Video stuttering

[Daniel Nielsen]

Hello all,

I manged to build a 5 x 1 wall setup.

With a master Pi streaming the video.

The video is sized to full HD and the buffer_size option is set.

Yet every second the video stutters. any ideas ? I can't access the pi setup from here but every time I google the issue I end up in this forum in a post where the buffer size was incorrectly set (buffer=1200000B corrected to buffer_size=1200000B) but no positive reply.

seems like most people get it to work correctly using VLC, but this is not an option as this is a closed LAN loop.

where to find details/logs ? I see that it runs at 19 fps, though the video is 25 fps.so something is overloaded...but what ?

[Beau Rosario]

Hi! Did you ever figure this out?

I'm trying to play a simple 1080p 55mb mp4, and it's all stuttered.

[Matt Stone]

I'm having the same problem, I've not yet figured out why the video stutters but when I do I will post here as I have until the end of today to get it working in time for a show we are using a 4 screen PiWall at! We also have problems with video sync as appears to be lag between screens but I imagine this is related to the stuttering. What hardware are you using? We have 5 Raspberry Pi 3's so in theory memory/gpu shouldn't be the issue.

[Matt Stone]

Hi Daniel, I was able to solve my video stutter issue by running the video through Miro Video Converter on my Mac (it's also available for Windows too) and exporting the file as an MP4 without changing any of the default settings. So the issue seems to be something to do with the encoding of the video, perhaps the bitrate but not being an expert in the matter I can't say for sure. I converted the Big Buck Bunny test video (the .mov version from the website) and now that I've re-encoding it using Miro it's working almost perfectly.

You can download from here: http://mirovideoconverter.com

Let me know if this solves your issues too.

[Mateo Ferley]

I'm trying to make a 5x1 setup as well, could you please share you files with me? I'm trying to make it but with no luck, maybe your config file can help me. 

[Matt Stone]

Hi Mateo,

Our configuration was for the standard 2x2 setup and we actually found the default test (without configuration files) worked perfectly with our TV's and seemed to compensate for the bezel even though the documentation states that shouldn't be the case.

What is the exact problem you are having? I would assume with such a wide layout you would need video files in a very un-common aspect ration (80:9 assuming you have your displays side by side in landscape mode).

[Dennis Nygaard Nielsen]

This worked great for me! Though.. i dont hear sound anymore :/ What is your setting for master and slave?

Thank you so much

Dennis

[Dennis Nygaard Nielsen]

And that was to you Matt :)

[gef]

Hi Guys,

I'm putting together a 4-screens (2x2) PiWall... I seem to have it all sorted but like others, am suffering from some video stuttering. I've provided as much info as possible - hopefully it might help someone identify where the problem is coming from!

Hardware:

4x Raspberry Pi 3 Model B (for slaves and master). Fuly isolated network. IPs as per setup guide.

Running latest release or Raspbian light (Jessie 2016-03-18), with apt-get update/upgrade ran after installation

Test video:

  big_buck_bunny_1080p_h264.mov (http://download.blender.org/peach/bigbuckbunny_movies/)

  Video codec omx-h264 width 1920 height 1080 profile 77 fps 24.000000

Tests:

  omxplayer big_buck_bunny_1080p_h264.mov - Plays fine locally, no stuttering.

  pwomxplayer big_buck_bunny_1080p_h264.mov - Plays fine locally, no stuttering.

  pwomxplayer --tile-code=42 big_buck_bunny_1080p_h264.mov - Plays fine locally, no stuttering.

  MASTER: avconv -re -i big_buck_bunny_1080p_h264.mov -vcodec copy -f avi -an udp://239.0.1.23:1234

  SLAVE: pwomxplayer --tile-code=42 udp://239.0.1.23:1234?buffer_size=1200000B - Stutters!!!!

  SLAVE: pwomxplayer udp://239.0.1.23:1234?buffer_size=1200000B - Stutters!!!!

  At this point we see stuttering (with and without tile codes set), which would make me presume it's a network issue, as we've been 100% fine until we started using the network...BUT... If I try the following command on a slave (With the usual avconv master command, I can play the video without stuttering), which kind of proves that the network is OK?

  SLAVE: omxplayer -o hdmi udp://239.0.1.23:1234?buffer_size=1200000B

  The only problem with the above command is that it 'bombs out' after 15 seconds or so, and gives the dreaded "have a nice day" error.

As far as I can tell pwomxplayer seems to introduce the stuttering when using UDP video stream, as omxplayer grabs it fine. Is pwomxplayer just a front-end to omxplayer? Could somone suggest some omxplayer switches etc that would prevent it from crashing after 15 sec?

Thanks! :)

[Alex Goodyear]

Hi Guys,

I was hoping that one of you would think to look through the early forum posts because this has been covered many times before, see
https://groups.google.com/forum/#!topic/piwall-users/8XbMlTrYldg
https://groups.google.com/forum/?utm_medium=email&utm_source=footer#!topic/piwall-users/2y5P9cTTkbA

pwomxplayer is a heavily modified version of omxplayer that fixes various problems including not being able to play videos for more than 15 seconds or so. The fixes and libav libraries used make pwomxplayer more sensitive to oddly encoded videos.

Regards,

Alex.

[Matt Stone]

In fairness to the people on this post a search for 'stuttering' doesn't bring back either of those forum posts.

As stated in those posts and other answers the encoding of the video makes a big difference to how it plays back on a PiWall. Even the test video Big Buck Bunny does not play back correctly on multiple screens without first being re-encoded.

I used Miro Video Converter for Mac (there is a Windows version too) and exported an MP4 which played perfectly and wowed people passing our stand at a recent trade show (the video on-screen in this shot was a single file playing on a continuous loop achieved by using a bash script):

We didn't need a configuration file as despite what the documentation suggests the default 2x2 setup seems to account for a very small bezel (we selected low-cost televisions with the smallest bezel we could find for the price). All in the build cost us around £1600 which included all the Pi's, TV's, Wall Mount Cantilever brackets, network switch and cables. At some point I'll post some more photos of our build in a separate thread and share the bash script code which allows the system to run automatically even in the event of the power being turned off and back on.

[Hayden Myers]

I went through the exercise of patching the latest version of omxplayer with the piwall libraries.  I made it through, and am now able to play rtmp streams.  Were there changes made to the libav code?  The libav libraries are already compiled in the source pwomxplayer package.  Omxplayer has progressed a fair amount since the piwall project created a debian package.  

[Roman Mescheryakov]

Hi Hayden, could you please share the new version of pwomxplayer you created?

[Paul]

Thank you Matt, your instructions RE: using Miro Converter worked great for me!