In CBR mode, the encoder shouldn't care about B&W vs color. Depending on how they've setup their encoder, it might make a difference in VBR mode. You'd have to do a controlled test with the same scene to be able to tell for sure though. Because in VBR mode, the composition of the image, and the amount of motion is going to affect the bit rate as well.
Dahua 2MP 25x Starlight IR PTZ Network Camera (SD49225T-HN)
- Thread starter ldasilva
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That's interesting that you're getting different recording times, are you positive both are set to CBR? It could be their encoder just isn't very good at hitting its target bit rate (I come from the video processing world, not CCTV, so this amount of variance might be totally normal in this industry).Duhhhh... So I was typing faster than the ole noggin was processing
On the one cam at 8192/25fps CBR I'm getting not 18hrs but 1.5 days = 36 hours (had 12 hours in my head for some reason)
on the other at 8192/CBR 15fps i'm getting closer to 2 days or 44-48 hours
bigredfish
Known around here
Thanks!
bigredfish
Known around here
Yes both H.264H 8192 CBR with Iframe = to FPS. One at 25fps one at 15fps.
I just popped into both cams to see, the one running 15fps CBR is showing just shy of 2 days or 48 hr recording available in the playback timeline, the other at 25fps approx 36 hours...
I just popped into both cams to see, the one running 15fps CBR is showing just shy of 2 days or 48 hr recording available in the playback timeline, the other at 25fps approx 36 hours...
bigredfish
Known around here
So set that camera to 4096 bps - all other settings same - 15fps/Iframe 15 and really there isnt that much difference in this otherwise difficult low light scene... will see how it does in daytime....
4096 CBR (Change youtube setting to 1080p)
And here is same scene at 8192 CBR bitrate
4096 CBR (Change youtube setting to 1080p)
And here is same scene at 8192 CBR bitrate
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Shockwave199
Known around here
Holy crap though, the image quality looks much better at 8192.
bigredfish
Known around here
Yeah- I think so too. Its not just those two clips, I can see it in many dozens of clips I've downloaded in the past couple of months of tweeking and chasing the perfect image. I'm as far as I'm gonna get with that camera I think.
To be fair the white balance tends to shift at night in auto mode, sometimes better than others, but its a fair comparison to what I see in the difference with 2x bitrate.
To be fair the white balance tends to shift at night in auto mode, sometimes better than others, but its a fair comparison to what I see in the difference with 2x bitrate.
hmjgriffon
Known around here
I always run maxed out settings, if not, why did you buy a camera that could do them haha.
Is max always best given sufficient storage, cpu, etc.?
What I took away from some of the above info for example was that CBR with max bit rate but lower fps would = better image than with higher fps.
Or am I misunderstanding?
What I took away from some of the above info for example was that CBR with max bit rate but lower fps would = better image than with higher fps.
Or am I misunderstanding?
badboy
n3wb
Hello. I am new here but couldn't resist hopping on this band wagon. I ordered my SD49225T-HN from Andy and am loving it. One of the main uses was to interact with our dog who is having a little separation anxiety. I wanted to use the bi-directional audio to listen/talk to him.
I had read all the limitations of cctv audio (lack of full-duplex, should use VOIP instead, etc) but figured for the dog it would be okay. On the audio pigtails, I wired up the red to the speaker, the white to the microphone and tied all the grounds together. I used the Microseven M7WP microphone and a set of amazonbasics AC powered speakers.
Audio IN (mic) is awesome and I am very impressed with the Microseven. Audio out doesn't work at all as far as I can tell. I hooked some iphone earbuds up to the audio out and can't hear anything when I talk via BI or via the web interface on the camera. I tried hooking up a microphone preamp to the audio out line and still didn't get anything. I verified using an ohm meter that the output isn't shorted. This is my first run-in with audio out on an IP cam so any guidance would be appreciated.
Any idea what I am doing wrong? Do I need some sort of uber-low signal preamp? Has anyone else used audio out successfully on this beast or did I get a bum camera?
Oh yea, @dalepa I have the same issue as you in that I can't set a preset in BI by holding down on the preset button. I have to program presets via the camera's web interface.
For what it is worth my firmware version is "2.422.0000.0.R.4.2510, Build Date: 2016-09-21" and my PTZ Version is "3.02.20.RHNZ".
I had read all the limitations of cctv audio (lack of full-duplex, should use VOIP instead, etc) but figured for the dog it would be okay. On the audio pigtails, I wired up the red to the speaker, the white to the microphone and tied all the grounds together. I used the Microseven M7WP microphone and a set of amazonbasics AC powered speakers.
Audio IN (mic) is awesome and I am very impressed with the Microseven. Audio out doesn't work at all as far as I can tell. I hooked some iphone earbuds up to the audio out and can't hear anything when I talk via BI or via the web interface on the camera. I tried hooking up a microphone preamp to the audio out line and still didn't get anything. I verified using an ohm meter that the output isn't shorted. This is my first run-in with audio out on an IP cam so any guidance would be appreciated.
Any idea what I am doing wrong? Do I need some sort of uber-low signal preamp? Has anyone else used audio out successfully on this beast or did I get a bum camera?
Oh yea, @dalepa I have the same issue as you in that I can't set a preset in BI by holding down on the preset button. I have to program presets via the camera's web interface.
For what it is worth my firmware version is "2.422.0000.0.R.4.2510, Build Date: 2016-09-21" and my PTZ Version is "3.02.20.RHNZ".
Frank van der Heide
Pulling my weight
Is that really so?
But you gotta love the ability to draw the red square around object and the cam will zoom in on it perfect. Bi is still cumbersome when you want to zoom in on a object quickly. Also I always thought you had to set the preset in the camera first ?? My BI will not set a preset.
dalepa
Moderator
Zoom by squaring the subject using the mouse is a feature I would really like to see in BI. My Dahua SD29204T-GN 4x dome works fine with the BI zoom set along with my other PTZs. Guess we need some custom BI setting for the 25x
Yep, it is, because the bit rate is in kilobits per second, not kilobits per frame. If you have fewer frames in a second, there are more bits to use per frame for the compression, so each frame is compressed less, which means more detail is retained. That's all in theory though, in practice you may find that the difference is not discernable, or small enough that the higher framerate is worth the loss in detail. Increasing the I-Frame interval can also help retain details, and/or increase framerate (at the cost of a longer period of garbled video if there's packet loss).
To complicate things further, the bitrate required to retain a high degree of detail is going to be highly dependent on the image being recorded. E.g. the composition of colors and details and the amount of motion. So one camera's "best settings" could be awful in another camera. Fun isn't it?
wxman
Pulling my weight
Would be an improvement to have named presets on the live page...I can't remember what preset is what so I have to go to the PTZ setup menu when using presets...Then it's so easy to accidentally hit the "clear" button and all presets immediately deleted permanently. Happened to me once already. Still haven't found a way to back these up either. I've went through the whole "export settings" file and the presets are not included. If you lose them, you have to start over programming presets from scratch.
Shockwave199
Known around here
If anyone has the means to get a measurement of the inside diameter and outside diameter of the nose end of the wall mount for this camera it would be immensely appreciated. Also the length of the entire male part of the top of the camera itself- the part that inserts into the mount. The dahua spec sheet doesn't show it and what they do show is in metric and beyond what I understand, lol. I'm trying to get a real idea if this camera will fit into the mount I have for my current ptz. From what I can tell, it looks very close to maybe working out but I need real measurements. Thanks to anyone in advance.
wxman
Pulling my weight
Your images look really good! I don't know why mine won't look like that.
Also, unless those houses are kind of distant, then yours seems to have a much wider field of view than mine. Even on the widest zoom out, trees in the yard and such look unnaturally close/magnified.
Shockwave199
Known around here
I think according to the specs at widest it's 4.8mm which will seem a bit tight if your area is smallish. It's funny- the picture looks good but it's still has that 2mp look, lol. Starlight I'm sure rules in this camera and 25x zoom of course. Great price for this camera.