[magick-users] RE: Offering My Imagemagick Scripts

[Fred Weinhaus]

>Hi Fred,
>Do you know how 2 / have a script to fix quality of a jpg image after it's
>being enlarged (e.g. resizing a 100x100 image to 400x400) ?
>Thanks,
>S.


Hello S.

Sorry, but I am not sure what problem you are having. When you have a 
jpg image, it has already lost some quality, which cannot generally 
be recovered. When you resize it, you lose some more quality 
depending upon which filter option you have used. If you resize it to 
another jpg, you lose even more quality depending upon the quality 
setting. The best you can do is start with a non-compressed image 
format, such as png. (It does not help at this point to convert from 
your jpg to png, you need an original uncompressed image). Then when 
you resize, use -filter lanczos (which I believe is the default), but 
make the output format png or some other non-compressed image format.

That is the best that I can do to help. I know of no way to get back 
the losses from a jpg compressed image.


Fred