Wowza Community

Recorded stream low FPS: server/wowza issue or client side issue?

Hi there,

I am using Wowza mainly to record incoming video streams from webcams. However, I have a lot of the video’s with a very low FPS rate (lower then 10 FPS, some video’s are even as low as 4 FPS).

In the beginning I thought this was a client side issues. Initially, I thought I tried the recording quality (640x480) was too much for some clients too handle. Especially when the user had a webcam with a lower resolution. Therefore, I lowered the default recording quality to 320x240, plus I lowered the keyframe rate to 1 keyframe every 30 frames (to save bandwidth).

However, the problem persisted. Then I started considering the issue might be related to a low-end CPU and/or low bandwidth availability. So, I lowered the minimum accepted recording quality (using the AS3 method netStream.setQuality) and maximised the bandwidth that can be used by the client. Both measures, should (theoretically) prevent frames from getting dropped.

Again the problem the persisted. Recently, we had a user with the same issue, who was using the latest Macbook Air. Which excludes in my opinion the possibility that a low-end CPU might be causing this issue. Also, this user had a very decent bandwidth available (I am checking and storing this as well). So, I am running out of option what might causing these frames to drop.

I am hosting the Wowza DVR instance on a VPS (2 CPU, 4 GB RAM). I know, this is lower then the minimum Wowza requirements. However, the CPU usage did not ever exceeded 10% in the last 1 month. So, to my knowledge Wowza performs okay on this VPS.

My question: can anyone exclude that this issue might be related to the server or Wowza intance?

Thanks in advance!

Ron

Hi,

When recording to nDVR it requires very high disk I/O performance to ensure that multiple streams can be written and read simultaneously.

If you are having issues mainly with the recording and not necessarily with the resultant live streams, then this could be the issue.

Daren