In: Computer Science
Explian interpolation: bilinear interpolation, subject is digital image processing.
Interpolation is the process of estimating the unknown values between two known values.For example suppose a line which passes through two points.We can estimate the points in between those points by using the method of interpolation.
In bilinear interpolation we are finding the missing pixel in such a way that by taking the weighted average of nearest pixels.Suppose that M is the missing pixel.Pl,Pr,Pb and Pt are the points on left,right,bottom and top pixels and Dl,Dr,Db and Dt are the distance of left,right,bottom and top pixels from the missing pixel.Then the following formula can be used for finding the missing pixel in bilinear interpolation.
M=(Pl*Dr+Pr*Dl+Pb*Dt+Pt*Db)/Dr+Dl+Db+Dt
Note that weight of the pixel is inversly propotional to the distance of source and desination pixels.
It is actually an extension of linear interpolation fo interpolating functions of two variables on a regular grid. Linear interpolation is performed first in one direction and then in the other direction.