Can Someone Explain Difference Between DV and MPG Capture?

[ChevyNo1]

When you search the capture cards list, the following is your choices:

RealTime MJPEG
RT Uncompressed
RT MPEG1
RT MPEG2
RT DV

I know RT means real-time. I guess my question is, is a card, like the Dazzle Hollywood, that captures to DV capturing in lossless AVI? So whenever I capture with it, I have to convert from AVI to MPG? If so, does it make more sense to have something that can capture to MPEG2 if I make SVCD's? I'm a relative newbie, but I'm thinking that capturing to AVI ( DV ) and then converting to MPG using Tmpgenc would have better quality than something that captures straight to MPG2, but just takes more time ( and disk space ). My main reason for getting a card is to capture to make SVCD's with really good quality. What kind of card would you suggest!

Thanks!

- Dug

[Greg12]

Yes and No

DV is considered transfering, not capturing so u get a perfect 1:1 copy, no degridation.

Now MPEG is a highly lossy codec. U will loose alot of data. Real time MPEG 2 must be done by hardware encoders or u will get crappy results.


Now normally DV would be better, but if the source isn't DV (such as a VCR tape) then the perfect transfer won't occur because the source isn't perfect.

I would however recomind DV.

[resnullius]

dv when possible is generaly better.

[EricB]

Well, DV is not lossless. Something (video camera, Dazzle Hollywood DV) converts analog video to digital. The resulting file is a "lightly" compressed AVI with a very specific format (ie. 720x480, 48kHz audio, etc for NTSC).

The files are huge (~ 6MB/sec) but are very well suited for video editing. Plus, once you convert to DV, you can then TRANSFER the files to and from DV video tape with no loss. It is a file transfer.

If your intention is to make VCD or SVCD, you still have to compress down to an mpeg. If you have no intention of editing, and your original source is not DV, you might be better off doing a direct capture to VCD or SVCD format. The resulting files are not very good for editing because they have already lost a bunch of data, but they are well suited for burning to CD-Rs.

[Anonymous65]

In a nuttshell, DV is mjpeg in non-interlaced video at 25Mbits/sec video at 720x480 (NTSC). This is a 5:1 compression ratio. The video frame size and frame rate is fixed, so is the compression ratio. The audio is 48Khz sampled instead of the normal 44.1Khz sample frequency.

Mpeg, is variable compression, frame size and frame rate. There is also compression between the frames, and it can be interlaced.