In other words: By default, don’t distort the content!
Let’s say I have defined my output to be a standard 16:9 aspect ratio. Whatever I put in should have this aspect radio in the end. Currently, any content of a different aspect ratio would be stretched to fit the frame. I would like to see letterboxes or pillarboxes instead.
Today, I could apply a filter to zoom the image accordingly, but that’s not what I am aiming for. I’m good with additional black, but I don’t want to change my actual content.
I noticed i.e., encoding.com and Amazon Elemental Media Convert offers this behavior already.