5 Replies Latest reply on May 13, 2013 12:26 PM by Harm Millaard

    Scaling order of operations for export

    Nathan B. Level 1

      The first question I have is pretty basic, so hopefully it's an easy one to answer.

       

      I'm editing some HD footage that will be ending up on DVD, and may end up having to scale/crop certain shots to compensate for framing problems. Of course, if the output medium is SD, there's a fair bit of room to work with; but how does Premiere handle scaling within the sequence when the output will be scaled to a lower resolution? Will it scale up past 100%, and then back down to the final resolution, or intelligently determine that the output only has to be scaled down (albeit not as much)?

       

      If it's the former, I assume I'll drop things into an SD sequence to give myself the extra scaling room. If it's the latter, is there some other compelling reason to drop everything into an SD sequence before export anyway?

       

      Thanks,

      Nathanael

        • 1. Re: Scaling order of operations for export
          Jim_Simon Level 8

          Edit in a sequence matching your footage.  When it's time, export using an MPEG2-DVD preset.

          • 2. Re: Scaling order of operations for export
            Nathan B. Level 1

            Thanks. Glad I don't have to worry about any extra steps.

            • 3. Re: Scaling order of operations for export
              Harm Millaard Level 7

              One thing to keep in mind: Scaling is hardware accelerated if you have a proper CUDA enabled video card, so it is much faster and the scaling quality is better than when using an AMD card.

              • 4. Re: Scaling order of operations for export
                Nathan B. Level 1

                Even with Maximum Render Quality enabled, is non-CUDA scaling going to be inferior to CUDA scaling? In Todd's article, he mentioned that "To have results match between CPU rendering and GPU rendering, enable Maximum Render Quality." If he's still referencing scaling at that point in the article, is "match" too strong of a word?

                 

                And as far as AMD cards, isn't that changing with support for OpenCL in CS6 and CC?

                • 5. Re: Scaling order of operations for export
                  Harm Millaard Level 7

                  1. A HD clip in a SD timeline with scale-to-framesize and accelerated 3-way effect
                   
                    CPU: Gaussian low-pass sampled with bilinear
                    CPU MRQ: Variable-radius bicubic
                    GPU: Lanczos 2 low-pass sampled with bicubic
                    GPU MRQ: Lanczos 2 low-pass sampled with bicubic
                   
                    In this case the MRQ setting will only affect CPU based renders.
                    
                    2. A HD clip in a SD timeline with scale-to-framesize and a non-accelerated twirl effect
                   
                    CPU: Gaussian low-pass sampled with bilinear
                    CPU MRQ: Variable-radius bicubic
                    GPU: Gaussian low-pass sampled with bilinear
                    GPU MRQ: Variable-radius bicubic
                   
                    Because scale-to-framesize happens before effects and there is a non-accelerated effect, here the scaling will be done in software during a GPU render. During a GPU render the MRQ setting will thus apply to any software rendering done as part of the GPU render, determined on a segment-by-segment basis.
                   
                    Software's variable radius bicubic and GPU's Lanczos2 + bicubic will be pretty comparable. For more detail on the scaling used see here:
                   
                    http://blogs.adobe.com/premierepro/2010/10/scaling-in-premiere-pro-cs5.html

                   

                  There will be no change in CS6. There may be a change in CC according to Adobe Marketing, but that means you have to believe Marketing (they have claimed so much in the past, that the blind said: "I have to see it before I believe it") and it requires transferring to CC and sell your soul to Adobe.