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Jabberwock
01-18-2010, 05:33 AM
Hi,

I have to use a media server to stream some videos (tipically 720p) over a LAN and, for some clients (using WMP 11, tipically), I have to transcode the video streams to a lower resolution (these computers are old, so they cannot play 720p as is).... well, the problem is when I activate transcoding, the playing starts after a lot of minutes (if I use Generic device 1 as device profile: if I use any other Generic Device or WMP profile, it doesn't start at all)!

The server configuration on which I am running Mezzmo is:
AMD 4850e X2 (Dual Core 2.5 GHz), 2 GB RAM, Windows 2003 Server x64, 150 GB of free disk space!

I appreciate if someone can give me some advice. :)

P.S. Do you think you'll insert in Mezzmo any GPU transoding support?

Paul
01-18-2010, 08:49 AM
Hi,

Can you please turn on logging and then try to transcode one of those files again. After that, send us the logs to support (at) conceiva (dot) com and we'll take a look at transcoding speed, or if you wish, you can take a look at the transcoding log and see at what fps the files are being transcoded. Generally, if they are transcoded at less than ~25 fps, then the video won't play smoothly first time you try to play (while it's transcoding) because there won't be enough data to send through. They should play fine when you try them again in a few minutes though.

Regarding GPU support - Mezzmo uses ffmpeg for transcoding and since we use it as a separate, external process, you can substitute your own build of ffmpeg (with more format support, better optimized for your hardware, etc...) at any time. Please let me know if you need help building ffmpeg and I can give you some starting directions.

Jabberwock
01-18-2010, 09:44 PM
Hi,

Can you please turn on logging and then try to transcode one of those files again. After that, send us the logs to support (at) conceiva (dot) com and we'll take a look at transcoding speed, or if you wish, you can take a look at the transcoding log and see at what fps the files are being transcoded. Generally, if they are transcoded at less than ~25 fps, then the video won't play smoothly first time you try to play (while it's transcoding) because there won't be enough data to send through. They should play fine when you try them again in a few minutes though.

I sent you the log file (I hope you mean the transcoding one, because the other one is more than 500MB big)!
I take a look at the file, and the fps rate is higher than 25 (in fact the transcoding take 15 minutes, but video length was ~25)!
But I cannot see my video playing on the machine that asks for it: after 15 minutes, I had only an error (file not present, or something so)!
I have to say another thing: the computers I need to send the transcoded videos are XP based, so WMP11 doesn't support UPnP, AFAIK! Then I use a plugin, called On2Share, to see Mezzmo in WMP 11 Library!
Now, on server side, the transcoding goes smoothly, but the streaming doesn't start, neither at the end of transcoding process! But, there is the same problem if I set transconding for my Vista based PC (here WMP11 supports UPnP): I obtain the error message "file not found" (on this computer the error is immediate, and transcoding server side doesn't start)! If I deactivate transcoding, the video is played (although there is a "little" lag at the start, but this is not a problem, because it look like it plays smoothly after this time)!

About my network, I use a 100 Mbps wired connection: I don't think that is a problem, because some 1080p videos play smoothly if I view them by traditional Windows folders sharing!


Regarding GPU support - Mezzmo uses ffmpeg for transcoding and since we use it as a separate, external process, you can substitute your own build of ffmpeg (with more format support, better optimized for your hardware, etc...) at any time. Please let me know if you need help building ffmpeg and I can give you some starting directions.

Well, I think I'm still not good enough with C/C++, but if you give me some adivices, I could try!

Paul
01-19-2010, 08:31 AM
Thanks for the logs, we'll investigate and reply via e-mail.

You don't need to know any development languages to compile ffmpeg, but there's a bit of work involved, so I wouldn't recommend doing so without a very good reason ;) A couple of starting points:

http://ffmpeg.org/faq.html
http://ffmpeg.arrozcru.org/wiki/index.php?title=Main_Page