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Olympia Brackin

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Aug 2, 2024, 9:23:16 PM8/2/24

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Since all the DVRs we carry now have VGA output, I would like to find a way of taking screenshots from a VGA signal, if possible without doing VGA to video conversion, and then capturing like we are doing now. Most DVRs will have no more than 1024x768 or 1280x1024 resolution, and converting it and capturing it at 704x576 or pointing a camera at a computer monitor do not seem good ways for taking screenshots.

I have seen come VGA capture devices, but they are mainly for doing video capture and they are not what I would call cheap; this one is about US$300, a bit too much for just taking a few screenshots now and then: -grabbers/vga2usb/

The logic behind this move is that it shows us the full main monitor out, at a fair resolution, and as long as we use a short, high quality cable, the image at the encoder will look pretty good (and it does!). And since we are not creating "full screen" video, but rather something that is viewed on youtube, then 704 x 480 is fine.

Can it be done with the BNC output, or with VGA to video converter? Sure, but the quality won't be so good... I have been doing it this way for years just for taking small screenshots for ouw web site (640x480).

I got to thinking if you just wanted to show a screen shot of certain menu functions and such, you could always loop out the main out to channel 1 on your DVR, go onto your remote viewing software and capture the images that way as well. I did this and I got a nice clear D1 image. Of course this wont work if you are trying to show a screen shot of all 8 channels being displayed on the screen. And you will want to make sure to turn off your time stamp and channel display.

I just had another idea as well: Loop the main out into one of the DVR channels, set that channel to the highest resolution/fps/qual, then go through all the steps that you want to record and export that video. This would work especially well if your DVR or CMS can export an AVI.

The only problem I have encountered with that is if your DVR cant do 30 FPS per channel at D1 then it looks kind of funky when you are trying to show a video of how to get through certain parts of the menu. That is why we just do screen shots when it comes to showing examples of the main menu.

I have to agree with that... And a screenshot of maybe 1024x768 resolution captured converted to analog at 704x576 (PAL, NTSC it would be a bit different) just doesn't make justice. See rory's screenshot above or the following (resized/croped to make it smaller than 150Kb). Small text also can become very difficult to read.

Guess if I want to capture VGA at 1024x768 or 1280x1024, I will just have to pay for a good VGA capture device like the one on my first post. I would have anyway with screenshots, not that I really need video capture, but I doubt I can find something that would just take screenshots from a VGA output.

Keep in mind that the highest resolution you will get doing the loop through method is D1. Usually this is enough to show examples of screen shots of the menu. Here is an example of one we took using this method (we cropped it a little to take out the channel display at the top left):

On some DVR's, even if you do connect your DVR to a computer monitor via VGA, the menu screens are still D1 resolution, even though they are on a 1024x768 rez monitor, its just a D1 image expanded to fit the high resolution monitor. Of course there are some exceptions, one is a Dahua DVR that we just received in. It appears that they made their menu screens Hi-Def. It had HDMI, BNC out, and VGA out. So I hooked all three outputs to an LCD TV we had here and connected it to the RCA, VGA, and HDMI input and switched between inputs. THe menu screens on the VGA and HDMI (which looked the same) was significantly better than the RCA. Anytime I increased the resolution on the DVR, the menu screens got better. However, and this probably goes without saying, the video looked exactly the same on all three inputs, you will never get better than D1 video on a CCTV DVR so there is really no advantage to using a VGA, or HDMI with that.