[Bug] [C-200] Stuttering revelation... smb gige 24p hdmi mysteries...

[digitalman]

This could be long but i will try to be concise...

1st off: my definition of "stuttering" is video hiccups, skips frames, audio cuts out, sometimes receiver may lose audio signal, then get it back with good video for a few seconds then stutters again etc...

I had an A110, hdmi connected to an Onkyo tx-sr806 hdmi connected to a panasonic ae3000u projector. running yamj with nmtserver http streaming it has happily streamed every bluray m2ts file i have thrown at it for years.

Now the A110 was not able to play really high bitrate m2ts files through samba shares, i never figured out the exact cutoff but i imagine it was around 40mbit would cause it to choke and stutter. not an issue as http always worked.

So i bought a C200 and expected it to work "better" i moved my a110 to the family room and connected it to a sony receiver and sanyo z2 projector, it still happily streams from nmtserver every high bitrate file i have sent it.

So now i have the C200 in its old spot with the onkyo and panasonic projector. It has not been able to play all of the higher bitrate m2ts files. obviously there is nothing wrong with my server or network as the a110 was and still is working. again i think the cutoff is somewhere around the upper 30mbit to 40mbit that it has problems.

i also have my c200 connected with component output to the tv in my bedroom and that has worked fine also.

so here goes some interesting tests and observations. a file i was just testing last week with http streaming is baraka m2ts, it played but i think it was hitting right on the threshold, it would get to certain scenes like the waterfalls and stutter. So this week i get the new may firmware installed, play baraka again and it plays through those sections just fine, but i tried playing some higher bitrate concerts, rush r30 and depeche mode and stuttering is still there.

Conclusion- new fw had a minor speed increase.

so i had a thought, i wonder if there is any issue with hdmi streaming to my onkyo? so i turned it off, only played out component rgb to my led tv set. tried just browsing the workgroup samba share to play and viola! rush r30 m2ts concert played fine on my tv. turned my onkyo back on and playback stuttered on both the projector and tv set.

Conclusion- hdmi streaming can cause some stuttering versus component output

so im thinking about this Rush r30 concert being a 29.97 bluray as opposed to my normal 24p movies i watch and my c200 was still set to 24p, so i changed it to 1080p60 played the file and again it played perfectly! now the problem was not simple 3:2 pulldown issues, it was really stuttering and losing audio.

Conclusion- 29.97 to 24p output conversion seems to have a performance issue with the c200 and can cause stuttering.

So today i was reading some of the gigE complaint threads and saw some people post that they were only getting 50mbit file xfer speeds with 100mbit setting on the c200 but the ones that can get gigE to work get 200mbit speeds. that is a revelation for me as my a110 streams fine
at 100mbit setting, so could it simply be that the 100mbit c200 setting is only getting throughput that is too slow for my 50mbit depeche mode concert? So i go into network settings and change it to auto. checked my Dell Powerconnect 2616 GigE switch and it lights up that port at 1000mbit connection. So then i simply browsed my workgroup to the depeche mode 50mbit m2ts bluray file and viola it plays perfect without glitching! even with lame old samba shares.

Conclusion- c200 ethernet 100mbit setting is too slow to play high bitrate 40mbit+ m2ts files. must find a switch that works at 1000mbit with it or your out of luck!

I am once again a happy camper! I hope this info might be helpfull to others. My c200 is finally working as it hoped it would when i bought it.

[accident]

Thanks for defining what you call stutter. For a learning moment, stutter is pretty much the same as an online video stopping to buffer and then starting again. It can be subsecond. Some gear may not react to this well so audio dropouts can happen depending on your setup on a whole..

The pch is more than able to handle max bitrates of existing blurays over the network. 100mbit is greater than 65mbit last I checked. There's a few factors that can impact this but it's another one of those setups on a whole. I actually like to use a usb thumbdrive on my driveless players to do a copy from nas to pch (using the pch interface for the copy).. that'll give you a general idea about how all the pieces are working together for a throughput standpoint. It really needs to be that pull copy to test because pushing a copy to the pch using the pc as the starting point is not an accurate measurement of how it's performing when the pch initiates the connection like it would for playing something. There is a rather common issue I run into with networking gigs where you'll see a copy go faster in 1 direction.


Part of your "findings" is actually why so many people want the auto-resolution option. It would allow the pch to not scale the video and optimally output it so people can use the scalars in their avrs, tvs, projectors, or dedicated scalars which are far superior at converting input speeds to what the display device needs to show it. It's an area of the sigma chip there is no way to improve unless it's a bug happening before the scalar touches it.

[digitalman]

yah i thought the stuttering definition was important, i didnt want it confused with frame judder or something like that from mismatched frame rates. for me when bitrates get too high the main thing is audio cuts out and video starts drawing 2-3 frames per second. until the bitrate drops then it goes back to normal and audio comes back. that is typical for VBR files that go just over the bandwidth threshold.

[Dave_D]

Quote:Part of your "findings" is actually why so many people want the auto-resolution option. It would allow the pch to not scale the video and optimally output it so people can use the scalars in their avrs, tvs, projectors, or dedicated scalars which are far superior at converting input speeds to what the display device needs to show it. It's an area of the sigma chip there is no way to improve unless it's a bug happening before the scalar touches it.

Learned something new today.

Thanks accident.

In a nutshell that means if the PCH doesn't scale the video output, content lower than 1080p resolution will be sent out the HDMI "as-is", lowering the computing requirement on the media player box.

This could solve a lot of framerate sync/video drops because nearly all TVs now have internal scalers at the bare minimum.

[Willem53]

Isn't there a routine that uses the HDMI information the display gives over it's total set of capabilities that would allow the C200 to send out "as is" when it matches the capabilities set.
I'm wondering if that is implemented with the new SDK or that we are still scaling to whatever 1080p/24/50/60PAL/NTSC is put in SETUP or a mix of both....

[chris57]

(05-27-2011 05:51 AM)Dave_D Wrote:  Learned something new today.

Thanks accident.

In a nutshell that means if the PCH doesn't scale the video output, content lower than 1080p resolution will be sent out the HDMI "as-is", lowering the computing requirement on the media player box.

This could solve a lot of framerate sync/video drops because nearly all TVs now have internal scalers at the bare minimum.

You would want the NMT to output at the correct fps if just using a TV. For those with decent scalers in AVR's or separate scalers it's wanted not those that just have a TV.

[accident]

(05-27-2011 05:51 AM)Dave_D Wrote:  In a nutshell that means if the PCH doesn't scale the video output, content lower than 1080p resolution will be sent out the HDMI "as-is", lowering the computing requirement on the media player box.

Anything I answer to this would be a pure guess, I never really compared cpu usage of the pch watching different bitrate originals with different output settings. I would assume no as the scaling is happening on the output side but again a guess.

Quote:This could solve a lot of framerate sync/video drops because nearly all TVs now have internal scalers at the bare minimum.

well not just tvs, but yes there are certain issues that could be fixed by having the player not scale the video when possible. Not to mention the quality tends to increase.

[jj666]

Both good disks for testing, looking at the bitrate spikes.

Baraka:



Depeche Mode:



Personally, I've found 1080p60 works as a solution for playback for all different content without issues on my TV (NFS between the servers and SMB to the C-200).

Cheers,

-jj-

[digitalman]

So which setting should be used in the video zoom option? If i am watching 1080p content on a 1080p projector? I have it set to fit to screen, should i be set to actual size? maybe fit is doing processing?