Adding permanent subtitles to an existing SVCD (-image)...?

[Lukas]

I have a SVCD image file which contains no subtitles.
I have a matching subtitle file.

How do I "paste" the subtitles to the SVCD and burn a new one to watch? It must be permanent subtitles, since my DVD player do not support any SVCD-subtitle standards.

I assume that the process will be something like:

1) Extract .mpg file from image file (Isobuster?)
2) Sync subtitle file and .mpg file
3) "Paste" subtitles to .mpg file
4) Burn SVCD with Nero or similar

I have read a lot of guide on AVI->SVCD incl. subtitles, but none that addresses my problem (above points 2 & 3) in a way that I can understand it.

Can anyone please help a newbie..?

[Baldrick]

Use virtualdub-mpeg2 and add the subs and frameserve to tmpgenc and reencode.
https://www.videohelp.com/srtsubsvirtual.htm

[Lukas]

Thanks Baldrick!

It took me a while to understand that there is both VirtualDub and VirtualDub-MPEG2... and that I should use the latter.

Now my process is:
1) Extract .mpg file from image file (Isobuster)
2) Sync subtitle file (.srt) and .mpg file (I use Subtitleworkshop)
3) Convert .srt file to .ssa file with "SRT to SSA Converter"
4) Use VirtualDub-MPEG2 to start frameserving
5) Use TMPGEnc. to create the final .mpg file (Note: Make sure to select NTSC/PAL according to source .mpg)
6) Burn SVCD with Nero

I have one more question: The final .mpg file (including the subtitles) seems be be approx. 48% bigger than the original. I realise that I can control the file size in TMPGEnc. by adjusting (reducing) the "average video bitrate"... however I am not sure how much quality I loose, compared to the original .mpg file. Is there a trick to maintain high quality, or should I just
A) accept the bitrate suggested - to be able to stick to one CD
B) select the highest bitrate and split the created .mpg file and burn to two CDs
???

Thanks again!

Lukas