Greasy Fork is available in English.
Speed control, precise aspect ratio control, nice 'n' accurate looper, volume booster, and more.
This suite of tools contains:
a speed control, with a lock to prevent tampering
play/pause lock
precise aspect ratio control, including tools to mirror and flip as well as resize the video container
a time seek function
a nice 'n' accurate looper, not limited to whole seconds
various cosmetic tweaks
a chapter mover
a volume booster
The interface is fully scalable to prevent clutter.
