7 Replies Latest reply on Feb 2, 2011 2:39 AM by ljeco

    Aspect Ratio

    ljeco

      I'll eventually be exporting my current project to display on a 42 inch (16:9) flatscreen TV. Current project files (AVI DV2)  is in 4:3. I know you can convert to 16:9 using programs like gspot. But i presume that involces cropping (based on a play around in Gspot).

       

      If this is true.. how much impact does cropping have (how much of your image do you lose and what is the impact on quality/resolution converting from SD to HD?).

       

      Also, really just for my own interest.. does the aspect ratio actually change the dimensions of the pixels, or jsut the number of pixels in each direction?

       

      Also for interest sake while i'm at it.. is it at all possible to convert videographic formats (4:3) to beyond 16:9 (say, cinematic 1.85:1 or 2.39:1). If not how would you best go about showing a 4:3 film in a theatre?

        • 1. Re: Aspect Ratio
          ljeco Level 1

          Actually after just viewing a project i created in 4:3 on my 16:9 TV i was curious as to how it still displayed quite well across the whole 42 inches.

           

          This did a bit to explain the fundamentals..  http://www.michaeldvd.com.au/articles/16x9Enhancement/16x9Enhancement.asp.

           

          I presume then that my DVD player is somehow converting the 4:3 to fit 16:9 (which i would imagine should look stretched, but it 'appears' fine)?

          • 2. Re: Aspect Ratio
            Steve Grisetti Adobe Community Professional

            It sounds like your DVD player is doing a great job of upconverting!

             

            I wouldn't recommend trying to "fix" something that's not broken.

            • 3. Re: Aspect Ratio
              the_wine_snob Level 9

              First, G-Spot is an AV file information utility, and only tells you what is enclosed in the AV files' format "wrapper." It will also tell you which CODEC's you have installed on your system, and if you have the ones necessary to play the particular AV file.

               

              When going from 4:3 to 16:9, there are some possible solutions. Sounds like one, letting the player and/or TV handle it, is working for you. As this method is hardware, and setting dependent, it might not work so well, for others. Things will depend greatly on what equipment they have, and how it is setup.

               

              Two other ways to handle this Aspect Ratio change is to alter the Video. First, with SD video, the pixel x pixel Aspect Ratio is the same, but the PAR (Pixel Aspect Ratio) differs. For NTSC, Standard 4:3 has rectangular pixels, that are taller than they are wide (0.91:1), while Widescreen 16:9 has rectangular pixels, that wider, than they are tall (1.21:1). One could just change the PAR form 0.91 to 1.21, BUT subjects will then "stretch" out, and Aunt Marge might not like gaining 15 pounds!

               

              Another is to bring in the 4:3 footage into a 16:9 Project, and then apply the fixed Effect>Motion>Scale to expand the width to match the 16:9, effectively cropping off top, bottom, or both. One could then use Motion>Position, to determine what part(s) of the vertical image is effectively cropped. This has two disadvantages: the Scale will slightly degrade the image, as the program has to build pixels, where they did not exist, and that some of the vertical image will be lost.

               

              Compromises - compromises. If your hardware is doing a good job, that is "as good as it gets," but you might need to instruct others how to set their hardware up.

               

              Good luck,

               

              Hunt

              1 person found this helpful
              • 4. Re: Aspect Ratio
                ljeco Level 1

                Thanks Bill,

                 

                yeah i'll just shoot in 16:9 next time, seems easier to go backwards from it than the other way around?

                 

                Sounds like there are some options down the track, none ideal, but when the time comes will certainly have a play around! Filing response under folder 'to do near end of production'. As always, advice most appreciated

                • 5. Re: Aspect Ratio
                  the_wine_snob Level 9

                  Yes, if you shoot in 16:9, the solution is to just effectively crop off one, or both sides, and one can use the fixed Effect>Motion>Position to locate the wider Clip in the narrower 4:3 aperture. There is no scaling needed.

                   

                  When going from 4:3 footage to a 16:9 Project, the ultimate method is to leave the pillar box black bars, and the Motion>Scale is less desirable, as you will degrade the image slightly, and then have to effective crop off the top, and/or bottom. Some do not like the pillar box look, so the Scale is their only option.

                   

                  Good luck,

                   

                  Hunt

                  1 person found this helpful
                  • 6. Re: Aspect Ratio
                    the_wine_snob Level 9

                    Another treatment, but this would depend on the aesthetic feelings of the editor, and the subject matter.

                     

                    If you watch FoxNews, and some other news outlets, they have monitors on set, that are 16:9. When they have footage shot in 4:3, they get rid of the pillar boxes, by having an abstract 16:9 background video, that is heavily Blurred, and is also "ghosted" back in both Brightness & Contrast. This runs behind the 4:3 footage. Some news outlets will even run their station's/channel's/network's name in the pillar boxes, to make them look like graphics elements, and distract the viewer from empty black bars on both sides. Again, this can be effective, or horribly distracting. However, keep that in the back of your mind.

                     

                    Good luck,

                     

                    Hunt

                     

                    PS - This ARTICLE will give you some tips, primarily for solving the issue of vertical slides in a SlideShow, but it applies to 4:3 in 16:9 Projects, as well.

                    • 7. Re: Aspect Ratio
                      ljeco Level 1

                      Yep i know exactly the sort of thing, but guess had never thought about it til you mentioned it (in which case i assume they were using the 'effective' version rather than the horrible!).

                       

                      Looking at your muvipix article makes me want to go right out and make a nice slide show now! Very effective, and some nice shots too, looks like you manage to enjoy yourself very well!

                       

                      Thanks again for the advice, always a great learning experience around these traps! Cheers, LJ