Getting 720P

[kekfoong]

Hi all,

i would like to know if

-i would like to get 720P, i need to dial at least 1.5mb or above?

-i am dialing multi-sites (e.g 3 sites), there is no way i can get 448P or 720P no matter how high i call?

[DRI]

What type of EPs and what are the sw versions of the EPs that are in the call??

[kekfoong]

I think only HD Epts can achieve 720P. So let's take codec 6000 MXP w/ HD cam and full features.

For software version is F6.2

[Sean Lessman]

I think only HD Epts can achieve 720P. So let's take codec 6000 MXP w/ HD cam and full features.

For software version is F6.2

With the TANDBERG 6000 you can do 720p in a point to point call or with a 720p capable MCU. If you leave the codec set to 'motion' you will get 720p at speeds of 1.5Mbps or higher. If you set the codec to 'sharpness' you will get 720p at speeds of 1Mbps or higher.

Sean

[kekfoong]

Thanks Sean,

Noted, thank for you info.

Most of my questions were all answered by you, you are indeed a Super Guru!!!!

[przemekw]

With the TANDBERG 6000 you can do 720p in a point to point call or with a 720p capable MCU. If you leave the codec set to 'motion' you will get 720p at speeds of 1.5Mbps or higher. If you set the codec to 'sharpness' you will get 720p at speeds of 1Mbps or higher.

Sean

What about FPS at the speeds?

How much of bandwidth will take content on H.239?

Regards,

Przemek

[Glen Sykes]

The FPS is determined by the amount of motion on the screen, in addition to Bandwidth, Resolution and all the other considerations. Your question is actually quite ambiguous, you need to be more specific about the conditions of the call.

This has been discussed at great length already in many previous threads.

The amount of bandwidth used in the H.239 session may be determined in the system configuration and is expressed as a percentage of the overall call bandwidth.

[przemekw]

The FPS is determined by the amount of motion on the screen, in addition to Bandwidth, Resolution and all the other considerations.

I would like to provide video call with full motion :) - I don't want to be frozen. During conversation is needed to show something, move hands etc. That's why I prefer VC not tele conference with phone. So I need "full" motion on screen.
If I have 1Mbit, full motion is needed, how many FPS I get on Tandberg and Polycom EP at 720p ?

Regards,

Przemek

[Glen Sykes]

At 1Mb, with 720p resolution, with both Tandberg or Polycom, you will get perfectly acceptable motion handling for most face to face VC meetings. The frame rate visible on screen will be 30fps.

The frame rate starts to drop once you start to introduce 'full' screen motion i.e. when 100% of the image on screen is changing (for example when a camera is panning). Under these conditions, the performance of the Polycom and Tandberg start to exhibit different performance characteristics, with typically the Polycom system showing better performance. However, this is not clear cut. At 1Mbps, no codec that I know of will give full 30fps with 100% screen refresh rate, because 1Mbps is not enough bandwidth. Consider HDTV, the bandwidths used to transmit 720p images at 30fps are way in excess of 1Mbps to ensure the frame rate remains of acceptable quality, especially during sports broadcasts etc.

So, please understand, you can't just talk about fps in isolation, you've given some constants in your question, such as 1Mbps, 720p, (and I'm assuming H.264 anyway), but you also need to consider what proportion of the image on screen is changing from one frame to the next.

If your considering sending HD-DVD across your video call using 720p, then chances are you'll get better performance from the Polycom, but I think you'll need more than 1Mbps to get a good quality image. Now this is where is gets interesting, because Tandberg have w448p, which is a native 16:9 resolution and performs very well at 1Mbps for motion handling. Polycom have yet to implement a 16:9 format resolution that is lower than 720p resolution to provide good motion handling at lower bandwidths.

However, if you're primarily using the system for video meetings, I think you'd be satisfied with either. The best recommendation I can give you is seek out a demo from a good reseller who can show you both and don't be afraid to ask questions.

Hope this helps,

Glen

[przemekw]

At 1Mb, with 720p resolution, with both Tandberg or Polycom, you will get perfectly acceptable motion handling for most face to face VC meetings. The frame rate visible on screen will be 30fps.

I saw some info regarding Tandberg that does not have enought cpu power - send only 35k macroblocs, not 108k (720p, 30 fps).

Is it correct?

Przemek

[Glen Sykes]

At 1Mbps?

There is a lot of FUD about this floating about, and I've seen the same report (Wainhouse?) that discusses the static macroblock capability of the Tandberg codec amongst others. Have you seen the Tandberg response, or the subsequent Wainhouse response?

As a reseller, I'm in no position to confirm or deny the statement, and neither can I say that I have measured this myself, all I have to go on is what has been written, and what I have personally observed.

However, as I've written the chances are you will get better performance from the Polycom HDX than the Tandberg MXP when sending full motion (i.e. 108k macroblocks), providing your call has sufficient bandwidth (I don't think 1Mbps is enough).

The question you have to ask yourself though, is what is the likelihood that your call scenario will require 720p resolution, when sending full screen motion (i.e. a Blu-Ray DVD or a sports broadcast). If the likelihood is high, then yes consider something like the HDX, however the MXP is perfectly suitable for most videoconferencing applications, as I've described above.

I doubt you'll get a definitive answer on a public forum as to the specific compute capability of the Tandberg MXP codec, or any other make of codec for that matter.