Strange "not in sync" frames

x-fede · Post by **x-fede** » Sun May 30, 2004 11:49 pm

Hi,

Sometimes I've weird events, with frames in the wrong position.
It looks like some frame is missed and then saved too late.
It's hard to explain in proper english, but I've a sample mpeg.

http://www.virgolanet.net/Event-26.mpg

You can see the problem when I jump (poor performance, I know...!), around the half of the file.

thanks

djsb · Post by **djsb** » Sun May 30, 2004 11:50 pm

please see the previous post.. i've reported the same with a little more detail...
See if you have the same problem...

x-fede · Post by **x-fede** » Mon May 31, 2004 11:12 am

In my case, even inside one frame there are "mixed frames".
Look at this one:

It looks like two frames have been mixed: one with the car and one without (look carefully on the left, you can see the little wall throu the car...!)

lazyleopard · Post by **lazyleopard** » Tue Jun 01, 2004 5:34 pm

What resolution are you using? What sort of frame-rate? How many separate inputs on the one chip?

It looks rather like a severe case of one bttv chip trying to cope with multiple inputs. When you switch from one input to the next it takes a finite time to settle down. If you're using a resolution that requites an interlaced frame then the problem's magnified.

Post by **zoneminder** » Tue Jun 01, 2004 7:57 pm

Do you have more than one camera on the same device?

Phil,

ps. Nice looking house by the way!

lazyleopard · Post by **lazyleopard** » Wed Jun 02, 2004 10:17 am

...and how long is the cable run from the camera to the video card, and is the cable and the connectors on each end the right impedance? Some of the image-doubling (a subsidiary problem, not the main one) may be down to an echo on the cable, which may be down to a poor connector at one end or the other....

x-fede · Post by **x-fede** » Thu Jun 03, 2004 2:44 pm

only one camera per chip/input.

the cable is very long, and that's the cause of the bad video quality (the "double" edges), but still the main problem I'm trying to fix is the fact that frames are out of sync... please look at the mpeg video in my previous message: it's better than the still image to understand the problem.

I THINK it could be a buffer-ring problem.. I'll do some tests changing the value.

anyway, I'm using 352x288, 24bit with a spectra8 board.

Post by **zoneminder** » Thu Jun 03, 2004 2:49 pm

I've had a look at the MPEG above and I can't really see what it is that we're trying to find. It looks like it's only two frames or so and the first is blocky (by compression) and the second looks ok. I don't see any out of sync'ness on it.

Am I missing something?

Phil,

x-fede · Post by **x-fede** » Thu Jun 03, 2004 4:36 pm

Look at this:

it's a mix between two frames: one when I was still walking and one while I was jumping (about a couple of seconds later). The problem is also in the frame (images) on the server, not just in the mpg file.

I hope I'll be able to do some more tests on Sunday.

x-fede · Post by **x-fede** » Fri Jun 18, 2004 9:30 am

New examples. Problem still not solved

Video is here: http://www.virgolanet.net/Event-320.mpg

Carbide_tipped · Post by **Carbide_tipped** » Wed Aug 11, 2004 11:54 am

Try a lower res. like 320x240. I had the same problem.