3 Replies Latest reply on May 27, 2017 8:48 PM by justinm123456

    Drawing Property Boundary in 3d with camera tracking.


      I'm about to give up, buy a Mac, and download FCPX and the drive X plug in.


      I need to create property lines on aerial videos for a client and I can't figure them out. There's an example in the link. I'm assuming it's a shape layer with camera tracking, but I haven't evolved that far in after effects yet. Can anyone help, PLEASE!


      1015 E. Copeland Dr. Video on Vimeo

        • 1. Re: Drawing Property Boundary in 3d with camera tracking.
          Mylenium Most Valuable Participant

          Not sure what you are asking. Nothing special involved. You can find tutorials for 3D tracking like you can find popcorn littered in a cinema - that means masses of them - just like you can find plenty of tutorials on how to use 3D layers. Just connect the dots.



          • 2. Re: Drawing Property Boundary in 3d with camera tracking.
            Rick Gerard Adobe Community Professional & MVP

            The technique depends on the shot. If there is a lot of movement and the shot was made withe a wide angle lens with a lot of distortion you'll need to remove the distortion first. In some cases you may be better off to motion stabilize the shot so the camera motion is eliminated, then use use the pen tool too draw the boundary. If you want to match the perspective you'll need to use a 3D layer.


            Let's say that you have a fairly stable wide shot from about 100 feet in the air and there's not much movement. The property is basically flat but there is a hill on the left. Here are the steps for this hypothetical shot:


            1. Trim the shot and set in and out points so you are not wasting time working on frames that will never be in the final edit.
            2. Change to the Motion Tracking workspace
            3. Select your layer and choose Track Camera
            4. When the tracking is complete scroll through the timeline until you find a shot where most of the property is in the frame
            5. Find at least 3 tracking marks to select at the approximate center of the shot and set an origin and ground plane. The target should look like is is lying precisely on the ground
            6. Now hold down the Alt/option key and adjust the size of the target by clicking and dragging until it pretty much fills most of the property (might be the Ctrl/cmnd key)
            7. Hold down the Ctrl/Cmnd key (might be the Alt/Option key) and click and drag to center up the target on the property so that it looks like it is laying on the ground
            8. When the target is in the right place right click and add a camera and a solid as a place holder
            9. Rotate the solid carefully using the Transform>rotation properties to square it up with the geography
            10. Now apply the Grid effect to the solid and preview the shot to make sure that the perspective matches. If your target was good the perspective should match up just fine, if everything is off delete the camera and solid and start at step 4 again. If the grid looks good move on
            11. Create a new shape layer using the pen tool and start drawing a path with a fairly large stroke and no fill that extends almost completely across the screen
            12. Change the shape layer to 3D (it may disappear or be in an odd position but we'll fix that in the next sRep)
            13. Maker sure the Parent column is visible in the timeline (check the help files if you do not know how to work with columns in the timeline by using the search help field at the top right corner of AE)
            14. Hold down the shift key and parent the shape layer to the solid to snap the shape layer to the same position rotation and scale of the solid layer you added in step 8
            15. Turn off the solid layer and select the pen tool (g) and edit the path and continue drawing it so that the property lines line up.
            16. Check your work by scrolling through the timeline
            17. If all is well then move to a point in the timeline where the hill on the right side of the screen is approximately centered in the screen
            18. Select the Camera Tracking effect in the Effects Control Panel to make the tracking marks visible and select at least 3 tracking marks on the hill that line up the geography
            19. Follow steps 6 and 7 again to position and size the target to get it to line up with the hill
            20. Right click and add a second placeholder solid to the shot
            21. Check the shot again by using the grid effect to make sure that the solid is lined up and properly positioned on the hill using step 9 and 10
            22. Create a second shape layer as you did in step 11 and continue through step 16.
            23. Repeat for as many different planes you have on the property
            24. Once the shape layers are all completed and the property lines line up perfectly you are ready for the final polish to your shot
            25. If there are buildings or other objects that you wan to have pass in front of the lines you'll have to add some more solids that match their geometry and then use those solids and mask tools to do some rotoscoping and then use the roto as track mattes for the shape layer property lines.

            There you go. That's how to do it For the hypothetical shot I described.


            If the shot is different you may be able to do it with a lot less work by simply motion stabilizing the shot and then drawing a shape layer, then re-introducing the motion with a simple expression and a null and parenting. This second hypothetical shot would take about 10 minutes to do, the Camera Trackikng example could easily take a couple of hours.


            If this does not get you close to a solution then you will need to spend some time studying and practicing some basic AE tracking skills and learning how to work in AE's 3D space. If this project was for a class I might teach in AE to a beginner I'd probably spend at least a couple of hours introducing the tools and the workflow and give the students a couple of hours to do the shot.


            If you still can't get a handle on the workflow please post the shot your are working on to so we can give you some better directions.

            • 3. Re: Drawing Property Boundary in 3d with camera tracking.
              justinm123456 Level 1

              Thank you. I'll give that a try