Face alignment megaface

Question

i was looking into face recognition and i came across this method to face transform using similarity transform to align faces detected by mtcnn for the megaface dataset, in that the source matrix being used was

src = np.array([                                                                                                                                                                     
 [30.2946, 51.6963],                                                                                                                                                                
 [65.5318, 51.5014],                                                                                                                                                                
 [48.0252, 71.7366],                                                                                                                                                                
 [33.5493, 92.3655],                                                                                                                                                                
 [62.7299, 92.2041] ], dtype=np.float32 )

can anyone tell me from where do we derive this matrix? and/or why this is used?

reference: https://zhuanlan.zhihu.com/p/29515986

Answer 1

I figured it out, basically, the points are the landmark points of a face that resides in a 112,96 image, the nose is centered in the image and thus transforming landmark points of another face onto these points will center align a face just like these template landmark points