Something unexpected happened which made me realize that I don’t understand how Mezzmo uses device profiles.

Since I first began using Mezzmo, we have used a PlayStation 3 to play files from our server. I have always kept transcoding turned off for all devices (which, up until yesterday, meant only the PS3). My approach is that I don’t want the server trying to do anything more than serve... if a file needs to be re-encoded or re-muxed, I’ll do that on my desktop machine, where I can control exactly what happens.

Yesterday my housemate got a Sony XBR55X900B television. Since it has DLNA capabilities, I thought we might be able to skip the PS3 for playing video.

Well, at first it seemed like it wouldn’t play anything except *.mpg files, even though the specifications say it should be able to handle more *.mp4 files than the PS3, and at least most of the same *.avi files.

Then I noticed that Mezzmo had detected it as a Sony Bravia KDL W. Since I had transcoding turned off, I assumed Mezzmo was just feeding it each file as it was; but on a whim, I tried changing the device in Mezzmo to say that it, also, was a Sony PlayStation 3. It now plays the files it said before it could not play.

So, what is going on?

I’m not surprised that Mezzmo doesn’t have a profile for such a new model; what I don’t understand is, with transcoding turned off, what is it doing with the profile? Is a profile needed to communicate correctly with a device even when there is no transcoding involved?

I have since experienced at least one problem using the Sony PlayStation 3 profile with the XBR55X900B. I tried to play an MP4 file that was 720x540, 4:3 aspect, 29.97 fps. The PlayStation 3 plays it as intended; but if I try to use the XBR55X900B directly, it stretches it to 16:9. It is possible that this is a TV setup problem which has nothing to do with the profile... though I don’t know why the default settings, which we haven’t changed as yet, would be to mangle aspect ratios.

Hmmm... and now I see the Advanced Tab under Device Settings, which I hadn’t noticed before. I’m not sure I understand the Help for it correctly. I’m thinking that since I never transcode, I want the first and last delivery rules to be “Always Deliver” and all the rest to be “Never Deliver”? My objective is that I don’t want Mezzmo to “guess” what the device can play, because I’ll never let it transcode anyway. I just want Mezzmo to serve the file as is, and if the device can’t play it, the device can tell me that; then I’ll tinker with the file.

But then I’m thinking that I must be misunderstanding, because why wouldn’t that be automatic when all transcoding is turned off?