I noticed while watching a HDR10 UHD rip of The Godfather on the Vero 4K (March 2022 update) that the PGS subtitles are displaying dark grey instead of their proper gold colouring. The gold is intended to replicate the look of the original theatrical subtitles so it’s a shame to see them in this ugly grey.
I’m sure this is related to the feature request to lower the brightness of subtitles when in HDR mode but is there a way to disable the feature and bring back the subtitles’ original colour?
I’d guess that neither Kodi nor OSMC is changing the color of image based subtitles. Are you sure that the PGS subs on your particular file are golden? I’d suggest playing that file with VLC and check the color.
I just noticed this too. Via disc from my Panny UHD player with a full HDR chain, the forced subs are a golden colour. But via the Vero, the colour is wrong, but the font is correct. I looked at Kodi on a Shield and it also had the wrong colour, but the display was SDR. I noticed that on my blu-ray rip of The Godfather the Vero is showing the subs in their correct colour, so it’s the HDR source that seems to be tripping Kodi up?
Sorry for the delay in coming back to this. Unfortunately I wouldn’t have any idea how to create a sample short of sharing the entire rip. I did notice something else regarding this problem if it helps; that the subtitles don’t appear grey in every scene.
In the night-time scene where Luca Brasi visits the Tattaglias, the subtitles appear in their correct gold colour. It’s during the daytime scenes in Sicily that they turn dark grey. It’s as if Kodi is somehow ‘intelligently’ adapting the appearance of the subtitles based on the brightness level of the video. Is this a thing?
Can I ask if this video has just static metadata (HDR10) or dynamic (HDR10+)? The subtitle track needs to be merged into the main video stream. AFAICT it’s not possible to send the two streams separately via HDMI. Whether the colours are right or wrong, they shouldn’t change unless the display is applying some dynamic tonemapping, either because the video has that (HDR10+) or by some internal algo.
So I had a look at those Godfather clips. What I see is the SDR one has a yellow cast relative to the HDR one. The character doing most of the talking - his jacket is yellowy in SDR, a more realistic grey in HDR. So the differences in the subtitles seem to be general throughout the picture.
But here’s the thing - the difference is the same whether I play both from Vero on an HDR display, both from Vero on a SDR display or both on my HDR Panasonic TV from disc (UPnP). The TV can’t actually render the subtitles but the differences in the jacket colour are very similar.
I don’t have a Blu-ray player or any discs so can’t verify what you see through the Panny player. I’m not sure how we could proceed.
thanks for looking. When comparing vs disc playback it’s quite obvious that Kodi is getting the sub colour wrong, as the UHD disc gives a similar yellow/gold colour to the forced subs as you get with the bluray version. Kodi renders the sub colour correctly via the bluray mkv but not via the HDR version. Not a big deal I suppose, but it is somewhat jarring in places (e.g. the scene in Godfather II where Vito’s mother begs for him to be spared, the Kodi subtitles do look rather ugly compared to the disc-rendered version).
The scene I shared where Luca Brasi meets his demise does indeed have an excessively warm grade on the bluray version, which is much more natural on the new UHD. But the UHD forced subs are full grey via Kodi, not even close to disc playback yellow. I looked again at the early flashback scene in Part II where the boy Vito is taken to the villa of Don Ciccio, and here the grade is very close to my eyes between the UHD and bluray versions (though the resolution improvement on the UHD version is substantial). Here too the Kodi subs are grey, whereas the disc-rendered subs are yellow.
All I’m saying is somewhere in the video chain the subtitles are merged with the main video stream. From that point on, any adjustments made to the colours (eg YUV-RGB conversion in the display) are applied equally to subtitles and main video.
I’m trying to find out exactly where that merging is done and in what colourspace. Also trying to find out if it’s possible to determine what the subtitle colours are supposed to be. Tried SubtitleEdit to see if it adds the colour to the .srt it produces. It doesn’t (and its OCR is crap).
Another observation: with those Godfather clips I get the same differences with Kodi on Windows. Has the issue been raised on the kodi forum?
I’ve never found a (free) OCR solution that really delivers. SubtitleEdit uses Tesseract and I was surprised how many mistakes it made in those few subtitles in the Godfather clip. The best I’ve found is the way Google can take a scanned text pdf document and deliver searchable text. No idea if that technology can be harnessed in subtitle conversion, if that’s what you are after.