How to animate measurements and text on a plot of land in After Effects (with Mocha and 3D camera tracking)

1. Duplicate the footage and open Mocha

Import the shot into a composition and duplicate it with Ctrl + D (or Edit > Duplicate).

Select the copy and go to Animation > Track in Boris FX Mocha. The Mocha icon appears in Effect Controls: click it to open the Mocha window.

2. Draw the corners of the plot

Inside Mocha use the zoom tool (drag up to zoom in) and the hand tool to frame the image.

With the pen, place a point on each corner of the plot. A four-sided plot needs four points; if it has three sides or isn't rectangular, add as many as it needs. Right-click to close the shape.

To fine-tune the corners, click the small blue square on each vertex and drag it outward.

3. Track and correct

Click the track forward button (on the right side of the panel). Mocha follows the camera movement using the shape you drew.

Scrub through the timeline. If at some point the shape slides off the plot, use the tool next to the hand to move the points back into place. Repeat until the end of the shot.

Save and close Mocha.

Tip: Don't worry if the shape slides while tracking: you fix it by hand on the frames where it fails.

4. Create the mask in After Effects

Back in After Effects, in the Mocha effect options find Matte > Tracking Data and click Create AE Mask. This creates a mask that follows the same camera movement.

Hide the layer below (the original footage) to check that the cutout looks right.

5. Draw the animated border

Apply Effect > Generate > Stroke to the layer with the mask. Adjust the brush size and color (the video uses a size of 3).

To make the border draw itself, set End to 0%, add a keyframe, move forward one second and raise it to 100%.

Move those keyframes one second later so the drone flies for a moment before the border starts drawing.

Select the keyframes and apply Keyframe Assistant > Easy Ease (F9) so the movement is smooth.

6. Fill the plot with color

Apply a fill (Effect > Generate > Fill) to the footage and choose the plot's mask so the color stays inside the border.

Set Opacity to 0% where the stroke starts drawing and raise it (to 20% in the video) when the stroke finishes. A few seconds later bring it back to 0%: the color fades in and out.

You can copy and paste those opacity keyframes so the color shows up again later in the shot.

7. Add the area with the 3D Camera Tracker

Select the footage and apply Track Camera. When it finishes you'll see track points all over the image.

Pick 3 to 5 points on the plot, right-click > Create Text and Camera.

Adjust the size and position of the text and type the plot's area. The text stays anchored and moves exactly like the drone shot.

Tip: Move the text with the gizmo arrows, don't drag it freely: if you drag it, it stops being anchored properly.

8. Export

Save with Ctrl + S. With the timeline selected press Ctrl + M (Composition > Add to Render Queue), then choose a folder and a file name.

Exporting from Adobe Media Encoder is recommended: in the video's example the final file is about 16 MB.