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unmei
22nd November 2003, 21:28
Let me explain: i would like to implement ASS import and export in my program, but there are quite a few ASS features/switches that can hardly be translated to USF. Now i would like to know which of these are being used, in order to work out a way of preserving them somehow or at least handling the discard in a acceptable way.
My main points of interest are:
-layer: anyone creating ASS depending on different layers?
-drawing commands (\p ...): future USF specs might allow a transform of some these into shape elements, are they used often?
-animation like \t and \fade: could be used by creating a effect element and assigning this to the subtitle in future USF specs, would that be a suitable approach and does anyone use these features at all ?
-advanced font scaling with \fsc, \fsp : if used, what would be best approach to handle (ie use a uniform scale like modifying the font size) ?

I'm sorry i lack ASS experience pretty much and don't know what is important in ASS for people "in scene". However i would like to provide a good ASS -> USF conversion without making it unnecessary complex (the routine is damn complex already now ><)

Liisachan
25th November 2003, 12:38
Just for your information: I often use layers.
I sometimes (tho not often) use \p and \t
\fade is used very often, like {\fad(100,200)}
in short, everything in ASS is used more or less.
In case you need a real sample, here's a vid sample zipped with ASS source * (http://www.geocities.co.jp/MusicHall/2722/ass-sample.zip)

I hope USF will be something great, because SSA/ASS is a bit too windows-centric. But, seeing today's usf specs, conversion from SSA/ASS to USF is obviously NOT lossless, and so not that attractive....
How about adding something that you cannot do with ASS but you can do with USF :) such as "box model" like CSS, forinstance:

.note {
border: white 3px solid rounded-square(radius=3px);
background: #eee;
background-alpha: h80;
}

etc etc..... (too much to dream?)

bill_baroud
25th November 2003, 19:55
i think everything is used in ASS except (at least for me) the drawing functions.

unmei
25th November 2003, 20:25
thanks for your answers- gives me a push to refine this import module a bit more and to add the the mentioned features as possible.

@Lisachan:
i agree ASS->USF will probably never be lossless, but for SSA->USF i think i have already reached a acceptable preservation level. IIRC the only thing not preserved in the current build (on my HD ;)) is \fe which i will most likely never implement and i think it can be avoided by using unicode or utf-8 for SSA already.

If i understand correctly the proposed box model would be like a template combining a style with a readymade shape and ev. effect. I don't see how you could easily insert this in the specs like they are today but if someone manages i'll be up to implement it in u96 of course :) BTW its you being a member of the "specification committee", not me ;)

@bill_baroud:
this is pretty much what i could derive from Lisachans post and i think the drawing can only be implemented once the specs for <shape> are defined, i somehow see how it could become from the sample USF, but as shape is not currently in the DTD i did not touch it yet.

I'm thinking about sending a proposal DTD to toff one time which would make a first attempt to handle shapes and effects and also finally would include embedded files (which are probably not much used, but as i more or less implemented it already i think it would be time to spec it in order to fix the element names and attributes). The problem with my proposal DTD is, it only reflects my ideas and could be quite stupid in some areas, but i think its time for the USF to move forward a bit again. ATM i have no time, but next weekend i'll finally return to U96 and could then think about USF specs a bit more, also considering the box model/templates :). I think this could really be interesting, esp as i think drawing stuff is mostly used in relation with text, <shape> might even not be used anywhere execpt in templates.

Liisachan
1st December 2003, 14:49
come to think of it, the main purpose of USF is softsub, right?
then, I'd say we don't need full ASS features, because, it wouldnt't work nicely as softsubs anyway, unless you have , like 3GB+ CPU.

Recently I've realized we do need USF to make SSA-ish fancy softsubs x-platform (ie to make it work not only on windows but Linux Mac etc)

Defiler
1st December 2003, 18:48
I wouldn't want to see the format cut down to meet the needs of current CPUs, especially when those CPUs won't be current for long. $60 U.S. gets you a 2.4GHz CPU at the moment. Two years from now, with a fully-specified USF and various assorted tools, a basic processor should be plenty to handle all but the most complex soft-subbing tasks.
Speaking of the drawing commands.. are those possibly what L-E is using during the eyecatch of Galaxy Railways? (Am I the only one watching this show? Heh.)

unmei
3rd December 2003, 16:59
lisachan im probably the only person in the world doing so, but i make all my hardsubs with USF ( avisynth textsub() ). Of course, these are rather simple scripts as i don't do karaoke and i suspect i only do it because i han use my program in "field work" this way - anyway i spot most bugs by this "daily use", not when i explicitely run tests for the modules im working on.

And i agree with Defiler, USF should not be limited to stuff current CPUs can handle in real time. Because if we did, we weren't much farther than we were with SSA: the format will be too limiting in a few years.

Of course, a format that can produce softsubs more demanding than cpus can handle asks the author to take the responability to design the scripts in a way suitable for the target processors. But i think we can ask that from people, as encoders have to deal with this question anyway (hell, i'm thinking about my PIII 600mhz "playing" 720x576 PAL full res xvid with he-aac and similar issues :).

Is there some interest in USF in the linux and mac world ? i wouldnt know but it would be nice. I recntly had this dream of building a "lite" version of u96 in Java for cross-platform, but a) i lack time b) i doubt there are decoding facilities right now on these systems. --well: future project :)

BTW: i finally upped a new release on 2003-12-01
but bill baroud already pointed me at a couple of problems with ssa/ass import i will have to deal with.
Anyway the new release has 2 months of develing inside, there are lots of improvements and additions in all aspects of the program, not only import.

ChristianHJW
5th December 2003, 12:17
Originally posted by unmei Is there some interest in USF in the linux and mac world ? i wouldnt know but it would be nice. I recntly had this dream of building a "lite" version of u96 in Java for cross-platform, but a) i lack time b) i doubt there are decoding facilities right now on these systems. --well: future project :)

unmei,

in fact one of the main reasons that SSA/ASS is not yet supported on Linux for playback is that there are no editors available for Linux.

USF could fill this gap nicely with your editor, however i dont think its a good thing to make it based on java, because many hardcore Linuxers consider Java to be kiddies toys.

If i were you, i would try to make U96 x-platform based on wxWindows, like jcsston and Mosu are doing with their tools. Making x-platform capable software is admittedly not easy, but for sure a great training and will increase your 'market value' as a programmer significantly ;) ...

My promise : if you make U96 x-platform, i organize USF playback support on LInux, either via VLC or mplayer :) !