Thread: thumbnail sizes
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Old January 12th 18, 07:05 PM posted to rec.photo.digital
Phillip Helbig[_2_]
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Posts: 25
Default thumbnail sizes

In article , "Carlos E.R."
writes:

On 2018-01-07 23:30, Mayayana wrote:
"Phillip Helbig (undress to reply)" wrote

| I've been using this to make thumbnails of jpeg files:
|
| for img in *.JPG; do
| echo thumbnailing $img
| convert -geometry 105x70 $img $img
| done
|
| Files from the K10D result in thumbnails of about 57 kB and those from
| the GR of about 46 kB, with little variation. Is there a simple
| explanation as to why?
|
| The K10D is 10 megapixels and the GR 16, but I don't see why that is
| relevant here, but maybe I am missing something.
|

Are the originals the same aspect ratio?
If not then you might be getting something
like a 105x65 and a 105x50. You also didn't
spec the compression level with the quality
parameter. (Assuming you're using ImageMagick
as Carlos speculated.)


Oh, I'm more than 95% certain :-)


Aspect ratio is the same.