stereo decoding

We have

1. Fitted data
2. Differentiation data

Theory

1. The displacement of the side wall in the norm direction, i.e., 45 degree to horizontal or vertical.
2. Left: inner edge, bottom
   
1. Horizontal: Positive direction: center -> brim
   
2. Vertical: Positive direction: upwards
3. Right: outer edge, bottom
1. Horizontal: center -> brim
   
2. Vertical: downwards
4. Wall movement is the vector sum of hori and vert: dH^2 + dV^2 = dW,
   
5. Sign of wall movement...
   

Reanalysis

1. Sidewall 45-degree system,
   
2. e.g. left = in norm direction, sidewall displacement
3. displacement = dist_point_to_line( bottom(t1), sidewall(t2)) * higher_than(z_bottom_projection, z_bottom)

Pitfalls

1. sidewall(t1) may not parallel sidewall(t2)
   
2. system error proportional to the position of the point representing the wall, when calc dist_point_to_line()