Engines and licences
Kovert is the app: the window, the queue, the presets, the settings, the file handling. The work on the pixels is done by open source engines. This page lists them, what each one does and how it is licensed.
Kovert itself is closed source. Nothing on this page is.
Installed with the app
These arrive in the installer. Together they are the app.
- sharpImage pipelineShrinks a photo while it decodes rather than after, which is most of the reason a folder goes quickly.Apache-2.0
- libvipsImage engine under sharp, dynamically linkedDoes the pixel work. You can also pick it by name in settings, or leave the choice on auto.LGPL-2.1
- ElectronApp shellMIT
- React and RadixInterfaceMIT
- yauzl and yazlStreaming zip read and writeLets Kovert list a 40 GB archive without unpacking it first.MIT
- FFmpeg and FFprobeVideo, HEIC decoding, media probingHardware encoding where your machine has it, x264 and x265 in software where it does not.GPL
- ONNX RuntimeRuns the cutout and upscaling modelsDirectML on Windows, CoreML on Apple Silicon, processor fallback when a driver drops the device.MIT
Added after you install
Kovert fetches these when you turn on the feature that needs them, and you can remove them again. What you never switch on is never downloaded.
- BiRefNetBackground removal model, the precise oneAbout 970 MB. Worth it for hair and fine edges.MIT
- BEN2Background removal model, the standard oneAbout 220 MB, close to BiRefNet in quality, runs fine on 8 GB machines.MIT
- ISNetBackground removal model, the quick oneAbout 180 MB, and enough for most product shots.Apache-2.0
- Real-ESRGANUpscaling modelsThe 2× and 4× weights, and a variant tuned for drawings. Each downloads and deletes on its own.BSD-3-Clause
- OllamaHosts the vision model that renames filesKovert does not install this one. If you already run it, give Kovert the address.MIT
The FFmpeg notice
FFmpeg is GPL software. Kovert runs it as a separate process and does not link against it, and ships a build from the packagers the FFmpeg project links, not one we compiled.
If you want the exact build Kovert uses, or its source, write to info@kovert.app and you get both.
The models
The cutout and upscaling models are published weights, downloaded from the projects that host them. They run on your machine and send nothing back.