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mroek

Dahua HFW2100 - what could cause this?

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What I noticed (from the live tab in the camera web interface), was that the reported bit rate was around 1700 kbps. Resolution was showed as 1280*960. What I did then was to change the bit rate to CBR (still 4096). The actual bit rate then jumped to the expected 4000-4100 kbps, but the image quality remained the same, i.e smeared details and slightly low color saturation. I tried changing bit rate (and mode) back and forth a few times, but while the actual bit rate changed, the image quality was still bad.

 

Be sure to check the CBR/VBR settings for both general and motion stream!

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OK, so one of my cams decided to send 150+ motion email jpegs to me last night. All of no noticable motion. Even with sensativity 1 and anti-dither 1(I assume anti-dither means if motion last longer than X"). This might be those mystery rendering or exposure articacts. So what would the best settings be to reduce these false alarms? VBR vs CBR, higher bit rate or frame rate, gain setting? The lowest sensativity on these cams is to sensative or the algorithm sucks.

 

Note that I use the camera onboard config to send emails, not the NVR becuase the NVR can not send a camera specific subjects.

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Best is CBR, 8000 (custom), 25fps, highest resolution.

 

Anti-dither, for now, works as a "smallest size of a recording".

 

Please be aware that motion detection uses differences between frames, so light changes, wind, even some pixel changes during compression can trigger a motion detect.

 

Also, try to set it to 6 to see what happens.

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Anti-dither, for now, works as a "smallest size of a recording".

 

Can you clarify the meaning of this antidither setting a bit more?

 

Thanks.

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If motion is for 1 sec, for example, the device will record at least X seconds (the min value should be 5 seconds).

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If motion is for 1 sec, for example, the device will record at least X seconds (the min value should be 5 seconds).

 

I thought it meant, don't trigger motion until motion has been constant for X seconds. So this could filter bugs flying by or other quick frame differences. So the bigger the number the longer it waits to trigger. Is this not true?

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Just one more update from me on this:

 

I studied this a bit more yesterday, and I have come to the conclusion that the issue is probably caused by an overly aggressive noise reduction algorithm. Noise reduction is known to also kill details, so that makes perfect sense. The problem here is that we have no manual control of this algorithm. It would have been nice to be able to adjust the parameters for this algorithm.

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I'm using firmware version 2.100.0001.0.R, build : 2012-10-31 but I have noticed it on other versions. Doesn't happen all the time. Seems very random.

 

I have seen this many times on my HFW2100 cameras. I notice it most in the mornings when the sun is rising.
Which firmware do you have on those cameras? If it is an older version, it means they (Dahua) haven't been able to (or tried) to fix it either, even though I am certain that it actually is a quite simple thing to fix.

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I'm using firmware version 2.100.0001.0.R, build : 2012-10-31 but I have noticed it on other versions. Doesn't happen all the time. Seems very random.
Same firmware as me, then. Yes, it is kind of random, which makes it even more irritating. Another thing I'd like to have more control over is how quickly the camera adjusts exposure. I am getting a number of false motion detection alerts because the camera has a tendency to adjust exposure and/or gain a bit too much up and down, especially at dusk and at dawn, when the sun is rising or setting. Had the camera adjusted more slowly, I'd have gotten fewer alerts.

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Yeah, this looks like a firmware bug. Dahua's firmware is not their high point - it's buggy and glitchy, there's no control over key items, and they don't fix bugs very often.

 

I'd be interested in getting a copy of this firmware, if anyone can post it somewhere. I'm on the previous version, and would like to try it out.

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Today one of my cameras stayed in the noise reduction mode even after there was normal daylight outside. This is really annoying, and I strongly feel that Dahua should give us a switch to turn off this noise reduction, or at least dial it down. Even at night, I don't mind some noise in the images, it is still way better than the smeared low-detail image that their noise reduction creates.

 

Moving the gain slider a notch and then back will turn off the noise reduction (but only temporarily, of course), but it really shouldn't be necessary.

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I get a few motion sent images from my several of my Dahua(Q-See) 1.3mp cams of over exposure. Seems like like the automatic control gets lost occasionally and this happens in the middle of the day.

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Dahua doesn't make firmware available to lowly end users. The official answer is to get it from your distributor; if that's not feasible (like if you bought a camera used or from someone who had extras), you ask on forums.

 

Same for finding out what the latest firmware is.

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