For those who may not be familiar, MKV (Matroska) is a popular video container format that can hold multiple audio, video, and subtitle tracks. An MKV 300 index file is a specific type of file that contains metadata about the video content, including chapter markers, titles, and timestamps. This file is essential for navigating and playing MKV files smoothly.

mkvpropedit input.mkv --add-chapters-from=chapters.xml