[ayampols]

Hi Everyone,

I've got a question about PS3's implementation of its DLNA client. I have tried using the PS3's DLNA client with a variety of desktop-hosted DLNA servers, and occassionally experience stuttering of the video stream. It can happen sporadically for the same piece of content. The video plays perfectly if copied and played directly off the PS3's HDD. Most of the video I stream is h.264 encoded, typically at level 4.1, and I cannot discern a pattern that might point to a problematic content type. A typical example, reproduced today, is of a 2 hour color video, whose bitrate ranged from about 2.1 - 4.5 Mb/sec. The desktop's CPU always holds steady, at about 15-18% utilization. The CPU utilization does not spike at all during the moments of stutter. So I began to look into what might be causing this, and started with the network utilization.

My network is straightforward: the PS3 is wired, via gigabit ethernet, to a router. Besides the desktop and PS3 there are no other devices on the LAN. The file copy operation shows a steady 3.5 MB/sec upload speed, flat as a pancake. The DLNA stream also uploads at a steady 2.5 - 3 MB/sec, with the exception of occassional drops which correlate to the moments when the video playback stutters.

I would very much like to understand why the DLNA stream uploads at approximately 6-8 times the bitrate of the video itself. Why does the video stream use up so much bandwidth? I have performed tests of alternate protocols on the same host, over the same network, using video clients such as VLC or QuickTime player. If I stream that same video via rtsp (e.g., QuickTime Streaming Server), the upload rate is only about 0.3 - 0.5 MB/sec (matching the bitrate of the video as expected), without any stutter at all. If the video is treated to support progressive download and hosted by a regular http server (apache), that same file streams at only about 1.7 MB/sec. And as expected with progressive download, there is no stuttering as the video is essentially played off of the client's local HDD cache. I have even gone so far as to experiment with sharing the video's folder using SMB or AFP. Even this method -- the least optimized for the use case -- shows the expected 0.3 - 0.5 MB/sec network utilization.

So what is the PS3 doing with all that data that is streaming to it? It doesn't seem to be buffering to disk, and it's clearly not buffering all of it into memory.*I sense that I'm missing or misunderstanding a key part of the mechanism. I would appreciate any insight into this!

Many thank in advance,
-Armen

[Uridium]

Which DLNA streaming apps have you tried?

[ayampols]

Originally Posted by Uridium

Which DLNA streaming apps have you tried?

Hi Uridium!
Thanks for getting back to me so quickly. I have tried many different DLNA media servers on a variety of platforms, but I have valid comparison metrics taken under controlled tests for the following three implementations:

mediatomb 0.11.0
NullRiver MediaLink 1.7.2
Elgato eyeConnect 1.6.3

All three show the behavior I ask about in my post -- a streaming upload rate greater than the copy rate, and 6-8 times greater than the bitrate of the video.

I would like to also provide these metrics for shagrath's "PS3 Media Server," but the application causes the PS3 to show error messages for my test video, and forces me to use one of its transcoding functions in order to stream properly. Although this option does not result in the behavior I ask about in my original post, it is not an apples-to-apples comparison, so I cannot include it in my list. The transcoded video takes up a fraction of the upload bandwidth, and also uses up almost three times the CPU utilization. It also yields a totally different playout bitrate.

I want to stress the point that I am not looking for a solution to my stuttering problem. Although it's tempting to recommend alternatives to my OS/chipset/network/transcoder, a separate post would be the fair thing to do for such a thread. My question is only about PS3's DLNA client implementation. I would love an explanation for the extremely high upload rates I am observing. And I'd love to know where all those bits are going.

If anyone is interested in more specifics about the metrics or the test video, just ask and I'll provide.

Thanks!
-A.

[ayampols]

Originally Posted by Uridium

Which DLNA streaming apps have you tried?

Originally Posted by ayampols

[I wanted to try] shagrath's "PS3 Media Server," but the application causes the PS3 to show error messages for my test video

I have now successfully repeated the test with PS3 Media Server and Yazsoft Playback. (Build 367 of the PS3 Media Server allows one to stream previously transcoded video without additional transcoding.) I can report that I continue to see the NIC upload at a rate of 4-7 MB/sec for the same test video -- a video that the PS3 reports to have a bitrate averaging 3-4 Mb/sec for its video, and around 128 kb/sec for its audio. Over the course of a two hour movie which takes up under 2 GB on disk, my network logger reported that the media servers streamed over 50 GB of data to the PS3. Each of the five tested media servers behaved in this way. Does anyone have any idea what the PS3 is doing with all that data?

[VisibleGuy]

Simply put the PS3 has a bug in it when streaming MP4 files where for some reason it forces the PC to stream at a much higher bitrate than the actual video. This is easy to prove by comparing network throughput streaming the same file to a PS3 and then a 360, the PS3 has a much higher throughput whilst for the xbox the throughput is roughly equal to the bitrate of the video.

Let's hope Sony fix this soon.

[marctwo]

I assume this is the issue I am suffering from. MPEG2 files stream file over 85mbs homeplugs but MP4 files stutter. Would 200mbs homeplugs be fast enough to avoid this issue?

[ayampols]

Originally Posted by VisibleGuy

the PS3 has a bug in it when streaming MP4 files [...] This is easy to prove

Indeed, and for those who do not have access to an XBOX, a very simple way to prove it would be to download and install the XBMC media player to any other computer on your network, stream from your media server as you would using the PS3, and compare bandwidth utilization. The bandwidth will be only slightly higher than the bitrates of the video and audio, nothing like the 20x premium imposed by the PS3. A truly shameful implementation from Sony.

Originally Posted by marctwo

Would 200mbs homeplugs be fast enough to avoid this issue?

My media server runs on a Mac connected to the network via 802.11n at 5GHz (the PS3 is connected to my router via gigabit ethernet), and note the bandwidth for a 2-4 Mbps file hovering between 4 and 9 MB/sec. I almost never get any stuttering at all. If I were to try that on a 802.11g wifi connection I would certainly see stuttering. What is the reported bitrate of your video and audio streams?

[types474]

Sony introduced this problem with v2.7 firmware so it's been around a while. I've been posting about this h.264 problem for a while but all I hear is use PS3 Media Server and transcode code to mpeg 2. Problem is I stream from a NAS box which I cannot transcode on.

It has got to the point where the family don't trust streaming as it randomly stutters. Currently working on a XBMC setup as described here which is much more stable and prettier.

SORT IT OUT SONY!!

[Uridium]

Originally Posted by types474

Sony introduced this problem with v2.7 firmware so it's been around a while. I've been posting about this h.264 problem for a while but all I hear is use PS3 Media Server and transcode code to mpeg 2. Problem is I stream from a NAS box which I cannot transcode on.

It has got to the point where the family don't trust streaming as it randomly stutters. Currently working on a XBMC setup as described here which is much more stable and prettier.

SORT IT OUT SONY!!

I've only ever seen this as an issue with MP4. Are you saying it happens with other Media types?

imo MP4 is a crappy format anyway...I steer clear and have trouble free streaming as a result

[ayampols]

Originally Posted by Uridium

imo MP4 is a crappy format anyway...I steer clear.

Ouch, sucks for me and my terabyte-sized video library. :-(

Could you share your reasons behind your criticism? Is it just the container format that you feel isn't up to snuff? What should we all be using instead?

[types474]

Originally Posted by Uridium

imo MP4 is a crappy format anyway...I steer clear and have trouble free streaming as a result

Whether I choose mp4, mkv, mpg container files is not relevant. I see no reason to re-rip my DVD collection because Sony have screwed up h.264 streaming playback in firmware >v2.7.

[ayampols]

Originally Posted by types474

Whether I choose mp4, mkv, mpg container files is not relevant. I see no reason to re-rip my DVD collection because Sony have screwed up h.264 streaming playback in firmware >v2.7.

Very well said.

But I also can't help but be curious as to why anyone would think mp4 is substandard. I work in the media industry, and have never encountered criticisms or problems. Can someone share some pointers?

[Uridium]

Originally Posted by types474

Whether I choose mp4, mkv, mpg container files is not relevant. I see no reason to re-rip my DVD collection because Sony have screwed up h.264 streaming playback in firmware >v2.7.

It is the container that's the issue though. 90% of my 4tb library is H264 .Vob and i get NO stuttering at all.

No Sony shouldn't have screwed MP4 streaming but they did and until they fix it the only solution is to use a different container.

Maybe it's just a personal opinion but I've always just seen MP4 as a 'portable' format' so i tend to avoid it. Appreciate this may not be correct but it is as i said just my opinion.

[ayampols]

Originally Posted by Uridium

Sony shouldn't have screwed MP4 streaming but they did and until they fix it the only solution is to use a different container.

But that's not true. You yourself provide an alternate solution in your PS3 guide -- use the transcode feature of PS3 Media Server. I have another solution -- use a network that has the bandwidth to handle Sony's bug: my 802.11n network has no stuttering issues at all. In my tests I have found that a network with >20x the bandwidth of the video's bitrate can handle the bug in stride.

If tomorrow Sony released a software update that fixed their mp4 bug but introduce a similar bug which would screw VOB streaming, what recommendations would you offer the forum?

[Uridium]

Originally Posted by ayampols

But that's not true. You yourself provide an alternate solution in your PS3 guide -- use the transcode feature of PS3 Media Server. I have another solution -- use a network that has the bandwidth to handle Sony's bug: my 802.11n network has no stuttering issues at all. In my tests I have found that a network with >20x the bandwidth of the video's bitrate can handle the bug in stride.

If tomorrow Sony released a software update that fixed their mp4 bug but introduce a similar bug which would screw VOB streaming, what recommendations would you offer the forum?

Transcoding is a workaround, not a solution. And it's not my guide; I was just a contributor. I already run a fully wired gigabit LAN.

Many people have had stuttering issues even when playing back MP4 from the int HDD on the PS3 so MP4 has other issues on top of it's bandwidth hogging.

Anyhow....tiring of your nitpicking posts now.

Won't be repling any further...

[ayampols]

Originally Posted by Uridium

it's not my guide; I was just a contributor.

Hey I'm really sorry about that -- I saw it in your sig and assumed you wrote it It's a great guide, though! I highly recommend it, and really appreciate whatever contribution you made.

For those who have serious interest in my OP and who are not squeamish when it comes to detailed, rigorous discussion, please write with your observations, ideas, and thoughts on the issue. From what I've heard on this and other forums, this is a serious matter that affects many users, and visibility can only help our cause.

[marctwo]

Well my mp4s are now playing fine. The only thing that has changed is that I upgraded to the new 3.1 firmware on the PS3. When I first did the upgrade, this was the first thing I checked, and it still stuttered on mp4 files. However, I don't think all the new features work properly immediately after the upgrade as iPlayer was also missing. When re-starting again iPlayer was back and my mp4s also started working again. Has anyone else noticed this?

[marctwo]

MP4s stuttering again. Can't work out what has changed. Also getting bluetooth connectivity issues since 3.10. Sort it out SONY

[brunetel21]

I have also problems with streaming mkv to the PS3 via the PS3 Media Server, the movie just won't play, it will shutter continously.
I use 85Mbps homeplugs to conect the ps3 to the router.
On my info screen on the right corner i get speeds of around 100Mbps sometimes even 115Mbps, that is way too much for a 720rip.

[Axum]

Are you playing the mkv from the transcode folder ? Does your pc have enough grunt to be able to do this on-the-fly ?

It might be worth pre-converting a 720p file (which will only take minutes if it's just an audio remux that's needed) with mkv2vob, then try and stream the resultant file over...see if that plays ok...

[marctwo]

Well, after some investigation I found why my videos were stuttering. It was because I had my one of my homeplugs plugged into an surge protected extension board. I changed it to being plugged directly into the wall socket and everything plays perfectly now. This must have cut the transfer speeds to the point that mpegs would still play but mp4 files would not.

[twobells]

Originally Posted by marctwo

I assume this is the issue I am suffering from. MPEG2 files stream file over 85mbs homeplugs but MP4 files stutter. Would 200mbs homeplugs be fast enough to avoid this issue?

No, I have the current fastest homeplug (Panasonic PowerBridge) and its a shame but for some reason .mp4 is plain broken on the PS3.
Every other format up to and including 1080P mkv files with DTS all work perfectly but not .mp4.
The throughput is astonishing, sometimes as much as 75GB for one short film!

[Christ]

I use ps3mediaserver connected to an iMAC running SNow Leopard and have exactly the same issues with mp4's.

Heres some examples.

mp4 585kbps - ok
mp4 6.4 mbps - stutters badly
mpg 3.0 mbps - ok
mpg 10 mbps - stutters badly

This is all using Zyxel 200mbps homeplugs, if I connect the systems using cat5 to a 10/100 router the problem goes away.

Think Im just going to do away with the homeplugs.

[marctwo]

I upgraded to some ebuyer 200mbs homeplugs and everything works perfectly, even 1080p mp4 files at 10mps. I hope you guys get it working soon.

[brunetel21]

Originally Posted by marctwo

I upgraded to some ebuyer 200mbs homeplugs and everything works perfectly, even 1080p mp4 files at 10mps. I hope you guys get it working soon.

Did you have slower home plugs before? because I just bought my 85Mbps plugs, so don't tell me that I have to trash them and buy a new set.

[Uridium]

Originally Posted by Christ

I use ps3mediaserver connected to an iMAC running SNow Leopard and have exactly the same issues with mp4's.

Heres some examples.

mp4 585kbps - ok
mp4 6.4 mbps - stutters badly
mpg 3.0 mbps - ok
mpg 10 mbps - stutters badly

This is all using Zyxel 200mbps homeplugs, if I connect the systems using cat5 to a 10/100 router the problem goes away.

Think Im just going to do away with the homeplugs.

Or do away with MP4

[Christ]

Originally Posted by Uridium

Or do away with MP4

And .mpg...

I just ran cat5e in the end, everything works perfectly

[Axum]

mpg is fine, nothing wrong with that...

[marctwo]

Originally Posted by brunetel21

Did you have slower home plugs before? because I just bought my 85Mbps plugs, so don't tell me that I have to trash them and buy a new set.

I had 85s before. I suspect it rather depends on the speeds you are getting through your wiring though as I had SD mpegs and mp4s working fine, it was only the HD stuff that stuttered. Make sure you plug them into the wall socket and not an extension socket. However, even like this you may not get HD streaming working. I think 200mbps ones are the way to go.