8 channels BT878 card : max resolution issue

[jack burton]

Hi all,
yesterday i've installed zoneminder 1.25 on debian wheezy, on a pc equipped with a pci 8 channels (8 chip) bt878 card from camsecure.
I succesfully configured the card and i'm able to watch 8 channel at 320*240 resolution using preconfigured settings from "add monitor" menu on zoneminder, choosing bttv, v4l2, 320*240.

I can't set the card to capture frames at resolution bigger than 320*240, if i try to set 640*480 the "dev/videoX" on main page becomes red, and i can't view no image.

Is there any other parameter to set in zoneminder config to achieve a bigger resolution ?

Thank you.

[mikb]

I think that resolution limit is something to do with interlacing vs non interlacing images.

The BT878 has 2 capture engines. For interlaced pictures, each engine does odd (or even) fields of the frame. While one is capturing, the other is offloading to system memory. That's for resolutions over (I think) 384x288.

But at 384x288 and under, each capture engine can be used separately (e.g. separate physical inputs 2 at a time, or one capturing input to memory and one capturing input directly into screen memory in hardware overlay mode -- ZoneMinder doesn't use that, but it's possible in the hardware).

You sound like you are pushing the hardware cap card too far with 8 inputs in full resolution!

[jack burton]

Hi,
i increased the shared memory, and now i'm able to view 2 cam at 640*480, 20fps each one.
The image quality is poor, when i move something in front of the camera i can some rows like there was interlacing problem.
Is there any specific option to fix this ?

P.S: I also tried succesfully to view 2 camera live stream in swf, but a very high delay. I'll try to play with cache settings

thank you.

[mikb]

Hi,
i increased the shared memory, and now i'm able to view 2 cam at 640*480, 20fps each one.
The image quality is poor, when i move something in front of the camera i can some rows like there was interlacing problem.
Is there any specific option to fix this ?

P.S: I also tried succesfully to view 2 camera live stream in swf, but a very high delay. I'll try to play with cache settings

thank you.

Does the messy interlacing mess at http://www.zoneminder.com/forums/viewto ... 30&t=21709 look familiar? Or is it a more orderly "it's just interlacing out of order" kind of effect (comb effect)?

[jack burton]

Hi,
i increased the shared memory, and now i'm able to view 2 cam at 640*480, 20fps each one.
The image quality is poor, when i move something in front of the camera i can some rows like there was interlacing problem.
Is there any specific option to fix this ?

P.S: I also tried succesfully to view 2 camera live stream in swf, but a very high delay. I'll try to play with cache settings

thank you.

Does the messy interlacing mess at http://www.zoneminder.com/forums/viewto ... 30&t=21709 look familiar? Or is it a more orderly "it's just interlacing out of order" kind of effect (comb effect)?

I think i have the same problem, even if i'm running zm 1.25 . I have the same artifacts on each frame every time there's a movement.
Tomorrow i'll try to apply the settings suggested by mastertheknife in the post you linked, and i'll let you know.
Thank you, goodnight