What is the difference between 3d lmks and 2d lmks?

HavenFeng / photometric_optimization

Photometric optimization code for creating the FLAME texture space and other applications

MIT License

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What is the difference between 3d lmks and 2d lmks? #5

Closed SavvaI closed 4 years ago

SavvaI commented 4 years ago

Hi! From the code, it is not clear what is the difference between 3d lmks and 2d lmks? Both have 68 points and both have an effective dimension of 3. As I can judge from the code, 3d lmks are only used for visualization. But what is the actual difference between them, and why 2dlmks have the prefix "2d" even if they are actually 3d? Thanks

HavenFeng commented 4 years ago

Hi, so the 3d lmks are the 68 lmks with fixed jaw contour for visualization while the 2d lmks is the one used for the optimization with dynamic changing jaw contour (it's a function of head rotation angles). The 3 dimensions of 2d lmks are x,y,z in the image plane coordinates, since it's aligned to the input image landmark ground truth, the z value is ignored.