[magick-users] Converting images with padding or cropping based on a max-height

[Anthony Thyssen]

Tuxedo on  wrote...
| I have a simple shell procedure that batch converts original jpeg's in=20
| various sizes into thumbnail copies maximum 75 pixels in height:
| 
| for i in *.jpg
| do convert -quality 70 -geometry x75 $i ../img/`basename $i .jpg`.jpg;
| done
| 
| I'd like it that when a resulting thumb becomes less than 100 pixels=20
| wide to add padding on left and right in some solid color, making the=20
| jpeg including the solid area exactly 100 pixels wide.
| 
| If however a resulting thumb becomes wider than 100 pixels, I would=20
| then then like it cropped on the left and right edges so it becomes=20
| exactly 100 pixels wide.
| 
| This is as if placing the resulting 75 pixes tall image in the center=20
| of a canvas which is exactly 100x75 pixels, and cropping the resulting=20
| thumb only if necessary.
| 
| Exactly how can this be done? Which Image Magick methods and tools are=20
| suitable for this? Any examples would be greatly appreciated.
| 
See IM Examples, Thumbnails, Padding Out Images...
   http://www.imagemagick.org/Usage/thumbnails/#pad

It gives about 4 different techniques in various ways, depending on your
version on IM.


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