How is this black and white line on top of the picture called?

[flashandpan007]

How is this black and white line on top of the picture called?
Why is it there? I've heard of teletext, but I also have bought some DVDs in the past which also have some of this black white line on top of the picture and there is no teletext.

[newpball]

According to many it is considered normal and that you should use overscan to solve it!

[smrpix]

In that location, probably vertical interval timecode (though it should be a few lines higher.) May be Macrovision.

[jagabo]

It's "line 21" (NTSC) or "line 25" (PAL) closed captions.
http://en.wikipedia.org/wiki/EIA-608
http://en.wikipedia.org/wiki/Closed_captioning

[pandy]

This is WSS signal and this is line 23 in PAL (first half of line 23) - http://www.etsi.org/deliver/etsi_en/300200_300299/300294/01.04.01_60/en_300294v010401p.pdf

One of main functions is AFD http://en.wikipedia.org/wiki/Active_Format_Description and (my opinion) why it is not masked (WSS occupy normally not visible half line of the first visible video line).

TXT lines are on VBI area and they are not visible at all, usually they occupy more than few video lines (in fact they can start from line 6 till line 22).
Usually TV should have function to mask first half/whole line 23 to avoid visibility of WSS.

It's "line 21" (NTSC) or "line 25" (PAL) closed captions.
http://en.wikipedia.org/wiki/EIA-608
http://en.wikipedia.org/wiki/Closed_captioning

PAL have no CC similar to USA (NTSC) - for subtitling TXT system (usually WST) is used, line 25 in PAL will be third (2.5) visible line so for sure it will be not used for any data service.

[LigH.de]

The Widescreen Signaling should not have been encoded. It is supposed to be in a vertical blanking gap.

Diagram in a German article about "exotic interlacing": The first half of the top line in the second field should not be drawn by a CRT monitor. (English translation by StainlessS)

[pandy]

The Widescreen Signaling should not have been encoded. It is supposed to be in a vertical blanking gap.

Diagram in a German article about "exotic interlacing": The first half of the top line in the second field should not be drawn by a CRT monitor. (English translation by StainlessS)

In digital video first half of the line 23 (i.e.place where WSS is transmit) is stored as normal video area (and as such some standards e.g. NORDIC require from digital decoder to mask line 23).
In normal cases (when overscan is applied) this line not visible - it is only visible in analog TV with analog 16:9 mode on 4:3 screen + on digital TV where non overscan mode is used.

my side comment - usually digital encoders (but this mean digital analog signal composite/component form) can't satisfy requirement to half line - usually one of fields is longer by one line (average gives two half lines).