7 Replies Latest reply on Apr 30, 2016 3:06 PM by squidkings

    Tracking constant small movement


      Hey everyone,


      So come here as a last resort really.


      I'm in the process of editing a dvd video I'm making for someone to go alongside a book, and basically he just sits on a chair and is talking about and following through with the book.


      The issue I'm having is that because of the studio space we where using and lighting set up, there's a wire going behind his leg and to a light behind him. Looking back I now have learnt to perfect this and make sure there is nothing there in the first place but its too late for that now.


      All I'm trying to do is remove the wire and keep his leg in, so I've created a duplicate layer, and the bottom layer painted the wire out, and the top layer mask just his leg so that it stays in shot and doesn't show the paint going on top of his leg. Now the real issue is that he's constantly moving his leg throughout, even if its small little movement whenever he's talking and sliding etc. but big enough to notice the leg moving away from the mask and either a bit of the wire shows or the paint ontop of his leg shows. I've tried all available tracking methods to track the mask to his leg movement but nothing seems to work, I'm assuming because its just plain black trousers it cant find anything to hook onto, so I've resorted to having to go frame by frame and adjust, but the issue is its an hour and a half long video. I've looked into using mocha ae but still find myself going frame by frame and at this rate will most likely take me weeks to do something that looks so simple.


      Is there anything I'm doing wrong or any other method you can think of that can track this? I've attached photos so you can see the actual clip with the issues.

      Using Macbook Pro 15" Retina with After Effects cc 2015


      Thanks for anyones time on this


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        • 1. Re: Tracking constant small movement
          Szalam Adobe Community Professional & MVP

          This might be an instance where the Roto Brush would actually do a good job. You can't use it intuitively though (it's sneaky that way). Click here to go through some resources first.


          For the record, you say you're using AE CC 2015, but your screenshots are not taken with CC 2015. You're not even using the latest version of CC 2014. The interface went to blue highlights in the CC 2014.1 update (AE version 13.1). but your screenshot shows amber/yellow/orange/whatever highlights. Unless you have some form of visual disability that prevents you from seeing the blue color, I'd suggest at least updating to the latest CC 2014. And, if you do decide to get AE CC 2015, make sure you keep CC 2014 around. AE CC 2015 has some major changes under the hood and some folks have issues with it, so it's a good idea to keep the older version around.

          • 2. Re: Tracking constant small movement
            Rick Gerard Adobe Community Professional & MVP

            If the camera is not moving I would Stabilize Motion using position and rotation. I would pick the entire bottom of the pant leg and maybe the entire knee area. Once the leg is stationary in the frame I'd add a solid, probably red or green on top of the shot and set the blend mode to Multiply so you can see through it and then use a mask to isolate just the part of his leg that is right next to the cord. There is no need to mask anything else. You just start at the first frame and draw your mask, then move forward until the mask needs to be adjusted, make the adjustments and continue. to the end of the shot. You then go back and make any in between adjustments that are necessary.


            When that is done you set the solid as a track matte for the footage. Now you add a null to the scene, reveal position and rotation by pressing p then Shift + r.


            In the Motion Stabilized footage you'll have keyframes for Anchor Point and Rotation. You are going to want to add an expression for Position to the null by alt/option clicking the stopwatch, then drag the pickwhip from the null's position to the anchor point of the footage.


            Now you want to create an expression for rotation by alt/option clicking the rotation property for the null, then type a minus sign ( - ) and then drag the pickwhip to the Motion Stabilized footage Rotation property.


            The last step is to make sure you are at the first frame of the comp and then parent the matte (red solid) and the Motion Stabilized footage to the null. This will put the motion back in his leg and add that motion to the solid matte layer.


            Now find a frame in the timeline where the foot is the farthest to the left and save the frame as a Photoshop File. Next find a frame where the leg is the farthest to the right and save that frame as a Phososhop file. Open both images in Photoshop, place one the left most leg image in the PSD that has the right most leg, split the frame  with a layer mask so you see the most of the wire. Now use the clone or stamp tools to remove the wire and mask most of the shot out so only the repaired area is visible. IOW all you have is the new floor to replace the wire.


            If you really wanted to be fancy you could even clone out the light stand. Now import that fixed image into AE and place it between your matte layer and the footage. Use the matte as an Alpha Inverted matte for the image and you should be done. You can add simple choker to the matte layer to soften and blend the edges.


            If I were at a computer that had AE I could show you a screen shot of the procedure.


            If there is camera movement then there are other problems that you would solve with tracking. You could also use Mocha to generate a matte. Depending on the shot Mocha may be an easier solution.


            I hope this helps.

            • 3. Re: Tracking constant small movement
              squidkings Level 1

              I have to question why the feet are important in a talking head shot? Why not crop to a medium shot?

              • 4. Re: Tracking constant small movement
                pmk96 Level 1

                Hmm my mistake, installed it recently and assumed it was the newest version, will check it out and update, thanks for the advise

                • 5. Re: Tracking constant small movement
                  pmk96 Level 1

                  Thanks so much Rick,


                  This definitely sounds like it will help me, will give it a go tonight and update you

                  • 6. Re: Tracking constant small movement
                    pmk96 Level 1

                    Wish I could, would have made this easier, but the book is on classical guitar techniques and the posture is needed to be demonstrated.


                    I've learnt my lesson now for all future videos and just make sure as little post editing is needed

                    • 7. Re: Tracking constant small movement
                      squidkings Level 1

                      Thats a good lesson. if you put half as much time in preproduction as you've done in post production your projects will be much more watchable.