What does the Project X colours.tbl actually do to the subtitles?

https://sourceforge.net/projects/project-x/

I import DVB .rec files from my Topfield TF5100PVR Masterpiece PVR/DVR (Personal/Digital Video Recorder) to the computer.

I then author the .rec as a video-DVD with iTV2DVD with the converted DVB subtitles (or teletext subtitles) and chapters at 10 minute intervals.

http://users.tkk.fi/spotinka/itv2dvd/

Our local TV channel recently changed its DVB subtitle color tables. So now the converted subtitles are not so good as they used to be.

Project X (in iTV2DVD) uses colours.tbl when demuxing the subtitles form the DVB. Currently the best table is as follows but it still has some artifacts:

table=YLE2
model=4
0=0
1=FF010101
2=FF010101
3=FF010101
4=FF010101
5=FF010101
6=FF010101
7=FF010101
8=FFD0D0D0
9=FFD0D0D0
10=FF010101
11=FF010101
12=FFD0D0D0
13=FFD0D0D0
14=FFD0D0D0
15=FF010101

I haven't found a definite guide what those lines actually do. This is what I do know:

- model=final colour link depth of this table in bits (2, 4, 8) (means max. 4, 16, 256 paletized colours, best value depends on broadcasters std. table)

- 0..x=ARGB (alpha,red,green,blue as 32bit uimsbf, 8bit each) (undefined colour links are fully transparent). For example FF9C9C9C means:

FF hexadecimal alpha channel = 255 decimal opaque color
9C9C9C = 156 156 156 for RGB mid-gray

0=0 nonvisible title background

But what do the other lines do?? I suspect that lines 1-7 might affect the font's edges (outline outer edges vertical, outline outer edges corners etc or something like that...) and lines 8-13-15 the font's body.

Any info would be greatly appreciated because by trial and error I can't fine-tune the output.

thanks,

- Matti