When processing multiple pictures (batch) mixed in portrait and landscape. setting the target resolution on the longest side would really be helpful.
In the older version of Gigapixel V1, 2 or 3, it can resize base on the long edge but since V4 the feature has been removed.
In the older version, you can set fit to width & height, for example 6000px x 6000px, the software will keep the aspect ratio of the image and upscale it base on the long side. I don’t understand why the developer decided to remove such useful feature.
I have contacted Topaz Lab Customer services, in 2019 April. At that time, the Development Team told me that “they will re-implementing in some fashion in the future, but is currently not scheduled”.
Let’s hope re-implementation is soming soon.