11 Replies Latest reply on Feb 7, 2011 3:43 AM by Castor_uk

    Export Settings for Web/PC from PAL

    Castor_uk Level 1

       

      Hi

       

      I primarily work in producing video for playback on a PC or Web; usually from PAL SD and Widescreen.

       

      Therefore I mostly try to export to Progressive 4:3 standards but crop the source to 4:3 so that I can resize the video to standard ‘square’ dimensions (320x240, 480x360, etc).

       

      I normally choose the H.264 - YouTube SD preset. Change to PAL standard (which resets the frame sizes for some reason), crop to 4:3 and change the frame size back to 640 x 480. I just leave all the other settings as default and export.

       

      However with CS5s new preset for Vimeo I noticed that it sets the Aspect Ratio to 1:1 – Square Pixels; while the YouTube preset keeps it at 4:3. I never noticed this before as the exports always looked correct.

       

      Which is right, have I been doing this wrong all this time? What is the ‘best’ procedure to export from PAL video to PC and web video?

       

      Thanks in advance of any replies.

        • 1. Re: Export Settings for Web/PC from PAL
          Jim_Simon Level 8

          You're talking about two different things.  4:3 refers to the display ratio, 1:1 refers to the Pixel Aspect Ratio.

          • 2. Re: Export Settings for Web/PC from PAL
            Castor_uk Level 1

            Hi Jim, thanks for your reply.

             

            I know what you mean, this is what I assumed; but the option in Media Encoder is actually called Pixel Aspect Ratio (PAR).

             

            I thought that as long as the correct aspect ratio was set in the rendered video then the software player should adjust accordingly.

             

            However computer playback should ideally be 1:1 square pixels; and in standard dimensions (320x240, 480x360, 640x360 for wide, etc)

             

            I’m just trying to work out two things.

             

            1. If I follow my usual work process of cropping the source video to 4:3 or 16:9 and then changing the frame width to an appropriate size (e.g. 640x360); does this not already set the PAR to square anyway?
            2. Therefore do I always set the PAR to Square Pixels or to the appropriate setting (4:3, 16:9); or does it not really matter if the above is correct?
            • 3. Re: Export Settings for Web/PC from PAL
              Harm Millaard Level 7

              You are still mixing things up.

               

              Example:

               

              SD PAL material is 720 x 576 pixel resolution. This can be 16:9 with a PAR of 1.4587 or 4:3 with a PAR of 1.0940, but both have the same pixel dimensions with a different PAR.

               

              With PAR 1.00 this could result in 16:9 format in 640 x 360 pixel resolution, in 4:3 format in 640 x 480 (or 480 x 360) pixel resolution. Different pixel dimensions but the same PAR.

               

              Cropping just throws away available information and is generally not the way to go. Start reading on PAR and pixel dimension.

              1 person found this helpful
              • 4. Re: Export Settings for Web/PC from PAL
                Castor_uk Level 1

                Hi Harm, thanks for your reply.

                 

                I thought I understood the difference between Video Aspect Ratio and Pixel Aspect Ratio but maybe not!

                 

                All I’m really after is a reliable way to downsize PAL SD and Wide to PC and Web standards without it becoming squashed or gaining black borders. Most of the online guides I have read say that the final vid should have a PAR of 1:1 (square) and a VAR of either 4:3 or 16:9 – and that the frame size should be 640x480 or equivalent.

                 

                When using the YouTube SD preset in Media Encoder it is set to a PAR of 4:3. Setting the TV standard to PAL I have to set the width back to 640 which in turn sets the height to 512 if the lock is switched on. Manually changing the height to 480 results in huge black bars at the top and bottom but setting the PAR to Square Pixels gets rid of most of them but not all. Cropping the source to 4:3 gets rid of the bars but obviously some of the image as well.

                 

                I also noticed that the other YouTube, Vimeo and iPod presets set the PAR to Square Pixels. Could be that YouTube SD is incorrect?

                 

                 

                I have played around with the new Microsoft Expression Encoder 4. In that I’m able to downsize a PAL video to 640x480 without any blackbars, and that always forces a PAR of 1:1 square.

                • 5. Re: Export Settings for Web/PC from PAL
                  Harm Millaard Level 7
                  All I’m really after is a reliable way to downsize PAL SD and Wide to PC and Web standards without it becoming squashed or gaining black borders.

                   

                  I intentionally left out the rest of your post, because it is not only confusifing to you, but to me too. I can't make heads or tails of the rest of your post, but the quoted statement is very clear.

                   

                  Project is 720 x 576 PAL SD with either 16 x 9 or 4 x3.

                   

                  You want to export with a PAR with PAR = 1.00 with standard sizes for web.

                   

                  Assume 640 x 360 is a convenient size for 16 x 9 material and 640 x 480 for 4 x 3 material. If you need tham smaller, just reduce both dimensions.

                   

                  Export with the codec of your choice, for instance WMV. Set your settings to reflect something like this:

                   

                  31-1-2011 19-06-53.jpg

                  1 person found this helpful
                  • 6. Re: Export Settings for Web/PC from PAL
                    Castor_uk Level 1

                    Hi Harm

                     

                    Thanks again.

                     

                    I think I'm just confusing myself as well as everybody else.

                     

                    Am I right in the assumption that if you resize a 720x576 (D1/DV PAL 1.09) video to a width of 640, the width should be 512?

                     

                    But changing it to Square Pixels should allow a size of 640x480; without any boarders and cropping?

                     

                    If this is right I think I have a problem with something on my system, or the files I’m using. Whenever I have been downsizing to 640x480 (square pixels) I always end up with black borders.

                     

                    If this should not be happening I think a reinstall may be in order.

                    • 7. Re: Export Settings for Web/PC from PAL
                      Harm Millaard Level 7

                      Am I right in the assumption that if you resize a 720x576 (D1/DV PAL 1.09) video to a width of 640, the width should be 512?

                       

                      Correct.

                       

                      But changing it to Square Pixels should allow a size of 640x480; without any boarders and cropping?

                       

                      Correct again.

                       

                      Black borders appear only if you resize 16 x 9 material to 640 x 480 (which is 4 x 3), not if you resize to 640 x 360.

                       

                      To reiterate, export with square pixels like this:

                       

                      16 x 9 -->> 640 x 360

                       

                      4 x 3 -->> 640 x 480

                       

                      Then you will not have black borders. Check it in the Output tab before you queue the file.

                      • 8. Re: Export Settings for Web/PC from PAL
                        Castor_uk Level 1

                        Thanks Harm.

                         

                        I'm not going mad!

                         

                        The videos are definitely 4:3 but I'm still getting the borders.

                         

                        There must be a problem somewhere on the system; I’ll reinstall the software and try again.

                        • 9. Re: Export Settings for Web/PC from PAL
                          Castor_uk Level 1

                          Hi Harm

                           

                          Sorry to open this thread again but I'm still having problems.

                           

                          I reinstalled Premiere Pro/Media Encoder and tried downsizing to computer dimensions (320x240 - square), but I'm still getting borders.

                           

                          I have attached a screen shot showing my settings and the video output, which includes the black borders.

                           

                          Image.jpg

                           

                          The only reliable way of getting rid of the borders is to crop (4:3) on the source tab which obviously loses a small about of pixels from the left and right.

                           

                          Any idea what I'm doing wrong?

                          • 10. Re: Export Settings for Web/PC from PAL
                            Harm Millaard Level 7

                            Castor,

                             

                            If you make it 480 x 352 on export, you lose the black borders. It has something to do with the unsued 'overscan' area in DV material, where the image information is limited to 704 pixels, but the reported format is 720. Obviously when exporting to the web, this 'overscan' information is no longer needed, so instead of using 0.5 x 720 = 360, use 0.5 x 704 = 352. I realize this sounds very confusing and my explanation is very inadequate, but you solve the issue by using 480 x 352.

                            • 11. Re: Export Settings for Web/PC from PAL
                              Castor_uk Level 1

                              Hi Harm

                               

                              Thank's for the information.

                               

                              I had no idea bout the overscan issue. You think that Adobe would have taken that into consideration for PAL when exporting video for web and pc playback.

                               

                              So it looks like you either downsize to non-standard sizes or crop the source, losing some pixels from either side.

                               

                              Downsizing to none-standard dimensions for PC playback is probably not an issue; its web playback where it usually needs to be standard.

                               

                              How does this work with widescreen?