24 Replies Latest reply on Dec 27, 2011 12:35 PM by shooternz

    Strange problem with aspect ratios.....

    neil wilkes Adobe Community Professional & MVP

      Here's the problem.

      Source file is from After Effects 9 and is PAL, 25fps, 1024x576 Square Pixel, Progressive Scan.

      Trying to get this anamorphic.

      However, the size changes! It gets narrower, and there is a definite pillarboxing to left & right of the output.

      Why? What have I got wrong? Please see screen grabs below.

       

      The project is created as a custom one, 1024x576/25 PS as trying to use DV Widescreen gives the same pillarboxing.

      Surely 1024x576 is correct?

      source.png

       

      output.png

        • 1. Re: Strange problem with aspect ratios.....
          neil wilkes Adobe Community Professional & MVP

          Addendum.

           

          I see that this is changed now - http://blogs.adobe.com/toddkopriva/2009/07/pixel-aspect-ratios-in-after-e.html

          However, this is causing me enormous issues as the resulting image is simply not the same size - switch from shot to shot & see what I mean.

          I do not think that the Animator will go for this in a big way.......

          Okay, I can always use CS3 Premiere to take the 1024x576 files - but all the editors I work with use 1024x576, not 1050x576.

          • 2. Re: Strange problem with aspect ratios.....
            Jim_Simon Level 8

            I can suggest two things.  Only use earlier versions of Adobe software which all use the old PAR.

             

            Or, only use newer versions of Adobe software which all use the new PAR, and adjust accordingly.

            1 person found this helpful
            • 3. Re: Strange problem with aspect ratios.....
              neil wilkes Adobe Community Professional & MVP

              Thanks, Jim.

              That is the conclusion I have reluctantly come to.

              It is a bit odd though, having to dig up an old CS3 version of Premiere Pro.

              Wonder why this is not a setting in the newer versions?

              The difference really is quite substantial, and the AE animator is definitely using AE9 - isn't that CS4?

              • 4. Re: Strange problem with aspect ratios.....
                Jim_Simon Level 8

                Probably.  CS5 is version 10.

                 

                Of course, I'd recommend you both upgrade to CS 5.5, which has some very nice improvements over the versions you're both using.

                • 5. Re: Strange problem with aspect ratios.....
                  Ann Bens Adobe Community Professional & MVP

                  From CS4 up 1024x576 has changed to 1050x576 for PAL widescreen square pixels due to the PAR.

                  Screendump shows blue shape 1024x576. Red unlying shape is 1050x576. All this in AE 5.5

                   

                  1050.png

                  • 6. Re: Strange problem with aspect ratios.....
                    Stan Jones Adobe Community Professional & MVP

                    The animator, working in AE9 (which is CS4) has to work at it a bit not to use the CS4/CS5 standard pars.

                     

                    But AE did have ways to change the default behavior. This is one of the links from Todd's blog you linked above. I wonder if the animator is doing this?

                     

                    http://provideocoalition.com/index.php/cmg_blogs/story/make_it_go_away/

                    • 7. Re: Strange problem with aspect ratios.....
                      neil wilkes Adobe Community Professional & MVP

                      Many thanks to all for the assistance.

                      I have no idea what the animator is doing, as I cannot even get him to provide an anamorphic image (apparently it always comes out wrong and now I know why).

                      I am stuck with this at 1024x576.

                      What I do not understand is how both Aspect Ratios can be the same when one is 26 pixels wider than the original one.

                      Surely this means that somewhere a circle is not going to be circular? If 1024x576 in Square Pixels gives me a circle - and it does - how can 1050x576 also provide a circle?

                       

                      Then again, I am but a sound engineer and as the whole world knows, we are apparently at the bottom of the food chain anyway ( )

                      • 8. Re: Strange problem with aspect ratios.....
                        neil wilkes Adobe Community Professional & MVP

                        Sorry, but this is making no sense to me at all.

                        Maybe I am missing something here, but how on earth can 1050x576 be a 16:9 Square Pixel aspect ratio?

                        Look at the maths of the thing:

                        576/9 = 64.

                        64*16 = 1024, not 1050.

                        1050/16 = 65.625

                        65.625*9 = 590.625

                        How can 1050x576 in square pixels possibly be a 16:9 aspect ratio?

                         

                        Likewise, the 4:3 version makes no sense either.

                        788x576 cannot be 4:3 in square pixels as again, we do the maths and find that

                        576/3 = 192

                        192*4 = 768, not 788.

                         

                        To my mind, there has to be automatic scaling going on somewhere here, which means that what gets designed is not what is output.

                        It cannot be, or else we would be dealing with ellipses and not circles.

                         

                        Very, very confused.

                        • 9. Re: Strange problem with aspect ratios.....
                          Stan Jones Adobe Community Professional & MVP

                          Chris Meyers' piece is the only thing that ever really helped me understand just the question you are posing. I get the notion, but following the logic through every step is another matter.

                           

                          http://provideocoalition.com/index.php/cmg_keyframes/story/par_for_the_course/

                          Then again, I am but a sound engineer and as the whole world knows, we are apparently at the bottom of the food chain anyway ( )

                          Made me laugh!

                          • 10. Re: Strange problem with aspect ratios.....
                            neil wilkes Adobe Community Professional & MVP

                            Ah - our old friend overscan.

                            This is starting to smell like an attempt to eliminate overscanning with the talk of clean aperture & production aperture.

                            Trouble is, TV systems still overscan, so the problem is not going to go away any time soon.......and we allow for this anyway.

                            The part on page 3 makes me smile too -

                            PAL 16:9

                            Here’s some more familiar numbers: 576 x (16/9) = 1024, which yields a 1024x576 square pixel image - a size many used for widescreen PAL production. (Just checking our math, 702.9 x (118/91) = 1024 which proves those weird numbers actually work.) The difference is, pre-CS4 we were jamming this correct Clean Aperture size into a Production Aperture composition, resulting in pixels unintentionally getting cut off downstream.

                            so we are getting rid of issues in one dimension to create them in another one instead!

                            Madness.

                            Even at the BBC, the techs there are still using 1024x576, and not 1050x576 as 1054x576 just is not 16:9.

                            (BTW - that link to the BBC gets you nowhere relevant either: You get redorected to http://www.bbc.co.uk/commissioning/tv/production/branding-guidelines-and-logos/ instead)

                            All I can actually find about SD delivery requirements is this:

                             

                            Format

                            The preferred format, unless otherwise advised by your Business Affairs Manager, is:

                            • DV25 compliant MOV
                            • Container format: .mov
                            • Video:

                            Bit rate / Quality: 100%
                            Codec: Quicktime DV
                            Frame size: 720x576 (16:9 or 4:3)
                            Frames per second: 25 (interlaced or progressive scan)

                             

                            which says absolutely nothing at all about Square Pixels.........

                            • 11. Re: Strange problem with aspect ratios.....
                              Jim_Simon Level 8

                              It is quite a mess, isn't it?

                              • 12. Re: Strange problem with aspect ratios.....
                                neil wilkes Adobe Community Professional & MVP

                                Jim Simon wrote:

                                 

                                It is quite a mess, isn't it?

                                That's an understatement, my friend.

                                I talked to a friend at the BBC in POst Production about this last night, and asked him "what do you use for PAL Widescreen"?

                                He said "`1024x576 Square Pixel every time - why"?

                                I told him, and the exact words were "that sounds like an AE thing as FCP does not do this".

                                Further, Apple's Compressor accepts 1024x576 SP with no chopping off, no rescaling, no black bars, it just works.

                                Apparently.

                                They do not think about PAR - they work in Square Pixels at the supposed "wrong" figures at the BBC.

                                So I do not know where this has been derived from, but it is causing me terrible headaches.

                                 

                                Very frustrating.

                                • 13. Re: Strange problem with aspect ratios.....
                                  Jim_Simon Level 8

                                  They don't broadcast square pixels, though, do they?

                                   

                                  The better question would be to ask him what PAR value they use for widescreen broadcasts.  (Assuming they still broadcast anything in SD.)

                                  • 14. Re: Strange problem with aspect ratios.....
                                    neil wilkes Adobe Community Professional & MVP

                                    Most of the BBC's output is still in SD, sad to say. HD has not got the penetration you would think yet, and it's not going to happen any time soon either.

                                    The BBC's funding is a disaster area (although this is a whole different thread) as they seem to think that saving costs is all about firing the actual program makers & people who do the work whilst keeping as much middle & upper management as possible on hundreds of thousands of pounds a year.

                                    We have a great paper called "Private Eye" who keep an eye on this stuff, and sadly it is all true.

                                     

                                    Getting back on topic though, as I posted earlier the SD specs state simply 720x576 for PAL.

                                    As to the PAR, who can say - they get it wrong more often than they get it right anyway. Just watch a BBC News programme and you will see what I mean.

                                    Everything that can be screwed up generally gets screwed up ("Breakfast" is a prime example of shoddy output)

                                    I suspect it changes from programme to programme.

                                     

                                    Besides, I am not talking about broadcast here but DVD, which is what it is and should simply not get changed.

                                    If Adobe want to do this sort of thing for Broadcast then that is right and proper, but it should be an option, not a mandatory thing.

                                    My problem still remains - 1024x576 content simply comes out wrong now from Premiere & AE, and it should not.

                                    Quite simply, 1024x576 is Square Pixel Widescreen at 16:9, not 1050x576. I can feed my CCE-SP3 1.3.0.1 (latest & greatest build) a 1024x576 SP file and it gets it perfectly right.

                                    I cannot but help wonder what happens on a DVD player when 1050x576 source files are encoded to this odd new PAR.

                                    I also wonder what CCE-SP3 will make of it..........

                                    • 15. Re: Strange problem with aspect ratios.....
                                      Jim_Simon Level 8

                                      I cannot but help wonder what happens on a DVD player when 1050x576 source files are encoded to this odd new PAR.

                                       

                                      You get little black bars on the sides.  (Mostly covered by overscan though, so I don't worry too much about it myself.)

                                      • 16. Re: Strange problem with aspect ratios.....
                                        Ann Bens Adobe Community Professional & MVP

                                        For PAL you can crop off 14 and 12 pixels of the top and bottom in the export settings, this will get rid of the bars.

                                        The bars is in fact the empty background that portraits as black.

                                        • 17. Re: Strange problem with aspect ratios.....
                                          neil wilkes Adobe Community Professional & MVP

                                          Ann Bens wrote:

                                           

                                          For PAL you can crop off 14 and 12 pixels of the top and bottom in the export settings, this will get rid of the bars.

                                          The bars is in fact the empty background that portraits as black.

                                          This is exactly my entire point! Thanks for making it, Anne.

                                          Cropping stuff off in AME = Scaling.....which means an extra layer of processing on a file that simply should be left well alone as it throws all the careful Post Production out of the window.

                                          Sorry to bang on about this but I honestly think we need to have DVD authors considered as well as broadcast folks - most of whom are still working at 1024x576 anyway.

                                           

                                          Why can we not have the "old" way as an option?

                                          • 18. Re: Strange problem with aspect ratios.....
                                            Jim_Simon Level 8

                                            I don't disagree with your point here, but out of curiosity, why work with square pixels in the first place?  Neither broadcast nor DVD can deliver them.  Why not just work with 720 x 576 with the new PAR from the start?

                                            • 19. Re: Strange problem with aspect ratios.....
                                              neil wilkes Adobe Community Professional & MVP

                                              It's not me - it is the Post people who use FCP/Mac that use 1024x576 Square Pixels.

                                              Almost all footage I get sent is in square pixels......

                                              Also, FWIW, I wrote to Cinemacraft about this, and they say categorically that 1024x576 Square Pixels is correct - not 1050x576.

                                              • 20. Re: Strange problem with aspect ratios.....
                                                Jim_Simon Level 8

                                                it is the Post people who use FCP/Mac

                                                 

                                                'Nuff said.

                                                 

                                                <grumble>Stupid Mac users ruining things for everyone,  Boy I'd like to ...</grumble>

                                                • 21. Re: Strange problem with aspect ratios.....
                                                  Jim_Simon Level 8

                                                  they say categorically that 1024x576 Square Pixels is correct - not 1050x576.

                                                   

                                                  Well, that rather depends on the PAR used in the deliverable.  As there is more than one viable PAR option, there can't be one categorically correct square pixel equivalent.

                                                  • 22. Re: Strange problem with aspect ratios.....
                                                    neil wilkes Adobe Community Professional & MVP

                                                    Jim Simon wrote:

                                                     

                                                    they say categorically that 1024x576 Square Pixels is correct - not 1050x576.

                                                     

                                                    Well, that rather depends on the PAR used in the deliverable.  As there is more than one viable PAR option, there can't be one categorically correct square pixel equivalent.

                                                    Say that again with a straight face, I dare you!!!

                                                     

                                                    Seriously, Jim, Square Pixels are - well, square - not rectangular, so PAR does not come into it as it will by definition be 1:1.

                                                    PAR only aplies to DVD and broadcast (SD only), and nothing else.

                                                    Adobe have altered all PAR to suit broadcast specs, and are treating DVD as the shabby old relative who sits there farting in the corner being embarrassing

                                                    • 23. Re: Strange problem with aspect ratios.....
                                                      Jim_Simon Level 8

                                                      PAR only aplies to DVD and broadcast (SD only)

                                                       

                                                      Granted.  But the PAR used for those will define the needed square pixel equivalent.  As there is more than one viable PAR, there will also be more than one square pixel standard.

                                                      • 24. Re: Strange problem with aspect ratios.....
                                                        shooternz Level 6

                                                        @Neil

                                                         

                                                        What purpose are you making this for?

                                                         

                                                        ie. Is this intended for broacast as FHA? ( Full Height Anamorphic)

                                                         

                                                        FHA is the way broadcasters, broadcast 16:9  from an  SD source.

                                                         

                                                        Workflow :

                                                        1. I deliver an HD 1080p Master file  to my facilty. 

                                                        2.They use a Kona Card to make it anamorphic SD (PAL). This becomes the Broadcast Master which is further processed as mpegs for broadcast dubbs.

                                                         

                                                        Scroll down toTelevision...

                                                        http://en.wikipedia.org/wiki/Anamorphic_widescreen

                                                         

                                                         

                                                        With pictures to illustrate.

                                                        http://media.rtl.nl/media/service/rtlnederland/adverteren/televisie/Home/Addendum%20UK.pdf