Legacy ImageMagick Discussions Archive

Hi!

I wrote a bash script that draw borders around images. But, after executing set of commands, image quality get much worse. Script is:
Results:

Original:
http://img128.imageshack.us/img128/812/ ... t01ig5.jpg

Result (much worse, look for example at red colored parts of image)
http://img505.imageshack.us/img505/171/ ... t01hy0.jpg

Can I do something here to retain image quality and get borders like that one?

Thanks in advance,
Ivan

I would say your problem is jpg compression. You can set the quality to 100 ? as the standard for jpg is 85 ?

Also try either reading your image in once and do all the modifications or save the tempory files to png format.

I think Anthony has some custom border examples on his site that may work http://www.imagemagick.org/Usage/crop/ but you will have to find them.

Although it also looks to me like high jpeg compression, I think, jpg -quality setting is not an issue, because, original and bordered photos are set to -quality 98 (I read that in GIMP). Also, resulting photo is bigger than original in kbytes.

I tried to make all borders in one line, and result is unfortunately same like before

Still I'm not sure why would I use png format? Isn't it very limited in number of colors? Do you meant tif instead of png?


Thanks for help!

It does just look like JPG image compression, it is JPEG image compession.

For other non-loossy image formats you would have no problem.

Setting a -quality to 100% helps but does not solve this problem.

The only solution is. Never use JPEG for intermediate processing of images!
Best format is MIFF, though if you like a more normal intermediate format PNG can also be used.

OK, thanks, I will try to avoid .jpg format for intermediate steps.

I would also preserve the original image, as a starting point for future image modifications. Or better still start with (and preserve) the most original versions of those images you have.