Photos and Slideshows

Kodi
1

Hi there :slightly_smiling_face:,
I am the proud owner of an AM6B Plus since 3 months, and I have been following this forum since before as a reader. However, I haven’t found an answer to my question.
I have a Philips OLED 77 4K TV and the DV / HDR rendering is excellent with this box.
However, I have a small problem with photos and slideshows.
I use the box because when I start a slideshow, the advantage is that it reads my videos at a very high bit rate as well as photos, which the TV doesn’t support very well.

The photos have a resolution of 4000x3000 (4:3).

Problem 1 - Image sharpness
If I view my photos via a USB key directly on the TV or via HDMI on my PC, the photos are sharp on my TV. Of course, there are 2 black bars on each side, since the TV is in 16:9 format.
With the AM6B Plus box, the pictures are not sharp.
I’ve tried enabling/disabling downscaling in the box settings, but it doesn’t make any difference. I’ve also tried changing the GUI resolution, which obviously plays no part here. I should point out that I use the same mode on my TV for each test (which is as neutral as possible - manually calibrated according to FlatpanelsHD).

Problem 2 - Picture color
With exactly the same colorimetric profile on the TV, when I view my photos via USB or HDMI from my PC, the color is good.
When I watch with the box, the colors are so bland that I have to use another unnatural colorimetric profile that “over-saturates” the colors (which I normally hate, but in this case makes it possible to obtain more or less acceptable images).

Attached is an image (nothing exceptional - made with a Samsung S23 in automatic, slightly oversaturated, and the blacks are poor).
When I look at this image via the AM6B box, the texts on the car doors are “crusched”, and the colors are absent…
Edit : the picture becomes apparently compressed when uploaded to the forum.

Many thanks for your help ! :hugs:

20250311_115936
20250311_1159361920Ă—1440 311 KB

2

Best is to try Kodi from another platform and compare if same issue happen.
If yes, this is the place to go: GitHub · Where software is built

3

For #1 - Image scaling in Kodi is notoriously not great. I believe that Kodi 22 has some new work on this issue, but it’s not clear to me if it will help the Pictures side of things on Amlogic hardware or not. But worth a try if you’re using Kodi 21 currently…just try a separate install on a USB with Kodi 22, as a test, maybe.

The best solve I have found is to just export a dedicated library for Kodi at the appropriate res (so fit to 1920x1080 basically). This avoids any scaling, giving the sharpest results. You’d think using a scaling factor of 2:1 would also result in equally or nearly equally sharp results (so using images fit to 3840x2160) - but it doesn’t, the results are distinctly less sharp than with 1:1.

4

Good evening,

Thanks for the feedback. :slightly_smiling_face:

Regarding #1, in a few rare cases, the “High quality downscaling” setting may help a little. However, in other cases, the image becomes almost too blurry, so this option should be avoided I think.
The situation I’m facing is a pure aliasing problem actually (staircase effect).

@bossanova808 thanks for the tip ! I’ll try your suggestion again later, but it makes sense!

Regarding #2 and the color, I’m the guilty. Kodi displays colors correctly. I’m still discovering the world of colorimetry… sorry. I had calibrated my TV to get the most natural image possible for movies (so a warm temperature). In the case of photography, we’re actually looking for rather cold temperatures, not a warm ones!

I’ll be doing some more tests over the next few weeks/months regarding #1. I’ll let you know if I notice any changes with the new version as well.
Thank you and good evening