Re: Image Rotating, zoom and interpolation algorithm???

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Yang Ming-liang wrote:
Hello, Everyone!
I am working on a scanner application development. The software needs
some basic functions like rotating, zoom, and so on.
Our scanner has very large size about 60 * 91(A1 breadth), so the image
is very large too. It must use interpolation algorithm, or the image`s
quality is too poor.
The key problem is the large image-rotating(zoom) always take too many
times!
I have read some papers about the interpolation, but I cannot sure which
should be chose.
Is anyone could give me some advices about this???
Thanks!

A1 format is 594×841 milimeters which say in 320dpi (low) will create images of resolution like 7454x10553 pixels. 32bpp image of this size will require approximately 300mb
In 1200 dpi image would require almost 5gigabytes.
So: 1. make sure you have enough memory if not any operation will be slow.
2. use simple intearpolation algorithm (linear) - this will still take few seconds for image of that size.

Where exactly you need to use interpolation? You want to decrease resolution of hi-res image and keep high quality?

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