8 Replies Latest reply on Jun 15, 2010 4:43 AM by Chuck A. McIntyre

    Render Previews Size and Aspect Ratio

    Chuck A. McIntyre Level 3

      We are currently editing several projects that have an odd editing dimension but a standard output dimension.  These videos are for a live event with rows of four projection screens set somewhat tightly together.  From a production standpoint, we wanted to have content flow freely across all four screens.  We prefer not to have to visualize this, so we set up a "Desktop" mode, square pixel sequence within a project with a dimension of 2560 x 540.  The 2560 dimension is because most of the footage is from the Panasonic P2 camera (HVX200P).  This camera shoots video at a rectangular pixel dimension of 1280 x 1080.  The pixel aspect ratio is 1.5.  So 1.5 times 1280 = 1920, the final output square pixel dimension. In this case the final output WOULD be 1920 x 2 or 3840 x 540 high. 3840 divided by 4 = 960 x 540.  So we're outputting standard def widescreen to each screen.  Premiere automatically creates the final output through nesting the 2560 x 540 sequence twice in a DVCPROHD 1080i sequence of standard size.  The two 2560 x 540 sequences, one on video layer 1 and the other on video layer 2 are positioned so that the video that corresponds to screen one is positioned top-far right and the second instance of the sequence is positioned bottom far left. The final output file is an avi in the Canopus HQ codec at 1920 x 1080.  This output file is a video that is actually four standard def videos in one 1920 x 1080 video. The Grass Valley Turbo 2 outputs this standard hi-def  file to a Vista Spyder which will isolate and project the four videos-in-one, to the appropriate four screens.

       

      This type of project would not have been possible without CS5 and Mercury.  Premiere is handling this oddity extremely well.

       

      One minor issue for the support gurus:

      When we render the Desktop mode square pixel 2560 x 540 sequence timeline, we get what appears to be random, mixed render results.  Sometimes this odd shape renders perfectly, other times it renders out to small dimension that is less than half size.  Other times if renders out with pieces of the elements small. but positioned with spaces between them.  Playing around with sequence render settings and playback resolution, sometimes SEEMS to cause the render to correct itself.  Sometimes a computer restart SEEMS to correct the issue.  Any thoughts?

        • 1. Re: Render Previews Size and Aspect Ratio
          Level 4

          Chuck,

           

          Wow, that sounds very cool....nice project !  If you have time could you post a pic of what your program monitor looks like ...maybe timeline too ??

           

           

           

          Rod

          • 2. Re: Render Previews Size and Aspect Ratio
            Chuck A. McIntyre Level 3

            I'm trying moving everything to a sequence with different settings, 3840 x 540 Desktop mode with square pixels.  So far everything renders correctly, but we'll see...

            • 3. Re: Render Previews Size and Aspect Ratio
              Colin Brougham Level 6

              Chuck,

               

              What are you using for your preview codec? MPEG I-frame?

              • 4. Re: Render Previews Size and Aspect Ratio
                Chuck A. McIntyre Level 3

                "Chuck,

                 

                What are you using for your preview codec? MPEG I-frame?"

                 

                Yes, we tried some others without success.

                • 5. Re: Render Previews Size and Aspect Ratio
                  Colin Brougham Level 6

                  Good, I think that's your best shot. Other codecs seem to freak out once they get into non-standard frame sizes, and since Adobe has limited our preview codec choices since CS4, we're not left with too many other options.

                   

                  Barring previewing, are you able to export to your intermediate/final movie without problems?

                  • 6. Re: Render Previews Size and Aspect Ratio
                    Chuck A. McIntyre Level 3

                    Colin Brougham wrote:

                    Barring previewing, are you able to export to your intermediate/final movie without problems?

                     

                    The final exported video is 1920 x 1080. I have test exported in a number of formats without any problems at all.

                     

                    The 2560 x 540 version, (BEFORE it is "processed" through 2 instances of itself in a standard DVCPROHD sequence) is for editing purposes only, so we can actually see how the video will play across four projection screens.

                     

                    The remaining issue I'm trying to work out is, how to best get the finished video into the grass valley Turbo 2.  The Turbo 2 takes an AVI file transcoded into the Canopus HQ codec natively without having to transcode.  The only way to get an avi from Premiere Pro CS5 into the Canopus HQ codec is to first export the finished video as an uncompressed avi from Premiere, import it into either "Edius" or "Procoder 3" and export in the HQ codec.  The export from Premiere CS5 + Mercury takes 15 minutes.  The export (HQ encoded file) from the trial version of Edius takes around 10 minutes.  IMO grass valley should create a plug-in for Premiere CS5 and shouldn't allow the quickest export to be Canopus exclusive.  I seriously doubt many Premiere CS5 users will switching to Edius any time soon.

                     

                    According to grass valley, the Turbo 2 will accept an MPEG-2 Pgm Stream, whatever the heck a Pgm Stream is???.  I did a Google search without success.  Of course Premiere will export an MPEG-2 file, but how the Pgm Stream relates to this, I have no idea. There are a mind boggling array of settings and the preset seems to export a rather compressed looking video.

                     

                    My current thinking is to try to convince the boss to buy Procoder 3.

                     

                    BTW:

                    the 3840 x 540 version sequence renders fine part of the time and then for whatever reason starts creating a preview that is about 35% of the correct dimension... So back to the original Sequence settings of 2560 x 540

                    • 7. Re: Render Previews Size and Aspect Ratio
                      Chuck A. McIntyre Level 3

                      Render files, for the 2560 x 540 and 3840 x 540  are not available after the project is closed and re-opened.  The render area reverts back to yellow and requires re-rendering.

                       

                      Related to the small dimension render files... sometimes when you go to "Sequence Settings" - "Video Previews" and hit the "Reset" button, Premiere will render the timeline at the correct preview size as opposed to the 30% size..

                       

                      BTW, I have all of the Premiere CS5 updates installed as well as the very latest Nvidia drivers.

                      • 8. Re: Render Previews Size and Aspect Ratio
                        Chuck A. McIntyre Level 3

                        It seems that If I go to "Sequence Settings" - "Video Previews" and hit the "Reset" button, after opening a 2560 x 540 project, Premiere will render the timeline at the correct preview size consistently on all four of our editing machines ranging from laptop to Mercury to non Mercury configurations.

                        After hitting the reset button, the following dialog pops up most of the time:

                         

                        *Also, When I render a 2560 x 540 sequence and close the project, the render files are lost when I reopen the project. Unless I'm missing something, It's a minor bug with a minor workaround that should be looked at by Adobe and fixed in the next Premiere update.

                         

                         

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