Flash Book Generator

flashbook.py

#!/usr/bin/env python3

# This script generates a simple PDF "flash book" (such as one through which
# you might browse at a tattoo parlor) from a folder of SVG files. Each item is
# on a separate page, with its file name written beneath. This makes it easy to
# re-create the flash book whenever SVGs are added, deleted, or renamed. 
#
# NOTES AND RECOMMENDATIONS:
#
# - `flashbook.py` must be executable. If it is not, you may need to use
#   Python to run the script with: `python3 flashbook.py`.
# - The `requirements.txt` file is a list of the Python libraries you will need
#   to run the script. You can use venv to create a virtual environment, and
#   then install these with `pip install -r requirements.txt`.
# - For best results when printing the PDF, use double-sided printing (if you
#   have it), and most PDF readers (such as Acrobat or Preview.app) will also
#   let you print multiple pages per sheet of paper. These can help cut waste.
#
# INSTRUCTIONS:
#
# You may either run `flashbook.py` from any terminal, in which case it will
# prompt you, or you may script its usage with
#
#   `flashbook.py input_folder output_file.pdf`
#
# COPYRIGHT AND LICENSE:
#
# Copyright © 2023 by Rob Dumas.
#
# This program is licensed under the GNU General Public License, version 3.
# Your use of it constitutes acceptance of the terms of said license. For the
# full text, visit https://www.gnu.org/licenses/gpl-3.0.en.html

import os, sys
from reportlab.graphics import renderPDF
from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import letter
from svglib.svglib import svg2rlg

def create_pdf_from_svgs(folder, output_pdf):
    # Scan the folder for SVGs
    svg_files = [f for f in os.listdir(folder) if f.endswith('.svg')]
    svg_files.sort()  # Sort alphabetically

    # Prepare the PDF canvas
    pdf_file = os.path.join(folder, output_pdf)
    c = canvas.Canvas(pdf_file, pagesize=letter)
    c.setAuthor("Rob Dumas")
    c.setCreator("Python 3 and ReportLab")
    c.setSubject("Flash book generator for SVGs")
    c.setTitle("Elk Lab SVG Flash Book")

    width, height = letter # 612.0 x 792.0
    max_dim = round(width * 0.75, 0)

    for index, svg_file in enumerate(svg_files, start=1):
        # Convert SVG to a format that reportlab can understand
        drawing = svg2rlg(os.path.join(folder, svg_file))
        scaleFactorX = max_dim / drawing.width
        scaleFactorY = max_dim / drawing.height
        scaleFactor = min(scaleFactorX, scaleFactorY)
        drawing.width, drawing.height = drawing.minWidth() * scaleFactor, drawing.height * scaleFactor
        drawing.scale(scaleFactor, scaleFactor)

        # Position the drawing in the middle of the page
        drawing_x_pos = (width - drawing.width) / 2
        drawing_y_pos = (height - drawing.height) / 2
        
        # Add filename to bottom of page
        c.setFont("Helvetica", 30)
        c.drawCentredString(width / 2, 50, svg_file)
        
        # Draw the SVG
        renderPDF.draw(drawing, c, drawing_x_pos, drawing_y_pos)

        # Move to the next page
        c.showPage()

    c.save()

if __name__ == '__main__':
    if len(sys.argv) != 3:
        print("Scriptable usage: flashbook.py input_folder output_file.pdf")
        input_folder = input("Enter the path to the folder containing SVG files: ")
        output_pdf = input("Enter the PDF file to generate: ")
        create_pdf_from_svgs(input_folder, output_pdf)
        print(f"PDF generated and saved as '{output_pdf}'")
    else:
        input_folder = sys.argv[1]
        output_pdf = sys.argv[2]
        create_pdf_from_svgs(input_folder, output_pdf)
        print(f"PDF generated and saved as '{output_pdf}'")

requirements.txt

wheel
setuptools
reportlab
svglib