B54IR-Z4E Low Quality With Vehicle Motion

Ny2ca

n3wb
Jul 9, 2024
3
0
Ca
I recently set up a pair of B54IR-Z4Es for LPR duty. On one of them, when a vehicle moves through the frame during the day, the picture becomes blocky and pixelated and loses definition but then recovers. At night, the image remains clear and the plate is easily readable and I don't notice the issue when people walk by during the day. For encoding I'm using H.264, 15 FPS, CBR 8192. Exposure settings are Manual, 1/2000, Gain 0-30 and NR 25. I've included screenshots of the issue below as the vehicle progresses through the frame and all settings. Any tips or ideas on how to resolve this issue?


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I increased it from 20MB to 40MB and I'm still seeing the issue. On some cars I'm seeing some artifact behind them as they drive through. My neighbor drove by much slower pulling into their driveway and it was clear throughout for that clip.
 

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You're really not zoomed enough for reliable LPR IMHO, but that said, on the blurry trail of artifacts behind the vehicles, I've posted about this many times.

It's common with the Z12 and Z4, might be with regular Z too I haven't tried.
But it's a trail of artifacts on faster reflective targets while using fast shutter.
At night it presents as "tiger stripes". Hard to see if you're running 1/1000 - 1/2000 but like the daytime, it doesn't effect the actual target

The more zoomed you are the more its visible.

The good news is it doesn't seem to actually effect the target itself, but trails behind it

I haven't found a way to get rid of it, its the optics/sensor and its present on the 4KX and 4KT as well. Worse on those


Control images
HOA Entr_EntTag_main_20220807115424_@3.jpg live2.jpg


Examples
HOA Entr_EntTag_main_20220806171340_@3.jpg HOA Entr_EntTag_main_20220807115430_@3.jpg HOA Entr_EntTag_main_20220807121531_@3.jpg HOA Entr_EntTag_main_20220807131007_@3.jpg

Very visible here
View attachment HOA Entr_ch3_20220807143207_20220807143221.mp4
 
Try upping the bitrate to 12000 and see if that helps it.
That seemed to solve the problem. Thank you!

You're really not zoomed enough for reliable LPR IMHO, but that said, on the blurry trail of artifacts behind the vehicles, I've posted about this many times.

It's common with the Z12 and Z4, might be with regular Z too I haven't tried.
But it's a trail of artifacts on faster reflective targets while using fast shutter.
At night it presents as "tiger stripes". Hard to see if you're running 1/1000 - 1/2000 but like the daytime, it doesn't effect the actual target

The more zoomed you are the more its visible.

The good news is it doesn't seem to actually effect the target itself, but trails behind it

I haven't found a way to get rid of it, its the optics/sensor and its present on the 4KX and 4KT as well. Worse on those


Control images
View attachment 223284 View attachment 223286


Examples
View attachment 223287 View attachment 223288 View attachment 223289 View attachment 223290

Very visible here
View attachment 223291
I was wondering about that. I'm maxed out on the Z4 but I do have a Z12 I could throw up there instead to get more zoom on the plates and get rid of the driveway that's just taking up space in the image.

That's interesting on the artifacts. Upping the bit rate helped reduce it from large blocks to similar to what's visible in your examples.
 
Those are compression artifacts.. 2 seconds video stream consists from 1 full I-frame which contains full sharp image which recovers image and (49/59) delta frames which have only changes compressed into small bandwidth. THis is way image recovers every 2 seconds (with default frame rate and I-frame parameters)...

Solutions for Your problem:
  • you can increase bandwith,
  • you can manipulate I-frame,
  • you can change Smooth stream settings - it changes how much bandwith is allocates into I-frame vs delta-frames... Move lower into around 20-30 on Smooth side (this is for classic CBR fanatics), this should give more bandwidth for delta-frames...
  • you can change Encoding strategy to AI Codec (not SmartCodec). it's new much more advanced algorithms which based on AI information (moving human/vehicle) allocates dynamic way bandwith for I-Frame and delta-frames and increase quality around moving objects... Depending of camera model and firmware version it have 3 sub algorithms (CBR, ABR, VBR) - you can try CBR and VBR...