I happen to have available a MacMini with M4Pro, MacBookPro with M4Max, MacBookPro M4Max (maxed out version) and MacStudio M3Ultra (28-core version).
Choosing a reference underwater image using the redefine realistic, I found the following processing times. Consider these in the relative sense,
MM M4Pro 28 min
MBP M4Max 8 min
MBP M4Max(max) 7 min
MS M3Ultra 12 min
My initial take with the Mini M4Pro versus the MBP M4Max, was that Gigapixel benefits from the 2X memory bandwidth of the Max, as well up to 2X GPU cores. Notable the Mini M4Pro spent a lot of time with no workload on the GPP or GPU cores, suggesting memory bandwidth was the limiting factor.
That said M3Ultra has a slightly lower clock speed for the GPP and GPU cores, though a far greater memory bandwidth and far more GPU cores. But at the same time finishes behind a notebook with a M4Max.
Google suggests that Gigapixel suffers from poor optimization relative to the additional resources available in the Ultra device. Perhaps but I didn’t pull up additional tools to understand if less than all of the GPU cores are in use relative to the Ultra.
On the other hand using Photo AI on the same reference image, choosing carefully the configuration for processing yielded a result that was near identical to Gigapixel but processing time was less than two seconds with the M3Ultra. This alone is a stunning result independent of all of the measurements cited above.
