I have about 250 MP4 files that have varying aspect rations close to 4:3 but some wider and some squished.

Normally, I open MKVMerge GUI, load the file, click the video track and set 4/3 in the "set aspect ratio" drop-down, but I'm sure I read there's a way to do batch conversions.

With 250 files, I thought I'd ask if quick/easy to do... again, just need to force it to display 4/3 and re-save the file as MKV. I watch the files in KODI which has the option to force it there as well, but, then every episode I have to tell it to do so. Seems easier to just do this.

Thanks