[magick-users] Resizing to minimum res and filter question

[Anthony Thyssen]

On Sun, 29 Mar 2009 14:48:53 -0700
Fred Weinhaus <fmw at alink.net> wrote:

| 
| I believe the documentation is in error!  The ''<", is supposed to 
| work if you want to expand an image, not reduce it, to my knowledge.
| 
| 
| 
| The docs says:
| 
| widthxheight<
| Change dimensions only if both specified dimensions exceed image dimensions.
| 
| but should say
| widthxheight<
| Change dimensions only if both specified dimensions DO NOT exceed 
| image dimensions.
| 
>From IM examples,  Resize and Scaling
http://www.imagemagick.org/Usage/resize/
  Only Shrink Larger ('>')
  Only Enlarge Smaller ('<')

You want '>' not '<'

| Lanczos is probably best for minimizing. Anthony believes Mitchell is 
| better for maximizing.
| 
These are also the defaults. unless the image contains transparency where
Lanczos then falls back to Mitchell again to avoid VERY BAD ringing effects
for the alpha channel with undefined colors.

I would also say, and I repeated myself many times in the above document.
Go with the defaults, unless you understand what you are doing,
OR trying to achieve weird effects (such as heavy blurring while enlarging
small colored gradient generating images)

  Anthony Thyssen ( System Programmer )    <A.Thyssen at griffith.edu.au>
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