Re: [libdv-dev] NTSC - PAL conversion?

[Alastair M. <ala...@aj...>]

Dan Dennedy wrote:
> 
> I know someone who has used MainActor on Linux to do this. I believe you
> need to capture AVI type-2 files for use with MainActor. Then, you could
> use Kino to send the AVI files. It might be more valuable to write
> something that can be contributed tho :-)
> 
> +-DRD-+
> 
> Alastair Mayer wrote:
> 
> > Hi,
> >     I have about three hours' worth of NTSC-format DV files that I
> > need to convert to PAL format.

I prototyped doing it using existing command line tools, something like:

    playdv --dump-frames=- --audio-file=foo.wav foo_ntsc.dv | \
      ppmqscale 720 576 | \
      encodedv stdin foo.wav > foo_pal.dv

Which sort of worked. I didn't get the audio stream, and I had to tweak
encodedv because I couldn't make it understand "-" for stdin (hence
"stdin"
above).  Also ppmqscale crashed on the above arguments on a zero-divide
(a
comparison on width was causing it to call shrink_picture() instead of 
enlarge_picture()).   I still need to drop every sixth frame, too.  But
it shows me that the necessary pieces are there.

When I get the audio stream figured out (yeah, I could do it with a
second
pass using encodedv, I'd rather not), I'll let you all know.  I may end
up
just rolling the relevant parts of all the above programs into a single
ntsc2pal program.  (PAL to NTSC would be similar to above but with
different
arguments to ppmqscale, and probably duplicating every 5th frame.  Not
real
pretty, I'm afraid.)

If anyone wants the specific changes to ppmqscale and encodedv I
mentioned
above, let me know and I'll post the diffs.

-- Alastair