Anyone know anything about the ROI tab? REGION OF INTEREST

Murphy625

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Been playing with the camera now for a week and just got around to figuring out the ROI tab. I'm a bit confused. Its called the "Region Of Interest" and is supposedly forces more detail in the video in the area you select. This doesn't make any sense because why wouldn't someone just select the entire frame to improve the performance of the camera?

So to get more detail in the area you select, what am I giving up? There's got to be a trade off somewhere..

I put Blue Iris on manual record and activated the ROI function.. then went back to see what it did.. and the picture does change a bit.. like it sharpens up or something.
 

LT20

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I have been experimenting with ROI and bandwidth. I read somewhere on here that on Dahua cameras, selecting the whole frame for an ROI would enable the camera to go above the maximum bandwidth allocated. I have confirmed that it also works on my LTS (hikvision generic) cameras. I'm still trying to dial in a good blend of image quality and storage space. Previously on my NVR I was running H265+ for storage capacity, but now that I'm running a pc with Blue Iris, I'm running H.264 for hardware acceleration etc. I've heard the phrase before - "It's not what you expect, it's what you inspect". I was under the assumption that using VBR and allocating 16384, I ought to be using approximately half of that. Well it turns out that because I was running the highest quality setting, even with negligible motion, I was often sitting at the max limit. I currently have some of my cameras down to "low" or "lower", and some using ROI. I had Blue Iris recording hour long files, so that I could easily figure the average bandwidth per camera with my current day and night settings. I think I will have enough time this week to drop the files to shorter durations so that I can look at MAX / MINs for file size and determine if I have allocated enough quality.
 

tigerwillow1

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I've used ROI on both Hikvision and Dahua cameras. It really makes a difference in the selected image area, while degrading the area outside of the ROI. I agree that the way it works is illogical. I initially thought that if you ran a camera at its maximum BPS rate, ROI would be irrelevant. Since ROI can improve the image even then, it means that the maximum capability of the image sensor isn't being used, which leads me to ask why not? When you for instance get a 4 MP camera to replace a 2 MP camera, you have to run a higher bit rate to see the higher resolution details. So why not allow the 2 MP camera to run a higher bit rate to get a better image from its sensor? I can only think it's one of those business decisions that doesn't make sense to me.
 
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