Mountaineer is a high quality image compression utility for Linux that batch compresses JPEG, PNG, GIF, and WebP images. It uses the best available compression libraries behind a modern interface, letting you add files or folders, tune quality settings per format, and compress in place.
- Supports JPEG, PNG, GIF, and WebP formats
- Batch compression via file dialog, Add Folder (recursive), or drag-and-drop
- In-place compression — files are overwritten directly, no renamed copies
- Configurable quality settings per format
- Lossless mode, strip metadata, and warn-before-overwrite toggles in Preferences
- Negative savings (file grew) called out in red
- Sortable, manually resizable columns
- Compression runs in a background thread — UI stays responsive during batch jobs
- Errors during compression logged to a log file.
Python >= 3.12
sudo dnf install mountaineer-1.4.0-1.fc43.x86_64.rpmThe oxipng library is not available in the Debian/Ubuntu repos for some reason. You will need to install it first.
https://github.com/oxipng/oxipng/releases
After that install Mountaineer:
sudo apt install mountaineer-1.4.0.debThe version of jpegoptim shipped in Debian and Ubuntu repositories is below 1.5.0, which means the Auto Progressive option in JPEG preferences will not be available on those systems. This is a packaging limitation and not a bug in Mountaineer.
A full user guide is available Here.
GNU AGPLv3. See the LICENSE file for details.
Mountaineer is developed using AI assistance. We take the upmost care to prevent AI 'slop' and review with Snyk and SonarQube to maintain a quality code base.