I understand that 1080p is the max resolution supported by Cloudflare Stream. However, it seems that the limit applies to the video’s height, irrespective of the video’s aspect ratio.
In our application, we need to support the portrait format, maxing out at 1080x1920, which is commonly used in social media and well adapted to mobile users.
I understand that 1080x1920 could be wasteful for users watching in landscape mode, e.g., on a desktop computer or laptop, but at the time, the current implemented solution ends up with 32% the number of pixels, and, about 34% of the bitrate (2.6 mbps in the original portrait format and 7.3 mbps if the video is rotated by 90 degrees before uploading).
The lower quality is definitely noticeable and I don’t think it is a justified constraint. In particular, one could imagine a workaround consisting of client-side preprocessing to add EXIF video rotation before upload and later instructing the video player to rotate the footage during playback. In our case, it’s difficult to do client-side preprocessing as we are expecting users to possibly upload media from a Web browser running on a mobile phone.