def check_large_images(self, node, parent_depth_level, sibling_depth_level):
"""\
although slow the best way to determine the best image is to download
them and check the actual dimensions of the image when on disk
so we'll go through a phased approach...
1. get a list of ALL images from the parent node
2. filter out any bad image names that we know of (gifs, ads, etc..)
3. do a head request on each file to make sure it meets
our bare requirements
4. any images left over let's do a full GET request,
download em to disk and check their dimensions
5. Score images based on different factors like height/width
and possibly things like color density
"""
good_images = self.get_image_candidates(node)
if good_images:
scored_images = self.fetch_images(good_images, parent_depth_level)
if scored_images:
highscore_image = sorted(list(scored_images.items()),
key=lambda x: x[1], reverse=True)[0][0]
main_image = Image()
main_image.src = highscore_image.src
main_image.extraction_type = "bigimage"
main_image.confidence_score = 100 / len(scored_images) \
if len(scored_images) > 0 else 0
return main_image
depth_obj = self.get_depth_level(node, parent_depth_level, sibling_depth_level)
if depth_obj:
return self.check_large_images(depth_obj.node,
depth_obj.parent_depth, depth_obj.sibling_depth)
return None
def scored_image_to_result_image(self, scored_img, scored_imgs_len):
img = Image()
img.src = scored_img.src
img.width = scored_img.width
img.height = scored_img.height
img.extraction_type = "bigimage"
img.confidence_score = 100 / scored_imgs_len
return img
def get_best_image(self, doc, topNode):
image = self.check_known_elements()
if image:
return image
image = self.check_large_images(topNode, 0, 0)
if image:
return image
image = self.check_meta_tag()
if image:
return image
return Image()
def get_image(self, element, src, score=100, extraction_type="N/A"):
# build the Image object
image = Image()
image.src = self.build_image_path(src)
image.extraction_type = extraction_type
image.confidence_score = score
# check if we have a local image
# in order to add more information
# on the Image object
local_image = self.get_local_image(image.src)
if local_image:
image.bytes = local_image.bytes
image.height = local_image.height
image.width = local_image.width
# return the image
return image
def check_known_elements(self):
"""\
in here we check for known image contains from sites
we've checked out like yahoo, techcrunch, etc... that have
* known places to look for good images.
* TODO: enable this to use a series of settings files
so people can define what the image ids/classes
are on specific sites
"""
domain = self.get_clean_domain()
if domain in self.custom_site_mapping.keys():
classes = self.custom_site_mapping.get(domain).split('|')
for classname in classes:
KNOWN_IMG_DOM_NAMES.append(classname)
known_image = None
for known_name in KNOWN_IMG_DOM_NAMES:
known = self.parser.getElementById(self.article.raw_doc, known_name)
if not known:
known = self.parser.getElementsByTag(self.article.raw_doc,
attr='class', value=known_name)
if known:
known = known[0]
if known:
main_image = self.parser.getElementsByTag(known, tag='img')
if main_image:
known_image = main_image[0]
if known_image is not None:
known_image_source = self.parser.getAttribute(known_image, attr='src')
main_image = Image()
main_image.src = self.build_image_path(known_image_source)
main_image.extraction_type = "known"
main_image.confidence_score = 90
local_image = self.get_local_image(main_image.src)
if local_image:
main_image.bytes = local_image.bytes
main_image.height = local_image.height
main_image.width = local_image.width
return main_image
def check_opengraph_tag(self):
"""\
checks to see if we were able to
find open graph tags on this page
"""
node = self.article.raw_doc
meta = self.parser.getElementsByTag(node, tag='meta', attr='property', value='og:image')
for item in meta:
href = self.parser.getAttribute(item, attr='content')
if href:
main_image = Image()
main_image.src = href
main_image.extraction_type = "opengraph"
main_image.confidence_score = 100
local_image = self.get_local_image(main_image.src)
if local_image:
main_image.bytes = local_image.bytes
main_image.height = local_image.height
main_image.width = local_image.width
return main_image
return None
def check_link_tag(self):
"""\
checks to see if we were able to
find open link_src on this page
"""
node = self.article.raw_doc
meta = self.parser.getElementsByTag(node, tag='link', attr='rel', value='image_src')
for item in meta:
href = self.parser.getAttribute(item, attr='href')
if href:
main_image = Image()
main_image.src = href
main_image.extraction_type = "linktag"
main_image.confidence_score = 100
local_image = self.get_local_image(main_image.src)
if local_image:
main_image.bytes = local_image.bytes
main_image.height = local_image.height
main_image.width = local_image.width
return main_image
return None
def getExpectedImage(self, expected_value):
image = Image()
for k, v in expected_value.items():
setattr(image, k, v)
return image