X-Git-Url: https://git.mdrn.pl/librarian.git/blobdiff_plain/0cefa871f6f1253be544a39c51e1f66f536805ce..13480b3da2d3da87f1d99c6d340c1553ca9d89c1:/librarian/formats/cover/__init__.py diff --git a/librarian/formats/cover/__init__.py b/librarian/formats/cover/__init__.py new file mode 100644 index 0000000..7a787e8 --- /dev/null +++ b/librarian/formats/cover/__init__.py @@ -0,0 +1,219 @@ +# -*- coding: utf-8 -*- +# +# This file is part of Librarian, licensed under GNU Affero GPLv3 or later. +# Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information. +# +import re +from PIL import Image, ImageFont, ImageDraw, ImageFilter, ImageEnhance +from StringIO import StringIO +from librarian import DCNS, URLOpener +from librarian.output import OutputFile +from librarian.utils import get_resource +from librarian.formats import Format + + +class Metric(object): + """Gets metrics from an object, scaling it by a factor.""" + def __init__(self, obj, scale): + self._obj = obj + self._scale = float(scale) + + def __getattr__(self, name): + src = getattr(self._obj, name) + if src and self._scale: + src = type(src)(self._scale * src) + return src + + +class TextBox(object): + """Creates an Image with a series of centered strings.""" + + SHADOW_X = 3 + SHADOW_Y = 3 + SHADOW_BLUR = 3 + + def __init__(self, max_width, max_height, padding_x=None, padding_y=None): + if padding_x is None: + padding_x = self.SHADOW_X + self.SHADOW_BLUR + if padding_y is None: + padding_y = self.SHADOW_Y + self.SHADOW_BLUR + + self.max_width = max_width + self.max_text_width = max_width - 2 * padding_x + self.padding_y = padding_y + self.height = padding_y + self.img = Image.new('RGBA', (max_width, max_height)) + self.draw = ImageDraw.Draw(self.img) + self.shadow_img = None + self.shadow_draw = None + + def skip(self, height): + """Skips some vertical space.""" + self.height += height + + def text(self, text, color='#000', font=None, line_height=20, + shadow_color=None): + """Writes some centered text.""" + text = re.sub(r'\s+', ' ', text) + if shadow_color: + if not self.shadow_img: + self.shadow_img = Image.new('RGBA', self.img.size) + self.shadow_draw = ImageDraw.Draw(self.shadow_img) + while text: + line = text + line_width = self.draw.textsize(line, font=font)[0] + while line_width > self.max_text_width: + parts = line.rsplit(' ', 1) + if len(parts) == 1: + line_width = self.max_text_width + break + line = parts[0] + line_width = self.draw.textsize(line, font=font)[0] + line = line.strip() + ' ' + + pos_x = (self.max_width - line_width) / 2 + + if shadow_color: + self.shadow_draw.text( + (pos_x + self.SHADOW_X, self.height + self.SHADOW_Y), + line, font=font, fill=shadow_color + ) + + self.draw.text((pos_x, self.height), line, font=font, fill=color) + self.height += line_height + # go to next line + text = text[len(line):] + + def image(self): + """Creates the actual Image object.""" + image = Image.new('RGBA', (self.max_width, + self.height + self.padding_y)) + if self.shadow_img: + shadow = self.shadow_img.filter(ImageFilter.BLUR) + image.paste(shadow, (0, 0), shadow) + image.paste(self.img, (0, 0), self.img) + else: + image.paste(self.img, (0, 0)) + return image + + +class Cover(Format): + """Base class for cover images generator.""" + format_name = u"cover image" + + width = 600 + height = 800 + background_color = '#fff' + background_img = None + + author_top = 100 + author_margin_left = 20 + author_margin_right = 20 + author_lineskip = 40 + author_color = '#000' + author_shadow = None + author_font_ttf = get_resource('fonts/DejaVuSerif.ttf') + author_font_size = 30 + + title_top = 100 + title_margin_left = 20 + title_margin_right = 20 + title_lineskip = 54 + title_color = '#000' + title_shadow = None + title_font_ttf = get_resource('fonts/DejaVuSerif.ttf') + title_font_size = 40 + + logo_bottom = None + logo_width = None + uses_dc_cover = False + + format = 'JPEG' + scale = 1 + + exts = { + 'JPEG': 'jpg', + 'PNG': 'png', + } + + mime_types = { + 'JPEG': 'image/jpeg', + 'PNG': 'image/png', + } + + def __init__(self, doc, format=None, width=None, height=None): + self.author = ", ".join(auth for auth in doc.meta.get(DCNS('creator'))) + self.title = doc.meta.title() + if format is not None: + self.format = format + scale = max(float(width or 0) / self.width, float(height or 0) / self.height) + if scale: + self.scale = scale + + def pretty_author(self): + """Allows for decorating author's name.""" + return self.author + + def pretty_title(self): + """Allows for decorating title.""" + return self.title + + def image(self): + metr = Metric(self, self.scale) + img = Image.new('RGB', (metr.width, metr.height), self.background_color) + + if self.background_img: + background = Image.open(self.background_img) + img.paste(background, None, background) + del background + + # WL logo + if metr.logo_width: + logo = Image.open(get_resource('res/wl-logo.png')) + logo = logo.resize((metr.logo_width, logo.size[1] * metr.logo_width / logo.size[0])) + img.paste(logo, ((metr.width - metr.logo_width) / 2, img.size[1] - logo.size[1] - metr.logo_bottom)) + + top = metr.author_top + tbox = TextBox( + metr.width - metr.author_margin_left - metr.author_margin_right, + metr.height - top, + ) + + author_font = ImageFont.truetype( + self.author_font_ttf, metr.author_font_size) + tbox.text(self.pretty_author(), self.author_color, author_font, + metr.author_lineskip, self.author_shadow) + text_img = tbox.image() + img.paste(text_img, (metr.author_margin_left, top), text_img) + + top += text_img.size[1] + metr.title_top + tbox = TextBox( + metr.width - metr.title_margin_left - metr.title_margin_right, + metr.height - top, + ) + title_font = ImageFont.truetype( + self.title_font_ttf, metr.title_font_size) + tbox.text(self.pretty_title(), self.title_color, title_font, + metr.title_lineskip, self.title_shadow) + text_img = tbox.image() + img.paste(text_img, (metr.title_margin_left, top), text_img) + + return img + imgstr = StringIO() + img.save(imgstr, format=self.format, quality=95) + OutputFile.from_string(imgstr.getvalue()) + + def mime_type(self): + return self.mime_types[self.format] + + @property + def format_ext(self): + return self.exts[self.format] + + def save(self, *args, **kwargs): + return self.image().save(format=self.format, quality=95, *args, **kwargs) + + def build(self, *args, **kwargs): + imgstr = StringIO() + self.save(imgstr, *args, **kwargs) + return OutputFile.from_string(imgstr.getvalue())