When using cell phone camera to take group portraits, the people on the extreme left and extreme right are stretched in the (predominantly) horizontal direction as a natural result of optical projection. This makes these people appear unnaturally fat. The same effect also appears with a SLR camera with short or wide angle lenses (f<35mm). PigByeBye remaps the optical projection, effectively squeezing out this stretch. PigByeBye makes a wide-angle group portrait match better to how a human with naked eyes would see in the scene.