QCT Tools

Tools for working with Quick Chart File (.QCT) maps in Java

Motivation

This project was inspired by the desire to convert a few of Ordnance Survey UK maps that I have from the proprietary .qct format into more widely accessible formats for use in image viewers and GIS software. It provides an efficient Java implementation of the Quick Chart (.QCT) File Format Specification (v1.03).

A small sample of a .png file exported from a .qct file, depicting the famous Ben Nevis, the highest point in the UK. All map rights reserved by Ordnance Survey.

Features

• Decoding
  • Huffman-Coded tiles
  • Run-Length-Encoded (RLE) tiles
  • Pixel-Packed tiles
    • Note: Not implemented, as I have yet to come across any .qct file with Pixel-Packed tiles. Feel free to open an issue with a sample .qct file for implementation and testing purposes.
• Encoding
  • Run-Length-Encoded (RLE) tiles
  • Huffman-Coded tiles
  • Pixel-Packed tiles
    • Note: Not implemented, as I have yet to come across any .qct file with Pixel-Packed tiles. Feel free to open an issue with a sample .qct file for implementation and testing purposes.

Acknowledgements

This project would not be possible without the incredible work of Craig Shelley and Mark Bryant on the Quick Chart (.QCT) File Format Specification v1.03.