How they do that? (subtitles anf audio language)

[vinhwng]

My ISP ADSL have a web page to see the film onlne. when the film playing (by WMP9)i can change subtitles( English and Vietnamese), and audio language( English and Vietnamese). In my PC no need request install any software or plugins. How they do that? How my seft creat the same this project. Hlp me pls. Thank u very much. (sorry because my engl. very bad :)

[unmei]

Welcome to the forum.

Since you say it doesn't need software, i guess it is not some sort of mpeg-2 systems trick to switch the tracks (people would at least need DVD playback software ..i'm not sure but i believe windows still comes without by default). But rather they effectively switch the entire video, like, they have 3 (or more) separate videos on the server (V, E, E+v, ..) and when you select another option you get a completely different file streamed to you.
Another possibility were the use of something like SMIL metafiles (i AM sure M$ has its own implementation, i just don't know it).

When you switch audio/subtitle is there a delay until the new cofiguration picks up? This is interesting because if the delay is almost inexistent, they probably send you all the tracks all the time (broadcasting) and the switching happens on your side, if the delay is remarkable -let's say a second or more- most likely a request is sent back to the server to send you a different stream now.

[vinhwng]

to unmei
thk for u hlp.
but idon't think so. because :
1. they (ISP) have server about 1000 movie, with bitrate 1600kbps, average 1 hour play they lost 1gb space harddisk, if 1 movie they have 3 film for 3 language, they must have very big server, i think that is not good solution.

2. the subtitles very sharp, they same text file not a bitmap file.
not subtitles render to movie file.

u have another solution? help me pls!

i accept load any plug-in and third-party program to play avi,wmv on WMP9 with 2 subtitles (text format). and i can switching 2 language by WMP9 option

[unmei]

Now i thought you wanted to know how they do it, and not how it could be done..
anyway..

ok, they offer several movies. I this case you're obviously right, they can't be broadcasting them all (hmm 5Gbit line just for movies ..ADSL is limited to something like 8mbit i thought).

I never use WMP so i don't know exactly what all is possible or borked from normal direct show operation or what they added that is not normally available for direct show. Additionally i don't know what all WMV is capable as it is one more microsoft product i prefer to walk a long way around.

But what i can tell you is, it is not a mpeg-1/2 systems solution if you have text subtitles.
It could be a SAMI (*.smi) metafile (i looked it up - that's what i meant with M$ version of SMIL, just search msdn.com for it) This file would contain the text subtitles and (i think) allow for switching of audio used file. The other possibility is, the (one) video and (multiple) audio and subtitle streams are muxed into a single container file.
I know this kind of muxing is possible in AVI, but support for it is not too great (players may or may not allow you to play it or select streams).
I don't know whether it is possible with WMV.
I know it is very easy with OGM and MKV is almost "perfect" for this, but i doubt a big company like a ISP would use these formats right now. Also streaming with MKV (Matroska) is not proven to work.
It is also possible with mpeg-4, but the thing here is the text subtitle specification for mpeg-4 is barely a few months old - therefore i highly doubt there is a collection of 1000 movies with mpeg-4 text subtitles somewhere.

You see, i can't offer you a good solution i'd know of. You are asking for 3 things that are almost impossible to combine (1) for a wide audience - easy to use (WMP/almost no install). (2) streaming (3) multiple switchable audio/subtitle.

you can have (1)+(2) with quite a few commercial solutions (i bet)
you can have (1)+(3) with (OGM+OGGDS) or (MKV+Matroska) pack or (OGM or MKV and Media Player Classic)
you can have (2)+(3) by using commercial Quicktime, Real Networks or non-commercial Videolan Client/Server ..or probably also ready-made commecial MPEG-2 solutions (with picture subtitles then)

if you can reliably offer (1)+(2)+(3) you can probably gain a bunch of money

[vinhwng]

unmei, thank again
i think SAMI is very good solution to play WMV on WMP9.i just look for on msdn.com and found my answer.
this link for whom have a same problem :
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/wmplay10/mmp_sdk/aboutsamifiles.asp