how to resize an image mantaining aspect ratio.
lazarus / 39-Graphics

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dcelso · 2013-01-27 11:50

hello to all. I have program to load a image on a timage. The image
can be any known format of timage can load.

I need put a preview of the image in a 50x50 container so i want
resize it maintaining aspect ratio. The result will be a 50x? Image or
?x50 image.
 what is the better method to do it.?

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User137 · 2013-01-27 12:50

Use math and logics. You get the relative size by Width/Height. For
example 400x200 would give you 2, also that 200x200 image would result
1. So if x>1, then image is horizontally bigger. Same relation number
can be used as a multiplier.
For example if you draw image horizontally, you can
image.width := 50;
image.height := 50 / x;

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dcelso · 2013-01-27 13:16

Yes. I know it. But what function and image container can i use in
Lazarus? For example Tlazimginterfaz has methods to do it?

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User137 · 2013-01-27 14:30

TPanel and TImage in it for example. TImage has Stretch property which
you could use in this case.

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dcelso · 2013-01-27 15:04

, thanx i will try it