Why doesn't a screen grab work when playing a DVD? [Archive] - Glock Talk

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Blaster
02-15-2011, 18:18
The other day I was watching a DVD on my computer and i thought it would be neat to pause the DVD, Print Screen, Paste into Paint and make it a Wallpaper.

It did not work I just got a dark screen in Paint. Then I remembered that I had tried this a while ago with the same result.

Can anyone explain why I was unable to get a screen grab from a DVD and if there is a way to do it?

HerrGlock
02-15-2011, 19:59
You have to use the DVD player's software to take a screen grab.

It has to do with copyright stuff, is why they did it this way.

The DVD players are actually running a virtual machine so nothing is being rendered by your OS other than that black box overlaid with the DVD player software.

Yeah, that's really simplistic but it's close enough. You cannot take a pic via print screen. On just about every DVD player's menu and/or icon bar there's a "save screenshot" option, use that rather than print screen.

Blaster
02-15-2011, 21:09
On just about every DVD player's menu and/or icon bar there's a "save screenshot" option, use that rather than print screen.

Unfortunately not mine. I am running Cyberlink Power DVD DX on a Dell laptop.

Thanks for the info. I figured it must have something to do with copyright issues.

Angry Fist
02-15-2011, 21:14
Use VLC Media Player. It's free. Does Capture.

www.videolan.org (http://www.videolan.org)

JimmyN
02-16-2011, 05:35
Can anyone explain why I was unable to get a screen grab from a DVD and if there is a way to do it?

You have to turn off hardware acceleration, then you'll probably be able to capture the screen shot and you won't get that black, or pink, image. The video overlay hardware acceleration uses a "colorkey" technique to replace a specific pixel color (usually black) with the video. Anywhere a "colorkey" pixel appears it will be replaced by a video pixel from the encoder. But this happens downstream from video memory, so if you do a system "print screen" it's taken from video memory before the overlay occurs and all you get is a screen shot of the "colorkey" black or pink pixels. Turning off hardware acceleration forces the encoder to write to standard video memory so your PC's print screen function will work.

Most DVD and video players for PC's have a screen capture option, if you use that rather than using the systems 'PrntScrn" function it will take care of that problem automatically.

But not in all cases, sometimes you'll still need to turn off hardware acceleration to make a capture. For example PowerDVD playing a Blu-Ray disk will not take screen captures, that function is grayed out, because hardware acceleration is turned on and you can't turn it off while playing Blu-Ray. So you can't get a screen capture using "PrtScrn" or PowerDVD's capture option.

But instead of playing "the disk" in the normal fashion you open PowerDVD, then select "media files" as the source and navigate to the Blu-Ray disk. Double click on the movies .m2ts file to play it, turn off hardware acceleration, and then the capture option will appear and you can do HD screen captures right from PowerDVD.

BuckyP
02-16-2011, 08:04
Unfortunately not mine. I am running Cyberlink Power DVD DX on a Dell laptop.

Thanks for the info. I figured it must have something to do with copyright issues.

I use Power DVD and there is a screen capture, though it's very hard to find. If you look in the Display window, right underneath the Title, there is a picture of a camera. If you mouse over that, the tool tip pops up "Capture Frame". Use that to capture a screen shot.