Capture analogue with 720x576 has tiny horizontal bar at bottom

[ManUtdFans]

I tried to capture using external USB capture device for my analogue Sony video 8 tapes to my pc using Ulead Video Studio 10 and Cyberlink Power Producer, both produced output video files have a tiny horizontal bar about 5mm height at the bottom of the video when I set the capture resolution at 720x576.
There is no such tiny bar at the bottom when I set to 720x480.

Any idea?

[themaster1]

i record from a setop box i got the same thing i think it's normal it's a scale bar. Unless you crop while you record you can't remove that i'm affraid

[JohnnyMalaria]

It's probably the head switching noise which is present on VHS, S-VHS, Video8, Hi8 etc. This is due to the way that a rotating drum with two heads is used. As one head scans the tape, the other swings away from the tape. Hence, the signal switches to-and-fro between each head.

It is usually invisible on a TV because the TV deliberately overscans the video image by a few percent. On a computer, you see the whole frame - warts and all.

If you intend to distribute the video on-line or watch it on a PC, you will want to crop it (or just replace with a black bar). If you intend to view the editing video on a TV (e.g., as a DVD), you can leave it as it is since a TV won't show it.

[2Bdecided]

In Australia, a PAL country, do not use 720x480!

[jagabo]

If you're going to make a DVD mask the noise with an 8 pixel high black bar. That way you won't waste bitrate encoding the noise.

[JohnnyMalaria]

Good point

[ManUtdFans]

Hi Johny,

What do you mean it won't appear on TV?

I noticed the tiny bar appears both when I was capturing the video from my SONY camcorder and when I replay the AVI file from VideoLAN VCL Media Player.

And can you tell me why:
"In Australia, a PAL country, do not use 720x480! "

[jagabo]

What do you mean it won't appear on TV?

Because TVs overscan the image. They draw a picture that's larger than the visible part of the screen so you don't see the outer edges of the picture. This is done to hide linearity, sizing, and centering problems -- and noise at the edges of the frame.

And can you tell me why:
"In Australia, a PAL country, do not use 720x480! "

Because PAL uses 576 scan lines. If you only captured 480 scan lines (NTSC standard) you would be missing 20 percent of the picture.

[ManUtdFans]

What do you mean it won't appear on TV?

Because TVs overscan the image. They draw a picture that's larger than the visible part of the screen so you don't see the outer edges of the picture. This is done to hide linearity, sizing, and centering problems -- and noise at the edges of the frame.

If I capture the video-8 from my old camcorder in 720x576 and finally burn in DVD, the TV will NOT show the bottom 5mm tiny bar when the DVD is played in DVD player?

And can you tell me why:
"In Australia, a PAL country, do not use 720x480! "

Because PAL uses 576 scan lines. If you only captured 480 scan lines (NTSC standard) you would be missing 20 percent of the picture.

Thanks

[ManUtdFans]

If I capture the video-8 from my old camcorder in 720x576 and finally burn in DVD, the TV will NOT show the bottom 5mm tiny bar when the DVD is playing in DVD player?

[2Bdecided]

That's right.

[jagabo]

Some of the newer HDTVs have the option to show the entire frame (no overscan). In that case you will see the noise at the bottom of the frame.

[ManUtdFans]

Hi,

I just have no idea why the TV will not show the bottom 5 mm bar.
There are so many sizes/resolutions of plasma/LCD TV in the market, they are all capable to 'disappear' the bar?

[jagabo]

I just have no idea why the TV will not show the bottom 5 mm bar.

It's the way TVs are designed -- intentionally.

There are so many sizes/resolutions of plasma/LCD TV in the market, they are all capable to 'disappear' the bar?

Yes. All of them.

[edDV]

Read here for the background.
http://en.wikipedia.org/wiki/Overscan

They overscan the TV so that you don't call them to complain about trash at the bottom of the screen, codes at the top of the screen or blanking showing on the left or right. They are sick of those calls.

BTW, most TV sets don't overscan the VGA (Computer/Game port) so that menus can be seen out to the edge.

[dadrab]

BTW, most TV sets don't overscan the VGA (Computer/Game port) so that menus can be seen out to the edge.

I swear...everytime I come to this site, I learn something. 8)