titles and subtitle making and mixing to mpeg files

[jp80]

is there a way to edit completely at will subtitles police, size, and color, like professional software as Picture it and Paint shop pro do, and mix them quickly with mpeg movies, to add for example still or animated opening and ending titles, or karaoke subtitles DURING a mpeg movie sequence, without altering its original quality?

[LigH]

In DVDs, subtitles are stored as RLE compressed bitmaps in a private substream. They can have up to 4 different and independent colors and opacities (where one of them is usually transparent {the whole background}, one is nearly white {for the text body}, another is black {for the text border}, and the last could be used e.g. for a little anti-aliasing or extra color effect). It is possible to change color and opacity values frame by frame. With a professional DVD authoring application, you can place them over the MPEG2 video stream, and every consumer or software DVD player shall be able to overlay them over the playing video.

But I quite doubt that you will be able to produce DVD content professionally at home... I don't know how powerful a filter like DirectVobSub currently is, and how it could be synchronised with MPEG playback - if you want to create MPEG1 video, you will most probably have to render the subtitles into the video material; I don't know currently of any other working solution.

[guillep2k]

I've been talking to people from a Hollywood studio and they told me that there's no professional product that could achive something like that. They're starting to use free software to achieve that kind of results. In particular, they trying with Sub Station Alpha (http://www.eswat.demon.co.uk/substation.html) + MaestroSBT (download from Doom9's (http://www.doom9.org/) site). Sub Station Alpha is aimed for VHS subtitling with a dongle device, but is one of the finest editors around and has a powerful script design. MaestroSBT renders the SSA files into files readable from Scenarist (the most popular product used for DVD authoring, AFAIK). In MaestroSBT I tried to deal as fairly as possible with DVD format limitations, which are many. This method is not quick at all, though. BTW, if you meant SVCD, then the procedure is exactly the same but the last step (submux/I-Author instead of Scenarist).

The people at the studio made some tests to try out animations, but they seem to freeze most software and stand-along players (DVD subpictures are not intended to do animations).

Hope this helps...

Guille

[LigH]

Originally posted by guillep2k
...DVD subpictures are not intended to do animations...


Yes, that's true... although it is indeed possible to change the subpicture for each frame, it will be impossible to create a very complex "cartoon" - because the process of reading and decoding the subtitles might take longer than the time allowed to display it. Big and complex subpictures might become so big that they need to be spread over several video frames to stay below the maximum allowed overall bitrate for DVDs.

From my experience as a former DVD author, I can report: For example, it was possible to create a countdown with tenths of seconds in one small corner (2 to 3 frames per animation frame is enough for simple structures in small areas); also, it is possible for consumer players to change colors and transparencies per each frame (maybe not for software players); instead, big and complex subtitles masking the whole screen could not be switched from one frame to another (the DVD player needed more than one frame time to decode the next subpicture, and blanked it for this frame duration).