2 Replies Latest reply on Dec 17, 2012 10:52 AM by John Ratard

    Copy roto selection to same position in all frames

    John Ratard Level 1

      I am using AE CS5 in Production Premium. I also have moca AE 3.1 that may be a better way of trying to isolate an object using planar tracking.  I need to replace an item that appears in the same position on all frames of a clip.  This is a previous problem I covered some time ago involving a spiders web that was fixed on an 8mm film gate.  As a result, the web appears on the top left hand corner of every frame in the clip.  Perhaps a different approach will work.  This is complicated because the background behind the item changes such that the boundaries of the selected item become blurred.  I will need to further isolate sections of the clip where there is similar background interference, e.g. a background of mostly dark trees in the top left may to be passable.  There may be a way I can gradually replace the web with background that appears in following frames as the background moves by using duplicate layers.

       

      How can I roto select the item in the first frame and copy the boundaries of the selection to all frames or is there a better way of doing this?

        • 1. Re: Copy roto selection to same position in all frames
          Mylenium Most Valuable Participant

          How can I roto select the item in the first frame and copy the boundaries of the selection to all frames or is there a better way of doing this?

           

          You don't. You're thinking in wrong terms here and will work yourself to death if you follow that approach. Instead export a frame, isolate the pattern as a clean greyscale image in Photoshop. Then you can either use it as a matte to punch out the disturbances directly or by creating proper transparency, possibly in a pre-composition by using it as a luma matte on a white solid, as an input for an adjustment layer. Then you can eitehr just fill in the blanks with a copy of your footage that you have slightly shifted in position or in the second case apply effects liek Minimax, Matte Choker and varius blurs to fill the gaps. CC VEctor Blur with the transparency channel as the input will do miracles to "sew" such stuff together. Of course you might also consider RevisionFX' RE:Fill as sort of a canned and pimped plug-in tool set for these kinds of things...

           

          Mylenium

          • 2. Re: Copy roto selection to same position in all frames
            John Ratard Level 1

            Thank you so much for your suggestions.  I do not have much experience with mattes so this will be good experience for me.  I will see how this can hopefully be applied automatically to all frames using a shift to a masked duplicate layer.  The unmasked area of the duplicate will include the top corner spiders web.  Since the top of some frames includes sky and a line of dark tree while others show the sides of an aircraft with little detail, the end result should be what I am looking for.  Fortunately, there are no people or major detail in the top of any frames.

             

            John