def svg_to_image(string, size=None):
""" Convert a SVG document to a QImage.
Parameters
----------
string : basestring
A Python string containing a SVG document.
size : QSize, optional
The size of the image that is produced. If not specified, the SVG
document's default size is used.
Raises
------
ValueError
If an invalid SVG string is provided.
Returns
-------
A QImage of format QImage.Format_ARGB32.
"""
if isinstance(string, unicode_type):
string = string.encode('utf-8')
renderer = QtSvg.QSvgRenderer(QtCore.QByteArray(string))
if not renderer.isValid():
raise ValueError('Invalid SVG data.')
if size is None:
size = renderer.defaultSize()
image = QtGui.QImage(size, QtGui.QImage.Format_ARGB32)
painter = QtGui.QPainter(image)
renderer.render(painter)
return image
def _get_image_tag(self, match, path=None, format="png"):
""" Return (X)HTML mark-up for the image-tag given by match.
Parameters
----------
match : re.SRE_Match
A match to an HTML image tag as exported by Qt, with
match.group("Name") containing the matched image ID.
path : string|None, optional [default None]
If not None, specifies a path to which supporting files may be
written (e.g., for linked images). If None, all images are to be
included inline.
format : "png"|"svg"|"jpg", optional [default "png"]
Format for returned or referenced images.
"""
if format in ("png", "jpg"):
try:
image = self._get_image(match.group("name"))
except KeyError:
return "<b>Couldn't find image %s</b>" % match.group("name")
if path is not None:
ensure_dir_exists(path)
relpath = os.path.basename(path)
if image.save(
"%s/qt_img%s.%s" % (path, match.group("name"), format),
"PNG"):
return '<img src="%s/qt_img%s.%s">' % (
relpath, match.group("name"), format)
else:
return "<b>Couldn't save image!</b>"
else:
ba = QtCore.QByteArray()
buffer_ = QtCore.QBuffer(ba)
buffer_.open(QtCore.QIODevice.WriteOnly)
image.save(buffer_, format.upper())
buffer_.close()
return '<img src="data:image/%s;base64,\n%s\n" />' % (
format,
re.sub(r'(.{60})', r'\1\n',
str(ba.toBase64().data().decode())))
elif format == "svg":
try:
svg = str(self._name_to_svg_map[match.group("name")])
except KeyError:
if not self._svg_warning_displayed:
QtGui.QMessageBox.warning(
self, 'Error converting PNG to SVG.',
'Cannot convert PNG images to SVG, export with PNG figures instead. '
'If you want to export matplotlib figures as SVG, add '
'to your ipython config:\n\n'
'\tc.InlineBackend.figure_format = \'svg\'\n\n'
'And regenerate the figures.', QtGui.QMessageBox.Ok)
self._svg_warning_displayed = True
return (
"<b>Cannot convert PNG images to SVG.</b> "
"You must export this session with PNG images. "
"If you want to export matplotlib figures as SVG, add to your config "
"<span>c.InlineBackend.figure_format = 'svg'</span> "
"and regenerate the figures.")
# Not currently checking path, because it's tricky to find a
# cross-browser way to embed external SVG images (e.g., via
# object or embed tags).
# Chop stand-alone header from matplotlib SVG
offset = svg.find("<svg")
assert (offset > -1)
return svg[offset:]
else:
return '<b>Unrecognized image format</b>'
