Do capture cards clean the signal ?

[davexnet]

Hello -
I connected the cable box to my almost 20 year-old consumer VCR (not S-video)
and recorded a short clip of a live newscast onto tape at EP speed, which I then
played back and captured (through a composite connection).

My tuner/ capture card is an Avermedia M780 combo from two years ago.

The first thing I noticed is that the picture looks cleaner than playing the VCR and watching on the TV.
I do see some slight jitter, but in general, the capture looks better than I had expected.

I don't have any family video's or anything I would consider particularly important on VHS.
But I do have 100's of tapes, mostly TV shows and movies recorded
from the mid-eighties to the late nineties, which one day, I may unpack from the moving boxes
and re-visit. There just might be something worth saving in there.
Here's a clip from the actual capture, unmodified. ( < 8MB)
http://www.mediafire.com/download.php?zndidzmg2m5

[edDV]

Capture cards vary. At a minimum they separate luma and chroma for A/D to YCbCr. All is a somewhat lossy process so best result is minimal damage. Some cards attempt to adjust levels (AGC). This is usually undesirable.

I downloaded your file. It is typical for a cable box capture although somewhat over sharpened. I see you used a 7.9 Mb/s bit rate to MPeg2.

Did you watch full screen? My CRT TV looks much better than your capture. My LCD HDTV shows similar digital artifacting.

[davexnet]

Thanks for looking at it. It's the Time Warner digital cable, converted in the cable box, and output
through composite to the VCR.

It looks terrible at full screen, very little detail, but I'm not surprised.
It's from a tape recorded at EP speed - there isn't any detail on there to begin with.

I recorded it in the Avermedia Media Center software, the 8mbps DVD compliant mpeg seems to be the default.

When you say your CRT TV looks better, what are you comparing? A "live" broadcast compared to my capture?

My point is, if I create a DVD from the clip and play it back on the DVD/TV, my guess is that it will look quite
close compared to playing back the tape - No ? Would I get better results with one of the Canopus' boxes
and DV capture?
Would I get a better result using an S-video deck and cable? Even though the tapes are only standard VHS?

[edDV]

EP VHS recording will limit quality, particularly signal to noise vs. SP. But SD cable source isn't that good anyway.

Your Avermedia M780 encodes to MPeg2 on the fly in hardware. At 8Mb/s you should get close to the same quality on a DVD playback to TV. You could get near as good at 6Mb/s or even 4 Mb/s for TV captures. Shaky home camcorder video should always use the high bitrate setting.

The Canopus box may do better with higher quality source particularly if you expect to edit. The DV codec is less lossy for recode vs. MPeg2.

Better still for high quality source would be uncompressed capture using the huffyuv codec. This would have lowest loss post editing. DVD MPeg2 encoding would be done at the last step.

VHS records luma and chroma to tape separately. Playback from an SVHS deck with S-Video out avoids combining Y+C to composite and then separating again at the capture card. This gives some better quality.

[davexnet]

Interesting. The reason I was experimenting with the EP speed is that most of the tapes
I've rat-holed away are at that speed. I'm not sure if I can record to HuffyUV with this card?
Never tried anything except the Avermedia MC software. A number of years back used VirtualVcr / Huffy with
a Radeon VIVO which worked pretty good.

I looked into the Aver MC settings further and there is a bunch of adjustments for the analog input.
All the usual picture adjustments, including sharpness.

Thanks for the SVHS info - I'll bear that in mind if I have something that demands a little more attention.

[edDV]

EP recorded source lowered quality during recording. You can't do much to improve it on playback.

Mpeg doesn't do well with noisy source.

[davexnet]

Yes, of course. But I'm probably like many others - suddenly realizing they've all these old tapes at the back of the
cupboard they recorded years ago. Lets face it, probably 95% of the stuff on these tapes isn't worth the effort.
But for the handful of items that may be worthy, we're stuck with them as they are.

My card, right in the Aver MC setup, can record to AVI and even WMV. I expanded the AVI tab and just about all the
thing I have installed (divx , FFdhsow,etc,etc) showed up in there. Seems like if I install Huffy, I can use it this way.
I'll have to check this...

[edDV]

Yes, of course. But I'm probably like many others - suddenly realizing they've all these old tapes at the back of the
cupboard they recorded years ago. Lets face it, probably 95% of the stuff on these tapes isn't worth the effort.
But for the handful of items that may be worthy, we're stuck with them as they are.

My card, right in the Aver MC setup, can record to AVI and even WMV. I expanded the AVI tab and just about all the
thing I have installed (divx , FFdhsow,etc,etc) showed up in there. Seems like if I install Huffy, I can use it this way.
I'll have to check this...

I'm not familiar with that card but similar cards have hardware encoding for Mpeg1 or MPeg2 but rely on software codecs for the other formats you mentioned. If you aren't planning to filter or do effects, MPeg2 is most efficient and can be cut editied and authored directly to a DVD. The noisier the source video, the more MPeg bit rate you should use.

For the type of video you showed you can use MPeg2 at 2 to 4 Mb/s for adequate quality. That will get you 2-4 hours of material to a single layer DVD. See https://www.videohelp.com/calc

Since MPeg2 encoding is done in hardware, you can use the computer for other purposes while capturing. For computer playback, consider 352x480 resolution.

Alternate is software encoding to divx or xvid for greater compression. This will require heavy CPU usage during encoding.

Don't underestimate the time required for a project like this. I scan and hand log the tapes on a VCR before capturing so that only usable clips are captured. Like you say, most of it isn't worth the effort but there are gem clips or programs that are worth the effort.

[davexnet]

I se what you mean. It will be a big project when I actually get to it.
Right now, I've just been exploring the possibilities with a handful of tapes I had laying around.
But I've got two big packing boxes with probably hundreds of tapes and I take what you said -
it's going to take a *lot* of time.

I made a mistake in my initial statements of the Avermedia Center software. It's actually quite limited.
Under "AVI" only Divx 6.85 shows up. Not sure why FFDshow and others are missing. HuffyUV did not show up
so that's not an option in this software. I had a really old install of Virtual Vcr from the old Radeon Vivo days
but it's not worrking 100% with this card - I couldn't for the life of me get the preview to appear with sound no matter
what I tried. One thing though, Huffy and all the others showed up in there.
I tried Virtualdub to capture and received a high percentage of dropped frames - not sure why that should be.

At his point, I'll probably look around to see if I can find any other SW that may be better for the capture.
Thanks for your comments.

[edDV]

I tried Virtualdub to capture and received a high percentage of dropped frames - not sure why that should be.

With which codec and settings?

[davexnet]

edDV - I'll have to get back to you with the details. I did a trial run this afternoon, and my son has since hjacked my PC.
It's the first time I've used Vdub for a capture, and I'll fill in the info here when I can.
I was using Huffy.

[edDV]

edDV - I'll have to get back to you with the details. I did a trial run this afternoon, and my son has since hjacked my PC.
It's the first time I've used Vdub for a capture, and I'll fill in the info here when I can.
I was using Huffy.

Virtualdub will not utilize the hardware MPeg2 encoder, so you dropped frames because the hard disk and/or CPU couldn't keep up.

I suggest you use the software that came with the card and capture hardware encoded MPeg2.

[lordsmurf]

Q: Do capture cards clean the signal ?
A: No.

I'm not aware of any that do, not even high end pro cards.
Some DVD recorders can do this, however. The LSI chipset JVC series, for example.

Using a good VCR is key here. See the list of the best VCRs for converting tapes.

You could get near as good at 6Mb/s or even 4 Mb/s for TV captures. .

There's no way to get "good" MPEG quality at 4Mb/s at 720x480 from a home source -- especially not from alive MPEG capture. You should know better than that. At 352x480, sure, it would be good.

[edDV]

Q: Do capture cards clean the signal ?
A: No.

I'm not aware of any that do, not even high end pro cards.
Some DVD recorders can do this, however. The LSI chipset JVC series, for example.

Using a good VCR is key here. See the list of the best VCRs for converting tapes.

You could get near as good at 6Mb/s or even 4 Mb/s for TV captures. .

There's no way to get "good" MPEG quality at 4Mb/s at 720x480 from a home source -- especially not from alive MPEG capture. You should know better than that. At 352x480, sure, it would be good.

I meant adequate as opposed to excellent. For news clips and such @4 Mb/s, the user needs to choose compression artifacts at 704x480 vs mild pixelation at 352x480. Alternative is longer software encoding to divx/xvid/h.264.

The user needs to evaluate the options and create a capture/edit/encode strategy. The trade-offs are picture quality, editing convenience and file size. For archiving old VHS news clips I'm more interested in editing/encoding speed rather than picture quality or disc space. It is the content I'm after and my time is valuable. If I like a clip, I may go back and do a second capture/encode for picture quality.

For my needs I use two methods.

1. For simple "cut editing" of programs or segments, I'd capture to MPeg2 with a Hauppauge PVR card, then cut out the segments I want for archive.

2. For complex search/scan review of material, I capture to DV format which is much faster on the timeline, then cut out and encode clips of interest.

I optimize for picture quality when the VHS material is a camcorder original, or a unique copy. In that case I archive to DV or Huffyuv so I can work on them later.

I don't waste time capturing VHS TV shows or movies that I can rent from Netflix. Often the commercial breaks are more interesting to me.

[davexnet]

It makes sense - if your source is an old VHS tape recorded at EP speed, there are many problems right on the tape
recording itself. It's fuzzy, it lacks definition, side to side jitter, possibly over sharpened and other artifacts.
(I just remembered My old Sony VCR has a DUB mode which I failed to engage for the test clips I made.
I'll try it and see what the difference is. What does it do? Bypass the sharpness circuit ?)

So to my mind, I want to use enough bitrate that I don't see digital artifacts along with the other problems
mentioned above. If I do, I'll up the bitrate. I used a clear, live news cast to make my test tape,
I consider that's the best picture I'm going to get @ EP speed, the old tapes I've stored away are more than likely
in worse shape. The signal out of my cable box is much more likely to be good - very good compared to the
picture 10 or 20 years ago. I guess the technology at the cable company, fibre optics, better conversion boxes,
etc,etc. I found one of my old tapes with a movie recored from showtime about 15 years ago. Ity's so murky
and indistinct it's virtually unwatchable. But it's not tape degradation, thats the way it was when it was recorded.
Dodgy analog cable, poor converter boxes,etc,etc.

One interesting thing, when I opened up the very old Virtual VCR, although it wasn't working properly. (silent preview)
it successfully captured Huffy stream (with audio) and without dropped frames. Only in Virtualdub did the frames drop.

[edDV]

One interesting thing, when I opened up the very old Virtual VCR, although it wasn't working properly. (silent preview)
it successfully captured Huffy stream (with audio) and without dropped frames. Only in Virtualdub did the frames drop.

Are you capturing to an internal drive other than the OS drive?

That is standard practice for Huffyuv. You are pushing the limits of a PATA/SATA depending on settings.

[davexnet]

I do have two drives but I inadvertently set Vdub to capture to the OS drive.
I'll defrag the other and retry when I can set that as the target. When you say settings, are you referring to
settings in the Huffy config window? There didn't seem to be too much left all @ default, except I turned on multi-thread.
(I downloaded that MT version from the tools here @ Videohelp).

[usually_quiet]

Your card may make the signal look a little better in some ways, even though it doesn't have a built-in cleaner.

It has a 3D comb filter built into the video decoder, which is there to reduce some kinds of video artifacts, such as dot-crawl noise and ghosting, when using a composite connection for the source.

[davexnet]

Your card may make the signal look a little better in some ways, even though it doesn't have a built-in cleaner.

It has a 3D comb filter built into the video decoder, which is there to reduce some kinds of video artifacts, such as dot-crawl noise and ghosting, when using a composite connection for the source.

Thanks for the info. Perhaps this is what I'm seeing. I am using composite, because my older VHS VCR
that's connected doesn't have S-video. Earlier I had captured some family footage shot on Hi8 via S-video,
and the result was most impressive.

An update about the Virtualdub/Huffy situation - I was able to successfully capture with out dropped frames
after making one change in Vdubs setup... This setting, under capture/timing, selected by default "drop frames when captured
frames are too close together" (what ever this is for) - I deselected this and the problem was seemingly resolved.