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strching the image
Write a function that takes a picture and two integer values and stretching the image by dimensions
New/
somebody can help me with this i dont know how to start
New/
somebody can help me with this i dont know how to start
Well, it's kinda hard to help given that we don't know how the picture is stored, or what libraries you're using (or are these console "pictures"?) or what algorithm you're supposed to use for scaling the image.
Could you provide those details? Thanks.
-Albatross
Could you provide those details? Thanks.
-Albatross
t3_0.PGM t3_3.PGM rescale 330 580
ImageViewer2 console pictures
Two-dimensional matrix as an array of values, where each value represents a degree -
Particular pixel gray field of [0,255] when it's 0 white and 255 black : image we will be working on it.
shown below and the initial large is 800 * 600 pixels.
To view photos we have provided you with a view tool called ImageViewer2 sure to use it and not others
ImageViewer2 console pictures
Two-dimensional matrix as an array of values, where each value represents a degree -
Particular pixel gray field of [0,255] when it's 0 white and 255 black : image we will be working on it.
shown below and the initial large is 800 * 600 pixels.
To view photos we have provided you with a view tool called ImageViewer2 sure to use it and not others
It is a homework assignment.
(Not a very nice one, for the grade level.)
The idea is one of sampling. Given an index x into the range [x0, xN-1]:
how do you convert that x to a y in the range [y0, yM-1]?
Answer: if the index is some percentage of the way across the xs, it should be the same percentage across the ys. A little math and you can convert the index from one range to an index into the other range. (Remember that a percentage value must be floating point, while indices are integers.)
You will need to work backwards. Your xs are the target image (the one you want to create), and the ys are the source image (the one you want to scale).
The tricky part is deciding how to get colors out of the source, since the percentage across will rarely be exactly on a source pixel. You have three basic options:
(simplest) truncate the percentage to an integer index and use that pixel value
(simple) choose the source pixel closest to the percentage
(not simple) do the same percentage thing to the pixels on either side of the percentage point to
get the proper grayscale value.
I recommend, actually, that you do the (simplest) first, so that you can see some working results, then add the (simple) or (not simple) approach.
If this is still confusing to you, post back.
(Not a very nice one, for the grade level.)
The idea is one of sampling. Given an index x into the range [x0, xN-1]:
how do you convert that x to a y in the range [y0, yM-1]?
Answer: if the index is some percentage of the way across the xs, it should be the same percentage across the ys. A little math and you can convert the index from one range to an index into the other range. (Remember that a percentage value must be floating point, while indices are integers.)
You will need to work backwards. Your xs are the target image (the one you want to create), and the ys are the source image (the one you want to scale).
The tricky part is deciding how to get colors out of the source, since the percentage across will rarely be exactly on a source pixel. You have three basic options:
(simplest) truncate the percentage to an integer index and use that pixel value
(simple) choose the source pixel closest to the percentage
(not simple) do the same percentage thing to the pixels on either side of the percentage point to
get the proper grayscale value.
I recommend, actually, that you do the (simplest) first, so that you can see some working results, then add the (simple) or (not simple) approach.
If this is still confusing to you, post back.
Can we just use the image sizing function to strech image by changing image width and heigth and adjusting image resolution, which comes from an image processing library?
http://www.rasteredge.com/how-to/vb-net-imaging/resize-image/
http://www.rasteredge.com/how-to/vb-net-imaging/imaging-processing/
http://www.rasteredge.com/how-to/vb-net-imaging/resize-image/
http://www.rasteredge.com/how-to/vb-net-imaging/imaging-processing/
> Not a very nice one, for the grade level.
¿and which grade is it?
It looks appropriate for a class in image processing, by instance.
¿and which grade is it?
It looks appropriate for a class in image processing, by instance.
It's a common CS-200-type homework.
If OP had a class in image processing, the word resampling would have appeared in there somewhere, along with any number of filter algorithms.
If OP had a class in image processing, the word resampling would have appeared in there somewhere, along with any number of filter algorithms.
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