Now that you understand what pose estimation is, let's see how you can use it to track planar objects. Let's consider the following planar object:
Now if we extract feature points from this image, we will see something like this:
Let's tilt the cardboard:
As we can see, the cardboard is tilted in this image. Now if we want to make sure our virtual object is overlaid on top of this surface, we need to gather this planar tilt ...