mkimage.py

#!/usr/bin/python3
# -*- coding: utf-8; mode: python -*-
__version__ = "1.0"
__date__ = "20170323"
__author__ = "kthoden@mpiwg-berlin.mpg.de"

import os
import sys
import logging
import configparser
import argparse
from PIL import Image, ImageFont, ImageDraw

logging.basicConfig(level=logging.DEBUG, format=' %(asctime)s - %(levelname)s - %(message)s')

DIMENSIONS = (2000, 2844)                 # ratio of 0.703205791106515
BACKGROUND = 0, 0, 0

METADATA_DICT = {'eoa_series': 'Studies', 'eoa_number': '125',
                 'eoa_authors': ['Klaus Thoden'], 'eoa_title':
                 'Der ewige Testband', 'eoa_subtitle':
                 'Experimentell'}

SERIES_COLOURS = {"sources" : (40, 96, 49),
                  "studies" : (13, 40, 72),
                  "proceedings" : (173, 54, 50),
                  "textbooks" : (210, 182, 35)}

def get_cover_image(image_path):
    """Choose a random landscape image from publications in this volume"""

    import random

    candidates = os.listdir(image_path)

    for image in candidates:
        tmp_image = Image.open(image_path + "/" + str(image))
        ratio = calculate_ratio(tmp_image)
        if ratio < 1:
            candidates.remove(image)

    chosen_image = random.choice(candidates)

    return chosen_image
# def get_cover_image ends here

def calculate_ratio(image_object):
    """Determine the aspect ratio of an image"""

    width, height = image_object.size

    ratio = float(width)/float(height)

    return ratio
# def calculate_ratio ends here

def resize_image(image_object, max_size, dimension):
    """Resize an image, preserve ratio.

    Takes three arguments, an image object, the maximal size and the
    dimension (width or height).

    https://stackoverflow.com/questions/273946/how-do-i-resize-an-image-using-pil-and-maintain-its-aspect-ratio
    """

    width, height = image_object.size

    if dimension == "height":
        height_percent = (max_size/float(height))
        wsize = int((float(width)*float(height_percent)))
        resized_image = image_object.resize((wsize, max_size), Image.ANTIALIAS)
    elif dimension == "width":
        width_percent = (max_size/float(width))
        hsize = int((float(height)*float(width_percent)))
        resized_image = image_object.resize((max_size, hsize), Image.ANTIALIAS)
    else:
        print("You must either specify height or width as dimension. Exiting.")
        sys.exit(0)

    return resized_image
# def resize_image ends here

def format_authors(authors_list):
    """Format the list of authors

    Input is the start and end point of the authors in a list. Return
    both a formatted string and the pure list of authors.
    """

    if len(authors_list) == 0:
        authors_as_string = ""
    if len(authors_list) == 1:
        authors_as_string = """%s""" % (authors_list[0])
    elif len(authors_list) == 2:
        authors_as_string = """%s and %s""" % (authors_list[0], authors_list[1])
    elif len(authors_list) > 2:
        authors_as_string = """%s""" % authors_list[0]
        for author in range(1, len(authors_list) - 1):
            authors_as_string += ", " + authors_list[author]
        authors_as_string += " and %s" % (authors_list[-1])

    return authors_as_string
# def format_authors ends here

def add_watermark(image, watermarkstring):
    """Add a string of text across the cover. Return a rotated image object"""

    # https://codenhagen.wordpress.com/2015/12/04/putting-rotated-text-on-images-with-pillow-python/

    base_image = Image.open(image)

    tmp_img = Image.new("RGBA", (DIMENSIONS[1], DIMENSIONS[0]), (0,0,0,0))
    font_colour = (255,0,0)
    big_red_font = ImageFont.truetype("Helvetica", 200)
    text_canvas = ImageDraw.Draw(tmp_img)

    text_canvas.text((0, 0), watermarkstring, font=big_red_font, fill=font_colour)

    slanted_image = tmp_img.rotate(60, expand=True)

    # add third parameter as transparent mask
    # https://stackoverflow.com/questions/5324647/how-to-merge-a-transparent-png-image-with-another-image-using-pil
    base_image.paste(slanted_image, (200, 100), slanted_image)

    base_image.save(image)
    print("Added a watermark to", image)
    # return slanted_image
# def add_watermark ends here

def centered(textstring, font_spec):
    """Return coordinates for a centered string."""

    # would also be good to have a function for multiline text:
    # calculate width of text
    # if too wide, split by whitespace
    # compare width of canvas and string and determine how many lines we need
    # split list of words into that many equal parts and join them
    # get length of each line for centering
    # determine lineskip
    # return result
    #
    # or try and do that using multiline:
    # https://pillow.readthedocs.io/en/3.3.x/reference/ImageDraw.html?highlight=multiline_text#PIL.ImageDraw.PIL.ImageDraw.Draw.multiline_text
    # https://github.com/python-pillow/Pillow/issues/2067
    # https://docs.python.org/3.3/library/textwrap.html?highlight=textwrap#module-textwrap


    tmp_draw = ImageDraw.Draw(Image.new("RGB", DIMENSIONS, BACKGROUND))

    string_width, string_height = tmp_draw.textsize(textstring, font=font_spec)

    coordinate = DIMENSIONS[0] / 2 - string_width / 2

    return coordinate
# def centered ends here

def create_cover(metadata_dict, image_directory, cover_filename):
    """Create a cover using PIL"""

    img = Image.new("RGB", DIMENSIONS, BACKGROUND)

    upper_part = Image.new("RGB", (DIMENSIONS[0], int(DIMENSIONS[1]/3)), SERIES_COLOURS[metadata_dict['eoa_series'].lower()])
    img.paste(upper_part, (0, 0))

    title_text = metadata_dict['eoa_title']
    subtitle_text = metadata_dict['eoa_subtitle']
    authors_text = format_authors(metadata_dict['eoa_authors'])
    series_number_text = "{0} {1}".format(metadata_dict['eoa_series'], metadata_dict['eoa_number'])

    if metadata_dict['eoa_series'].lower() == "sources":
        press_text = "Edition Open Sources"
    else:
        press_text = "Max Planck Research Library for the\nHistory and Development of Knowledge"

    if metadata_dict['eoa_series'].lower() == "textbooks":
        fill_colour_top = (0, 0, 0)
    else:
        fill_colour_top = (255, 255, 255)

    big_bold_font = ImageFont.truetype(font="Times New Roman Bold", size=120)
    medium_font = ImageFont.truetype(font="Times New Roman", size=100)
    small_font = ImageFont.truetype(font="Times New Roman", size=80)

    text_draw = ImageDraw.Draw(img)

    text_draw.text((centered(title_text, big_bold_font), 200), title_text, font=big_bold_font, fill=fill_colour_top)
    text_draw.text((centered(subtitle_text, medium_font), 350), subtitle_text, font=medium_font, fill=fill_colour_top)
    text_draw.text((centered(authors_text, small_font), int(DIMENSIONS[1]/3)-200), authors_text, font=small_font, fill=fill_colour_top)
    text_draw.text((centered(press_text, small_font), DIMENSIONS[1]-400), press_text, font=small_font)
    text_draw.text((centered(series_number_text, small_font), DIMENSIONS[1]-200), series_number_text, font=small_font)

    image_on_cover = Image.open(os.path.join(image_directory, get_cover_image(image_directory)))

    MAXIMUM_HEIGHT = 1200

    resized_image = resize_image(image_on_cover, MAXIMUM_HEIGHT, "height")

    coord = DIMENSIONS[0]/2 - resized_image.width/2
    img.paste(resized_image, (int(coord), 1200))

    img.save(cover_filename)
    print("Wrote", cover_filename)

    watermark = add_watermark(cover_filename, "Automatically generated cover.\nDo not use in production!")
# def create_cover ends here

if __name__ == '__main__':
    parser = argparse.ArgumentParser()
    parser.add_argument("image_dir", help="Path to directory with potential images.")
    parser.add_argument("-c", "--config", help="File that contains the publication data.", default="publication.cfg")
    parser.add_argument("-o", "--output", help="Name of output file.", default="Cover.jpg")
    args = parser.parse_args()

    IMAGES = args.image_dir

    if os.path.exists("publication.cfg"):
        logging.debug("Using %s as publication config" % (args.config))
        config = configparser.ConfigParser()

        config.read(args.config)

        list_of_authors = list(set(config['Authors'].values()))
        for author in list_of_authors:
            if len(author) == 0:
                list_of_authors.remove(author)

        METADATA_DICT.update({'eoa_series' : config['Technical']['Serie']})
        METADATA_DICT.update({'eoa_number' : config['Technical']['Number']})
        METADATA_DICT.update({'eoa_title' : config['Technical']['Title']})
        METADATA_DICT.update({'eoa_subtitle' : config['Technical']['Subtitle']})
        METADATA_DICT.update({'eoa_authors' : list_of_authors})
    else:
        logging.debug("Using the built-in metadata as publication config")

    OUTFILE = args.output

    create_cover(METADATA_DICT, IMAGES, OUTFILE)
# finis