[Work Log]
June 26, 2013
Tasks
- Likelihood construction,
clean_correspondence3.m - new tracking GP model
Likelihood construction
Started and finished implementation today. Need to design a test and then debug.
~ 250 lines of Matlab code. Logic overview:
- smooth triangulated points
- resample smoothed 3D curve uniformly
- handle tails (see below)
- project curve into each view and resample uniformly
- DTW to correspond 2d data curve to projected smooth curve (see below)
- map corresponding projected curve points back to 3D points and indices
- triangulate 2d data points against corresponding 3d point
- compute likelihood hessian around that point
New DTW
Re-implemented a specialized version of DTW with following changes:
- only horizontal steps accrue cost
- Hard-constraint on the number of vertical steps per horizontal step.
- keeps track of "best" match along vertical runs. no need for second pass
- I think this is only possible because only horizontal steps accrue cost.
Tail points
Still iffy on the "tail points" case. Implemented late at night and likely needs review in the morning. Still need to handle negative index values.
Alternative implementation: only inspect the tails to determine the length of the 3D curve. Then proceeed as usual. no special cases
TODO
- review tail points code
- consider alternative implementation (see above)
- handle negative index values
- think about hessian and transformation Jacobian
- testing, debugging, profiling