This is a script for mpv which automatically crops the video if the Matroska PixelCrop properties are set.

NOTE: Cropping does not work with hardware decoding. By default this script is only active when hardware decoding is disabled. See Dynamic control of hardware decoding for a workaround.

The only dependency is mkvmerge from mkvtoolnix.

Copy matroska_crop.lua into the scripts directory in your mpv config directory (defaults to ~/.config/mpv/ on Linux). If the directory doesn’t exist, create it.

If you want to add the PixelCrop metadata to already existing Matroska files you can use the mkvpropedit tool (included in mkvtoolnix):

mkvpropedit video.mkv --edit track:v1 --set pixel-crop-top=120 --set pixel-crop-bottom=120

For further information please consult the man page of mkvpropedit and the output of mkvpropedit -l.

Since cropping is not available with hardware decoding, this script can be configured to only be active if a crop is defined in the media file.

For this behaviour to be active, create the file matroska_crop.conf in the script-opts directory in your mpv config directory and add the following contents:

dynamic_hwdec=yes

Please not the absence of spaces around the equal sign.

• It cannot crop the video while using hardware decoding (limitation of mpv)
• It only works for local files (limitation of mkvmerge)
  This could be solved by mpv exposing the needed matroska metadata
• Custom filters are not applied when the video has PixelCrop metadata (disable this script temporarily when you need to use custom filters).