Output aspect ratio 9:16 won't stick

[Whitla]

Hi there

I'm trying to export a 9:16 clip from a 16:9 video to upload to spotify to be used as a spotify canvas video loop.

My original video is 3840:2160.

I set the sequence to then export to 1215:2160 which is 9:16

When I go to export the video it gets set to 1214:2160.

I am exporting using current version of Premiere and encoder as an mp4 file using the H264 codec

If I try to change the width back to 1215 it simply reverts back to 1214.
What is going on here?

[Sami Succar]

I second that. I just tried it on my system, almost all codecs won't accept a width of 1215. Only Apple ProRes does.

[Ann Bens]

You need to use even numbers.

Choose numbers you can devide by 4.

1216 would be a better choice.

[Whitla]

Thanks very much this makes total sense.

The math that ended up making this work was as follows.

Start with 1215x2160

then divide by 5

then multiply by 4

you get 972x1728

Then change the size of the video in the sequence to 80% as you have made the size of the video 20% smaller.

[Sami Succar]

TIL A simple explanation if you're curious to know more.

[Whitla]

Thanks for this extra info!