2D Bilinear Interpolation

[bagarman]

Good day
I need your help again and that I wanted to know how to make a matriz (2D Arra) bilinear interpolation can, I have found a program but I do not know how to operate the Program.
I wanted to know is why there are the rows and columns index.
So how do the interpolation matrix for example 128 * 128 matrix.
Thank you very much

[altenbach]

Hey, thats my VI. 😄

Anyway, it is basically a 2D version of "interpolate 1D array".

This means you can index into a 2D array with noninteger indices and it will return a bilinearly interpolated value corresponding to the fractional index.

Have a look at this picture (from here😞

Message Edited by altenbach on 04-05-2010 12:15 AM

[bagarman]

Good day Altenbach thank you for your answer, but I have a question. I tried using your program a 64 * 64 matrix interpolated but failed. can you tell me how it works with rows and columns works. Thank you very much

[altenbach]

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bagarman wrote:
I tried using your program a 64 * 64 matrix interpolated but failed.

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Failed in what way? (incorrect result? broken wire? computer bursts into flames?)

Do you want to simply get a value for a fractional position or do you want to create a new, larger array that has more "pixels" (such as my image above)?

Say you have your 64x64 array. Using the plain "index array" you can get any element, given its integer index (e.g. [0;0], [45;30], [12;55], etc.) . The index is limited to integers.

Using my bilinear interpolation tool, you can get a value for a fractional index (e.g. [0.6;0.7], [45.1;30.7], [12.9;55.2], etc.) and you get the bilinearly interpolated value.

Maybe if you could attach your code attempt to make it more clear what you actually want to do. Thanks! 

[bagarman]

Hi Altenbach,
Thanks for your answer.
So to my problem, I sound for an object using ultrasonic sensor, the sensor is rotated by means of rotating motor, and I'll take the measurements, these measurements should represent a B-mode ultrasound.
and the measurements of polar coordinates transform in cartesian, and the coordinate transformation holes created in the image, these holes are to be suppressed, and the fractional index, I post out my end matrix.
Thank you Altenbach