Tuesday, July 9, 2013

Pristine Quality Screenshots with Hauppauge HD-PVR

The Hauppauge HD-PVR is perhaps one of the most well known HD capture devices on the market, and is actually the first HD capture device to include H.264 hardware encoding. This hardware allows the unit to seamlessly encode to H.264 on the fly without any impact on the CPU performance of the  computer.

While this is great for videos, it's an absolute nightmare for taking screenshots. This is mainly due to the automatic H.264 compression which cannot be cancelled into uncompressed, and lower maximum 13.5Mbps bitrate limit. Most of the time, attempting to capture a scene featuring heavy motion, then pulling a certain frame out of that clip to use as a screenshot will result in an image that is full of compressed artifacts. It doesn't help either that the HD-PVR—or at least the original model—didn't have any way to directly capture screenshots.

Here is an example of exactly what I'm talking about: capturing a video, then opening it in an viewer/editor and taking a frame from somewhere and making that frame into a screenshot. Note the compressing artifacts.

Wrong way to create a screenshot with HD-PVR.
There is a secret to being able to capture pristine, excellent quality screenshots on any certain part of any scene with any motion, however. And while this tactic works as intended, it does require some extra work, particularly good timing and a little luck.

The secret is really simple actually, just recall this—the first frame (frame 1) of any video the HD-PVR captures will always be in clean, pristine quality with no compression artifacts, no matter where it is taken. Although it's not as perfect as an uncompressed frame, it still comes very close.

So instead of trying to pull a frame out from the midst of a video, capture the frame you want as soon as it appears on the screen, quickly stop the capture, open up the mp4 or ts file—with something like DGAVCIndex—and just copy the first frame to be the screenshot. If you fail to get the right frame as frame 1, just simply keep trying until you get the frame you want, or closely to the frame you want.

Tip: If the time the device takes to start capturing a video takes too long, try capturing a scrap video first. Doing so will cause the HD-PVR to capture nearly instantly on the next and subsequent captures. To avoid lags and stuttering from high CPU usage, you can in conjunction toss the entire Total Media software altogether and resort to command prompt capturing using rcTVCap.

The right but more difficult way.
 Walla! All compression artifacts are gone and we have a very lovely screenshot to share!

This method may also work for other capture devices that can only capture in a compressed format. This may additionally be invaluable to those who own the HD-PVR 2, as it now has a built-in take screenshot tool. Nevertheless, I'm not sure how that function works on that model, so if your screenshots are looking too pixelated and nasty, it doesn't hurt to try this out.

2 comments:

  1. Is that Sophitia face sitting the Apprentice? Yummy!

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  2. I knew it! The only possible way is to capture frames from video....

    ReplyDelete