Help on Poor AVI Capture Please Please

[MickB]

I’m still pulling my hair out trying to figure out why I have poor AVI capture from VHS or 8mm tape. I read on here about how great VirtualVCRis and tried it last night. This produced much better results at 320.x280 but not at 720. I have used many other programs and no matter the settings, codec, etc. they don’t have an affect on improving quality. I compared several captures at 320 using other programs but VirtualVCR was considerably better at this 320x280 setting than say, Studio 8. When I changed VirtualVCR resolution to 720x480, the AVI became degraded again.

I’m trying to capture at 720x480 or thereabouts, and need help. Why is the picture becoming so fuzzy and darker objects appearing with horizontal lines around the edges? I definitely get dropped frames at the 720 but none at 320. Data bit rate tests on both my drives are okay.

I’ve heard two scenarios, neither of which I know where to make the changes.
1. My second hard drive should be connected to a Promise ATI 133 card or to RAID controller on my motherboard to keep up with the speed.
2. Interlacing problem but I have not found settings in Studio 8, VirtualDub, TMPgDVD, VirtualVCR, etc., that seem to have an affect (can’t find most interlace settings anyway).

Below is a link to a still shot where you can see the lines. Scroll down to se the photo.
https://www.videohelp.com/forum/viewtopic.php?t=214013

I’m using an ATI AIW 9700 card and huffyuv codec running on a P4, 2.8 ghz, with 1 gb ram.
Thank you.
Mick

[babyboo]

A couple of things...

The larger the resolution the more bitrate you are going to need.

If you are using the SAME bitrate for 320x280 and 720x480 that will contribute to the problem you are experiencing. 720x480 requires a very high bitrate for VHS to look somewhat decent if at all. Actually it is overkill. You can pump the bitrate all the way up but your file will get quite large, and you will be wasting a lot of bits on noise. You could get away with less than half the bitrate at 352x480 (which you should consider if you ever want to put onto a DVD as this resolution is DVD compliant...320x280 definitely is not)

The horizontal lines could be due to interlacing which I know you wouldn't have problems with at the lower resolution as you are only capturing a single field as opposed to 2 when you capture at 480.

If you want you can either capture to 352x480 or 640x480 interlaced at a high bitrate and then resize to 352x480 (if you are in NTSC land and you plan on playing on an NTSC TV)

[MickB]

babyboo,

Thank you for the info. I was wondering about the high resolution and if it was really needed. I will try your suggestions and see what happens. I also have some 30-year-old VHS tapes that I did not want to lose quality on, hence the attempt at higher resolution.

I don’t recall seeing a bitrate box in VirtualVCR that I could change. Can you suggest an approximate bitrate I might attempt at the 640x480. Thanks.

Mick

[MickB]

By the way, I am planning on buring DVD's with the captured files.

[J3M]

Try an average VBR of 4.5mb with a max VBR of 6mb for half D1, or for full D1 try an average VBR of 6mb with a max of 8mb. Those bitrates work very well for me when capturing from VHS. If the tape is really old, I MAY bump up the average bitrates just a bit to help compensate for all the noise. BTW, those rates are for files I plan on putting on a DVD also.

[MickB]

Sorry, but setting a bit rate seems to be missing from my brain. I can't find a bit rate in Studio 8, Virtual Dub, or VirtualVCR. At one time, I understood D1 and D2 but not now. It appears Virtual Dub captured at about 9-10,000 data rate but still poor video with horizontal lines around the darker images. The higher I set the resolution, the worse it gets.

[J3M]

What kind of a TBC are you using? I may have skipped over it, but I didn't see anything mentioning that in your other posts.

I have Studio 8 as well, and I don't think you can set a bitrate with it. It defaults to certain bitrated depending on the quality settings you are using. I've not used VirtualDub much yet, but I do believe you have complete control over bitrates with it (but don't quote me on that).

VHS to digital is a tough thing to get down, or at least with good results.

BTW, D1 is full DVD resolution of 720x480 and half D1 is 352x480. Both are DVD compliant resolutions.

[mmasw]

....

I’m using an ATI AIW 9700 card and huffyuv codec running on a P4, 2.8 ghz, with 1 gb ram.
Thank you.
Mick

well....this is just one guy's opinion but here goes:

unless you plan on doing extensive after-capture editing, I don't see any advantage in capturing to HuffYuv. You have an ATI Card that can capture directly to DVD-Compliant MPEG-2 and you have the video soap filtering functions available...at least you should with your cardand MMC.

I'd guess that any increase in video quality you'd gain from the Huffy capture versus MPG-2 capture, you will most likely give back in the encode.

Your source is analog anyway....there's a ceiling on the quality of capture, And the ATI does a pretty good job of approaching that ceiling utilizing it's MPG-2 capture functions.

Of course this is assuming you are heading for a dvd from the captured video....if you have other plans, disregard my opinion....

[MickB]

I appreciate the comments. For whatever reason, the record button will not activate on the ATI AIW software so I've never captured using it. I do plan on editing AVI then converting for DVD burn. A friend just gave me and external capture device to try and I will see if that fixes the problem. Thanks.

[henasau]

I have problem with captured video quality too.
I heard in several posts about increasing bit rate.
I have plenty of the disk space and would like to experiment.
Likwise MickB I can't find any option for setting it in Vdub and VirtualVCR. Can someone explain this to us please.

[MickB]

Well, I just switched to a completely different capture device (external). Not sure about settings yet but so far, the video capture is about the same, degraded with the horizontal lines around darker objects. This is completely bypassing my ATI AIW 9700 card with all different cables, so I'm assuming it's not my capture devices.

When I plugged this unit in (firewire) it recognized Studio 8. I had to change the capture sourse to DV to see any preview. Not sure if that is normal but it would not see it using the only other selection, my ATI card. No dropped frames using this external device at 720x480 just lousy video. VirtualVCR and Virtual Dub do not seem to recognize it.

So what the heck is the problem? Only other thing I know to try is to remove my second hard drive from the piggyback cable and try to connect it through the RAID controller so data accesses faster.

[MickB]

Here is another update: I used another older camcorder as the source but still have the same poor AVI capture results. Having eliminated everything but my motherboard and hard drives...any suggestions?