--- Forwarded Message from eric eubank <[log in to unmask]> ---
>In-Reply-To: <[log in to unmask]>
>References: <[log in to unmask]>
>Date: Thu, 10 Nov 2005 12:10:24 -0600
>To: Language Learning and Technology International Information Forum
<[log in to unmask]>
>From: eric eubank <[log in to unmask]>
>Subject: Re: #8082 Streaming QT: text tracks (!)
Hi - QT text tracks will not stream - they have to be loaded via
progressive download. But you can combine streaming media tracks with
text tracks.
And that resulting movie must be served via regular webserver, over
http. That is, you cannot serve it directly from the QT/Darwin
Streaming Server.
One method of creating a combined, streaming/QT text movie begins
with saving a reference movie from the streaming track to your local
computer. Enter the streaming URL in QuickTime Player Pro and then
save that movie (as self-contained).
The very small, resulting movie is just a pointer to the actual
streaming asset.
e.g., Open URL (cmd-U, ctrl-U) in QuickTime Player
rtsp://quicktime.laits.utexas.edu/itsaud/qe-0-01/Unit03part2.mov
and save as self-contained => a streaming reference movie.
A copied text track can then be added to that streaming reference mov
in QuickTime Pro: in text track movie => rewind select all, copy. In
streaming reference movie => rewind/"add scaled" .. a composite movie
can be saved from the combined tracks (again, saving as
self-contained).
One would assume that the text track is the same length as the
streaming track, to begin with; otherwise subtitles and streaming
audio/video would be out of sync. So in that case, no need for "add
scaled" .. just "add." In any case, to access the "add scaled"
command, in QT Player Pro/MacOSX, hold down the option key, while
pulling down the "Edit" menu.
After the composite movie is saved, it can be served from any old webserver.
Streaming and progressive download tracks will play together,
assuming that enough of the text track can download prior to the
streaming track beginning.
---
Here's an example of a (very long - 5hrs+) streaming audio track with
text tracks:
http://www.laits.utexas.edu/cid/qtl/all_stream_sub.qtl
There's another text track in this movie (a chapter track): it also
has to be downloaded first. So you can combine all sorts of tracks
and serve the resulting movie via http; but only hinted tracks can be
served directly from QTSS/DSS.
---
fwiw:
* with very long streaming tracks (guesstimate: an hour or so),
text tracks will drift out of sync.
* the above qt text/streaming audio movie was added because
we discovered in QT7 that very long progressive dl qt/text movies
crashed QT player and/or browser with QT plugin.
Which was why we converted the audio to streaming.
While this works OK (except for the drifting out of sync later in mov),
obviously, best performance will result from desktop playback.
So for very long movs, we've also added the option of
downloading qt/text movs for local playback.
* Quite a few changes in QT behavior were evident in QT7;
most resulted in problems appearing that hadn't existed in QT6.
The general conclusion is that, for some more esoteric QT uses,
QT7 is subject to more bugs (some of which have been worked out
in subsequent updates). The bottom line: increased, cross-platform
testing is necessary with some such solutions in QT7.
--
Eric Eubank <[log in to unmask]>
Liberal Arts Instructional Technology Services
University of Texas at Austin
At 11:57 AM -0500 11/10/05, LLTI-Editor wrote:
>--- Forwarded Message from Jorg Waltje <[log in to unmask]> ---
>
>>Date: Wed, 09 Nov 2005 21:33:46 -0500
>>From: Jorg Waltje <[log in to unmask]>
>>Reply-To: Jorg Waltje <[log in to unmask]>
>>To: Language Learning and Technology International Information Forum
><[log in to unmask]>
>>Subject: Streaming QT: text tracks (!)
>>In-Reply-To: <[log in to unmask]>
>>References: <[log in to unmask]>
>
>
>Dear Listlers:
>
>Another streaming problem encountered by yours truly:
>
>We have been using $E3Textation$E4 to subtitle some Quicktime files of German
>clips. We serve them over an OS X streaming server. When we add the text
>track (subtitle) however, it does not show up, although audio/video streams
>fine. When I try to redo the whole file so that the text track has a
>hinted track added to it, the whole file will not play.
>
>Que pasa?? It runs just fine from the computer HD -- Has anyone tried out
>QT with text tracks over a streaming server, please come to my rescue.
>
>Best regards, Jorg
>
>---------------------
>Dr. Jorg Waltje
>Associate Professor
>Director LRC
>Ohio University
>Gordy Hall 17 D
>Athens, Ohio 45701 (USA)
>
>Ph: (740) 593-2748
>Fax: (740) 593-0729
>---------------------
>
>
>
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> LLTI is a service of IALLT, the International Association for
>Language Learning, and The Consortium for Language Teaching and
>Learning (http://consortium.dartmouth.edu).
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>Otmar Foelsche, LLTI-Editor ([log in to unmask])
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