Cature Resolution with WinTV

[GaryAllegra]

Why can't I capture using my WinTV PCI board at full (640x480)resolution? I'm using AVI_IO and at full the buffer overruns. If I use the utility that came with the board it drops frames like crazy.
I can capture at 720x480 from a Dazzle D/V Bridge thru firewire. I just can't use it to capture RF. I guess I could take the RF thru a VCR then to the D/V Bridge but I also need to schedule the captures when I'm not home which AVI_IO does.
I have a new HP Pavilion, Pentium 1.8 Ghz, 640mb ram, 120B HD. It can't be the PCI bus because the firewire goes thru a PCI card! If the WinTV board can't handle it why is it an option? Any help would be appreciated. Thanx.

[JHebert]

Your system should be able to easily capture full frame 640x480. I can do it and my system is only a P3 800 with a similar BT878 card.
Are you capturing uncompressed AVI with the WinTV card? If so you should try a codec like Huffyuv or PicVideo MJPEG instead to compress the video stream so your hard drive can keep up with the data transfer rate. Huffyuv is lossless so the quality is identical to uncompressed AVI. PicVideo MJPEG is somewhat lossy but at high quality settings it is excellent.
Make sure your hard drive has DMA enabled and that it is defragmented. Also check that you are using current drivers for your WinTV card.
Quit any other programs when you are capturing.

[GaryAllegra]

Yes I have DMA enabled and yes I'm trying to capture uncompressed AVI. I will try the Huffyuv codec. Thanks!

[GaryAllegra]

Forgot to ask. Does the Huffyuv codec produce an MPEG? I really need to stay in AVI for editing and encode to MPEG at the end.

[TheInformer]

Gary:
HuffYUV produces a lossless AVI file. You typically get a 2.5:1 compression over uncompressed AVI files. What's thrown out is data that's not shown or heard, such as sync signals.

[GaryAllegra]

Thanks much. As you all know, this learning process can be very time consuming. This forum has helped immesureably! I've been at this since December and just now consider myself not a newbie. The problem with all this is everyone has a different computer, different A/V hardware, different software, so what works well for one person is a disaster for someone else. I think of all this as a challenge - up to a certain point, but it's a big relief that I don't have to go it alone!
I know some of these questions get asked over and over and I think I can speak for everyone who has benefited from this forum that we appreciate your help and patience. I hope that soon I will have enough knowledge to help someone else.

[Scobo]

GaryAllegra, have you tried capturing straight to MPEG ?
I have a WINTV card and find that I can't capture higher than 352x288 without dropping frames in AVI format but I can capture up to 480x576 (PAL SVCD) in MPEG2 with Ulead Media Studio Pro.
I get no drops capturing from a good quality source using a Duron 750Mhz and 384MB RAM.
I have to turn overlay off and capture in preview mode but this gives great results with high bitrates (5000kbps or higher). The quality at low bitrates is not as good as encoding an AVI but if you intend using your PC for playback or have a DVD player that plays high bitrates this is a great method. Hauppage has a program called NanoDVR on its website which also captures straight to MPEG2 but I don't get such good results with this on my system.

[GaryAllegra]

Scobo,
Yes, MPEG capture does work well with the WinTV board. The problem is, have you tried any serious editing using MPEG files? I've tried editing MPEG's in Premiere and Studio 7. It's extremely tedious. (for example: dragging a timeline thru a 30 min video causes a 20 sec. wait). Also, after editing I would need to re-save as MPEG. Something I've been told not to do because of loss of quality. If I can't solve this problem I think I would still be better off capturing AVI at the lower res. I'm still relatively new at this, so if I'm missing something please let me know. Thanx!

[GaryAllegra]

I forgot to mention. The purpose of the captures is to end up with MPEG-2 files after editing, to burn to DVD to be played on set-top players.

[sitlet]

yeah i have a wintv pci board too and they are not made to capture full screen video. they r pretty good with mpg but i do a lot of editing too and i know how long mpg's take to edit. try using the huffyuv, it works pretty well. or even try using the divx codec. i just kept experimenting and found out what works best on my system.

[JHebert]

GaryAllegra, one more possible issue if you are running Win 2000 or XP is that these systems use the newer WDM (DirectShow) type of drivers instead of the older VFW (Video for Windows) drivers found in Win 95/98.
Many popular video capture apps like AVI_IO and Virtual Dub are based on the VFW standards, and so when you use them to capture in a system with a card using WDM drivers, an additional "wrapper" or "mapper" layer of software is used to translate between VFW and WDM.
I don't know all the technical details of how this works, but the upshot is that this combination often limits you to 352x240 captures, even if your system is fast enough to do higher resolution captures.
If you are running Win 2000 or XP you could try the capture program iuVCR which is a "native" WDM capture program that works with most WinTV type cards and might enable you to capture at full resolution.

[Scobo]

GaryAllegra,
I use TMPGEnc to trim my MPEGs with the Merge & Cut tool. This is far easier to use than the likes of Premiere or Ulead Media Studio Pro but is limited to simple trimming and merging of clips. It's also pretty quick at outputting the final file and the quality is not affected (it does not re-encode). MPEG is notoriously difficult to edit though.
I have been considering upgrading my system to capture at higher resolutions. You mentioned that you capture DVD standard MPEGs. Are you able to capture 720x576 with your system ?

[GaryAllegra]

I capture 720x480 avi with my Dazzle D/V Bridge. I then convert to MPEG with TPMGEnc or sometimes, if size is not an issue, let DVDit PE do the MPEG encoding. The difference is TMPGEnc does variable bit rate encoding while the encoder in DVDit uses constant bit rate.