bilinear or licubic

[cmk128]

Hi All
I want to enlarge my bitmap, i have read many articles in Google
but still have concept problem about bilinear/bicubic. I am confusing
about the "fill in sequence of the new pixel"

For example, if i have a 2x2 pixel bitmap, i represent it as:

xx
xx

And i enlarge it to 8x8, so i have this now

x???x???
????????
????????
????????
x???x???
????????
????????
????????

The ? is the unknown pixel, which is the new pixel, i need to use
bicubic to calculate its RGB value.

My *major* problem is, which ? pixel i should fill in first. If you
tell me i should fill in the left-most one in the topest row. Then i
come with another problem: I don't have enough known pixel to calcuate
its value.

PLEASE GIVE ME A HELP

thanks
from Peter ([email protected])

 

[Oliver Wong]

I want to enlarge my bitmap, i have read many articles in Google
but still have concept problem about bilinear/bicubic. I am confusing
about the "fill in sequence of the new pixel" [...]

My *major* problem is, which ? pixel i should fill in first. If you
tell me i should fill in the left-most one in the topest row. Then i
come with another problem: I don't have enough known pixel to calcuate
its value.

If your question is about how to do this in Java:

http://www.java-tips.org/java-se-tips/javax.imageio/java-2d-api-enhancements-in-j2se-5.0.html

If you need to implement this yourself (e.g. because it's homework or
something), then this doesn't really have anything to do with Java. Try
http://members.bellatlantic.net/~vze2vrva/design.html and seek a math or
programming group if you're unable to follow the explanations there.

Note that if you think one of the steps is to exactly copy over a pixel
value from the original image, you've already misunderstood how bicubic
works.

- Oliver