[Laszlo-user] H.264

Michaela Merz mm at michaelamerz.com
Wed Apr 21 06:08:46 PDT 2010


.. well, yes, I am sure Adobe or other CDNs have some kind of that
technology. But I ain't got the bucks to buy that stuff. Can't be too hard
to implement a solution into OL.

Here's what I have done so far:

Converted a video into 10 second h.264 chunks ("At war with the Army",
starring Jerry Lewis)

Created 4 mediastream with videoviews. All of them get a URL for a chunk
of video (1-4). Set audio to mute and set all mediastreams to play for
about 100ms - then pause them. That should trigger the download of the
video chunks.

Now we make mediastream 1 visible and play its content. Somehow I can't
hide the others, so I just set their heights to 0.

As soon as play-duration reaches 9.8 seconds, I start the next mediastream
and stop, close the previous. It will be hidden (set heigth to 0) right
away. A second into the play, I trigger a preload for the now empty
mediastream.

And the game continues round-robin.

Problems: The newly started videostream freezes for 1/2 second or so. It's
hard to find the exact moment to stick the streams together. Maybe there's
a way to manipulate the mediastream's buffer directly?

Michaela


> Have a look at Adobe Stratus:
> http://labs.adobe.com/technologies/stratus/
>
> Sebastian
>
> 2010/4/21 Michaela Merz <mm at michaelamerz.com>
>
>>
>> Thanks Sebastian. But that's not exactly what I am looking for. I'd like
>> to use HTTP-Streaming with 'chunks' of video distributed or cached
>> within
>> a cloud or P2P network.
>>
>> In other words: The video gets it's first 10 seconds from HTTP-Server 1,
>> the next 10 seconds maybe from HTTP-Server 2 and so on. This allows to
>> widely distribute a video without the bottleneck of a single server.
>>
>> Michaela
>>
>>
>>
>> > Hi Michaela,
>> >
>> > you can stream h.264 with Red5 and dynamically seek to the position in
>> the
>> > stream.
>> > That way you do not need to download any data at all.
>> > Or you use pseudo HTTP-Streaming with CUE-Points, that allows seeking
>> > also.
>> > For example with LightHTTPd, see
>> > http://blog.lighttpd.net/articles/2006/03/09/flv-streaming-with-lighttpd
>> >
>> >
>> > Sebastian
>> >
>> > 2010/4/21 Michaela Merz <mm at michaelamerz.com>
>> >
>> >>
>> >> Hi Sebastian et al:
>> >>
>> >> Thanks. I though so but I had a few failures with h.264 videos.
>> Turned
>> >> out, they were still packed within an MPEGTS envelope.
>> >>
>> >> Anyway. I am trying to programm a video player that supports
>> segmented
>> >> video clips. In other words, I am playing a 10 second clip while the
>> >> following clip(s) are downloaded.
>> >>
>> >> I am trying to get this done by using multiple
>> mediastream/video-views
>> >> each gets it's URL set and is paused after 100ms.
>> >>
>> >> I am than switching to display the different videoviews. This however
>> >> leads to freezing or 'sound only' after a while - so, I guess I still
>> >> have
>> >> some work todo :)
>> >>
>> >> Does anybody know, if this has been done before? Or is there a better
>> >> way
>> >> to preload data to be used in a mediastream/videoview?
>> >>
>> >> Thanks.
>> >>
>> >> Michaela
>> >>
>> >>
>> >> > Hi Michaela,
>> >> >
>> >> > why not? It does not depend on OpenLaszlo to support h.264, no
>> matter
>> >> if
>> >> > Live or VOD.
>> >> >
>> >> >
>> >> > Sebastian
>> >> >
>> >> > 2010/4/21 Michaela Merz <mm at michaelamerz.com>
>> >> >
>> >> >> Hello Everybody - it's me again.
>> >> >>
>> >> >> I searched Google but didn't find a usable answer. Does OL support
>> >> h.264
>> >> >> in the videoview?
>> >> >>
>> >> >> Thanks.
>> >> >>
>> >> >> mm.
>> >> >>
>> >> >>
>> >> >>
>> >> >
>> >> >
>> >> > --
>> >> > Sebastian Wagner
>> >> > http://www.webbase-design.de
>> >> > http://openmeetings.googlecode.com
>> >> > http://www.laszlo-forum.de
>> >> > seba.wagner at gmail.com
>> >> >
>> >>
>> >>
>> >>
>> >
>> >
>> > --
>> > Sebastian Wagner
>> > http://www.webbase-design.de
>> > http://openmeetings.googlecode.com
>> > http://www.laszlo-forum.de
>> > seba.wagner at gmail.com
>> >
>>
>>
>>
>
>
> --
> Sebastian Wagner
> http://www.webbase-design.de
> http://openmeetings.googlecode.com
> http://www.laszlo-forum.de
> seba.wagner at gmail.com
>




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