Noise lines during capturing
Noise lines during capturing
I installed latest MDK LiveCD with a one Conexant chip and 4 inputs capture card.
If I see monitor in higher resolutions (surely >=640x480) in RGB* mode I got a lot of noise horizontal lines when ther's movement in the image.
It's a Zoneminder fault cause I get an excellent image if I look it at 640x480 or more with xawtv (or tvsomething can't remember well).
Setting grab image to 352x288 or less I don't get any artifact.
What could cause the problem? I get those lines even in stil frames so it's as zmc can't capture correctly frames at those resolutions.
Machine is a P4 2.4 Ghz with 512 MB Ram and I'm usting it with only one cam so I don't think it's a load problem (load is variable from 0,5 to 1.2, with X running).
Francesco
If I see monitor in higher resolutions (surely >=640x480) in RGB* mode I got a lot of noise horizontal lines when ther's movement in the image.
It's a Zoneminder fault cause I get an excellent image if I look it at 640x480 or more with xawtv (or tvsomething can't remember well).
Setting grab image to 352x288 or less I don't get any artifact.
What could cause the problem? I get those lines even in stil frames so it's as zmc can't capture correctly frames at those resolutions.
Machine is a P4 2.4 Ghz with 512 MB Ram and I'm usting it with only one cam so I don't think it's a load problem (load is variable from 0,5 to 1.2, with X running).
Francesco
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xawtv, tvtime etc use deinterlacing techniques to stop this happening.
This is a common question use the search the fourum buttin and search for interlace
http://www.zoneminder.com/forums/viewto ... =interlace will get you started
Some chips are better than others but if you are getting 'combing' even without movement, lazyleopard wrote a nice mod that phil added in 1.21.3
The setting is in options somewhere
James
This is a common question use the search the fourum buttin and search for interlace
http://www.zoneminder.com/forums/viewto ... =interlace will get you started
Some chips are better than others but if you are getting 'combing' even without movement, lazyleopard wrote a nice mod that phil added in 1.21.3
The setting is in options somewhere
James
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As I've just mentioned in another reply strangely enough, xawtv etc in normal mode just use a memory mapping technique to map the video memory to screen memory. In order to analyse an image ZM (and other applications) have to grab each frame separate using a different method. In xawtv you can simulate this by doing a few image/frame grabs and saving and examining those images.
I would be interested to see whether any of those images exhibit the same problem. A couple more example images might also be useful.
Phil
I would be interested to see whether any of those images exhibit the same problem. A couple more example images might also be useful.
Phil
I didn't still solved but I'm now trying to see if it happens with a different bttv grab card (It's a TV Card I've got). Let you know soon.
Phil as you see with tvtime I don't have such noise, have you got some idea about that problem? It's something only I have to fight with or you already had seen something similar?
Phil as you see with tvtime I don't have such noise, have you got some idea about that problem? It's something only I have to fight with or you already had seen something similar?
I've found some more info about the card I'm using. It's a Hawell DVR Card Hw-104, you can find some specs here:
http://www.alibaba.com/catalog/10985937 ... w_104.html
I tried using 768x288 and lines disappeared. So that problems seems visible when vertical resolution is > 288... (as you can see in screenshot they appears only in the first half of the image, never below, I forgot to say this particular in my post).
http://www.alibaba.com/catalog/10985937 ... w_104.html
I tried using 768x288 and lines disappeared. So that problems seems visible when vertical resolution is > 288... (as you can see in screenshot they appears only in the first half of the image, never below, I forgot to say this particular in my post).
Hi,
This card is also known as PICO2000. They are lot of clone all over the world
Why do you want to use it in a resolution higher then 384*288 ?
Personnaly, for CCTV it's more than enough.
Regards,
Oliver
________
Mercedes-Benz 200 History
This card is also known as PICO2000. They are lot of clone all over the world
Why do you want to use it in a resolution higher then 384*288 ?
Personnaly, for CCTV it's more than enough.
Regards,
Oliver
________
Mercedes-Benz 200 History
Last edited by RedFlyer on Mon Feb 14, 2011 5:17 am, edited 2 times in total.
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i think if you feed progressive scan into it you should be ok. I am supposed to be testing this. Else go for IP camera. Im gonna trial a 206M to see how megapixel performs as i think this is the way to go. Unfortunatly is zm is analysing images of this size i think the overhead maybe too high. Someone else came up with the grat idea of sampling down to a low res just for movement analysis. If Phil impliments this then this will without doubt be the way to go.
James
James
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