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Xris
10-24-2010, 11:56 PM
Hi,

I'evaluating Mezzmo as a transcoding DLNA server in ordre To broadcaster content To a PS3 connected through wifi.
I don't have more than 10 mbps and thus would like any content beyound this threshold To be systematically transcoded.
I selected 11mbps wifi for the PS3 profile but it does not transcode my HD files (25 mbps). Thus it is not watchable (freezes everything 3 sec).
So, how can I force the transcoding at 10 mbps ?

Thanks,
Xris

Paul
10-25-2010, 07:55 AM
Hi,

Most probably the speed of transcoding is not enough - when you try to transcode a HD movie to lower bitrates, it takes a lot of time and CPU power (to preserve maximum quality). We can try reducing the quality, but your videos will not look good of course.

This is something that will be addressed when pre-transcoding will be added to Mezzmo, since you could prepare your files in advance.

If you try to play that same file that freezes every 3 seconds a little bit later, does it play more or does it stop at the same spot?

Xris
10-25-2010, 10:37 AM
Hi Dennis, thanks for your answer.

Actually, I don't want to pre-transcode the content, as I have several devices which could read the videos (PS3, DLNA TV and laptop), and I don't want to manage content for each devices. It's why I'm looking for a DLNA + transcoding solution.

The Mezzmo server si currently hosted on a high hand machine (Windows 7 64, Core I7 975, 12 Go RAM) thus live transcoding should not be a problem.

I'm aware of the quality downgrade and accepting it. Ideally, I would like to transcode any HD content (1080p) beyond 10 mpbs to 720p - 10 mpbs.
Any non HD content beyond 10 mbps (it should be pretty rare), it shoud also be transcoded to 10 mbps.
So, the main criteria to activate transcoding is the whole bitrate (audio + video).
From my tests, the problem source is the wifi bandwidth. And unfortunatly, I can't move my hotspot (first floor), and the PS3 is at the ground floor.
Thus, the solution would be to transcode and lower the bitrate when needed. I transcoded an HD video to 720p / 10 mbps, and there are no freezes.
Of course, playing the video a little bit later just delays the freezes.

Is the solution within the devices profiles (.prf), and is there any documentation on how to adapt those profiles ?

Thanks,
Xris

Paul
10-26-2010, 07:37 AM
Yes, I think your best bet would be to modify the device profile specifically for your needs and technical limits - there's no official documentation, but feel free to write to support (at) conceiva (dot) com and I'll walk you through the steps, or, if you wish, we can do it here.