Ignore packet because its is massively negative

[ibrewster]

In looking at my Zoneminder log, I see a ton of entries like the following:

Code: Select all

2021-01-19 14:22:01	zmc_m4		2365247	WAR	Ignore packet because pts -102385 is massively negative. Error count is 0	zm_ffmpeg_camera.cpp	770

I was wondering what might be the cause of these entries, and how to "fix" them, assuming they are fixable and not just "normal" operation? They are all for the same monitor (m4), and the error count varies between 0 and 1.

[Magic919]

It's the camera and not ZM.

[ibrewster]

Thanks for the information. Unfortunately, that doesn't help me fix the issue

[Magic919]

I’m not sure what you are expecting. You have a warning in the ZM logs that are caused by the camera.

[ibrewster]

Well, I was kinda *hoping* that a) someone knew what caused the error ("the camera" doesn't answer that - what *about* the camera causes that?) and, more significantly, b) how to *fix* the problem, assuming it is fixable. I guess I was hoping for too much. Is this forum only for general discussion, and not getting help with identifying and fixing issues?

[Andyrh]

This forum is for getting excellent help with ZoneMinder. When possible help is given for Unix, networking and cameras.
Unfortunately there are far too many cameras to expect detailed help on a particular one unless someone else happens to have the same brand. A search from the manufacturer may yield help or a forum for that brand of camera.

I am not aware of my Amcrest cameras generating that error. So I cannot help.

[Magic919]

Let's take it bit by bit.

There are warnings in the log that have no impact on ZM and you may not even spot the problem in the streams.

The error is saying that the metadata relating to the timing of video essence is showing a hugely negative timing value (which is spurious). This is the Presentation Time Stamp if you wish to look at it and it relates to when the video frames should be shown on the device.

The ZM devs have decided, rightly, to just ignore the packet with the spurious value and to chuck a warning in the logs. Depending on the incoming stream type is probably in the region of 188 bytes of data.

The camera maker would need to sort this out in their firmware.

[ibrewster]

Let's take it bit by bit.

There are warnings in the log that have no impact on ZM and you may not even spot the problem in the streams.

The error is saying that the metadata relating to the timing of video essence is showing a hugely negative timing value (which is spurious). This is the Presentation Time Stamp if you wish to look at it and it relates to when the video frames should be shown on the device.

The ZM devs have decided, rightly, to just ignore the packet with the spurious value and to chuck a warning in the logs. Depending on the incoming stream type is probably in the region of 188 bytes of data.

The camera maker would need to sort this out in their firmware.

Thank you! That is quite informative, and answers the question (it's not fixable, nor is it something to worry about). Given that information, is there a way I can suppress this particular warning in the log? No worries if not. Thanks again!

[Magic919]

I don't run 1.34.x but I doubt there would be an easy way to hush just that error.

For clarity, you could edit zm_ffmpeg_camera.cpp to prevent it logging the warning by commenting out Warning("Ignore packet because pts %" PRId64 " is massively negative." . I'm not suggesting that.

[iconnor]

I have actually removed that code in master. Havn't gotten around to merging it to 1.34. Wasn't sure it was ok.

I havn't seen any side effects. negative pts is actually possibly valid especially with h265.