Is it possible to capture in DV-format from an analog source

[Spielberg]

Does anybody know if it is possible to capture DV in realtime from an analog source with the Marvel400?
I tried the following:

- Apply the YUY2-patch from Flying Dutchman
- Specify a custom resolution in AVI_IO of 720x576 (this is required for DV)
- Use the MainConcept DV codec for compression

AVI_IO didn't complain about the settings but produced a file with only noise (the sound was OK). This makes me believe that the Marvel doesn't support 720x576 captures. Or does anybody know a trick (registry hack?) to get this working?

Spielberg

[dchip]

I think "DV Format" involves more than just the size of the picture or resolution. To capture DV you would need equipment designed to capture DV. As far as I know, the Marvel G400 does not fit that category. I am certainly no expert on the subject so continue to look into it.

[Dr Mordrid]

The Matrox hardware is hard coded to only support up to a 704x480 frame size for NTSC and 704x576 for PAL.

This complies with one of the ATSC A/53 Annex A Table 3 standards and is used so its 352 wide half and quarter frame captures are MPEG compatable. MPEG requires the frame width be evenly divisible by 16. 352 is and 360 (half of 720) is not.

What may work is the Hauppage WinTV theater. It's capture formats are not hard coded and can be set to capture at custom resolutions up to 768x576, including 720x480.

Dr. Mordrid

[Rob100]

You could capture as Huffy 704x576 and then add 8 pixels to LHS and RHS using AviSynth or Virtual Dub and compress to DV? Not ideal, but a solution I guess...

FYI WinTV Radio supports 720x576 captures without problems.

[Spielberg]

Thanks Dr. Mordrid, that was the info I was looking for.

Rob100, thanks for your suggestion. In fact I have done this and it works quite well, except that HuffYUV takes 3 times as much space as DV (10 MB/sec vs. 3,6 MB/sec) which limits my recordings to about an hour. I will have to buy a bigger harddisk :-)

The reason I wanted to do it in the first place was to be able to record a movies of let's say 2 hours and afterwards convert them to DivX.
I found out that DV->DivX conversion works better than MJPEG -> DivX. Realtime DivX compression in fullres doesn't work on my PIII/800MHz.

But for small clips of homevideo footage, the HuffYUV solution works perfect.

Spielberg