An attack of capturing ignorance!

[devdev]

Hi All!

I'd like to capture one two hour and one three hour vhs pal video onto my pc.

At present, although owning a reasonably hi spec pc, I dont have a capture card.

I'd appreciate some advice on:
1. What's the best way in respect of quality to capture (ie internal card or external capture device like dazzle)
2. Is it best to capture as digital and then convert to mpeg for dvd?
3. is there a time/space limitation - ie 3 hrs of video on one dvd?

thank you in advance!!

[Gazorgan]

Everyone is different.

Since your source is VHS, and your PC has more than enough power, you have multiple options.

1) El cheapo capture card. These have the Ubiquitous BT chipset in them. You can capture full D1 video and Stereo via your sound card(The $29 ones have mono sound). Capture to Huffyuv for best results or MJPEG for space considerations (3 hours can hit 60 GB in Huffyuv). Edit as needed, filter noise and convert to MPEG with the encoder of your choice (TMPGEnc does well). Author with the Authoring tool of your choice.

2) External USB 2.0(assuming you have, 1.1 won't work) or Firewire device. These can run from $200 to over $1000's. Quality can be tter or a lot worse, it depends on the device and the desired end product. Some capture MPEG2 on the fly (as can the $25 cheapo cards), but no filtering.

3) DV cam. If you have a digital camera and a firewire card you can use the A/V passthrough and convert it to DV as you capture.


Problems to deal with: Old tapes are noisey and tend to drop frames. You are going to have to correct your capture to hit 25.000 fps (use avifrate), since I can guarantee you will be off a few 0.001's. VDUB has excellant noise filters to clean up the tapes (requires an AVI or DV capture). You will also have to juggle your bitrates when encoding to MPEG2 to hit a DVDR. For the 3 hour tape look at 1/2 D1 resolution (352x576 interlaced), which is higher than VHS specs. In fact using 1/2 D1 for any VHS capture is quite acceptable.

[SLK001]

Some things that I would like to add. Capturing is HUFFY gives you a color space of 4:2:2. A lot of the external capture boxes (like the Canopus AVDC-100, ext) cap with a color space of 4:1:1. Don't worry about what that means, but just know that HUFFY 4:2:2 is a superior format.

VirtualDub can use only VFW drivers, which are basically obsolete (they are Win98 vintage). The more modern OSs use WDM drivers. But, you do have work-a-rounds for using VFW drivers on the newer OSs.

The Brooktree video chip sets (now known as Conextant) do a very good job of digitizing the video (most use a 10 bit A-D). I recently bought a WinFAST TV2000 Expert card for only $60, and I am more than impressed by its ability. I just slapped the card into my machine, loaded the WDM drivers provided, then tossed the rest of the package. I use VirtualVCR, which is a freeware DirectShow capture utility.

My caps are running about 28GB for a 54 minute session (at 720x480x29.97fps using the fast HUFFY compression ratio of about 2.35:1). If I were to capture your 3 hour video, it would consume about 90GB. You can get better compression using a slower HUFFY algorythm but at the risk of dropped frames (if your computer can't keep up with the incoming data, frames will be dropped -RE:forever lost). I have yet to drop any frames.

You need to fill in your COMPUTER PROFILE so that we may better assist you.

[SatStorm]

Most users use mjpeg codecs like PicVideo for capturing. Those codecs are lossy compared Huffyuv, but for analogue sources like VHS the lossy info ain't noticable at all, even in compression (pic video at 18 or even 17 values!). The benefit of those mjpeg codecs, is the smaller filesize (19/20 value on Picvideo, is half filesize of a huffyuv capture at the same framesize! ). Unfortunatelly, mjpeg codecs are not freeware...

Virtualdub works with vfm drivers, which are not used on win2K and winXP. Thank God, there are realtime converters from vfm to wdm (the current version) called "warpers". If you have a fast CPU (2Ghz +) those warpers work great, but on slowler machines, you might find it difficult to capture at a full framesize.

bt8xx(x) based cards, have great third party driver support, which allow them do amazing stuff. But all captures on those cards seems to be a product of resizing, from a very specific framesize they use for capturing by default. So, for 1/2 D1 captures, they don't show good results, neither for full D1 ones. A good framesize to capture with those cards (not the best one) is 704 x 576/480.
Nvidia and newest Ati cards do a better job on capturing various framesizes beyond 704 x 576/480

And a tip: If you can, don't capture through built in tuners... S-Video / Composite are a much better root, even if you have to record the audio through the line in of your capture card