Playback very bad, skipping frames, in spite of good recording speed

As I review alarms using Playback, the playback is very non-fluid, i.e. I get the impression that many of the recorded frames are skipped. I do not understand the cause and would like to learn what I should change (parameters, configuration, checks to make, etc.) in order to resolve the problem so that I can obtain a fluid playback when reviewing alarms.

The following describes my system and the checks I have already made, trying to identify the problem:

  • D16 night cam with 2 wide angle lenses
  • Synology NAS 1817 with 8 bays, 7 of which each have a 3TB WD Red, configured as RAID5. This system is quite fast with read and write speeds close to the capacity of my network. All cables are cat7 1Gbps
  • Cam settings: Image 6MP with quality set to high, recording speed 6fps
  • Network environments: I have both tried playback using the standard environment (via the cam) as well as a new environment I named server, which plays back directly from the NAS. Astonishingly no perceivable difference.

Hello @alpinemartin,
thanks for your request.

The playback in MxMC should normally work normal, so that you can see the recordings in a normal speed and everything that was recorded by the camera.

In this case maybe the camera has some problems to send all the data to the NAS and some files get lost.

We have to analyse this in our support.
Please contact the german support via mail: support-de@mobotix.com and mention my name Mx-MaikC. I will have a look into this file and will inform you about the analyses.

We need some file of your system for a better analyses.

  • Support-Information of the D16 (Admin-Menu: Download Support-Information)
  • MxMC Debug Logs -> MxMc -> Help -> Debug-> Debug-Logs -> Reproduce this issue -> Don’t close the MxMC -> Help -> Debug -> Open Log Folder
    => Please send us the following to Logfiles: MxManagementCenter and MxManagementCenter_IE

This is just to share a few observations, which have helped me to resolve part of my frame rate problems.

First of all, many thanks to Mx-MaikC and to Mobotix Support for taking time to provide very helpful suggestions to solve problems, even when these are sometimes “beginners’ problems”.

In order to better understand where the bottlenecks may be, I did a fair amount of experimentation and found the following steps to be quite useful:

  • I re-read the specifications and manuals for may cameras. This lead me to the surprise, that I should never expect more than at best 6fps with my settings (6MP, 60% JPG Quality)
  • I experimented with various settings for recording the frames to my Synology NAS. While doing so, I found that the setting, which worked best for me was to use the setting “Primary Target: Buffered MxFFS Archive” and “MxFFS Archive Target: SMB/CIFS File Server”. Before that, I had just recorded to SMB/CIFS File Server, which at best gave me 1 - 2 fps. I also experimented with very low Live Stream resolution and have now gone down to VGA, which gives me 5 - 6fps on the livestream. This combination gives me roughly 5 fps on the playback which is a lot better than the previous 1 - 2fps.
  • I also tried to check the bandwidth of my connections, switches and NAS and they all seem to give more than enough. At this stage I found the suggestions of MaikC very helpful, to insert the available frame rate as an information in the view. In addition, I inserted the data rate in the view.

Some small mysteries remain and I presume that I will find ways of resolving them too. In case anyone has hints to propose for the following, then I would be most interested:

  • how to insert a text in the recorded material? I would like to insert the frame rate used for the recording and the data transmission rate at the time of recording
  • what free tool (software for iMac) to use in order to measure the bandwidth from the cam to the NAS? This could help me identify potential bottlenecks in my LAN

I hope you will find this post helpful!