Carsten wrote:But, as a sideway, couldn't you just adjust the color (less green) to get what you want? After all, it's personal choice anyway. Yes, of course, white should be white, grey should be grey, but for now....
That was my thought as well. So I tried adjusting the color for less green, producing a magenta/pink looking subtitle in the preview window. But after creating the DCP, the subtitles turned out blue this time...
The subtitle colors seem to be completely unpredictable...
Perhaps with a lot of experimenting, it's possible to find some setting that produces neutral white/gray subtitles. There are less than 17 million combinations to try. Or it might be computed with some expert knowledge of the math behind the conversion...
Hmm. That's weird. I guess Carl has to look into this again. One should do some tests with a range of colors. I wouldn't care so much for colors, but clearly greys and white should render neutral on screen. Did you try earlier versions as well?
Hmm, interesting - I just did another test with a white background (RGB), this time with color conversion disabled. So DOM would assume the still image to be in XYZ/2.6. I burnt in 255,255,255 subtitles, rendered - and as expected, the resulting MXF appeared reddish due to the missing color transform.
However - the subtitle insert had the exact same color as the background - but it shouldn't.
Because DOM should apply the subtitle color transform separately from the source footage, it should always use an RGB->XYZ transform for burn in subs.
It looks as if DOM applies the same color transform to the burn-in subtitles as it does for the underlying footage???
Carsten wrote:Hmm. That's weird. I guess Carl has to look into this again. One should do some tests with a range of colors. I wouldn't care so much for colors, but clearly greys and white should render neutral on screen. Did you try earlier versions as well?
- Carsten
The earliest version I've tried at this time is 2.9.0, and as far as I can tell, all versions in the 2.9-series have the same problem.
Several months ago, I tried to burn in subtitles on an existing DCP. I no longer remember the DOM version number, but the entire picture turned red every time a subtitle appeared on screen. Since the results were clearly unusable at that time, I dropped the project.
Now my need for burnt-in subtitles has re-emerged, so I decided to give it another try.
All I know at the moment is that it should work; there is code specifically to cope with the case when you have a XYZ image and you are blending RGB subtitles on top: the subs are converted to XYZ before being blended.
I will investigate, but it may not be for a few days.
Do you mean burnt-in to the DCP, or do you mean bitmap subs from e.g. a DVD/VOB? Bitmap subs can only be changed in general size, position, and color. With XML/SRT, etc. sources, you can set outline width for burning-in. This is also reflected in the preview.
Or it might be computed with some expert knowledge of the math behind the conversion...