MKVShrink features explained:

* Reduce file-size of MKV video files.

Many MKV creation tools perform a full duplication process on video and audio content from disc-based media, resulting in a extremely large video file.
MKV Shrink was created to modify the video and audio portions of these MKV files to make them smaller.

It does this by offering different quality adjustment options such as the ability to transcode the video and audio using different codecs, adjustable bitrate/quality adjustments and pixel-count change by means of lowering the resolution and/or black border removal.
MKV Shrink Additional Features:

* Transcode/shrink video/audio from non-protected Bluray discs by means of mpls track detection or "disc.inf" playlist files located on the disc.

* Transcode/shrink non-protected m2ts, mts, avi, mp4 and m4v video files.
MKV Shrink Special Features:

* Drag & Drop Batch-mode conversions.

* Automatic black-border (crop) removal (only available with the MKVShrink GT upgrade)

* Full multi-core support, the faster your computer, the faster MKV Shrink works.

* Fixed quality (CRF) or Fixed bitrate (Kbps) for video compression.

* Keeps chapter/scene markings if found in original MKV file.

* Multi-audio track support, including the ability to use different settings for different streams (Multi-channel surround for the main audio track, and a lower quality stereo format for the commentary for example)

* Adjustable "Default Settings" (with a selection of commonly used presets), with the ability to customize settings for individual files (use a different resolution for one particular file for example)

* Collection of generic presets, and if you upgrade to MKVShrink GT, specific presets for 1000+ different tablets, smartphones and other devices.