Harappan Script PDF Generator 📄🏺

This Streamlit application provides a user-friendly interface to dynamically generate PDF documents from a sequence of image-based Harappan script characters. Users can input a custom string of numeric indices, and the app will compile the corresponding images into a properly formatted, downloadable PDF.

Overview

The application takes an input string formatted with underscores (e.g., _1_2_3_4) and maps each number to an image file (e.g., 1.png, 2.png) stored in a designated local folder. It dynamically calculates aspect ratios to maintain image proportions, auto-wraps "text" to the next line when it reaches the page width, and generates new pages automatically.

Features

• Dynamic PDF Generation: Compiles a sequence of images into a single PDF based on user input.
• Customizable Page Layout: Adjust maximum writable page width/height, and starting X/Y margins (in mm).
• Adjustable Character Sizing: Set the exact font width (image width) and fine-tune horizontal and vertical gaps between characters.
• Smart Wrapping: Automatically detects page boundaries to wrap characters to the next line or create a new page.
• Visual Reference: Displays a master reference grid (all_images.png) at the bottom of the app to help users identify the correct character indices.

Directory Structure

For the application to work correctly, ensure your project directory is set up as follows:

your_project_folder/
│
├── app.py                # The main Streamlit script
├── all_images.png        # (Optional) Reference image showing all characters
└── final/                # Folder containing the individual character images
    ├── 1.png
    ├── 2.png
    ├── 3.png
    └── ...

Requirements

Ensure you have Python installed along with the following dependencies. You can install them using pip:

pip install streamlit opencv-python fpdf

(Note: opencv-python provides the cv2 module used for calculating image aspect ratios).

How to Run

1. Save the provided code as app.py.
2. Ensure your final/ folder is populated with the correctly numbered .png images.
3. Open your terminal or command prompt, navigate to the project directory, and run:

streamlit run app.py

4. The application will automatically open in your default web browser.

Usage Guide

1. Configure Parameters: Use the sidebar on the left to set your desired output filename, page layout, and spacing metrics.
2. Enter Indices: In the main text area, enter your sequence of character indices. Ensure they are separated by underscores (e.g., _12_45_8_112).
3. Generate: Click the 🚀 Generate PDF button.
4. Download: Once the processing is complete, click the 📥 Download PDF button to save the generated file to your local machine.