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From: Cecil Westerhof <Cecil@decebal.nl>
Newsgroups: comp.lang.java.programmer
Subject: Re: Can you resize with BufferedImage
Date: Wed, 12 Apr 2017 14:08:29 +0200
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On Wednesday 12 Apr 2017 12:18 CEST, Martin Gregorie wrote:

> On Wed, 12 Apr 2017 10:34:04 +0200, Cecil Westerhof wrote:
>
>> In my code I have the following code:
>> dest = image.getSubimage(x, y, dispWidth, dispHeight);
>>
>> This is the part that I want to select, but I want to resize it at
>> the same time. In this case I would like to scale to 50%. How
>> should I do that?
>
> Use an AffineTransform. 
>
> The image resizing code should look something like this fragment:
>
> AffineTransform at = new AffineTransform();
> at.scale(scale, scale);
> AffineTransformOp op = new AffineTransformOp(at,
> AffineTransformOp.TYPE_BICUBIC);
> Double nw = new Double(w * scale);
> Double nh = new Double(h * scale);
> om = new BufferedImage(nw.intValue(),
> nh.intValue(),
> BufferedImage.TYPE_3BYTE_BGR);
> op.filter(im, om);
>
> where:
> im    is a BufferedImage containing the old image
> om    is a BufferedImage to hold the modified image
> scale is a double containing the required scaling factor
>
> I'm scaling images to a width of 400 pixels, so I calculate scale as
> 400.0 / image_width. You would just set scale to 0.5. I want to keep
> the image proportion, so I use the same scale value for both width
> and height.

Does not look to difficult. Just to be sure I understand it correctly.
I first cut the part I want and then I do the scale. So my dest
becomes im. And then I use your code.

-- 
Cecil Westerhof
Senior Software Engineer
LinkedIn: http://www.linkedin.com/in/cecilwesterhof