MCU 8510 Content Sharing Blurry

LordBoBCUP · ‎09-21-2016

Hi,

We are currently facing an issue where content is delivered extremely blurry. We are presenting from codecs (C40, SX20) and receiving on a range of codecs (C40, SX10, SX20) & Jabber it doesn't seem to matter what we receive it on.

I have tried different scenarios (forcing the settings on a per call basis) where I use Transcoded, Hybrid & Passthrough. Passthrough seems the clearest but not by much. We are running the latest MCU firmware (4.5) and the codecs are all running 7.x of the TC firmware either 7.5.3, 7.2.1 etc. Neither combination appears to make a difference. Content isn't used that frequently so this may have been occurring for quite some time now without being noticed or mentioned.

Can anyone suggest settings that I may have missed or something. Has anyone seen this before. I would expect a fairly static 720p image would be crystal clear (powerpoint, excel etc that doesn't change much).

Thanks

Alex

Patrick Sparkman · ‎09-21-2016

What is the input quality set to on the endpoint that is being used for content?

it sounds as if it might be on "Motion", which means the inout will favor motion over resolution. The default setting is "Sharpness", which means it will favor resolution over motion.

What does the content channel status show on the MCU when showing content, also what is the call rate being used?

Because the main video and content channels share the overall call bandwidth, if the call rate is too low, the content channel won't have enough bandwidth for 720p video.

LordBoBCUP · ‎09-21-2016

Hi Patrick,

I just checked the last unit I tested on and you are correct the input is in fact set to Motion over sharpness. I've adjusted it to Sharpness it seems like it might be marginally clearer, but nothing substantial.

Call rate is 1920kbps, MCU shows the video channel at 1920kbps, Its showing a rate of 1.86Mbit/s 1280x720 resolution using H.263+. I noticed on the transmit side, its showing transmit rate of 896kbps with the bit rate imposed by endpoint message. Not sure which endpoint and/or why. The endpoints are C40 (Presenting), SX80, MX300 & 1x Polycom HDX8000.

Do you know what the requirements are for 720p video & content on the same overwall bandwidth, is 1920kbps too low?

Patrick Sparkman · ‎09-21-2016

You're obviously getting 720p with 1920kbps call rate, and should be fine. Something else to take a look at is the OptimalDefinition Profiles on the endpoint. Take a look at the SX20 TC7.3 Admin Guide on pg 112. I would recommend setting the MCU content channel to Hybrid mode, so capable endpoints can take advantage of passthrough content, while the MCU can still offer transcoded content for endpoints that might need it.