Re: [Gimp-developer] Purple fringing removal extension

[Martin Jambon <gimp mjambon com>]

On 07/14/2012 01:51 PM, Monty Montgomery wrote:
> On Sat, Jul 14, 2012 at 4:35 AM, Martin Jambon <gimp mjambon com> wrote:
>> Hi,
>>
>> I am totally new here but I wrote a standalone program that does a
>> decent job of removing purple fringing from photos, and I would like to
>> be able to implement the same functionality for Gimp.
>>
>> Here are some examples of what it does:
>>
>>   http://mjambon.com/purple-fringe/examples.html
> 
> Hey, that's not half bad.  I especially like that it doesn't go
> overboard trying to 'fix' everything completely, just makes a nice
> solid improvement.
> 
> Do you have any examples that show it not working well, or doing
> something unexpected?  For example, a camera where the fringing is a
> slightly different hue due to a slightly different Bayer filter, or a
> different UV cutoff?

It requires manual tuning when purple objects are present, otherwise the
default settings would often grey them out. The purple areas in the last
example at http://mjambon.com/purple-fringe/examples.html would become
completely black with the default settings.

I am sure there are many ways to improve the results but before digging
deeper, which can last forever, I would like to create an initial Gimp
extension.

> I would Totally Use This, especially given my fondness for vintage
> lenses that can fringe badly.

Good to hear!


Martin