Topic 'Re: Optimum App for Laptop: SD-only?' in forum 'OptimumOnline' - dslreports.com

Re: Optimum App for Laptop: Bit-Rates?

Thu, 27 Sep 2012 13:59:10 EDT

rtbond posted : I believe I found the ABR manifest XML file that is sent from the network to the ABR client in the capture. The manifest indicates there are four ABR streams made available for laptop streaming. I have listed these below (these are the MP4 video streams, audio is a 96 kbps stream that would added to the numbers below)

There may be a different set of streams for the iPhone/iPads, as these applications are not MS Smooth Streaming (Silverlight) based but rather Apple HLS.

ABR Streams for Optimum App for the Laptop

Bit Rate: 0.857 Mbps [~ 1.0 Mbps with audio]
Frame Width: 480
Frame Height: 270

Bit Rate: 1.445 Mbps [~ 1.5 Mbps with audio]
Frame Width: 640
Frame Height: 360

Bit Rate: 2.0325 Mbps [~ 2.1 Mbps with audio]
Frame Width: 960
Frame Height: 540

Bit Rate: 2.913 Mbps [~ 3.0 Mbps with audio]
Frame Width: 1280
Frame Height: 720

Re: Optimum App for Laptop: Bit-Rates?

Thu, 27 Sep 2012 11:51:25 EDT

rtbond posted : Looking at the capture I see a series of HTTP "Get" commands, which I believe is the ABR algorithm requesting progressive higher bit rates when I first tune the channel (in this example Yes-HD).

So the Get data looks something like:

.../ yeshd.isml/QualityLevels(857000)/Fragments(video= ...

I am guessing the "857000" is the initial video stream bit-rate of 857 kbps.

The series of Get requests have progressively increasing quality levels (OK, with a dip in the middle)

857,000 => 2,913,000 =>1,445,000=>2,913,000

There are also a series of Gets for the Audio stream, settling at 96 kbps.

So the combined audio/video rate looks to be about 3 Mbps (if I am interpreting the QualityLevels parameter correctly).

There may be a series of other video bit rates below 2,913,000 bps, but the ABR algorithm requests the ones it thinks are likely to be the best (hence the reason it jumped from 857 kbps to 2.9 Mbps, then back down to 1.4 Mbps, and finally back to 2.9 Mbps. Also if I look at the total bit rate of the capture (with no other significant network activity other than the Optimum App) I see a bit-rate around 3 Mbps.

From what I have read the ABR client requests a "Manifest" from the ABR server that includes a list of the bit-rates available, so the laptop application knows what bit-rates are available.

Re: Optimum App for Laptop: Bit-Rates?

Thu, 27 Sep 2012 10:39:04 EDT

IllIlIlllIll posted : i would like to know what XML setting the SL player used for that bandwidth, i havent had time to "play" with this to find out though (full time job consumes time).
the debug mode for the SL player should indicate it though.
--
Suffolk County NY Police Feed - »www.scpdny.com
PS3 Gaming Feed - »www.livestream.com/elitedata

Re: Optimum App for Laptop: Bit-Rates?

Thu, 27 Sep 2012 09:46:01 EDT

rtbond posted : I did a quick test of the bit-rate when watching live TV on a laptop (wired Ethernet). I found sports HD channels in the neighborhood of 3 Mbps and non-sports HD channels closer to 2 Mbps. I did this early in the morning so network congestion should not have been a factor.

I used WireShark to make the measurements.

Can anyone confirm these numbers?

--Rob

Re: Optimum App for Laptop: SD-only?

Fri, 14 Sep 2012 11:57:46 EDT

rtbond posted : Cool, I look forward to your findings

Re: Optimum App for Laptop: SD-only?

Fri, 14 Sep 2012 11:36:58 EDT

IllIlIlllIll posted : i will do a test @ 1280x720 and measure the actual throughput downstream being used.

Re: Optimum App for Laptop: SD-only?

Fri, 14 Sep 2012 11:15:00 EDT

rtbond posted : Those bit rate numbers (e.g., 22 Mbps) are not taking into account the video compression gains of H.264. I am sure the Optimum App streams are H.264 based. A well implemented H.264 stream of HD content should be 5 Mbps or less (i.e., at least half the bit rate of the equivalent quality MPEG-2 encoded stream).

With adaptive bit rate streaming a given program stream is encoded at multiple bit rates (resulting in various video qualities) and the network dynamically determines what bit rate the client (i.e., your laptop, iPad, etc) can best handle given the performance of the network (a function of the speed of your subscription, network congestion, and client responsiveness).

With this approach you will often see the video quality improve shortly after the streaming begins, as the algorithm gradually tries higher bit rates until it reaches an optimal rate (given the network conditions)

Re: Optimum App for Laptop: SD-only?

Fri, 14 Sep 2012 09:52:07 EDT

IllIlIlllIll posted : here are the specifications measured in bytes.
use the bit calculator to see measurement conversions.
»www.matisse.net/bitcalc/
audio: AACL, 96000b, 2 channel, 48Khz, 16Bit
video: AVC1:
320x180 @ 417000b
416x240 @ 857000b
480x270 @ 857000b
640x360 @ 1445000b
960x540 @ 2032000b
1280x720 @ 2913000b
its interesting to note that the highest resolution 1280x720 uses 22.22Mbit downstream bandwidth.
without "Boost", i doubt this would work reliably, it would "adaptively" reduce to the next step down to 960x540 (15.5Mbit) unless the modem downstream cap (without Boost) is "ignored" within the "walled garden".

--
Suffolk County NY Police Feed - »www.scpdny.com
PS3 Gaming Feed - »www.livestream.com/elitedata

Re: Optimum App for Laptop: SD-only?

Fri, 14 Sep 2012 08:22:27 EDT

limegrass69 posted : Have you tried logging out and in to the app?
Have you tried uninstalling and reinstalling the app?
Maybe that could straighten out your box issue.

Re: Optimum App for Laptop: SD-only?

Fri, 14 Sep 2012 06:20:14 EDT

rtbond posted : I heard from a Cablevision source on another forum that the video is encoded 720p (with adaptive bit rate streaming). It must be the adaptive bit rate streaming that made the bit rate appear below 720p on my Windows 7 laptop.

Actually looking at the streaming video this morning it looks HD. Maybe I need new glasses!

The bogus STB listing is puzzling, but not worth my time at the moment. I have not tried using the remote control/STB tuning feature of the App, nor another laptop. As I said, the picture quality looks good this morning, so perhaps when I was first playing with the App there was network congestion and I got stuck with one of the low bit rate streams.

Thanks!

-Rob

Re: Optimum App for Laptop: SD-only?

Fri, 14 Sep 2012 00:23:04 EDT

frdrizzt posted : Maybe I'm confused, but since the app doesn't stream through the box at all, why would the HD/SD type of box in your home affect what streams to the PC? Also, the selected box in the top corner of the PC/MAC app is used for remote control/tune to channel feature on the box only. I have mixed HD & SD boxes at home, and the resolution (and channel names) are no different when I select the HD box as the box or the SD box in our guest room. I have tuned off the channel & tuned back in in case that had any impact, and there was zero.

Basically, my question is "has anyone been able to force the SD stream of an HD-capable channel on the PC/MAC app? I could check my mother's SD-only house to find out definitively, but I can't imagine she would not get HD on the laptop.

My suggestion would be to reinstall the app & silverlight, and see if there is any change. Next I'd try a different device, if possible. Either use another laptop to test, or take yours somewhere that does not have the problem and try it there. Lastly, contact support to have them refresh your account & ID to see if there is improvement.

Re: Optimum App for Laptop: SD-only?

Thu, 13 Sep 2012 22:50:59 EDT

Tursiops_G posted :

said by rtbond:

I also noticed in the Home portion of the App (upper left corner) it lists STBs. In my case it list seven STBs (four HD and three SD). In reality I have 5 STBs, all HD. I am not sure where the STB info being shown in the App is coming from (we never had any SD STBs)

Sounds like some kind of glitch... :huh:
The Optimum App for Laptop gives you the option to select any of the registered STBs on your account to be used to stream the programming to your Cable Modem/WiFi...

Change the selected STB to point to one of your correct HD boxes, and it *Should* then stream HD content when available.

As for the 'bogus' STB entries, I have no idea on what to do, other than to contact CV Customer Support about it... :hmm:

HTH,

-Tursiops_G.
--
If You're Unsure, "RTFM"... If You're SURE, "RTFM" Anyway. ;)

Re: Optimum App for Laptop: SD-only?

Thu, 13 Sep 2012 18:14:30 EDT

anon posted : The app for laptop works as it does on TV for me...for example, if I tune to channel 2, then I see CBS-HD without going to 702 because I have two HD boxes.

Re: Optimum App for Laptop: SD-only?

Thu, 13 Sep 2012 06:31:13 EDT

rtbond posted : So when you tune an HD channel in the Optimum App for the laptop Guide does it not auto re-tune to the SD version?

That is the behavior I see.

I also noticed in the Home portion of the App (upper left corner) it lists STBs. In my case it list seven STBs (four HD and three SD). In reality I have 5 STBs, all HD. I am not sure where the STB info being shown in the App is coming from (we never had any SD STBs)

Re: Optimum App for Laptop: SD-only?

Wed, 12 Sep 2012 18:14:03 EDT

anon posted : I have the Optimum App for laptop, and I receive HD quality channels, as long as they are available on my TV package.

Optimum App for Laptop: SD-only?

Wed, 12 Sep 2012 07:43:25 EDT

rtbond posted : I was just playing a bit with the Optimum App for the Laptop. It seems to work pretty well and I like the program guide. It appears, however, that all programming is delivered as SD. Can anyone confirm this?

If I tune an HD channel from the guide it seems the SD version is always streamed (so for instance if I select YES-HD (715) I receive channel 70 (YES-SD)).

Even as SD-only, it seems fine for viewing on a portable device.

--Rob