Is visible analog interference common on capture cards?

[justinluck]

I am currently using a DVICO Fusion HDTV3 card to capture analog video. I am hoping to use a Sapphire Theaterex 550 card if I can ever get it to POST in my computer!

But anyway, what is bothering me is that everything that I capture on the Fusion card is riddled with interference. What I call interference are these horizontal lines that continually move up or down the screen. They are kind of translucent and hazy...hard to describe, but I'm sure all of you have seen what I'm talking about. They are distracting to say the least, and I really want to have a solid picture. Do you think it is the Fusion card, or do most capture cards suffer from this type of interference because of the surrounding computer hardware?

[vhelp]

Can you post a pic demonstrating this phenomina ?

However, IMO, its the mobo/cpu that is causing this mostly.
I did see a thread topic elsewhere's on this issues (I think doom9)
and someone had posted a BIOS HowTo as an might-be solution.
(I haven't tried it on my pc though - yet)

I have experienced this phenomina for many years, ..and is another
reason why I went for the ADVC-100 device.
(Note, this does not mean that I left Analog Capture cards)

EDIT:
One more thing you could look at, with respect to your capturing codecs.
Try the following, and note weather or not *one* or *the other* is more
noisy or not:

* huffy (YUV)
* uncompressed (RGB)

--- end edit

-vhelp 3356

[justinluck]

Wow, well it took FOREVER to get a file small enough to upload and still show the interference correctly, but here it is. I had to save it as a WMV file...long story. But look for the constant faint horizontal lines moving up the picture.

http://s22.yousendit.com/d.aspx?id=2PXWABJKILZYH0AWG0HP1OJGK7

[justinluck]

Any comments? There is no audio because I can't get the Fusion card to behave properly with my onboard sound through the external input. That is why I am counting on the ATI 550 chip so I can input the sound through the PCI bus.

[redwudz]

I ran the video several times. Couldn't see any lines running through it when played back on WMP, just the usual noise at the very bottom. Does the finished video show it when ran on a settop player? I've got a Fusion card and never noticed any interference.

[justinluck]

The compression in WMV encoding tends to hide it. I will output an mpeg version as soon as I can get it working right. Capturing with the Fusion card has given me any headaches.

For example, I tried recording Conan O Brian with the Fusion software as an mpeg file. Well, when I played it back, I found that it recorded the top left corner of the screen at full HD res. Meaning, even though I was watching a scaled down version to fit on my desktop res, the recorded version captured what would fit on the screen if the image was displayed at full res. So instead of seeing Conan, all that was captured was the top left portion of the studio...nice blue curtains

Recording it as a tp file did not give me this problem.

[redwudz]

I'll try plugging my Fusion card into cable and do a analog capture. I usually only use it for HDTV OTA. Might take a few hours as I am encoding a video with the machine at present.

[justinluck]

These are the lines I am talking about. They aren't discrete lines, but like greyish areas that form thick horizontal bands. They are more visible in motion because they rapidly move up the screen. Some times they speed up or slow down. They can also change direction and go downward. It doesn't matter whether I play a video, or what source I plug in to capture. The lines are always there.







See them now?[/img]

[redwudz]

I think I see what you mean. You might try going into BIOS and looking for 'Spread Spectrum' and changing the setting there. That should have some changes in internal interference in the computer. You may have tried moving the PCI card already to a different slot, but that sometimes helps. I'll let you know if I get them in analog capture later today.

[justinluck]

Here in this shot, you can easily see the interference while I'm on blue screen with the JVC 9911. It is interesting how the speed and direction change without me moving any components around.

Do you guys think it might be coming from my outlet? Or my PC? Is it my powersupply? Motherboard? I wish I knew more about EMI...

[Coop]

you have what is known as "ground loop" interference which manifests itself in a couple ways. Usually in audio humming, but also in the horizontal bars you are seeing in your captures. It's usually caused by a large appliance (stove, refrigerator) etc on the same circuit as your PC but can be caused by a multitude of other scenarios as well.

I upgraded my capture card from a Gainward Ti4200 to a FX 5950. I was getting audio ground loop with the Ti but not video interference - upon upgrading I noticed the horizontal bar issue as well. Some cards do a better job of filtering than others.

I ended up solving this by purchasing an expensive Monster power strip with coax filtering as well, and that did the trick.

[redwudz]

justinluck, I Tried analog capture with my Fusion card. No lines, bars or otherwise. The picture is clean, just cable noise from the crappy local system. I tried VCD mode and DVD mode, MEGs.

It does sound like RF interference. Have you tried inputing with a VCR to see if it's from the cable? If it only appears when cable TV is hooked up, check your cable where it enters the building if you can and make sure there is a ground stake and grounding block securely connected. A AC line filter may help, but there's no guarantee.

If you are in a newer building with all 3 wire outlets, probably not coming from the power company. Do you get any interference from appliances running? That's a usually a sign of poor shielding in the computer or cables. Any florescent lights nearby or lamp dimmers? Those can both cause RF interference. Also if a TV is very near your computer or cables, you can get interference.

Anyway, that's all I can come up with. At least with my Fusion card, no interference.

[justinluck]

Coop, as you mention it, I do have a mini fridge hooked up to the same receptacle. But when I unplugged it, the problem did not go away <sigh>. Tomorrow, I go look for line conditioners. I really don't want to spend ~$80 for the Monster Cable device, but I guess it may turn out to be my only choice. I also get a slight audio buzz that you talked about.

It's not from the cable. Something from the wires... who knows. But I'm determined to fix it with one thing or another.

I'll report back when I resolve the issue. Wish me luck

[gshelley61]

I have terrible ground loop noise on my computer capture card (AverTV). I tried a line conditioner, didn't help. Another reason I basically quit analog capturing with the computer and have switched to standalone DVD recorders. No interference noise and a sharper, clearer picture.

[justinluck]

I'm going to the store today and will see what I can find. I finally know the correct terminology for those darn horizontal bands though. Interference bars!! Learned it from a google search. Neat

[SLK001]

I'll be damned if I can see what you are talking about. And I am an RFI expert.

[canadateck]

I'll be damned if I can see what you are talking about. And I am an RFI expert.

Here's a better view of what he's talking about.

[SLK001]

An here's an even better view. Do the lines move in a rolling fashion, or are they stationary?

[justinluck]

The lines are rolling. I usually see them moving upward, but they can slow down, go to a standstill, and then reverse and go downward. The speed is always varying.

[vhelp]

Yes. I seen them in mine too - rolling. Usually up and/or down.

I can see these bars pretty well. I have an LCD monitor, and these tend
to show more detail clearly. PC and TV tubes tend to hide them a little.

I've ben there with this noise issues for a long time. But, like I commented
earlier, its narrowed down to the mobo/cpu/chipset; and/or capture card;
that is causing the problems.

The blue-screen (vcr trick) is classical in demonstrating *any* noise.

One of the last trick I used in eliminating any outside interference,
(aka, taint) was a 12volt battery w/ a power invertor built-in. Mine
is a jump starter kit (about 10lbs) in one unit. Anyways.

In my last attempt, I hooked up the following:

* PC
* LCD monitor
* and, vcr

..to it (total 300 watts) and I was able to run a battery of tests. In the
end, I continued to get the lines. So, my theory still holds (for my setup)
that it is one of these:

* mobo/cpu/chipset;
* and/or capture card;

The tests I ran were with the following:

* Satalite (directv) receiver
* DV cam
* various vcr's
* my dvd players ( ad-500 and ad-1500 )

and all produced certain levels of those blastit Line Noise. The sample
I posted back then, was the same as justinluck 's

My suggestion is like this ...

If can find out what other's here are using (mobo/cpu/chipset and capture card)
(and if monies is w/in reason) ..go out and by one of these mobo's and test
again. If you get some issues, chances are that those who are saying that
they have no Line Noise in their source's are just not seeing them, (because
of the "tube" is hiding them) and that they are there after all - period.

And last, as I've said, I resorted to a hardware device ( advc-100 ) and
no more noise..

--> ZERO Line Noise and

Good luck,
-vhelp 3359

[justinluck]

Yes, vhelp, I'm sure that you would agree these interference bars are rather annoying to look at and would not want them included in your backup of VHS to DVD

If some people don't notice them, that's great, but I can see them easily and I don't think I'm being too picky for wanting them gone.

I know some of you are experts in this matter so maybe you could point us in the right direction. I don't have any knowledge of electronics, but I am thinking one source of these bars could be from the tuner itself. Maybe the tuner is always picking up errant signals even when it is not in use and that is what is bleeding into the composite and s-video modes?

What do you guys think?

[vhelp]

>> ..would not want them included in your backup of VHS to DVD

yes. Especially for VHS sources
..they are most obvious with VHS sources.

-vhelp 3360

[vhelp]

As for the tuner theory. I've been there. I thought the same thing.
And, I resorted to buy a bunch of cheap cards w/out tuners, but in
the end, the noise was still there -- double

-vhelp 3361

[justinluck]

Ok, this is what I've tried so far today:

Moved all the computer wires to plug into one single powerstrip so they are all connected to the same ground wire.

Unplugged the microfridge that was using the same receptacle.

Unplugged the wireless router that is on the other side of the house.

Unplugged the computer from the cable tv.

With all these steps, I still get the hum bars.

One thing I do notice is that the vertical bar that looks clean moved slightly to the left. Look at the old capture pics and notice the vertical space that was free of the bars.


Now look at this new capture:



See how the vertical space moved to the left?

[justinluck]

Here are three short captures of it on blue screen so you can see it in motion.

Let me know if you also see weird glitches when viewing this in Windows Media Player. This first one was recorded as an mpeg-2 at 640x480. For me, there are strange glitches on the bottom and right side of the screen in media player. See flashing neon green bars?

http://s22.yousendit.com/d.aspx?id=0U0RDEHQCSJN0X276I2OCM37N

This second one is mpeg-2 at DVD res, 720x480, look how the bars are now moving up:

http://s22.yousendit.com/d.aspx?id=2IOYF137OFXVW2MIITLTEM0O5C

Notice the flashing neon green bar in the bottom when played in Windows Media Player?

Now look, the bars are moving faster now!

http://s22.yousendit.com/d.aspx?id=074ZJVDP259RJ0GGRDPGQEPPBK

[junkmalle]

The source of your RF noise is probably your motherboard or some other internal component.

[jolphil]

If you see the Bars slowly moving up or down slowly it indicates to me that
it may be some type of beating or (hetrodyning)spelling?..By that I mean two signals are mixing and falling in the video spectrum..This phenomon is somewhat common in electronics ..Its usually F1(-) minusF2 or the difference between F1 and F2 falling in the video range..
My guess, and I could be wrong, is that i see about 21 horizontal bars in the vertical picture..To me,that would indicate 21 times 60 fields per second or around 1260 HZ.. The reason they tend to move is because the two interfering frequencies are not synchronized and drift up or down causing the difference to shift up or down..
The million dollar question is what are the sources of the interference, the F1 and F2?Next question is where are they being mixed or produced?
Almost impossible to answer but you are on the right track by the process of elimination you are doing..
If you had a varistat you could vary the line voltage up or down slightly(+/- 10%) to see what effect it had on the bars..A major change would indicate that the power supply chopper/switching regulator may be one of the offending culperts..It could be almost anything on the MoBo or video card itself even your digital encoder..
I wished I cold help you but all I can do from here offer my thoughts..
Others may have better more specific suggestion and I've seen some good suggestions here..
GoodLuck,
jolphil

[SLK001]

It does look like power supply ripple is getting through to the output (whether 60 or 120 Hz it really doesn't matter). You could try:
1) A BETTER power supply, hopefully one with better output filter capacitors.
2) Try to modify your current power supply filtering (NOT recommended UNLESS you know what you are doing).

I have a capture card that is the same as one of vhelp's (Winfast TV2000) and I don't have this problem. But then, I've always built my systems from the ground up, and always selected good or better parts. If you can afford it, buy yourself a new 400W power supply in the $30 range (at least. stay away from the "bottom of the line" models). Although not always the case, as the price goes up, so too does the quality. You need to find one with a better Power Line Rejection Ratio (but listing specs is not a priority for these manufacturers).

I'll try to dig up the info on my power supply and list it tomorrow. I'll also try to see if I get the same interference as what you guys are seeing.

[justinluck]

Yes, it could be the powersupply, but I wouldn't necessarily categorize mine as a cheap one. I have a Seasonic Tornado and it cost me $75 a year ago. I purchased the Seasonic for its supposedly efficient AC-to-DC power conversion and for its quiet 120mm fan.

I want to thank everyone for their input. I'm learning a lot and really appreciate your help.

[justinluck]

Update:

I went to BestBuy last night and bought a $59 Dynex powerstrip that claims 2520 joule surge suppression, an output of 15 amps 1875 Watts, and comes with an EMI/RFI Noise Filter.

To my chagrin, this did not help

There was a Monster Cable Power Protector that claims Clean Power Stage 1 v2.0, whatever that means, for $79. I don't know if this would be better, but I feel like Monster Cable tends to overcharge for their products and that this Dynex is probably of similar build quality.

What do you guys think?