User Defined Filter makes layers transparent

[Zacabeb]

There's a bug in the User Defined Filter where it performs incorrect calculations and alters the alpha channel of the layer under some conditions. I've already contacted Corel support about this, but am curios if others get the same result.

So here's some steps to replicate the issue.

1) Create a new RGB image and fill it with black.
2) Draw something in white in the middle of this image with a fine, sharp brush.
3) Make sure the layer is a background layer. If not, select merge layers to make it a background layer.
4) Open the User Defined Filter and enter the following coefficients to produce a simple high-pass filter:

Code: Select all

  0  0  0  0  0  0  0
  0  0  0  0  0  0  0
  0  0  0 -1  0  0  0
  0  0 -1  4 -1  0  0
  0  0  0 -1  0  0  0
  0  0  0  0  0  0  0
  0  0  0  0  0  0  0

Divisor: 4
Bias: 128
R, G, B: All checked

5) Click OK to apply the filter.

The result should be a gray image with outlines around what was drawn in it, which is the desired result.

6) Undo the last step to return to the image as it was before.
7) Now turn the background layer into a raster layer; either use the Pick tool and click on the image, or double-click the background layer in the layer palette and click OK in the dialog.
8) Open the User Defined Filter again and apply the same settings as in step 4.
9) Click OK to apply the filter

The resulting image will now be transparent with faint black outlines, which should not be the case. The filter should not affect the alpha channel at all, and there should be both bright and dark RGB values in the outlines.

This does not happen if one of the RGB channels is deselected when applying the filter, or when the coefficients in the matrix add up to a big enough positive value.

I observed this in both PaintShop Pro X6 and PaintShop Pro 2021, but not in PaintShop Pro 9.

If others can replicate this, please feel free to file a bug report with Corel so that they might take some interest in fixing it. The filter I've shown in the example above is exactly the kind of stuff the User Defined Filter is designed for, and it being broken like this makes it almost pointless. A workaround is to apply it twice; once to only two of the RGB channels and once again to the remaining channel, but that kind of workaround shouldn't be needed.

Edit: Clarified some of the steps.
Edit 2: Clarified some of the steps further to avoid confusion (I wrote the post in a bit of a hurry...)

[Jean-Luc]

Could you verify your steps?

The result should be a gray image with outlines around what was drawn in it, which is the desired result.

On my side, in PSP 2021, the result is a transparent image and not a grey image. The faint black outlines are visible.

7) Now double-click on the background layer to promote it to a floating layer.

Double-clicking on the background layer opens the Layer Properties and not a floating layer.

[Zacabeb]

Could you verify your steps?

Fixed it. Thanks for the heads-up.

[Jean-Luc]

Fixed it. Thanks for the heads-up.

What did you fix?
Is it a bug or not?

[Zacabeb]

Fixed it. Thanks for the heads-up.

What did you fix?
Is it a bug or not?

I meant that I fixed my list of steps to reproduce the bug.

[LeviFiction]

I can duplicate. Also, kind of fun, locking the layer transparency turns it white.

Side Note on your instructions:

EDIT: I was wrong here, I'm editing my response to remove the wrongness though a portion of it is quoted by Jean-Luc below.

On Step #7, I'm assuming you're clicking the canvas with the pick tool and promoting it to a raster layer. And not creating a Floating selection layer. This should probably be changed to "Promote the background layer to a raster" and let the person following the instructions choose the method they want to use to perform this step.

[Jean-Luc]

So I'm very confused as to why you'd have a selection active to perform step #7.

In your steps, you never said you made a selection.

[LeviFiction]

Never mind, Jean-Luc. I was wrong. I don't think they were working with selections. I was working off of their description and making assumptions. The description of double clicking and making a floating layer made me think of using selections. But they could just be using the wrong words.

If you don't focus on the floating layer, and assume they mean Raster layer. Promoting the background layer just makes it a raster it doesn't float it and it doesn't duplicate the layer. I just promotes the layer. And they do use the word "promote". If they have the pick tool active they just need to click once on the canvas and PSP will auto-promote the background layer to a raster layer. They probably double-click out of habit assuming that's what's necessary.

The part that reaslly confused me was they mention hitting "OK' to convert the layer after double clicking. I only see that if I use the context menu and choose "promote layer". But that's easily soloved, if you go into your preferences and change "Promote to full layer" to prompt you then you single/double click with the pick tool it'll ask if you want to promote the layer.

Long explanation to say, I was wrong about the selections. I think they just used the pick tool and clicked on the canvas to promote the background layer to a raster layer and have PSP prompting them for permission.

[Jean-Luc]

5) Click OK to apply the filter.

The result should be a gray image with outlines around what was drawn in it, which is the desired result.

I'm following your steps and after 5), I don't get a grey image but a transparent image with outlines around what was drawn. I'm missing something?

EDIT: sorry, I was wrong. I see now the grey image. Will continue to test...

[Zacabeb]

Thanks for the help so far. I've made some changes to my original post to hopefully make it a bit clearer.

[Zacabeb]

Update: I got a response from Corel's outsourced customer support. It wasn't very helpful, as they wanted to remote control my PC to see the issue. I've responded with a full bug report and asked them to forward it to the development team. But I don't expect them to do so to be honest.

[hartpaul]

So I'm very confused as to why you'd have a selection active to perform step #7.

In your steps, you never said you made a selection.

This why I use the word 'Choose' to avoid confusing with the word Select and Selection.