def get_backend(self, uri, client):
'''Given the filename of an image, returns (fname, backend)
where fname is the filename to be used (could be the same as
filename, or something different if the image had to be converted
or is missing), and backend is an Image class that can handle
fname.'''
backend = defaultimage
# Extract all the information from the URI
filename, extension, options = self.split_uri(uri)
# If the image doesn't exist, we use a 'missing' image
if not os.path.exists(filename):
log.error("Missing image file: %s", filename)
filename = missing
if extension in ['svg', 'svgz']:
if SVGImage.available():
log.info('Backend for %s is SVGIMage' % filename)
backend = SVGImage
else:
filename = missing
elif extension in [
'ai', 'ccx', 'cdr', 'cgm', 'cmx', 'fig', 'sk1', 'sk', 'xml',
'wmf'
]:
log.info('Backend for %s is VectorImage' % filename)
backend = VectorImage
elif extension in ['pdf']:
if VectorPdf is not None and filename is not missing:
backend = VectorPdf
filename = uri
# PDF images are implemented by converting via PythonMagick
# w,h are in pixels. I need to set the density
# of the image to the right dpi so this
# looks decent
elif LazyImports.PMImage or LazyImports.gfx:
filename = self.raster(filename, client)
else:
log.warning("Minimal PDF image support "\
"requires PythonMagick [%s]", filename)
filename = missing
elif extension != 'jpg' and not LazyImports.PILImage:
if LazyImports.PMImage:
# Need to convert to JPG via PythonMagick
filename = self.raster(filename)
else:
# No way to make this work
log.error('To use a %s image you need PIL installed [%s]',
extension, filename)
filename = missing
return filename, backend
def size_for_node(self, node, client):
'''Given a docutils image node, returns the size the image should have
in the PDF document, and what 'kind' of size that is.
That involves lots of guesswork'''
uri = os.path.join(client.basedir, str(node.get("uri")))
srcinfo = client, uri
# Extract all the information from the URI
imgname, extension, options = self.split_uri(uri)
if not os.path.isfile(imgname):
imgname = missing
scale = float(node.get('scale', 100)) / 100
size_known = False
# Figuring out the size to display of an image is ... annoying.
# If the user provides a size with a unit, it's simple, adjustUnits
# will return it in points and we're done.
# However, often the unit wil be "%" (specially if it's meant for
# HTML originally. In which case, we will use a percentage of
# the containing frame.
# Find the image size in pixels:
kind = 'direct'
xdpi, ydpi = client.styles.def_dpi, client.styles.def_dpi
extension = imgname.split('.')[-1].lower()
if extension in ['svg', 'svgz'] and SVGImage.available():
iw, ih = SVGImage(imgname, srcinfo=srcinfo).wrap(0, 0)
# These are in pt, so convert to px
iw = iw * xdpi / 72
ih = ih * ydpi / 72
elif extension in [
"ai", "ccx", "cdr", "cgm", "cmx", "sk1", "sk", "xml", "wmf",
"fig"
] and VectorImage.available():
iw, ih = VectorImage(imgname, srcinfo=srcinfo).wrap(0, 0)
# These are in pt, so convert to px
iw = iw * xdpi / 72
ih = ih * ydpi / 72
elif extension == 'pdf':
if VectorPdf is not None:
box = VectorPdf.load_xobj(srcinfo).BBox
else:
pdf = LazyImports.pdfinfo
if pdf is None:
log.warning(
'PDF images are not supported without pyPdf or pdfrw [%s]',
nodeid(node))
return 0, 0, 'direct'
reader = pdf.PdfFileReader(open(imgname, 'rb'))
box = [float(x) for x in reader.getPage(0)['/MediaBox']]
x1, y1, x2, y2 = box
# These are in pt, so convert to px
iw = float((x2 - x1) * xdpi / 72)
ih = float((y2 - y1) * ydpi / 72)
size_known = True # Assume size from original PDF is OK
else:
keeptrying = True
if LazyImports.PILImage:
try:
img = LazyImports.PILImage.open(imgname)
img.load()
iw, ih = img.size
xdpi, ydpi = img.info.get('dpi', (xdpi, ydpi))
keeptrying = False
except IOError: # PIL throws this when it's a broken/unknown image
pass
if keeptrying and LazyImports.PMImage:
img = LazyImports.PMImage(imgname)
iw = img.size().width()
ih = img.size().height()
density = img.density()
# The density is in pixelspercentimeter (!?)
xdpi = density.width() * 2.54
ydpi = density.height() * 2.54
keeptrying = False
if keeptrying:
log.error(
"The image (%s, %s) is broken or in an unknown format",
imgname, nodeid(node))
raise ValueError
# Try to get the print resolution from the image itself via PIL.
# If it fails, assume a DPI of 300, which is pretty much made up,
# and then a 100% size would be iw*inch/300, so we pass
# that as the second parameter to adjustUnits
#
# Some say the default DPI should be 72. That would mean
# the largest printable image in A4 paper would be something
# like 480x640. That would be awful.
#
w = node.get('width')
h = node.get('height')
if h is None and w is None: # Nothing specified
# Guess from iw, ih
log.warning(
"Using image %s without specifying size."
"Calculating based on image size at %ddpi [%s]", imgname, xdpi,
nodeid(node))
w = iw * inch / xdpi
h = ih * inch / ydpi
elif w is not None:
# Node specifies only w
# In this particular case, we want the default unit
# to be pixels so we work like rst2html
if w[-1] == '%':
kind = 'percentage_of_container'
w = int(w[:-1])
else:
# This uses default DPI setting because we
# are not using the image's "natural size"
# this is what LaTeX does, according to the
# docutils mailing list discussion
w = client.styles.adjustUnits(w,
client.styles.tw,
default_unit='px')
if h is None:
# h is set from w with right aspect ratio
h = w * ih / iw
else:
h = client.styles.adjustUnits(h,
ih * inch / ydpi,
default_unit='px')
elif h is not None and w is None:
if h[-1] != '%':
h = client.styles.adjustUnits(h,
ih * inch / ydpi,
default_unit='px')
# w is set from h with right aspect ratio
w = h * iw / ih
else:
log.error('Setting height as a percentage does **not** work. '\
'ignoring height parameter [%s]', nodeid(node))
# Set both from image data
w = iw * inch / xdpi
h = ih * inch / ydpi
# Apply scale factor
w = w * scale
h = h * scale
# And now we have this probably completely bogus size!
log.info("Image %s size calculated: %fcm by %fcm [%s]", imgname,
w / cm, h / cm, nodeid(node))
return w, h, kind
def get_backend(self, uri, client):
'''Given the filename of an image, returns (fname, backend)
where fname is the filename to be used (could be the same as
filename, or something different if the image had to be converted
or is missing), and backend is an Image class that can handle
fname.
If uri ensd with '.*' then the returned filename will be the best
quality supported at the moment.
That means: PDF > SVG > anything else
'''
backend = defaultimage
# Extract all the information from the URI
filename, extension, options = self.split_uri(uri)
if '*' in filename:
preferred = ['gif', 'jpg', 'png']
if SVGImage.available():
preferred.append('svg')
preferred.append('pdf')
# Find out what images are available
available = glob.glob(filename)
cfn = available[0]
cv = -10
for fn in available:
ext = fn.split('.')[-1]
if ext in preferred:
v = preferred.index(ext)
else:
v = -1
if v > cv:
cv = v
cfn = fn
# cfn should have our favourite type of
# those available
filename = cfn
extension = cfn.split('.')[-1]
uri = filename
# If the image doesn't exist, we use a 'missing' image
if not os.path.exists(filename):
log.error("Missing image file: %s", filename)
filename = missing
if extension in ['svg', 'svgz']:
if SVGImage.available():
log.info('Backend for %s is SVGIMage' % filename)
backend = SVGImage
else:
filename = missing
elif extension in ['pdf']:
if VectorPdf is not None and filename is not missing:
backend = VectorPdf
filename = uri
# PDF images are implemented by converting via PythonMagick
# w,h are in pixels. I need to set the density
# of the image to the right dpi so this
# looks decent
elif LazyImports.PMImage or LazyImports.gfx:
filename = self.raster(filename, client)
else:
log.warning("Minimal PDF image support "\
"requires PythonMagick or the vectorpdf extension [%s]", filename)
filename = missing
elif extension != 'jpg' and not LazyImports.PILImage:
if LazyImports.PMImage:
# Need to convert to JPG via PythonMagick
filename = self.raster(filename, client)
else:
# No way to make this work
log.error('To use a %s image you need PIL installed [%s]',
extension, filename)
filename = missing
return filename, backend
