Miscoloured subtitles again

Anything and everything to do with DCP-o-matic.
Anders M Olsson
Posts: 62
Joined: Thu Aug 04, 2016 12:24 pm

Re: Miscoloured subtitles again

Post by Anders M Olsson »

Just to make matters more complicated:

The results with DOM 2.12.4 and ClearType disabled does not look the same as 2.9.21. The newer version produces slightly darker grey pixels for bridging the border between the white core and the black outline, which gives the characters a slightly more jagged look.

In my opinion, the old version looks better! However, that's only based on my impressions on a computer display, not the projection in a real cinema. So things may look different under "live" conditions.

So what's the difference? Does the old version have its own internal font smoothing, while the new one uses some function in Windows?
Carsten
Posts: 2648
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Miscoloured subtitles again

Post by Carsten »

My suggestion to support antialiased burn-in subtitles was somewhere between 2.9 and 2.10, so, it may be that 2.9.x did not use ANY antialiasing, the only visible smearing being introduced by the J2K compression back then.

Now that I think about it, the idea to have antialiased font rendering may not even have been a particularly good one. Hard edges may help the chars to stand out and improve readability, just like an outline helps with that. At least as far as the char size /resolution combo allows. Most people would say that antialiasing will always produce a more pleasing image, but, maybe 'pleasing' is not a useful aspect here.

Let's see what Carl says, until then, we may produce some samples from 2.9, 2.10,2.12, and possibly at least with OS X and WIN7/8/10. Maybe at some time there will be a checkbox to enable antialiasing in appearance properties.

Again, I plead guilty for not being too concerned in general about subtitle appearance, as long as basic readability is there, and I usually prefer to use larger font sizes and outlining to achieve that.

- Carsten
carl
Site Admin
Posts: 2338
Joined: Thu Nov 14, 2013 2:53 pm

Re: Miscoloured subtitles again

Post by carl »

I'm not sure what changed but I'm just preparing a version which explicitly turns off sub-pixel AA (i.e ClearType) ... hopefully ...
Anders M Olsson
Posts: 62
Joined: Thu Aug 04, 2016 12:24 pm

Re: Miscoloured subtitles again

Post by Anders M Olsson »

carl wrote: Wed May 09, 2018 10:44 pm I'm not sure what changed but I'm just preparing a version which explicitly turns off sub-pixel AA (i.e ClearType) ... hopefully ...
Tested with version 2.13.22. (Bug fix: "Try to disable sub-pixel anti-aliasing (aka &lsquot;ClearType&rsquot;) when rendering subtitles.")

Sorry, but it didn't work. The miscolouring is still there, both in the preview and in the final DCP.
xyzzy
Posts: 12
Joined: Tue Mar 01, 2016 9:53 am

Re: Miscoloured subtitles again

Post by xyzzy »

Any updates on this topic?

Subs look terrible using 2.12.10, and disabling ClearType gets rid of the colouring but results in jagged edges instead.
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