REsizing

[Alwyn]

You can save a step by remuxing using ImagoMPEG-Muxer. That's how I'd do it.

Excellent, that worked a treat.

I've edited my previous post.

[Alwyn]

It's a case of googling all the terms like MUX etc.

Agree, it's a bit of a head-spin initially and I still don't fully understand it myself.

"Demux" = demultiplex/split/demerge a file into it's video component and it's audio component. You end up with a video-only file eg an m2v, and an audio-only file eg an mp2.

"Mux" = Multiplex/join/merge the video and audio files back together again.

Clicked Change VideoDAR and seen aspect ratio was already on 16:9.

Then click the green "Change DAR" button on the left. You'll then get a progress bar and a red Abort button.