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# -*- coding: utf-8 -*- # """ Image Process ============= This plugin process images according to their class attribute. """ from __future__ import unicode_literals import copy import collections import functools import os.path import re import six from PIL import Image, ImageFilter from bs4 import BeautifulSoup from pelican import signals IMAGE_PROCESS_REGEX = re.compile("image-process-[-a-zA-Z0-9_]+") Path = collections.namedtuple( 'Path', ['base_url', 'source', 'base_path', 'filename', 'process_dir'] ) def convert_box(image, t, l, r, b): """Convert box coordinates strings to integer. t, l, r, b (top, left, right, bottom) must be strings specifying either a number or a percentage. """ bbox = image.getbbox() iw = bbox[2] - bbox[0] ih = bbox[3] - bbox[1] if t[-1] == '%': t = ih * float(t[:-1]) / 100. else: t = float(t) if l[-1] == '%': l = iw * float(l[:-1]) / 100. else: l = float(l) if r[-1] == '%': r = iw * float(r[:-1]) / 100. else: r = float(r) if b[-1] == '%': b = ih * float(b[:-1]) / 100. else: b = float(b) return (t, l, r, b) def crop(i, t, l, r, b): """Crop image i to the box (l,t)-(r,b). t, l, r, b (top, left, right, bottom) must be strings specifying either a number or a percentage. """ t, l, r, b = convert_box(i, t, l, r, b) return i.crop((int(t), int(l), int(r), int(b))) def resize(i, w, h): """Resize the image to the dimension specified. w, h (width, height) must be strings specifying either a number or a percentage. """ _, _, w, h = convert_box(i, '0', '0', w, h) if i.mode == 'P': i = i.convert('RGBA') elif i.mode == '1': i = i.convert('L') return i.resize((int(w), int(h)), Image.LANCZOS) def scale(i, w, h, upscale, inside): """Resize the image to the dimension specified, keeping the aspect ratio. w, h (width, height) must be strings specifying either a number or a percentage, or "None" to ignore this constraint. If upscale is True, upscaling is allowed. If inside is True, the resulting image will not be larger than the dimensions specified, else it will not be smaller. """ bbox = i.getbbox() iw = bbox[2] - bbox[0] ih = bbox[3] - bbox[1] if w == 'None': w = 1. elif w[-1] == '%': w = float(w[:-1]) / 100. else: w = float(w) / iw if h == 'None': h = 1. elif h[-1] == '%': h = float(h[:-1]) / 100. else: h = float(h) / ih if inside: scale = min(w, h) else: scale = max(w, h) if upscale in [0, '0', 'False', False]: scale = min(scale, 1.) if i.mode == 'P': i = i.convert('RGBA') elif i.mode == '1': i = i.convert('L') return i.resize((int(scale*iw), int(scale*ih)), Image.LANCZOS) def rotate(i, degrees): if i.mode == 'P': i = i.convert('RGBA') elif i.mode == '1': i = i.convert('L') # rotate does not support the LANCZOS filter (Pillow 2.7.0). return i.rotate(int(degrees), Image.BICUBIC, True) def apply_filter(i, f): if i.mode == 'P': i = i.convert('RGBA') elif i.mode == '1': i = i.convert('L') return i.filter(f) basic_ops = { 'crop': crop, 'flip_horizontal': lambda i: i.transpose(Image.FLIP_LEFT_RIGHT), 'flip_vertical': lambda i: i.transpose(Image.FLIP_TOP_BOTTOM), 'grayscale': lambda i: i.convert('L'), 'resize': resize, 'rotate': rotate, 'scale_in': functools.partial(scale, inside=True), 'scale_out': functools.partial(scale, inside=False), 'blur': functools.partial(apply_filter, f=ImageFilter.BLUR), 'contour': functools.partial(apply_filter, f=ImageFilter.CONTOUR), 'detail': functools.partial(apply_filter, f=ImageFilter.DETAIL), 'edge_enhance': functools.partial(apply_filter, f=ImageFilter.EDGE_ENHANCE), 'edge_enhance_more': functools.partial(apply_filter, f=ImageFilter.EDGE_ENHANCE_MORE), 'emboss': functools.partial(apply_filter, f=ImageFilter.EMBOSS), 'find_edges': functools.partial(apply_filter, f=ImageFilter.FIND_EDGES), 'smooth': functools.partial(apply_filter, f=ImageFilter.SMOOTH), 'smooth_more': functools.partial(apply_filter, f=ImageFilter.SMOOTH_MORE), 'sharpen': functools.partial(apply_filter, f=ImageFilter.SHARPEN), } def harvest_images(path, context): # Set default value for 'IMAGE_PROCESS_DIR'. if 'IMAGE_PROCESS_DIR' not in context: context['IMAGE_PROCESS_DIR'] = 'derivatives' with open(path, 'r+') as f: res = harvest_images_in_fragment(f, context) f.seek(0) f.truncate() f.write(res) def harvest_images_in_fragment(fragment, settings): parser = settings.get("IMAGE_PROCESS_PARSER", "html.parser") soup = BeautifulSoup(fragment, parser) for img in soup.find_all('img', class_=IMAGE_PROCESS_REGEX): for c in img['class']: if c.startswith('image-process-'): derivative = c[14:] break else: continue try: d = settings['IMAGE_PROCESS'][derivative] except KeyError: raise RuntimeError('Derivative %s undefined.' % derivative) if isinstance(d, list): # Single source image specification. process_img_tag(img, settings, derivative) elif not isinstance(d, dict): raise RuntimeError('Derivative %s definition not handled' '(must be list or dict)' % (derivative)) elif 'type' not in d: raise RuntimeError('"type" is mandatory for %s.' % derivative) elif d['type'] == 'image': # Single source image specification. process_img_tag(img, settings, derivative) elif d['type'] == 'responsive-image': # srcset image specification. build_srcset(img, settings, derivative) elif d['type'] == 'picture': # Multiple source (picture) specification. group = img.find_parent() if group.name == 'div': convert_div_to_picture_tag(soup, img, group, settings, derivative) elif group.name == 'picture': process_picture(soup, img, group, settings, derivative) return str(soup) def compute_paths(img, settings, derivative): process_dir = settings['IMAGE_PROCESS_DIR'] url_path, filename = os.path.split(img['src']) base_url = os.path.join(url_path, process_dir, derivative) for f in settings['filenames']: if os.path.basename(img['src']) in f: source = settings['filenames'][f].source_path base_path = os.path.join(settings['OUTPUT_PATH'], os.path.dirname(settings['filenames'][f].save_as), process_dir, derivative) break else: source = os.path.join(settings['PATH'], img['src'][1:]) base_path = os.path.join(settings['OUTPUT_PATH'], base_url[1:]) return Path(base_url, source, base_path, filename, process_dir) def process_img_tag(img, settings, derivative): path = compute_paths(img, settings, derivative) process = settings['IMAGE_PROCESS'][derivative] img['src'] = os.path.join(path.base_url, path.filename) destination = os.path.join(path.base_path, path.filename) if not isinstance(process, list): process = process['ops'] process_image((path.source, destination, process), settings) def build_srcset(img, settings, derivative): path = compute_paths(img, settings, derivative) process = settings['IMAGE_PROCESS'][derivative] default = process['default'] if isinstance(default, six.string_types): default_name = default elif isinstance(default, list): default_name = 'default' destination = os.path.join(path.base_path, default_name, path.filename) process_image((path.source, destination, default), settings) img['src'] = os.path.join(path.base_url, default_name, path.filename) if 'sizes' in process: img['sizes'] = process['sizes'] srcset = [] for src in process['srcset']: file_path = os.path.join(path.base_url, src[0], path.filename) srcset.append("%s %s" % (file_path, src[0])) destination = os.path.join(path.base_path, src[0], path.filename) process_image((path.source, destination, src[1]), settings) if len(srcset) > 0: img['srcset'] = ', '.join(srcset) def convert_div_to_picture_tag(soup, img, group, settings, derivative): """ Convert a div containing multiple images to a picture. """ process_dir = settings['IMAGE_PROCESS_DIR'] # Compile sources URL. Special source "default" uses the main # image URL. Other sources use the img with classes # [source['name'], 'image-process']. We also remove the img from # the DOM. sources = copy.deepcopy(settings['IMAGE_PROCESS'][derivative]['sources']) for s in sources: if s['name'] == 'default': s['url'] = img['src'] else: candidates = group.find_all('img', class_=s['name']) for candidate in candidates: if 'image-process' in candidate['class']: s['url'] = candidate['src'] candidate.decompose() break url_path, s['filename'] = os.path.split(s['url']) s['base_url'] = os.path.join(url_path, process_dir, derivative) s['base_path'] = os.path.join(settings['OUTPUT_PATH'], s['base_url'][1:]) # If default is not None, change default img source to the image # derivative referenced. default = settings['IMAGE_PROCESS'][derivative]['default'] if default is not None: default_source_name = default[0] default_source = None for s in sources: if s['name'] == default_source_name: default_source = s break if default_source is None: raise RuntimeError( 'No source matching "%s", referenced in default setting.', (default_source_name,) ) if isinstance(default[1], six.string_types): default_item_name = default[1] elif isinstance(default[1], list): default_item_name = 'default' source = os.path.join(settings['PATH'], default_source['url'][1:]) destination = os.path.join(s['base_path'], default_source_name, default_item_name, default_source['filename']) process_image((source, destination, default[1]), settings) # Change img src to url of default processed image. img['src'] = os.path.join(s['base_url'], default_source_name, default_item_name, default_source['filename']) # Create picture tag. picture_tag = soup.new_tag('picture') for s in sources: # Create new <source> source_attrs = {k: s[k] for k in s if k in ['media', 'sizes']} source_tag = soup.new_tag('source', **source_attrs) srcset = [] for src in s['srcset']: srcset.append("%s %s" % (os.path.join(s['base_url'], s['name'], src[0], s['filename']), src[0])) source = os.path.join(settings['PATH'], s['url'][1:]) destination = os.path.join(s['base_path'], s['name'], src[0], s['filename']) process_image((source, destination, src[1]), settings) if len(srcset) > 0: source_tag['srcset'] = ', '.join(srcset) picture_tag.append(source_tag) # Wrap img with <picture> img.wrap(picture_tag) def process_picture(soup, img, group, settings, derivative): """ Convert a simplified picture to a full HTML picture: <picture> <source class="source-1" src="image1.jpg"></source> <source class="source-2" src="image2.jpg"></source> <img class="image-process-picture" src="image3.jpg"></img> </picture> to <picture> <source srcset="...image1.jpg..." media="..." sizes="..."></source> <source srcset="...image2.jpg..."></source> <source srcset="...image3.jpg..." media="..." sizes="..."></source> <img src=".../image3.jpg"></img> </picture> """ process_dir = settings['IMAGE_PROCESS_DIR'] process = settings['IMAGE_PROCESS'][derivative] # Compile sources URL. Special source "default" uses the main # image URL. Other sources use the <source> with classes # source['name']. We also remove the <source>s from the DOM. sources = copy.deepcopy(process['sources']) for s in sources: if s['name'] == 'default': s['url'] = img['src'] source_attrs = {k: s[k] for k in s if k in ['media', 'sizes']} s['element'] = soup.new_tag('source', **source_attrs) else: s['element'] = group.find('source', class_=s['name']).extract() s['url'] = s['element']['src'] del s['element']['src'] del s['element']['class'] url_path, s['filename'] = os.path.split(s['url']) s['base_url'] = os.path.join(url_path, process_dir, derivative) s['base_path'] = os.path.join(settings['OUTPUT_PATH'], s['base_url'][1:]) # If default is not None, change default img source to the image # derivative referenced. default = process['default'] if default is not None: default_source_name = default[0] default_source = None for s in sources: if s['name'] == default_source_name: default_source = s break if default_source is None: raise RuntimeError( 'No source matching "%s", referenced in default setting.', (default_source_name,) ) if isinstance(default[1], six.string_types): default_item_name = default[1] elif isinstance(default[1], list): default_item_name = 'default' source = os.path.join(settings['PATH'], default_source['url'][1:]) destination = os.path.join(s['base_path'], default_source_name, default_item_name, default_source['filename']) process_image((source, destination, default[1]), settings) # Change img src to url of default processed image. img['src'] = os.path.join(s['base_url'], default_source_name, default_item_name, default_source['filename']) # Generate srcsets and put back <source>s in <picture>. for s in sources: srcset = [] for src in s['srcset']: srcset.append("%s %s" % (os.path.join(s['base_url'], s['name'], src[0], s['filename']), src[0])) source = os.path.join(settings['PATH'], s['url'][1:]) destination = os.path.join(s['base_path'], s['name'], src[0], s['filename']) process_image((source, destination, src[1]), settings) if len(srcset) > 0: # Append source elements to the picture in the same order # as they are found in # settings['IMAGE_PROCESS'][derivative]['sources']. s['element']['srcset'] = ', '.join(srcset) img.insert_before(s['element']) def process_image(image, settings): # Set default value for 'IMAGE_PROCESS_FORCE'. if 'IMAGE_PROCESS_FORCE' not in settings: settings['IMAGE_PROCESS_FORCE'] = False path, _ = os.path.split(image[1]) try: os.makedirs(path) except OSError as e: if e.errno == 17: # Already exists pass # If original image is older than existing derivative, skip # processing to save time, unless user explicitely forced # image generation. if (settings['IMAGE_PROCESS_FORCE'] or not os.path.exists(image[1]) or os.path.getmtime(image[0]) > os.path.getmtime(image[1])): i = Image.open(image[0]) for step in image[2]: if hasattr(step, '__call__'): i = step(i) else: elems = step.split(' ') i = basic_ops[elems[0]](i, *(elems[1:])) i.save(image[1]) def register(): signals.content_written.connect(harvest_images)