Getting "Unable to extract header from stream, retrying

dave_d · Post by **dave_d** » Mon Apr 26, 2004 4:32 pm

I've got this DLink DCS1000 camera. I tried to get it to work with a 0.9.n version of ZM but failed miserably. The posts at the time rather indicated that failure was more common than success and so I decided to wait a while before continuing with the surveillance project I was working on. Recent posts seem to indicate that most of the IP camera streaming problems had been solved. So, I rebuilt the Slackware box, got the latest 1.19.2 and built everything from scratch. I hooked up the DCS1000 and yes! - a video stream appeared.

I used i/p address, port = 80, source = /video.cgi and a picture size of 240X320.
I then added another camera running from a video card - and lost the i/p camera stream.

Since then I've tried everything including removing the database and rebuilding all ZM fom scratch. No more i/p camera stream!! All I get (occassionally and if I'm quick enough to #killall -USR1 zmc) is the error message "Unable to extract header from stream, retrying".

Can anyone shed any light here?

Regards,

Dave

dave_d · Post by **dave_d** » Tue Apr 27, 2004 9:12 am

Well, I managed to get it all working again - but I don't really have a good explanation of what happened. Here's what I did ...

1. remove the zm database
2. Apply the zm-1.19.2 patch
3. perl zmconfig.pl
4. rebuild the zm database
5. perl zmconfig.pl -noi
6. restart zm
7. check the camera and set the date/time (was a long time in the past)
8. make a monitor as described in the previous post

All works!!!!

The only other thing I found was a strange error message in the apache error log. The lines are:

[Mon Apr 26 17:36:53 2004] [error] [client 192.168.40.2] File does not exist: /var/www/htdocs/zm/com/charliemouse/cambozola/ViewerBeanInfo.class
[Mon Apr 26 17:36:53 2004] [error] [client 192.168.40.2] File does not exist: /var/www/htdocs/zm/com/charliemouse/cambozola/Viewer$COMClassObject.class
[Mon Apr 26 17:51:07 2004] [error] [client 192.168.40.2] File does not exist: /var/www/htdocs/zm/com/charliemouse/cambozola/Viewer$COMClassObject.class
[Mon Apr 26 17:55:10 2004] [error] [client 192.168.40.35] Premature end of script headers: /var/www/cgi-bin/zms
[Mon Apr 26 17:56:37 2004] [error] [client 192.168.40.2] File does not exist: /var/www/htdocs/zm/com/charliemouse/cambozola/Viewer$COMClassObject.class

You can see from the time stamps that these occurred during various attempts I made yesterday to get things going. I have no idea what these error messages indicate. Most puzzling is the fact that I've never had a directory called com/charliemouse!!!!

Phil ... any comment?

Regards,

Dave

Post by **zoneminder** » Tue Apr 27, 2004 4:15 pm

I think the

[Mon Apr 26 17:36:53 2004] [error] [client 192.168.40.2] File does not exist: /var/www/htdocs/zm/com/charliemouse/cambozola/Viewer$COMClassObject.class

error is just something Java'y. It's appending the class path onto the web path or something like that. I don't know a huge amount about the Cambozola applet but if it's working then that's the main thing. Did you rebuild it yourself or just use a ready made .jar file?

Phil,

dave_d · Post by **dave_d** » Thu Apr 29, 2004 4:57 pm

Hi Phil,

I used the Cambazola version I got from your web site eons ago - 0.22, IIRC!

Dave