ql-win/exiv2

Exiv2 is a tool that lets you read, write, and modify the hidden metadata embedded inside image files. Every time you take a photo with a camera or phone, invisible text tags are saved alongside the picture, things like the date, camera model, GPS location, and copyright information. This project provides both a command-line program for everyday users to view or strip this data, and a developer library for programmers who want to build apps that manage photo information. The tool works by parsing several common metadata standards: Exif (camera-specific data like lens settings and GPS), IPTC (photojournalism tags like captions and keywords), XMP (Adobe's modern labeling system), and ICC (color profile information). You can point the command-line program at an image file to print out all its hidden tags, or use it to add, change, or delete specific entries. Developers can integrate the library directly into their own C++ applications to handle metadata automatically, without building that capability from scratch. Anyone who works with large collections of photos could benefit from this. A photographer might use it to batch-remove GPS coordinates before sharing images online, protecting their privacy. A photo-sharing startup could embed the library into their app to automatically extract camera settings and display them alongside user uploads. A news organization might use it to ensure every photo has the proper copyright and caption metadata attached before publication. The project is built in C++ and runs across Windows, macOS, and Linux. It relies on a build system called CMake to compile, and can optionally pull in a few external libraries for features like PNG support or text translation. One notable design choice is that support for newer image formats like HEIF and JPEG XL is disabled by default, meaning users who need to handle those modern formats have to explicitly enable that feature during setup. The project is open source under the GPLv2 license.