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huvince
01-08-2011, 10:52 AM
I have a problem with the HD video which need the transcoding. If the video is less than HD ready no problem
I think that it is a transcoding problem because if I recode the video in mpeg2 (720P or 1080P) and I use it with Mezzmo without transcoding, the problems are not.

Problem 1 with the HD ready video:

Extension : .mks
Taille : 4 696 233 422 Bytes
LxH : 1280x528 pixel
Durée : 1h48m55s
Format : Matroska file format
Codec video : H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
Codec audio : ATSC A/52 / AC-3
Bit rate : 640000 bits/sec
48000 Hz

If I use the default parameter ", the broadcast video format is 4:3 and not 2:35. Thus the format is not respected. Same if I change the format with the TV, at best, I get a 16:9 format

If I use the parameter : "Always delivery" in "Deliver all possible formats for media file to the device", the broadcast video format is correct 2:35. But the broadcast video stops after ± 1m10sec, the sign "pause" appears on TV without manipulation. And during the playback, the video jerk because my CPU is too small.


Problem 2 wuth the full HD Video:

Extension : .mks
Taille : 7 034 131 912 Bytes
LxH : 1920x816 pixel
Durée : 1h33m44s
Format : Matroska file format
Codec video : H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
Codec audio : DCA (DTS Coherent Acoustics)
Bit rate : 1536000 bits/sec
48000 Hz

If I use the default parameter, For this, I use the default parameter, the broadcast video format is correct 2:35. But the broadcast video stops after ± 1m30sec, the sign "pause" appears on TV without manipulation.

Thanks per advance to your guidance
And sorry for my english

Best regards

Paul
01-10-2011, 09:46 AM
You do need a powerful CPU to transcode such files - what sort of CPU do you have? I suspect you get the pause sign because there's not enough data to send to the TV (because transcoding is slower than what's required for smooth playback). One way to check this is if you try to play the same movie again after the pause, does it play further?

huvince
01-16-2011, 08:48 AM
My CPU is a dual core 1.6 Ghz

Precision:

With "Deliver all possible formats for media file to the device",
I thinks too that my CPU is too light because if the source is 720P or more ==> CPU usage 100%
If the video is less than 720P ==> no probl with a CPU usage ± 60%

With transcoding without "deliver all possible formats...", all sources and codec is ok and the CPU usage is less than 40% but just the format is not respected. Same with the option "Always delivery" in "Deliver media files that are prefered by the device"

Question/reflection:

Why the format is not respected if "Deliver all possible formats for media file to the device" is not activated.

My reflection is that the option "Deliver all possible formats for media file to the device" sends the best format for my TV and thus why the option "Deliver media files that are prefered by the device" don't sends the good format?

Suggestion for development Mezzmo:

Add a new functionnality: enable the possibility for the user to test all formats. And after permit to the user to oblige Mezzmo to sent one or more formats selected to the device.

Paul
01-17-2011, 10:13 AM
Yes, a dual-core 1.6 Ghz is not enough to transcode high-def video for real-time playback. You'd need at least a quad-core for this purpose.

I'd recommend to change the Advanced settings back to their defaults - these are there only for specific technical purposes and are not meant to be changed for everyday media delivery. When Mezzmo delivers all possible formats to the device, it's up to the device to pick one, so it's possible that it's not picking what you are expecting. When you have the defaults, Mezzmo will send the best format to your TV (based on the device profile).

We will have pre-transcoding soon, so you'll be able to prepare your files before you stream them. That will help get those high-def files playing.

Thank you for the suggestion - this can be done manually even now, by editing the device profile file directly. We'll consider adding this via GUI as well.

huvince
01-19-2011, 08:31 AM
Thanks for your help,

Yes, a dual-core 1.6 Ghz is not enough to transcode high-def video for real-time playback. You'd need at least a quad-core for this purpose
What is the quad core minimum?


Thank you for the suggestion - this can be done manually even now, by editing the device profile file directly. We'll consider adding this via GUI as well.
With this remark, I test an other "Device profile". I took an profile approximate compared to my device
My device is a "Sony Bravia KDL" serie "V5500" and I chose the "Sony Bravia KDL W".
Apparently this selection works.
I test more.

Paul
01-19-2011, 08:34 AM
See the requirements at the bottom of this page: http://www.conceiva.com/products/mezzmo/default.asp

Basically, you'd want at least 2 cores, so that one transcodes and one sends data to the device. If a file is 720p or higher, it will require multiple cores transcoding at the same time to be fast enough for real-time playback, so you'll need a quad-core (3 cores will transcode and 1 will send data). Or an i7, where you have 4 cores, but 8 threads, so 7 threads can transcode and 1 will send.