The walls of the well are located at x=0.25 and x=0.75. Each frame gives the solution to the TISE begining with an exponetially decaying solution as on the left. Successive frames show the solutions for increasing values of the energy E. Note the increase in curvature in the oscillating (classically allowed) regions as the energy increases.
The eigenenergies (allowed pure energy states) occur at the sensitive points where the solution is also exponentially decaying on the right hand side of the well, near frames "out0036" and "out0072" and "out0104".