Hi,

I may have discovered a bug in Inkscape when using Mac. I would like to check with other users first before filing a bug report. 

I noticed that, when I import a PNG file into an Inkscape document on my Mac, it creates a very thin black and white dotted border around the imported image. It becomes more visible after shrinking the image. Unexpectedly, the border is not visible when I open the same file from a different computer, which is running Ubuntu (20.04 LTS).

Please see below for steps to reproduce the problem, system information, two images demonstrating the problem (and its absence on a different machine).

Cheers,

Michael

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Steps to reproduce the problem:

1. Open Inkscape on Mac (after a fresh install) and open a new default document.
2. Take a screen shot by pressing  Apple+Shift+3.
3. Drag PNG file of that screen shot into the Inkscape document, accepting all default settings in import option window.
4. When zooming in, the dotted line is already visible on the horizontal borders, i.e., top and bottom borders.
5. To see the borders more clearly, rescale imported image to much smaller size.

Actual behavior: Inkscape adds a thin black-and-white border at the top and bottom border of the imported image. Opening the same SVG file on Ubuntu 20.04 does not show the border artifact.

Expected behavior: Inkscape imports only the image without creating any border around it. The Inkscape document should look the same irrespective of what OS is used.

My system:

• Model Name: MacBook Pro
• Model Identifier: MacBookPro18,4
• Chip: Apple M1 Max
• Total Number of Cores: 10 (8 performance and 2 efficiency)
• Memory: 32 GB
• System Firmware Version: 7459.141.1
• OS Loader Version: 7459.141.1
• Serial Number (system): PD9465GXHX
• Hardware UUID: 79066EFB-CF02-5913-B8B0-8741AEF4DD59
• Provisioning UDID: 00006001-001409840A02801E
• Activation Lock Status: Disabled

Before proceeding further, I'd reset the preferences, relaunch inscape and re-test

Sure! I just reset the preferences on the Mac, relaunched Inkscape and imported another screen shot. The border artifact is still visible.

Thanks,

Michael

M1 Mini Mac user here, on Monterey 12.4, 16gb RAM, everything runs as expected.

  Nome modello: Mac mini

  Identificatore modello: Macmini9,1

  Chip: Apple M1

  Numero totale di Core: 8 (prestazioni 4 ed efficienza 4)

  Memory: 16 GB

  Versione firmware di sistema: 7459.121.3

  Versione caricatore sistema operativo: 7459.121.3

  Numero di serie (sistema): 

  Hardware UUID: 35A24A21-ADBA-5B16-97C9-FEFD369D27E8

Hi Marco! Thanks very much for giving this a try. A colleague of mine was able to reproduce the problematic behavior that I reported. He uses the same computer as I do. It is strange.

I have recently seen a similar looking artifact on some image-patterns.

I'd try turning off Dithering in the preferences. Can't hurt to try.

Sorry for the late reply. I have tried it and it seems to work on Mac. I do not know why this is but the artifacts appear to be gone. I guess I will not file a bug report then. I will spread the good news. Thanks!