Is FPS constant across all inputs or varies with # cameras?

[tegatdavis 0]

I'm hoping you guys can help me out on this one. Let's take a sample DVR card with the following specs:

channels: 8

recording: 240 FPS

resolution: NTSC: 352x240, 640x480, 720x480

 

Is it safe to assume that the 240 FPS total (30 FPS each cam) is only possible when recording at 352x240? Now if I had 8 cameras and chose to record at 720x480 (4x 352x240) I assume then that that would give me 60 FPS total (240 / 4) for 7.5 FPS each cam? Now I'm not so sure about what happens when there is less than 8 cameras. If I were to only hook up 6 cameras and still recording at 720x480 would each cam get 10 FPS (60 FPS total / 6 cams) or will each cam be limited to 7.5 FPS? Also, can you specify different resolutions for different inputs?

 

BTW I'm trying to decide between the Geovision 1240 and the Avermedia NV6240EXP. Both have similar specs. The Avermedia is a bit cheaper but from what I've read on here it seems like Geovision's software is much easier to work with but both are good cards

[Soundy 1]

I'm hoping you guys can help me out on this one. Let's take a sample DVR card with the following specs:

channels: 8

recording: 240 FPS

resolution: NTSC: 352x240, 640x480, 720x480

 

Is it safe to assume that the 240 FPS total (30 FPS each cam) is only possible when recording at 352x240?

 

No - that will depend on the card. Some WILL record at full 240fps at D1 resolution.

 

Now if I had 8 cameras and chose to record at 720x480 (4x 352x240) I assume then that that would give me 60 FPS total (240 / 4) for 7.5 FPS each cam? Now I'm not so sure about what happens when there is less than 8 cameras. If I were to only hook up 6 cameras and still recording at 720x480 would each cam get 10 FPS (60 FPS total / 6 cams) or will each cam be limited to 7.5 FPS?

 

Again, all that will depend on the card and its specific design. Don't assume - check the card's specs and documentation. If they don't cover it, ask the manufacturer. If THEY can't answer it, run away from the thing and buy one with reliable support.

 

Also, can you specify different resolutions for different inputs?

 

That will depend partly on the card and partly on the software, but in most cases, you will be able to.

[shentim 0]

Hi tegatdavis,

 

I checked your inquiry with our engineer and his response is:

 

"Yes his math is correct.

The total number of FPS available will be divided by the number of channels recording.

 

So with 6 cameras recording at 720x480, it will be 60/6 = 10 fps per channel."

 

Feel free to contact our technical support department via live chat at usavisionsys dot com.

 

--

Tim Shen / Account Executive

USA Vision Systems, Inc.

[tegatdavis 0]

So I contacted Geovision live chat on their website and I got someone who wasn't very knowledgeable about the product at all. The person kept giving me generic answers to specific questions. On the other hand, Avermedia's live chat person was very knowledgeable. I know this is only one person but I've seen other people complain about Geo's customer support. Kinda makes you wonder if the problem is more systemic.

[shentim 0]

Hi tegatdavis,

 

Please let me know the technician's name and I will look in to the chat log for reference provided that the chat was done through www.usavisionsys.com.

 

I don't believe the problem is systemic, as a quick search through this site's forums shows very few issues where a client's issue was not resolved.

 

I will take note of this, I appreciate the feedback!

 

-Tim

[joelt 0]

I'm hoping you guys can help me out on this one. Let's take a sample DVR card with the following specs:

channels: 8

recording: 240 FPS

resolution: NTSC: 352x240, 640x480, 720x480

 

Is it safe to assume that the 240 FPS total (30 FPS each cam) is only possible when recording at 352x240?

 

No - that will depend on the card. Some WILL record at full 240fps at D1 resolution.

 

Now if I had 8 cameras and chose to record at 720x480 (4x 352x240) I assume then that that would give me 60 FPS total (240 / 4) for 7.5 FPS each cam? Now I'm not so sure about what happens when there is less than 8 cameras. If I were to only hook up 6 cameras and still recording at 720x480 would each cam get 10 FPS (60 FPS total / 6 cams) or will each cam be limited to 7.5 FPS?

 

Again, all that will depend on the card and its specific design. Don't assume - check the card's specs and documentation. If they don't cover it, ask the manufacturer. If THEY can't answer it, run away from the thing and buy one with reliable support.

 

Also, can you specify different resolutions for different inputs?

 

That will depend partly on the card and partly on the software, but in most cases, you will be able to.

 

- Soundy pretty much nailed it: a lot depends on the specific cards, manufacturers, or software capabilities. The best way to find out is call the manufacturer, or at least speak with a knowledgeable technician at your chosen vendor/lab.

 

We have DVRs that will allow you to adjust the resources being sent to certain channels, then we have some that do not allow that adjustment. Having 6 instead of 8 cameras hooked up to a system, like the example you described, shouldn't directly affect the performance, though, unless you actually change settings to focus resources on those 6 specific channels (if the hardware/software allows).

 

BTW I'm trying to decide between the Geovision 1240 and the Avermedia NV6240EXP. Both have similar specs. The Avermedia is a bit cheaper but from what I've read on here it seems like Geovision's software is much easier to work with but both are good cards

 

From feedback I have received, AVerMedia's software is "much easier to use than the Geo." Both are nice, I think there's just more of a learning curve with the GeoVision interface, settings, etc from an end-user's point of view. I doubt you would be disappointed with either card. Feel free to PM me if you'd like to get in touch with some of our techs that could give you some more pros/cons and explain it a little better than I.

 

- Jason