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HH55
09-02-2012, 10:34 AM
I assume the device bitrate setting (less quality to best quality) determines the bitrate the the video is sent from the server to the device. However, I've had trouble seeing any difference when playing with the values. I also assume that this same setting will determine the bitrate of a pre-transcoded file. Again, I've had trouble seeing the difference. I have a Sony BDP-S590 and it can display the bitrate as it is playing a video, and I haven't seen it change after changing the device bitrate setting on the server. Am I doing something wrong? Am I wrong in assuming that my payer will show a different bitrate based on the setting on the server? Also, is there a way to configure it to pre-Transcode only video's whose bitrates are natively over a certain threshold?

Thanks.

Paul
09-03-2012, 10:47 AM
Hi HH55,

Please send us a set of logs and we'll look at the bitrate settings being used during transcoding. Turn on logging (http://forum.conceiva.com/showthread.php/419-FAQ-How-to-turn-on-diagnostic-logging). Set the device's bitrate setting in the Media Devices dialog to what you desire and then pre-transcode a video file for this device in Mezzmo. Next, start your Mezzmo server and stream the video file to your Sony BDP. After it starts playing, stop your Mezzmo server and exit Mezzmo. Zip up all the logs and send them to us at support [at] conceiva [dot] com.

HH55
09-04-2012, 09:11 AM
My latest testing shows that the pre-transcoded files definitely have a lower bitrate than the non pre-transcoded, although I'm still not sure if it makes a difference if I set the bitrate setting all the way to the left or to the right (they both have fairly low bitrates and I don't see a visual difference). My main question now is whether I should be seeing the same actual bitrate if it is using the pre-trasncoded file vs. the original. I thought the only difference is that without the pre-transcoded file, it transcodes on the fly and with the pre-transcoded file, it doesn't transcode on the fly. Which tells me, it should be the same bitrate either way. However, I'm seeing about 1Mbps with the pre-transcoded file and about 9Mbps with "on the fly" transcoding. It looks like as long as the original file format is acceptable by the player, then it doesn't transcode on the fly, it just streams the original. Can you confirm? If this is the case, then how does the bitrate slider affect streaming the original file? My preference is to not pre-transcode my whole library but rather just set the bitrate lower so it doesn't have issues. if you'd like, I can turn on logging, then play a file with the bitrate slider to the right, then to the left, then I can play a pre-transcoded with bitrate to the right and then pre-transcoded with bitrate to the left. Let me know.

Paul
09-04-2012, 09:53 AM
Using the default settings in Mezzmo, if the original file is supported by the device (i.e. can be played by the device), then the bitrate slider will not be used. Mezzmo server will stream the original file directly to your device. The bitrate slider is used when files are transcoded.


...if you'd like, I can turn on logging, then play a file with the bitrate slider to the right, then to the left, then I can play a pre-transcoded with bitrate to the right and then pre-transcoded with bitrate to the left. Let me know.

Yes, please. Send the logs to us at support [at] conceiva [dot] com.

Hayden
09-04-2012, 08:26 PM
Just a quick question about this issue. What bit rate slider are we talking about and where is it?

HH55
09-05-2012, 07:09 AM
The bitrate slider that I'm talking about is the quality control slider under the device settings --> performance (I think).

Paul - So, you're saying that if the original file is supported by the player then it just streams it without modification. But, I thought one of the benefits of using Mezzmo is to enable it to adjust the streaming to the quality of the network connection. So, if I have a slow wireless connection, it would adjust the bitrate (or some other quality variable) to still make the file playable. From what you are saying, the only way to solve issues like that is to pre-transcode the file. Is this correct?

I can still send a log of the two different transcoded files (one with the slider to the left and the other with the slider to the right). I just may not be able to do it tonight. Thanks for your help.

Paul
09-05-2012, 09:49 AM
Hi HH55,

You are right - if the file has a too-high bitrate for your home network and it is supported by your device, then you could pre-transcode the file and it may lower the bitrate to make it more acceptable. Perhaps a better alternative is we can create a device profile for you that lowers the maximum acceptable bitrates for formats supported by your device and any native file that has higher bitrates will be forced to be transcoded (and then the bitrate slider will come into play). If you would like this device profile, please contact us at support [at] conceiva [dot] com. In your email, let us know the device profile you are currently using and the FFmpeg information on one of the high-bitrate files that is stuttering due to your wireless bandwidth. To do this, right-click on the file in Mezzmo and then click 'Get FFmpeg Information'.

Hayden
09-05-2012, 04:59 PM
Duh Oh! I thank you for the tip. Never looked in that area. Many thanks!!




The bitrate slider that I'm talking about is the quality control slider under the device settings --> performance (I think).

Paul - So, you're saying that if the original file is supported by the player then it just streams it without modification. But, I thought one of the benefits of using Mezzmo is to enable it to adjust the streaming to the quality of the network connection. So, if I have a slow wireless connection, it would adjust the bitrate (or some other quality variable) to still make the file playable. From what you are saying, the only way to solve issues like that is to pre-transcode the file. Is this correct?

I can still send a log of the two different transcoded files (one with the slider to the left and the other with the slider to the right). I just may not be able to do it tonight. Thanks for your help.

HH55
09-06-2012, 08:17 AM
Paul,

I turned on logging and streamed three different versions of the same file. First, the original, then I set my device settings to Best Quality and pre-transcoded the file, then I deleted the pre-transcoded file and set my device settings to Less Quality and pre-transcoded the file. Sending the logfile to support@conceiva.com.

As far as creating a profile for me, that would be great. Maybe one that would max out at 4Mbps another that would max out at 2Mbps. That way I can try out each one. Seems like a lot of work for you, when if you were to provide some tuneable parameters within the application, I could do this on my own.

Paul
09-06-2012, 09:06 AM
Thanks - we'll analyze the logs and get back to you shortly.

HH55
09-22-2012, 05:55 AM
It's been over two weeks - any luck?

Paul
09-24-2012, 08:51 AM
Sorry HH55 - we misplaced your email. I just found it and we'll get back to you ASAP.

Paul
09-24-2012, 12:33 PM
Hi HH55,

We did just find a problem with the Video bitrate slider and have fixed it. This fix will produce different results in your tests. This fix will be included in upcoming release due out in the next few days.

Here's an explanation how the Video bitrate slider works in Mezzmo:


You set the type of network connection that you are streaming to your DLNA device on the Device Settings dialog (General page) for your device. For example, if you are streaming using wireless N to your DLNA device from your computer, then set the Connection field on the Device Settings dialog (General page) to 'Wireless N'. This setting is important when transcoding, so it is recommended to choose the right type of network connection that you have.
Mezzmo will limit the maximum video bitrate when transcoding videos to the (real-world) bandwidth limit of the connection type that you have chosen. This applies to both transcoding on-the-fly and pre-transcoding. The video bitrate of the transcoded videos will not exceed the (real-world) bandwidth of your home network & this should produce stutter-free streaming.
The Video bitrate slider on the Device Settings dialog (Performance page) provides additional video bitrate control, whereby it can be used to reduce the maximum video bitrate further - particularly in the case that your home network connection is not performing optimally. For example, your wireless connection may not have full signal strength to your computer or DLNA device, or your home network may have congestion problems.
The Video bitrate slider steps by increments of 10% - starting from 10% (on left) to 100% (on right). The default setting is 100%. The percentage value selected is applied to the (real-world) bandwidth limit of the connection type you have chosen. For example, if your home network uses 1Gb Ethernet cables, then you would choose 'Gigabit Ethernet Cable' as the Connection type. However, if you found that your home network's bandwidth was not optimal (due to congestion, etc.) , then you could move the Video bitrate slider to (say) 60%. This means the maximum allowed video bitrate for any transcoded video would be 60% of (real-world) bandwidth limit of a Gigabit Ethernet cable, and this may stream better on your home network.