Ick, it's the 4:2:0 chroma sampling, I believe.  Why oh why doesn't
HDV use 4:1:1 or 4:2:2?  Does anyone know if there is any good way to
handle this?  The 1080to540 effect, as far as I can tell, does 4-row
field averaging to overcome this which doesn't sound to me to be the
best method.  Is it?

For anyone who isn't familiar with 4:2:0 chroma subsampling and interested:
http://en.wikipedia.org/wiki/4:2:0

On 2/1/07, Dan Streetman <[EMAIL PROTECTED]> wrote:
Ok, don't use that yet! :)

The color interlacing is wrong, in my tests at least.

On 1/31/07, Dan Streetman <[EMAIL PROTECTED]> wrote:
> Ok try the attached patch (i.e. apply and rebuild cinelerra) and then:
>
> 1) load HDV track (make sure track size matches HDV size, e.g. 1440x1080)
> 2) add "Frames to Fields" effect, disable "Double Fields to original height"
> 3) add "Translate" effect, use 0x0, 1440x1080 input; 360x126, 720x576 output
> 4) add "Fields to Frames" effect, disable "Fields Doubled to orginal height"
>
> that will do all the resizing/scaling in the "field domain" i.e., it
> will resize each field independently to really whatever size you want,
> and recombine them to a new interlaced frame.  The numbers in the
> translate example are what my quick calculations show for 1440x1080
> HDV and normal PAL.  This should work just as well for NTSC but with
> adjusted "Translate" Y numbers (i.e. 126->150 and 576->480).
>
> I haven't tested it yet, have to stop for the night but I'll check it
> tomorrow.  Let me know if it works for you.  I want to recheck the
> field ordering for each effect, although I think at first check they
> are right.  I also should "blank" out the unused half when not
> doubling fields.
>
> Thanks.
>
> On 1/31/07, Dan Streetman <[EMAIL PROTECTED]> wrote:
> > Oops, since I use only NTSC (480 H) I mis-spoke on the PAL dimensions.
> >  PAL is apparently actually 576!  So as far as I know you are right,
> > without a "1080 to 576" effect there is no way to convert 1080i to
> > 576i (PAL) inside cinelerra.  Either another "1080 to" effect is
> > needed or the other solution I mentioned needs to be added.  The
> > second solution I mentioned should actually be a very easy change and
> > should be generic, i.e. will accomplish 1080 to anything interlaced
> > scaling.  I will see if I can code something up today...
> >
> > As far as the "1080 to 540" effect, as I said I assumed this was for
> > PAL.  If it isn't, I have no idea what the use for this effect
> > is...the original "1080 to 480" was at least useful for people
> > converting to NTSC.
> >
> > And I agree on scripting...it can be very useful!  Sometimes though,
> > it is much harder to debug with a lot of scripting.
> >
> > On 1/31/07, Marcin Kostur <[EMAIL PROTECTED]> wrote:
> > > Dear Dan,
> > >
> > > Thanks for tips. I will try them. If they work i will make
> > > somthing like bg-render template for HDV file.
> > >
> > > [OT]
> > > Your description is also a good example how nice skripting is.
> > > If cin would be 100% scriptable, then you would just copy me you line
> > > which i would pasted in my xterm. ;-) Recenly i got involved in stupid
> > > disscussion in slashcam.de, were a guy said that because all those
> > > "long commands" linux is unacceptable. In my opinion it is windows GUI
> > > unacceptable for me because of "cliking only habit".
> > >
> > >
> > > The best
> > >
> > >       Marcin
> > >
> > > _______________________________________________
> > > Cinelerra mailing list
> > > [email protected]
> > > https://init.linpro.no/mailman/skolelinux.no/listinfo/cinelerra
> > >
> >
>
>


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