader(filepath)
_, _, array, _ = im.asDirect()
array = np.vstack(itertools.imap(datatype, array))
if input_has_three_channels:
# This image array is now in 'boxed row flat pixel' format, meaning that each row
# is just a continuous list of R, G, B, R, G, B, R, ... values.
# We are in this case only interested in the first component, which holds the
# class label, therefore we take every third value.
array = array[:, range(0, array.shape[1], 3)]
return datatype(array)
def __readPngFile(self):
with open(self._s_file, "rb") as fs:
_reader = Reader(file=fs)
_data = _reader.read()
_colorarray = []
for frame in list(_data[2]):
framearray = list(frame)
_colorarray.append([
framearray[x:x + 3] for x in range(0, len(framearray), 3)
])
self.__nbleds = _data[0]
self.__nbframes = _data[1]
self.__data = _colorarray
def test_not_greyscale():
fn = _make_tmp_png_filename()
res = cli.main(
['--quiet-zone=transparent', '--output={0}'.format(fn), 'test'])
with open(fn, 'rb') as f:
data = io.BytesIO(f.read())
os.unlink(fn)
assert 0 == res
reader = PNGReader(file=data)
reader.preamble()
assert not reader.greyscale
palette = reader.palette()
assert 3 == len(palette)
assert 0 == palette[0][3] # Transparent color
assert (0, 0, 0, 255) in palette # black
assert (255, 255, 255, 255) in palette # white
def load():
global textura
textura = GL.glGenTextures(2)
imagem = Reader(filename='C:\\Users\\Pedro\\Desktop\\computacao grafica\\trabalhos cg 2021.1\\7 - globo textura\\globomodelo.png')
w, h, pixels, metadata = imagem.read_flat()
if(metadata['alpha']):
mod = GL.GL_RGBA
else:
mod = GL.GL_RGB
GL.glBindTexture(GL.GL_TEXTURE_2D, textura[0])
GL.glPixelStorei(GL.GL_UNPACK_ALIGNMENT, 1)
GL.glTexImage2D(GL.GL_TEXTURE_2D, 0, mod, w, h, 0, mod, GL.GL_UNSIGNED_BYTE, pixels.tolist())
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_S, GL.GL_REPEAT)
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_T, GL.GL_REPEAT)
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MAG_FILTER, GL.GL_NEAREST)
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MIN_FILTER, GL.GL_NEAREST)
GL.glTexEnvf(GL.GL_TEXTURE_ENV, GL.GL_TEXTURE_ENV_MODE, GL.GL_DECAL)
def test_png_gen_greyscale_works():
alpha_ch = np.array([[1, 1, 1]])
gen = PngGenerator(alpha_ch, greyscale=True)
img_data = np.array([[0.0, 5.0, 10.0]])
norm_img_data = (img_data - img_data.min()) / (img_data.max() -
img_data.min())
img_bytes = gen.generate_png(img_data)
reader = Reader(bytes=img_bytes)
width, height, pixels, _ = reader.asFloat()
assert_equal(width, 3)
assert_equal(height, 1)
grey_shape = img_data.shape + (2, )
assert_almost_equal(np.array(list(pixels)).reshape(grey_shape)[:, :, 0],
norm_img_data,
decimal=4)
def load_image(filename):
"""Given the file name of a PNG file, create and return an Image object
representing the image.
"""
if not isfile(filename):
raise ValueError("file '" + filename + "' cannot be found")
reader = Reader(filename)
num_cols, num_rows, pixels, _ = reader.asRGBA()
rows = []
for row in pixels:
# note: each 'row' from this iterator is an array, so we call
# its tolist() method here and box it
rows.append(_box(row.tolist(), input_type='rgba'))
img = Image(num_rows, num_cols)
img.image_data = rows
return img
def generate_spectrogram_file(self, audio: AudioRecording):
prefilter = settings.SPECTROGRAM_PREFILTER
credit = settings.SPECTROGRAM_CREDIT
title = '(unknown) '
if audio.species:
title = f'{audio.genus} {audio.species} '
try:
species = self.species_lookup.species_by_abbreviations(
audio.genus, audio.species)
except NonUniqueSpeciesLookup:
species = None
if species:
species_ucfirst = species.species[0].upper(
) + species.species[1:]
if species.common_name:
title = f'{species.common_name} ({species.genus} {species_ucfirst}) '
else:
title = f'{species.genus} {species_ucfirst} '
if audio.recorded_at_iso:
title += date_parser.parse(
audio.recorded_at_iso).strftime('%Y-%m-%d %H:%M')
if not audio.id:
audio.save()
dest = os.path.join(settings.MEDIA_ROOT, 'processed', 'spectrograms',
f'{audio.id}-{audio.identifier}.png')
print(f'Plot {audio.audio_file} spectrum to {dest}')
# sox "$file" -n spectrogram -o "$outfile" -t "$ident"
sox_result = subprocess.run([
self.sox_executable,
audio.audio_file,
'-n',
] + prefilter + ['spectrogram', '-o', dest, '-c', credit, '-t', title])
sox_result.check_returncode()
png_reader = Reader(filename=dest)
(width, height, _, _) = png_reader.read()
audio.spectrogram_image_file = dest
audio.spectrogram_image_width = width
audio.spectrogram_image_height = height
def load_image(filename):
"""Given the file name of a PNG file, create and return an Image object
representing the image.
"""
if not isfile(filename):
raise ValueError("file '" + filename + "' cannot be found")
reader = Reader(filename)
num_cols, num_rows, pixels, _ = reader.asRGBA()
rows = []
for row in pixels:
# note: each 'row' from this iterator is an array, so we call
# its tolist() method here and box it
rows.append(_box(row.tolist(), input_type='rgba'))
img = Image(num_rows, num_cols)
img.image_data = rows
return img
def test_plte_colors():
fn = _make_tmp_png_filename()
res = cli.main([
'--quiet-zone=green', '--finder-dark=purple', '--finder-light=yellow',
'--output={0}'.format(fn), 'test'
])
with open(fn, 'rb') as f:
data = io.BytesIO(f.read())
os.unlink(fn)
assert 0 == res
reader = PNGReader(file=data)
reader.preamble()
assert not reader.greyscale
palette = reader.palette()
assert 5 == len(palette)
assert (0, 0, 0) in palette
assert (255, 255, 255) in palette
assert colors._color_to_rgb('green') in palette
assert colors._color_to_rgb('purple') in palette
assert colors._color_to_rgb('yellow') in palette
def LoadTextures():
global texture
texture = GL.glGenTextures(2)
###############################################################################################
reader = Reader(filename='C:\\Users\\user\\Desktop\\computação grafica\\mapa.png')
w, h, pixels, metadata = reader.read_flat()
if(metadata['alpha']):
modo = GL.GL_RGBA
else:
modo = GL.GL_RGB
GL.glBindTexture(GL.GL_TEXTURE_2D, texture[0])
GL.glPixelStorei(GL.GL_UNPACK_ALIGNMENT, 1)
GL.glTexImage2D(GL.GL_TEXTURE_2D, 0, modo, w, h, 0, modo, GL.GL_UNSIGNED_BYTE, pixels.tolist())
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_S, GL.GL_REPEAT)
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_WRAP_T, GL.GL_REPEAT)
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MAG_FILTER, GL.GL_NEAREST)
GL.glTexParameterf(GL.GL_TEXTURE_2D, GL.GL_TEXTURE_MIN_FILTER, GL.GL_NEAREST)
GL.glTexEnvf(GL.GL_TEXTURE_ENV, GL.GL_TEXTURE_ENV_MODE, GL.GL_DECAL)
def load_textures():
global texture
texture = glGenTextures(2)
mapa = Reader(filename='./mapa.png')
w, h, pixels, metadata = mapa.read_flat()
if (metadata['alpha']):
modo = GL_RGBA
else:
modo = GL_RGB
glBindTexture(GL_TEXTURE_2D, texture[0])
glPixelStorei(GL_UNPACK_ALIGNMENT, 1)
glTexImage2D(GL_TEXTURE_2D, 0, modo, w, h, 0, modo, GL_UNSIGNED_BYTE,
pixels.tolist())
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT)
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT)
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST)
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST)
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL)
def test_issue_54_notinverted(dark, light, transparent):
qr = segno.make('The Beatles')
assert 'M4-M' == qr.designator
out = io.BytesIO()
scale = 5
qr.save(out, kind='png', scale=scale, dark=dark, light=light)
out.seek(0)
reader = PNGReader(file=out)
w, h, pixels, meta = reader.read()
width, height = qr.symbol_size(scale=scale)
assert width == w
assert height == h
assert meta['greyscale']
border_row = tuple([1] * w)
expected_row = tuple([1] * 2 * scale + [0] * 7 * scale + [1])
for idx, row in enumerate(pixels):
if idx < 10:
assert border_row == tuple(row)
elif idx == 10:
assert expected_row == tuple(row)[:len(expected_row)]
break
assert transparent == reader.transparent
def test_plte_colors():
qr = segno.make_qr('test')
buff = io.BytesIO()
dark = (0, 0, 139)
light = (255, 255, 255)
qr.save(buff,
kind='png',
dark=dark,
light=light,
quiet_zone='green',
finder_dark='purple',
finder_light='yellow')
buff.seek(0)
reader = PNGReader(file=buff)
reader.preamble()
assert not reader.greyscale
palette = reader.palette()
assert 5 == len(palette)
assert dark in palette
assert light in palette
assert colors._color_to_rgb('green') in palette
assert colors._color_to_rgb('purple') in palette
assert colors._color_to_rgb('yellow') in palette
from png import Reader
FILENAME = "target_gradent.png"
background = Actor("background")
background.web_color = "#000000"
with open(FILENAME, 'rb') as f:
reader = Reader(file=f)
file_data = reader.read()
"""
(686,
300,
<map at 0x7f153a04aa20>,
{'alpha': True,
'size': (686, 300),
'planes': 4,
'interlace': 0,
'bitdepth': 8,
'greyscale': False,
'background': (255, 255, 255)})
"""
image_width, image_height = file_data[0], file_data[1]
# take the three ranges (drop alpha) for the whole width
#colors = [c[:3] for c in list(zip(*list(file_data[2])))[:image_width]]
#colors = list(file_data[2])
raw = list(file_data[2])[0]
colors = list(zip(raw[::4], raw[1::4], raw[2::4]))
go_and_back_colors = colors + colors[::-1]
def getTexture(texture, texcache):
if texture not in texcache:
r = Reader(texture)
rgb = list(r.asRGBA()[2])
texcache[texture] = rgb
return texcache[texture]
def main():
comm = MPI.COMM_WORLD
id= comm.Get_rank()
wsize= comm.Get_size()
tstart = MPI.Wtime()
fsky = open("skymap.png","r")
reader = Reader(fsky)
skypixelwidth, skypixelheight, skypixels, metadata=reader.read_flat()
pixelwidth = int(argv[1])
pixelheight = int(argv[2])
tskymapstart = MPI.Wtime()
telepixels = np.zeros((pixelwidth*pixelheight*3),dtype=np.uint8)
colorpixels = np.zeros((pixelwidth*pixelheight),dtype=np.uint8)
skystartall = np.zeros((pixelwidth*pixelheight),dtype=np.uint32)
telestartall = np.zeros((pixelwidth*pixelheight),dtype=np.uint32)
colorall = np.zeros((pixelwidth*pixelheight),dtype=np.uint8)
totnstepsall=np.zeros((wsize),dtype=np.uint32)
tskymapend = MPI.Wtime()
tskymap = tskymapend-tskymapstart
tmin = 1.e6
tpercparmin=1.e6
hinit=1.e-1
#h=1.e-4
Router = 1000.
Rplane = 700.
Rs = 2.
every = 1
deltalamb = 1.e-1
imagewidth = 50;
imageheight = 50;
tiny = 1.e-30
epsilon=1.e-8
eccentricity = 0.2
Rfac = 1.+1.e-10
heps = 1.e-14
semilatusr = 10.0
tstartpp=MPI.Wtime() #percent parallelized
numperprocess = pixelheight*pixelwidth/wsize
skystart=np.zeros((numperprocess),dtype=np.int32)
telestart=np.zeros((numperprocess),dtype=np.int32)
color = np.zeros((numperprocess),dtype=np.int8)
totnsteps=np.zeros((numperprocess),dtype=np.int32)
trk4all=np.zeros((numperprocess),dtype=np.float)
ttelestop = MPI.Wtime()
ttele = ttelestop-tstartpp
trk4=float("inf")
for index in range(numperprocess):
ypix = int((id*numperprocess+index)/pixelwidth)
xpix = (id*numperprocess+index)%pixelwidth
tstartrk4=MPI.Wtime()
totnsteps[index],skystart[index],telestart[index],color[index]=integrateNullGeodesic(xpix, ypix, pixelheight,pixelwidth, skypixelheight,skypixelwidth,imagewidth,imageheight,Rs,Router,Rplane,eccentricity, semilatusr, epsilon, tiny, hinit,Rfac,heps)
tendrk4=MPI.Wtime()
trk4=min(trk4,(tendrk4-tstartrk4)/float(totnsteps[index]))
totnstepsmax=max(totnsteps)
tstoppp = MPI.Wtime()
tpercpar=tstoppp-tstartpp
comm.Barrier()
if id==0:
totnstepsmaxall=0
else:
totnstepsmaxall=None
comm.Barrier()
totnstepsmaxall=comm.reduce(totnstepsmax,op=MPI.MAX,root=0)
tskymapall = comm.reduce(tskymap, op=MPI.MAX, root=0)
tteleall = comm.reduce(ttele,op=MPI.MAX,root=0)
comm.Gatherv(skystart,skystartall,root=0)
comm.Gatherv(telestart, telestartall, root=0)
comm.Gatherv(color,colorall, root=0)
trk4min=comm.reduce(trk4,op=MPI.MIN,root=0)
comm.Barrier()
tend = MPI.Wtime()
tall = tend-tstart
if id==0:
tindexstart = MPI.Wtime()
for index in range(pixelheight*pixelwidth):
if(colorall[index]==1):
telepixels[telestartall[index]:telestartall[index]+3]=skypixels[skystartall[index]:skystartall[index]+3]
else:
telepixels[telestartall[index]]=255 #leave other two indices zero,red
tindexend = MPI.Wtime()
tindex = tindexend-tindexstart
if id==0:
twritestart = MPI.Wtime()
ftele = open('teleview_{pw}_{ph}_{ws}.png'.format(pw=pixelwidth,ph=pixelheight,ws=wsize), "w")
telewrite=Writer(width=pixelwidth,height=pixelheight,greyscale=False,alpha=False)
telewrite.write_array(ftele,telepixels)
ftele.close()
twriteend=MPI.Wtime()
twrite = twriteend-twritestart
fsky.close()
comm.Barrier()
tmax = comm.reduce(tall,MPI.MAX,root=0)
tpercparmin = comm.reduce(tpercpar/tall,op=MPI.MIN,root=0)
comm.Barrier()
if (id==0):
# print("Telescope dimensions in M", 2.*imagewidth, 2.*imageheight)
# print("Telescope resolution", pixelwidth, pixelheight)
# print("Skymap resolution", skypixelwidth, skypixelheight)
# print("Schwarzschild radius in M", 2.*Rs)
# print("Outer radius in M", 2.*Router)
# print("Telescope radius in M", 2.*Rplane)
# print("Number of processes = ",wsize)
# print("Maximum number of integration steps taken is",totnstepsmaxall)
# print("The time for a single step of the RK4 is",trk4min)
# print("Total runtime = ",tmax)
# print("Fraction parallel = ", tpercparmin)
print pixelwidth,pixelheight,wsize,totnstepsmaxall,trk4min,tmax,tpercparmin, tindex, twrite, tskymapall, tteleall
MPI.Finalize()
def to_liq(image: png.Reader, attr: liq.Attr) -> liq.Image:
"""
Convert png.Reader to liq.Image.
"""
width, height, data, info = image.read_flat()
return attr.create_rgba(data, width, height, info.get('gamma', 0))