I am not 100% sure about this, but I think hardware mpe is only for timeline rendering, not for exporting
Hey David -
It isn't that encoding some formats are more or less accelerated than others, but that no encoding at all is accelerated. While encoding is not accelerated, this is only one part of the export process and many other steps benefit from the Mercury Playback Engine explaining the varying GPU usage that you observe. As an example, when you transcode 1920x1080 AVCHD to 720x480 DV in your video, compressing to DV is done in software but the scale between sizes is done on the GPU. This balancing of GPU and CPU work is intentional, we do not want to completely leave the CPUs idle.
Preview renders, direct exports and queued exports through AME all use the acceleration engine. As you have noticed there are some exceptions when exporting with AME. When using queued exports, effects will always be rendered on the GPU but there are a few cases where scaling will currently be done on the CPU. This is something we hope to improve in the future.
Thanks - that was a good explanation.
I have a follow up question.
Which is faster to render out a project in Encore that I have the timelines dynamically linked to from Premiere--
Is it better to let Encore do the rendering for SD/HD projects or use AME to render via Encore and then select burn project?