4 Replies Latest reply on Nov 15, 2012 7:10 AM by Mylenium

    After effects CS6 , 3D Camera tracker problem


      In first row i want to provide you my pc specs:

      AMD FX 4100 Quad core @ 3,6-3,8 GhZ

      8 GB of RAM

      Windows 7 Ultimate 64 bits

      300+ Free HDD space

      gpu: nVidia 9500 GT @ 1GB DDR3

      AAE CS6


      In 2nd row the footage is recorded in Gta San Andreas  its a 1280/720  , 29.97 frames per sec , size 11.1 mb , windows media video

      link for footage : http://www.youtube.com/watch?v=LeuKJWSL97g&feature=youtu.be

      link for screen with error : http://i48.tinypic.com/xcvwg3.png


      Have to mention that the original fps of the file was 23

      I made it work on ther same footage but the error didnt appear on when the camera was moving straight( my deduction )









        • 1. Re: After effects CS6 , 3D Camera tracker problem
          Mylenium Most Valuable Participant

          Nah, sorry, this shot cannot be solved by any 3D tracker on this planet. The view changes too much from frame to frame and given the first person perspective, none of the reference objects will be visible for more than a few frames. This simply cannot work for mathematical and technical reasons.



          • 2. Re: After effects CS6 , 3D Camera tracker problem
            elegz Level 1

            Thanks for you help ''The view changes too much from frame to frame'' thats all i wanted to know , i will try to record it at a slower speed and in only one dirrection  and my deduction was right it worked only when the camera was moving forward.






            • 3. Re: After effects CS6 , 3D Camera tracker problem
              Rick Gerard Adobe Community Professional & MVP

              You're not going to get better results by recording it slower. You are not understanding the purpose 3D tracking. 3D tracking is used to put a CGI object in a scene  so that the CGI object sticks to the ground. I'm imagining that you want to put something like a character in this scene. If you want to have the character move through the entire scene then 3D tracking won't keep up in a single track. You may, however, be able to track the scene for one or two seconds. Let's say you have a shot that is moving down a street and around a corner. There is a tree on the right side of street. You can usually track successfully from where the tree enters the scene to where the tree leaves the scene. That's about it. Then you have to cut the shot and start again.


              You also need detail for tracking to work. Game backgrounds have tied textures and repeating lines. These confuse the heck out of tracking software. What do you see in this frame from your movie that has enough detail to track? There' not much that can be used for 3D info.



              Your only chance is to cut the shot up into short sections, track those, then put the scene back together later. It's not going to be a one click solution.

              • 4. Re: After effects CS6 , 3D Camera tracker problem
                Mylenium Most Valuable Participant

                As Rick said, you're misunderstanding. Recording at different speeds will do nothing. For a proper 3D solve, a minimum number of reference points will have to be visible all the time. You cannot achieve that by zapping through the scenery. If at all, you'd have to have either a camera that moves reasonably only within a room/ yard or a full view of the 3D scenery to reconstruct the scene - anything that allows the tracker to detect the same edges/ points in every frame e.g. of a camera move. And yes, Rick has a point about the absence of small details, too. It's simply nothing that will work particularly well for a 3D track, even if you split it up into multiple segments or match multiple angles from the same scene. In the end, it might in fact be much easier to export such stuff from the game's level editor, if such a thing exists...