4 Replies Latest reply on Oct 6, 2015 11:28 PM by Rick Gerard

    Motion tracking obscured shot

    Satori70

      I'm trying to motion track a shopping bag with perspective corner pin to replace the arabic logo but half the bag disappears behind the other bag and I can't get a full track. Does anyone know how I can solve this. Thanks.

      Screen Shot 2015-09-27 at 16.51.36.png

        • 1. Re: Motion tracking obscured shot
          Rick Gerard Adobe Community Professional & MVP

          I would do the track in Mocha so you can ignore the bag in front. You can also do the roto in Mocha.

           

          Another option would be to stabilize the shot for position rotation and scale then roto the bag in front to separate the shot into layers, then replace the logo and animate as well as you can to match, then remove the stabilization and add the motion to the logo replacement. The easiest technique depends on what is happening in the shot. Just a simple corner pin track isn't going to work very well because there is very little texture on the bag.

           

          There are lots of tracking tutorials on the Imagineer site. I'm working on a tutorial for stabilizing, roto, then put the motion back tutorial that would cover the entire procedure. It should be ready soon. I'll put it up when it's ready. It involves stabilizing the shot so the object of interest does not move in the frame. Renaming the stabilized footage stabilized, doing any roto needed, adding in the new elements and adjusting them as needed, then adding a null and applying this animation preset to the null, then parenting all of the layers to the null to remove the stabilization and add the motion to the added elements.

          • 2. Re: Motion tracking obscured shot
            Satori70 Level 1

            Thanks Rick. I took your second option of stabilizing the shot for position rotation and scale and then masked the bag on top. Worked just fine.

            • 3. Re: Motion tracking obscured shot
              Mathias Moehl Adobe Community Professional

              I think Rick's first suggestion (doing it in mocha) is usually the best and most accurate way to do it.

               

              In this live webinar recording  I show how to do this in mocha (the relevant part starts at about 18:40).

              mocha_webiniar.jpg?itok=zDq1axKi

              Learn mocha AE - Online Training Webinar | mamoworld

              • 4. Re: Motion tracking obscured shot
                Rick Gerard Adobe Community Professional & MVP

                The best method depends on the shot. I do about 80% of my shots like the one you described by stabilizing in AE and then doing a hand roto. It's very quick and easy to do on many shots and takes me much less time than doing the same shot in Mocha. On other shots Mocha is the best tool. The point of the whole discussion is that there are many ways to do the same task when you are compositing. The best tool and the best workflow depends entirely on the shot. No one solution is best all of the time.