SVideo -> heavy noise

[MarcN]

Hello
I'm using a FlyVideo3000 Card (SAA7134 Chip) to capture video from an analogue satellite receiver (my VCR produces the same results). The card has a Composite-In (FBAS) and a SVideo-In (SVHS). The picture I get from the Composite-In is slightly blurred but otherwise fine. The SVideo-In however produces heavy noise in the picture. See below:

Composite:
http://home.arcor.de/marcn_de/composite.png

SVideo:
http://home.arcor.de/marcn_de/svideo.png

(You may have to enlarge the pictures)

The satellite receiver has only SCART-Outputs so I have to use an adapter. I opened one of them and this is what I found:

SCART-Pin #15 (SVHS Chroma according the receivers manual) is connected to the SVideo-Out of the adapter.

SCART-Pin #19 (Video-Out) is connected to the Composite-Out AND the SVideo-Out of the adapter.

So the complete Composite-Signal seems to be used as the Luma-part of the SVideo-Signal. Is this ok or could it be the source of the noise?

Thanks!

[Arachnotron]

The adapter is correct. There are several ways to wire up a SCART, and the composite video out pin is indeed the same as the luma pin for s-video.

You probably need to switch the receiver to s-vid mode in some setup menu to tell it to put luma only on pin 19

[ADLANCAS]

I´ve already seen the same noise.
Cable was not so good pluged into the card.
I hope that helps.

Alexandre

[SeeMoreDigital]

It looks like your satellite receiver is not able to puke out a proper s-video signal, which is the most probable reason why you're seeing so much chroma and comb filter type noise!


Cheers

[FlimsyFeet]

Yes, what Arachnotron said.

The SCART on your receiver will output composite video unless you specifically tell it otherwise, by selecting the correct option in the setup menu or a switch on the back next to the socket.

Feeding composite video to the s-video connector of your capture card will produce that kind of noise.

[Arachnotron]

On an added note: I just found out my DVB-T receiver can only do composite and RGB, not s-vid and I have heard from other people whose receivers have the same limitation. The central processors in the boxes can do it, but for some reason many manufacturers don't use the option.

So if you cannot find a s-video option in the menu, you are limited to capturing composite.

[MarcN]

Hello!

First of all, many thanks for all your suggestion. Unfortunately nothing has help so far. However I can now basically rule out the adapter OR the satellite receiver for causing the noise. I connected a DVD Player with a SVideo-Out to the card and got the same results. I doubt it’s the cable because any other connection with it is fine. So I guess it has to be the capture card that is responsible for the noise.

Marc

[Arachnotron]

Now that you mention this I remember having this issue with a terratec Cinergy 400 card (= saa7134) I had encapsulated in metal plates (shielding experiment :) ). I attributed it to overheating at the time. It would come and go, sometimes the card would function normally.

I replaced the card with a fresh one and the problem went away. Same PC, same windows installation.

[joegib]

Originally posted by Arachnotron
On an added note: I just found out my DVB-T receiver can only do composite and RGB, not s-vid and I have heard from other people whose receivers have the same limitation. The central processors in the boxes can do it, but for some reason many manufacturers don't use the option.

So if you cannot find a s-video option in the menu, you are limited to capturing composite.

If it's important to you, converters are available that take the RGB output from the digital receiver and convert it to s-video -- see here:

http://www.maplin.co.uk/Module.aspx?ModuleNo=30782&TabID=1&source=15&WorldID=&doy=24m12

I use this kind of set-up -- Freeview receiver --> RGB/S-video converter --> analogue TV capture card -- for TV video capture. Works pretty well.

[MarcN]

Hello

According to this thread -> Analogue Capture Cards (http://forum.doom9.org/showthread.php?s=&threadid=87266&perpage=20&pagenumber=1) (especially last post) SAA7134HL based cards might be treating S-Video input differently than composite one (comb filter). Could this be the reason for the noise?

Thanks Marc

[rotty]

Ive seen this in S mode on Toshiba sets, is this the TV you are viewing on. Its a strange non-crawling 4.43 pattern.