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IMatch Bug Reports and Feature Requests => Bug Reports => Solved Bug Reports (for next version) => Topic started by: ubacher on April 08, 2022, 08:12:48 AM

Title: [NR] Attached image shows banding ONLY in viewer/quickview
Post by: ubacher on April 08, 2022, 08:12:48 AM
I attach a jpg which shows banding in the lower left corner when displayed from within
Imatch. Outside of Imatch (photoshop, irfanview, photos, firefox) do not show this banding.

I did a screen snip of the left hand corner - also included. It shows the banding faintly
when displayed outside Imatch and clearly when displayed from within Imatch.

What bothers me the most is, since it does not show up in photoshop, I can not detect/correct it there.
( I just tried within photoshop to increase the contrast extremely and only then can I see faintly some banding
in the corner.)


Title: Re: Attached image shows banding ONLY in viewer/quickview
Post by: Mario on April 08, 2022, 08:54:34 AM
What file format is this?
When it is from a RAW, which codecs are installed, which RAW-related settings do you use in IMatch? WIC codec? LibRaw?
If this is a RAW, is the embedded preview large enough or has IMatch to use the WIC codec / LibRaw to develop the image.
Title: Re: Attached image shows banding ONLY in viewer/quickview
Post by: ubacher on April 08, 2022, 01:01:48 PM
It is a jpg file produced by photoshop.
Title: Re: Attached image shows banding ONLY in viewer/quickview
Post by: Mario on April 08, 2022, 01:43:17 PM
Thanks for the info. Would have saved some time.
Maybe a color profile issue? Or a monitor setting issue?
I will forward it to the company that delivers the JPEG encoder component used by IMatch. Unfortunately, this is all I can do. Their response time is months, usually.
I will also inform Microsoft that maybe the WIC codec for JPEG used by the Viewer in IMatch, or the DirectX codec IMatch uses to render your image with the help of the graphic card may have a banding issue.
They won't respond, probably.

Do you use an Intel graphic card?
Is this a Notebook?
Is the most recent driver installed?

This is how it looks on my machine in the Viewer: (100% screen shot, no banding at all, just some noise).
Title: Re: Attached image shows banding ONLY in viewer/quickview
Post by: ubacher on April 08, 2022, 06:55:46 PM
QuoteI will forward it to the company that delivers the JPEG encoder component used by IMatch.

This is the most likely cause since outside of Imatch the display is OK.  Not much more you can do -
and not a big issue - just curious.

(Nvidia display with newest driver on a desktop)

Any other users out there who checked this image on their system?
This would help to verify that it is not a hardware issue.
Title: Re: Attached image shows banding ONLY in viewer/quickview
Post by: Mario on April 08, 2022, 07:10:24 PM
I use NVidia cards and I see no banding. See my screen shot.
Title: Re: Attached image shows banding ONLY in viewer/quickview
Post by: frankdarwin on April 08, 2022, 10:04:45 PM
Quote from: ubacher on April 08, 2022, 06:55:46 PM

Any other users out there who checked this image on their system?
This would help to verify that it is not a hardware issue.

Yes. I checked the image on my end and saw no abnormalities.
Title: Re: Attached image shows banding ONLY in viewer/quickview
Post by: thrinn on April 08, 2022, 11:16:22 PM
I, on the other hand, see some banding in the lower left corner, not only in the Viewer, but also in the Quick View window. And also, which might be interesting, in Affinity Photo. But the effect is really hard to see. In Windows Photos it is also visible (at 100%). The attached screenshot is from Photos at 100% (only lower left corner of the picture). I have a Radeon RX 5500 XT graphic card.
I am still on Windows 10, by the way.
Title: Re: Attached image shows banding ONLY in viewer/quickview
Post by: frankdarwin on April 09, 2022, 03:18:02 PM
Addendum:

My equipment:

Graphic card NVIDIA GeForce GTX 1080 (HP) 4095 MB
Monitor: LG HDR WFHD (2560x1080@60Hz)
Windows 10
Title: Re: Attached image shows banding ONLY in viewer/quickview
Post by: Tveloso on April 09, 2022, 03:35:17 PM
I don't see the banding here either (just some very faint noise - when viewed at 100%).

I'm using:
NVIDIA GeForce GTX 1050
Asus MX25AQ Monitor (2560x1440)
Windows 11
Title: Re: Attached image shows banding ONLY in viewer/quickview
Post by: Jingo on April 10, 2022, 01:30:46 PM
Same for me.. all looks good on my system.. Win 10, Nvidea
Title: Re: [NR] Attached image shows banding ONLY in viewer/quickview
Post by: ubacher on April 11, 2022, 07:14:52 AM
For all who test his:
You must load the image into Imatch. The banding I see ONLY shows when displayed in Imatch Viewer or quickview.
Title: Re: [NR] Attached image shows banding ONLY in viewer/quickview
Post by: Mario on April 11, 2022, 08:33:42 AM
We did. I do. I also see the banding in Windows Foto. But not in IMatch. On two computers.
Title: Re: [NR] Attached image shows banding ONLY in viewer/quickview
Post by: sinus on April 11, 2022, 08:42:46 AM
I see no banding.

I looked at it side by side in photoshop and in the viewer of IMatch.
I personally see no difference.