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FlyingVguitarist
04-25-2011, 09:20 AM
Hello,

I am evaluating Mezzmo as my DLNA server solution and am close to purchasing it. I've spent many hours reading forum posts and trying different file types. Like others, my server shoots up to 100% the moment I start a movie (FFMPEG.exe). I have a general idea what is happening, but need a solution to eliminate the need to transcode.

First, let me give you the lay of the land

My network is wired gigabit.
The server is a single core P4 3.4 GHz (Prescott) with 4 GB RAM.
I have a DLink NAS hosting a few test files. I tried storing them on the server, but there is no performance difference. Therefore, the NAS will ultimately store my video files.
My TV is a Samsung 60" LED (series 6), model UN60C6300SFXZA.


Testing Results

My testing source is a standard definition ISO image created by AnyDVD-HD.
Using different rendering applications, I created 4 files:


AVI file rendered at 720x404 using MPEG-4 part 2 video codec, ATSC A/52 / AC-3 audio codec, 1.5 Mbps data rate.
AVI file rendered at 720x404 using MPEG-4 part 2 video codec, ATSC A/52 / AC-3 audio codec, 8 Mbps data rate.
AVI file rendered at 720x408 using H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 video codec, AAC audio codec, 1 Mbps.
MKV file rendered at 720x408 using MPEG-2 video codec, ATSC A/52 / AC-3 audio codec, 8 Mbps.
I also snagged a VOB file from the ISO image.


VOB file plays within 20 seconds. Server CPU utilization at 3%. No transcoding.
AVI and MKV cause 90%-100% CPU utilization (FFMPEG.exe).
Mezzmo transcodes AVI and MKV files.
I played the MKV file twice. The first time, Mezzmo created the following file: 3-mpeg_ntsc-mpeg2video-ac3.mzt. The second time I played the same MKV file, it loaded fairly quickly and displayed the correct movie length. However, Mezzmo created a second file (PAL): 2-mpeg_pal-mpeg2video-ac3.mzt.


Questions

What is the native file format for my TV?
How can I avoid transcoding? May I assume the answer is to render in the native file format?
Why does a VOB file play with minimal CPU utilization and doesn't transcode?
Can I render files at 1920x1080 and expect them to stream properly (assuming no transcoding).
Why did Mezzmo transcode the same file twice -- one as NTSC and the other as PAL?
What is the preferred rendering application?


Thanks in advance to all who answer.

FlyingVguitarist
04-26-2011, 08:30 AM
Hello,

I see 40 users viewed my post and I have no feedback. Perhaps I provided too much detail. Can someone tell me the native file format for a Samsung series 6 TV so Mezzmo doesn't transcode?

Thanks much!

mark11
04-26-2011, 02:22 PM
*gulp*

Mezzmo seems to be doing an awful lot of transcoding. Have to checked make sure you are using the correct profile? Maybe a different profile? Maybe turn transcoding off all together?

Both of my Samsung devices (while not your TV) play almost everything without tanscoding. If you do not truly need to transcode, then I am sure someone would jump in and help you update the profile. Maybe even more than 1 out of 40 people would help (but who's counting).

mavrik64
04-26-2011, 11:39 PM
Hi,

http://www.samsung.com/us/support/downloads/UN60C6300SFXZA and pull down the user manual (not the quick guide). Page 34 will tell you what you need to know about native play file types etc. The guys from Mezzmo will probably get back to you when they are back in work (i assume today some time). Like mark11, my Sammy will also play most files natively too.

Paul
04-27-2011, 10:17 AM
What is the native file format for my TV?

Samsung C-series TVs support quite a few video, audio and image formats natively. Your manual should list the full list for you. You seem to be interested in video, so a quick supported list is MPEG-2, MPEG-TS, AVI, MKV, MPEG-4 and ASF. If you are reasonably technical, you can look at Mezzmo's device profile for your TV model and that will describe what Mezzmo delivers natively and what it transcodes. Your TV seems to be a Samsung C-series TV (make sure you have Samsung C selected as the device profile in the Media Devices dialog). That is the SamsungLA.prf device profile and you can find it on your computer using this FAQ: http://forum.conceiva.com/showthread.php/467-FAQ-Where-are-device-profiles-located. View it with a text editor like Notepad.



How can I avoid transcoding? May I assume the answer is to render in the native file format?

The only way to avoid Mezzmo transcoding files is to have files that your DLNA device can play natively.



Why does a VOB file play with minimal CPU utilization and doesn't transcode?

A VOB is an MPEG container and your TV plays it natively, so Mezzmo streams it without transcoding.



Can I render files at 1920x1080 and expect them to stream properly (assuming no transcoding).

Yes.



Why did Mezzmo transcode the same file twice -- one as NTSC and the other as PAL?

Mezzmo does not transcode the same file twice. It probably tried to start playing the next file in your playlist.



What is the preferred rendering application?

Sorry, I do not have any recommendations for you. Perhaps some Mezzmo users can recommend their favorites?

Note 1: Once a file has been fully transcoded by Mezzmo, it is kept on your computer and the next time you try to play the file, the transcoded file is delivered immediately without any transcoding. See Transcoding Settings dialog in Mezzmo for more details.

Note 2: The next major version of Mezzmo will have a "pre-transcode" feature whereby you can prepare your files for a device beforehand so that they are ready to be played immediately without any "on-the-fly" transcoding. This will help users who have lesser powered computers (single core, dual core, etc.) that cannot adequately transcode HD video "on-the-fly" in real time.

FlyingVguitarist
04-27-2011, 12:02 PM
Great information. Thanks. I saw the support codec list in my manual, but am not sure what program to use to render the video. Is it better to render from an ISO or decoded VOB files?

I will look at the Samsung profile and make changes as needed. I want to avoid transcoding at all cost; transcoding doubles HDD space consumption.

Thanks much. Will likely be back with more questions.

FlyingVguitarist
04-29-2011, 10:09 AM
I gave my TV a static IP address, set the profile to Samsung C and dechecked transcode incompatible media files. All five test files play...server CPU at 0%-1%.

Thank you all for your feedback. I still have a little hair left :)

BTW: is there a cheap DNLA decoder I can purchase for my Samsung series 4 TVs? They don't support DNLA, but have HDMI inputs.

Paul
04-29-2011, 10:14 AM
Glad to hear you are up and running now. For a cheap DLNA media player, I'd suggest a WD TV Live. They have good format support. Mezzmo works well with them. And, they are typically under $100.

FlyingVguitarist
04-29-2011, 11:22 PM
Before I begin archiving my movies, I'd like to settle on a format. It seems to be a balance of file size, data rate, control (play/stop/etc.) and encoder(s).

Of all test files, this one looked/performed the best:

MKV file rendered at 720x408 using MPEG-2 video codec, ATSC A/52 / AC-3 audio codec, 8 Mbps.

What is the best rendering configuration to use? I know some of this is subjective, but any opinion is appreciated.

Paul
05-02-2011, 10:02 AM
What is the best rendering configuration to use? I know some of this is subjective, but any opinion is appreciated.
Do you mean a video conversion application? Sorry, I'm not sure what you mean by "rendering configuration"... Or is it a video/audio format combination?

Have you tried converting your files to MKV with h264 video and AC3 sound? I would think that would give you better results than MPEG2.

FlyingVguitarist
05-02-2011, 11:04 AM
Dennis,

You inferred my question accurately. It is overwhelming learning a new concept (DLNA), testing numerous rendering combinations and having to choose a long-term standard.

Yesterday I began rendering movies as MKV, H.264, AC-3 passthru, DTS passthru. Takes a while to render (using a quad core computer), but the video quality looks good and my amp detects both audio streams if present.

Question: is there a way, without creating 26 playlists, to locate movies by first character? Movie lists can get fairly long and scrolling is not an sustainable as the library grows. I already broke up my movies into a few playlists, but I can forsee challenges in the future.

Paul
05-02-2011, 11:06 AM
Some devices allow you to search through the playlists, but it's really up to the device. If it doesn't have that functionality, then the only option is to create the 26 playlists (plus something that will accommodate files that do not begin with a letter).