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I have seen a few posts refer to "4K". Such as "in 4 years all equipment will be 4K". What is 4K.

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4K is also known as Ultra HD or 2160p. Equals 3840x2160 pixels or 8.3megapixels.

 

8K Ultra HD/Super Hi-Vision (4320p) also exists (at least on televisions). Equals 7680x4320 pixels or 33.2 megapixels.

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More common is 2K or twice 1080P or half 4K also known as 1440P. You can buy 2K monitors for $600ish where 4K monitors are in the thousands.

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4K is a broadcast standard. 4K = 3840x2160 at a minimum of 24 FPS. If it can't do 24 FPS it's technically just an 8.3 megapixel camera.

 

4K is more meaningful when discussing monitors or TVs since very few surveillance systems need a 8.3MP camera streaming at 24 FPS.

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4K is a broadcast standard. 4K = 3840x2160 at a minimum of 24 FPS. If it can't do 24 FPS it's technically just an 8.3 megapixel camera.

 

4K is more meaningful when discussing monitors or TVs since very few surveillance systems need a 8.3MP camera streaming at 24 FPS.

 

cbodby is 100% correct!

 

Many companies were showing 4K resolution cameras at ISC but few of them where 30FPS.

 

Here is a sample from Axis's new 4K camera

 

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Personally I think H.265 is gonna be needed for 4k recording. Rumour has it that it can use up to 50% less storage space due to better compression. How true this is I'm not sure but still pretty excited....

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H.265 will play an important role in the adoption of resolutions of 4K+

 

That being said, I wouldn't get too excited. I had a very frank conversation with Axis at ISC and they indicated that we should not expect to see H.265 in the video surveillance industry till at least 2016. Also, while H.265 could reduce file sizes by up to 50% (of H.264), realistically it will be more like 25%.

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I was kind of surprised at the bandwidth from the 4K cameras that we saw at ISC. Bosch had there camera setting and streaming live at the show and they were showing around 8Mbps. Axis was claiming they needed a minimum of 10Mbps.

 

If you think about it 4K is 4 times the resolution then 1080P so if you have 4Mbps from a 1080P camera then you would be around 16Mbps for a 4K camera.

 

Bandwidth isn't as big as a concern as CPU/GPU processing power on client machines. How many 4K streams can today's clients simultaneously decode at once is the big question.

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Bandwidth isn't as big as a concern as CPU/GPU processing power on client machines. How many 4K streams can today's clients simultaneously decode at once is the big question.

 

So the need for double and triple stream cameras. I do not even have a 4k display, so I would not even have the need to decode one single 4K stream, not to say several of them... But a secondary stream of 1080p, and even a third stream for mobile viewing would be nice.

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I do not even have a 4k display, so I would not even have the need to decode one single 4K stream, not to say several of them... But a secondary stream of 1080p, and even a third stream for mobile viewing would be nice.

 

You still need to decode the stream. Your monitor won't change that.

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I do not even have a 4k display, so I would not even have the need to decode one single 4K stream, not to say several of them... But a secondary stream of 1080p, and even a third stream for mobile viewing would be nice.

 

You still need to decode the stream. Your monitor won't change that.

 

Of course you do, that's why I would rather use a 1080p secondary stream, than 4K main stream.

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I do not even have a 4k display, so I would not even have the need to decode one single 4K stream, not to say several of them... But a secondary stream of 1080p, and even a third stream for mobile viewing would be nice.

 

You still need to decode the stream. Your monitor won't change that.

 

Of course you do, that's why I would rather use a 1080p secondary stream, than 4K main stream.

 

At some point you're going to want to watch the recorded 4K stream or digitally zoom the live view in which case you will need to decode the 4K stream.

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According to Axis Press release about the 4K camera, you can only view 1080p from the camera and only take advantage of the full 4K resolution when zooming etc, i would like to know if this is really the case, does it only stream 1080p thru RTSP, and when you for example zoom in (with some "virtual PTZ zoom" axis uses on some models) it still streams higher resolution/quality image?

 

“To manage bandwidth consumption, users can view the live video stream in HD 1080p and take advantage of 4K recordings for forensic purposes. “

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A camera that is labelled 4K ought to be able to deliver a full 4K live stream too.

 

"Initially, it is likely that most customers will be using a standard HDTV monitor. 4K makes it possible to enhance any portion of the screen without losing details. To manage bandwidth consumption, users can view the live video stream in HD 1080p and take advantage of 4K recordings for forensic purposes. “

 

I think they are trying to deal with the idea that a 4K stream is "wasted" on a 1080p screen. Naturally, when you are looking at the full FOV, you might say that 75% of the pixels sent across are not seen, and therefore "wasted". But if you digitally zoom into the live feed, you can zoom 4x before you see ANY pixelation on a 1080p screen - assuming that you are using the entire screen for the video feed. If you are showing the video in a smaller window (most likely you are), you can zoom in even further before pixelation occur.

 

Keep in mind that if bandwidth is an issue, then - having a 4K go to the NVR, while opening a secondary 1080p stream to a client will obviously INCREASE total bandwidth output from the camera, while on the other hand, lowering the bandwidth from the NVR to the client. Another option is to do server side transcoding (to go from 4K to 1080p for example), but that is VERY CPU (or GPU if you like) intensive.

 

4K is going to require some pretty beefy client machines if you want to see more than a few cameras on screen at once, OR a whole lotta bandwidth.

 

(why do people call it 4K UHD? isn't UHD redundant?)

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4K UHD is like advertisements that say 1080P HD.

 

It will use a whole bunch of CPU to decode 4K from multiple cameras. Don't know what other NVR software does, but Milestone has a feature where you can select the sub-stream for live viewing, but still records and play's back at full resolution. Then the client app doesn't have to worry about 4K. To me, the high resolution is valuable for playback to get details. When live viewing say even 4 cameras, you don't need all 4 to be 4K on a 4K monitor.

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how the CPU bear, as it is 4 time 1080P. due to the brandwith and data transfering, offen hanging up in playing back for the HD-SDI 1080P DVR.

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