Correcting overscan in captured MPEG2 video

[lchiu7]

Up till now I have been capturing video in MJPEG (PicVideo codec) format using a WinTV PCI card or FlyPV Platinum card. I use Virtualdub to remove the ads, apply the smart resize filter to resize the video to correct for overscan issues and then either frameserve to tempgenc or mainconcept to convert to MPEG2 format before authoring to DVD.

I found if I didn't resize the captured video before authoring to DVD, the resultant picture had pretty noticeable overscan issues on all my TVs.

That works pretty well and I have the process down pat now. But it does take time. For each hour of video I have to add another hour for the MPEG2 conversion.

I have just purchased a Hauppauge PVR250 card. Now the capture is directly to MPEG2. I can use Womble or whatever to remove the ads but I have no idea how to resize the video now without reencoding it in say tempgenc which is a waste of time given it's already MPEG2 compliant video

I looked at Virtualdubmod but while it can open the MPEG2 file and I can apply the resize filter, it won't output MPEG2 - it outputs AVI which then has to be encoded again. Videoredo, a program that seems to have good ratings also cannot resize video

Anybody have any ideas on how to do this? What are folks doing about the shows they record using a PVR250 and authoring to DVD? Is overscan not an issue?

Thanks

Larry

[TBoneit]

Is overscan an issue? that depends on the viewer.

All normal TVs overscan. There is data at the top of the screen that you wouldn't want to see. VHS Tapes also have stuff at the bottom you wouldn't want to see. Normal made for TV videos are designed to have all the action in the safe area ands the overscan area usually contains nothing important.

If overscan bothers you than you are in for encoding any video captured even with the new hardware. Unless you can set it to capture with borders around the capture they'll need to be encoded.

One work around is to see if your TV set has service controls that will let you reduce the overscan area. On the really old ones that had tubes and Horizontal and vertical size settings on teh back it was a snap. On newer ones you need to have a service menu that allows size adjustment.

Another problem is that if you encode the MPEG2 captures you will be losing quality. The card you have is for those who don't want to take the time to encode and want it ready to author. For your MPEG2 streams I'd just edit out commercials and start end overruns with VideReDo and then author.

The other problem with what you have been doing is when you have to replace a TV set your new one may have less overscan and now you will have black borders.

Good Luck

[reboot]

I'm interested in this too! (Only had my PVR-250 a few days).
Edit: posted late.
New question...
If the PVR captures the whole picture, then the overscan, once burned to disk and played, would be the same as the original.
If the PVR takes into consideration the overscan, then once burned and watching on TV, there would be double the amount of stuff lost to overscan, no?
(I hope that makes sense)

[gshelley61]

Yes, definitely avoid cropping or resizing MPEG2 video because you will have to re-encode... with a noticeable loss of quality.

[FulciLives]

I'm interested in this too! (Only had my PVR-250 a few days).
Edit: posted late.
New question...
If the PVR captures the whole picture, then the overscan, once burned to disk and played, would be the same as the original.
If the PVR takes into consideration the overscan, then once burned and watching on TV, there would be double the amount of stuff lost to overscan, no?
(I hope that makes sense)

The capture will look the same on the TV once you burn it to a DVD.

It doesn't look smaller or bigger.

- John "FulciLives" Coleman

[lchiu7]

I'm interested in this too! (Only had my PVR-250 a few days).
Edit: posted late.
New question...
If the PVR captures the whole picture, then the overscan, once burned to disk and played, would be the same as the original.
If the PVR takes into consideration the overscan, then once burned and watching on TV, there would be double the amount of stuff lost to overscan, no?
(I hope that makes sense)

The capture will look the same on the TV once you burn it to a DVD.

It doesn't look smaller or bigger.

- John "FulciLives" Coleman

That's interesting. When I capture using the FlyTV Platinum card using iuvcr and the Picvideo codec (768x576 PAL) and just convert to MPEG2 and burn to DVD the output picture shows major overscan issues on my TVs. This is why I have to resize before converting to MPEG2

Should I be capturing at a different size? IUVCR also offers 720x576 or 704x576 but no choice on the vertical size

Larry

[FulciLives]

The overscan of the copy is the same as the original. There is no difference.

Take a source like a VHS tape and capture then burn to DVD keeping the resolution Full D1

Then watch the DVD and the original VHS on a TV and flip back and forth with the input switch and it should look the same in terms of "overscan".

- John "FulciLives" Coleman

[reboot]

So the PVR-250 is capturing the WHOLE thing? This would explain the "noise" at the bottom of VHS caps, that isn't visible once burned because it's in the overscan area. (the bulb is getting a little brighter).

[lchiu7]

The overscan of the copy is the same as the original. There is no difference.

Take a source like a VHS tape and capture then burn to DVD keeping the resolution Full D1

Then watch the DVD and the original VHS on a TV and flip back and forth with the input switch and it should look the same in terms of "overscan".

- John "FulciLives" Coleman

I will give that a try. The overscan I am experiencing is recording TV. If I record TV at 768x576 and then author that to DVD only doing MPEG2 conversion and comparing the DVD video with the TV picture, the DVD video is "larger" - that is it seems that the DVD image has enlarged for some reason so image gets truncated at the top and sides. Could this be because I am recording at an AR higher than broadcast so my capture is being enlarged during capture?

Larry

[Soopafresh]

Does the following constitute Overscan ? Note the top of the image, and also the green stripe on the right side. Not trying to jack this thread, just want to understand the term.

[TBoneit]

The overscan of the copy is the same as the original. There is no difference.

Take a source like a VHS tape and capture then burn to DVD keeping the resolution Full D1

Then watch the DVD and the original VHS on a TV and flip back and forth with the input switch and it should look the same in terms of "overscan".

- John "FulciLives" Coleman

I will give that a try. The overscan I am experiencing is recording TV. If I record TV at 768x576 and then author that to DVD only doing MPEG2 conversion and comparing the DVD video with the TV picture, the DVD video is "larger" - that is it seems that the DVD image has enlarged for some reason so image gets truncated at the top and sides. Could this be because I am recording at an AR higher than broadcast so my capture is being enlarged during capture?

Larry

One question is why are you capturing at that resoluion instead of PAL standard of 720 by 576? Or NTSC of 720 by 480 if in NTSC land?

Cheers

[gshelley61]

"Overscan" is what televisions do. On your computer monitor, you can see the entire frame, edge to edge, top to bottom. There are frequently undesirable things that occur around the edges of the frame... for example, VHS has a bunch of smearing artifacts that are at the lower edge of the frame - which is totally normal. Your television overscans the frame by 4-7 percent so you never see that kind of stuff.

[lchiu7]

The overscan of the copy is the same as the original. There is no difference.

Take a source like a VHS tape and capture then burn to DVD keeping the resolution Full D1

Then watch the DVD and the original VHS on a TV and flip back and forth with the input switch and it should look the same in terms of "overscan".

- John "FulciLives" Coleman

...
Larry

One question is why are you capturing at that resoluion instead of PAL standard of 720 by 576? Or NTSC of 720 by 480 if in NTSC land?

Cheers

Good question. It was a default setting in iuvcr. I changed it to 704x576 and did a test. The authored DVD played the same as the original picture! Guess I just hadn't realised I had the wrong capture setting. That makes life much easier

Larry

[ronnylov]

The overscan of the copy is the same as the original. There is no difference.

Take a source like a VHS tape and capture then burn to DVD keeping the resolution Full D1

Then watch the DVD and the original VHS on a TV and flip back and forth with the input switch and it should look the same in terms of "overscan".

- John "FulciLives" Coleman

...
Larry

One question is why are you capturing at that resoluion instead of PAL standard of 720 by 576? Or NTSC of 720 by 480 if in NTSC land?

Cheers

Good question. It was a default setting in iuvcr. I changed it to 704x576 and did a test. The authored DVD played the same as the original picture! Guess I just hadn't realised I had the wrong capture setting. That makes life much easier

Larry

Some capturing cards have more correct aspect ratio at 704x576 than 720x576. So in this case when you captured 768x576 you could have resized it to 704x576 instead of 720x576 or just capture 704x576 directly as you found out.