Using "One Step Noise Removal" applies a colour cast

[John-S]

Applying "One Step Noise Removal" applies a colour cast to the entire image. I am running X7 at the moment but the same problem was present in my previous version which was X4, when I had the same computer but a different monitor.

To best demonstrate the problem, create a small new file and fill it with a mid-grey (128, 128, 128) and then apply the One Step Noise Removal. A slight shift towards red should be evident. If the noise removal is applied several times the effect is additive and becomes more and more obvious. The attached file shows the result of applying the noise reduction 10 times to the mid-grey square.

Is this a known problem, and if so, is there a workaround or a way to prevent it happening?

Thanks for your help.

John-S.

[Jean-Luc]

Good catch !
It is a bug.
What happens is :
at each tool application, R and B values are increasing 1 unit (approx.) and G value is decreasing one unit.
R128 G128 B128 becomes R129 G127 B129
On next application (same image), the values are R130 G126 B130
I'll report it to Corel.

[John-S]

Thanks Jean-Luc.

Do you know if it's likely that there will be a bug-fix release for X7 or would that type of thing have to wait until X8?

John-S.

[Jean-Luc]

Thanks Jean-Luc.

Do you know if it's likely that there will be a bug-fix release for X7 or would that type of thing have to wait until X8?

John-S.

Hi John-S,
I'm not working for Corel...

But I think there will not be a new Service Pack for PSP X7.
As it is a very old bug (exists on previous versions too), it means no one observed the defect before. Or, in other words, not many users have problem with this defect. If Corel corrects the problem, they will not gain users. They calculate how many money it costs to correct a bug and how many NEW users they will have after the correction. In the actual case, I think not many new users. And they will not lose users too.
But perhaps the bug is easy to correct and could be corrected in a future version. Who knows ?