Hard Telecining my Video...

[pijetro]

Essentially, i've taken a PAL interlaced source, and have slowed it down to a Film Framerate, and deinterlaced is to a "quasi progressive" output :P ...
Since i'm exporting to tape via Premiere Pro, i need to hard telecine my source video..
I'm familiar with AVISynth and VirtualDub..
Can i use either of these tools for the job???

[vhelp]

I don't think that there is a perfect solution to this task. I'm not familiar
w/ the PAL solution, but w/ NTSC and my DV cam, I can take my 29.970 fps and
bring it down to 23.976 fps (Interlaced) using AVIsynth scripts, but will noticable
jerks. You'll lose the smoothness due to the deleted fields. Frames don't
fill in magically. Remember, each frame is two fields, and each field is a
difference pic in time. When merged into one Frame, you've got two fields
of time, in one. That's why the jerks in motion

When you convert to 59.940 (NTSC) 50 (PAL) you are taking Frames, splicing
them back into Fields, and the 29.970 (NTSC) becomes 59.940 fps of Fields.
You *could* resize each field and make it 29.970 fps, but that would prove
distortion among other issues/phenomina's.

From the video workstation of,
-vhelp

[BJ_M]

what tape will you put this on that is true progressive ?

[pijetro]

Thanx for the quick response fellas..
Merry Christmas BTW...

Essentially, this originated from a previous post.
https://www.videohelp.com/forum/viewtopic.php?t=250540

As far as DVD's go, it's easy enough to run Pulldown.exe, to create smooth playback..I've done it many times thanks to AVISynth..

I figured that it's easy enough to slow down PAL and create a film framerate out of it..
But since i'm outputting back out to Videotape, the next best thing would be to Hard Telecine..It's no different than any other Blockbuster Video, but without the expensive hardware...

Of course, this is a shot in the dark at the moment. I'm not even sure at this point if a re-render is required on the Premiere Timeline..

[vhelp]

I forgot to finsh

I'm familiar with AVISynth and VirtualDub..
Can i use either of these tools for the job???

I don't think vdub can do it, but I'm almost sure that w/
AVIsynth and the right script, it can.. most likely with
the selectEvery() command.

But, I think that you have to do it in one pass. That is,
don't bring it film, then telecine it. Rather, telecine
it w/ Film quality in the process. If you convert to a film,
and then try a telecine, you'll probably have more issues
than if you did it in one pass.

Unfortunately, I don't know how to Telecine in AVS scripts.
Least not yet.

(sorry, I wasn't finsihed, and posted too soon)
-vhelp

[manono]

Hi-

I think this will do it, using AviSynth:

SeparateFields()
SelectEvery(8, 0,1, 2,3,2, 4,5, 7,6,7)
Weave()

...and have slowed it down to a Film

I'm assumeing it's 23.976fps to begin with. If not, then add AssumeFPS(29.97) at the end of the script above. Resizing before doing this may have an effect. You didn't say if you've done that already. And I assume you also know how to handle the audio.

Another way, with the original PAL deinterlaced source, would be:

ChangeFPS(59.94)
SeparateFields()
SelectEvery(4,1,2)
Weave()

[pijetro]

Vhelp wrote:

I don't think vdub can do it, but I'm almost sure that w/
AVIsynth and the right script, it can.. most likely with
the selectEvery() command.

Yeah, i've been lurking for that..SelectEvery(),SeparateFields(),Weave() have always been a sticking point with me..
I need visual assistance, therefore can't quite comprehend the whole concept..

Manono wrote:

Another way, with the original PAL deinterlaced source, would be:

ChangeFPS(59.94)
SeparateFields()
SelectEvery(4,1,2)
Weave()

What does this accomplish??

SeparateFields()
SelectEvery(8, 0,1, 2,3,2, 4,5, 7,6,7)
Weave()

If this Hard Telecines my 23.976 framerate, then i'm off to the races...

[vhelp]

To me, a Telecine process is when you have a source that is 24 fps
and you want to Telecine it for (TV purposes) to 29.970 fps which
would mean, 3P 2I (or, 3 progressive Frames, and 2 Interlaced
Frames)

But, the problem w/ pure Interlace sources, such as DV cams, is that
you don't have true full frame pics to begin with. You have two
fields that have two motions in time (about 1/60th sec apart) and
when merged into one frame, you have a whole pic (though distorted)
because it's Interlaced.
.
Even if you could Telecine it to 29.970 fps (assuming you coverted
your DV source to 23.976 fps (or PAL equivalent) right here, your
source will be jerky.
.
Then, you want to incorporate the Telecine, which is 29.970 of
3P 2I frames. That means, it has to take out of the Progressive
(remember, it's jerky already due to the convertion down to) and
of those Progressive frames, you want to take TWO of frames and
Interlace them. Things are gonna get really ugly. If memory serves
me, I managed to do this some time ago when I too was into this
Telecine avenue of adventure I found out the hard way. But, I
think you need to, too. It won't work smoothely. That's been my
experience. I think at best, converting down to Film fps and *keep*
it in Interlaced mode might get you some bitrate quality (due to the
lesser fps to work with) But that's probably about it, not to mention
some slight jerks. (you *will* see them, after you become honest w/
yourself in the end)

But, good luck anyways, and cheers.

-vhelp

[manono]

Hi-

To me, a Telecine process is when you have a source that is 24 fps and you want to Telecine it for (TV purposes) to 29.970 fps which would mean, 3P 2I (or, 3 progressive Frames, and 2 Interlaced Frames)

That's what the first script will do. It's a pure hard telecine.

Even if you could Telecine it to 29.970 fps (assuming you coverted your DV source to 23.976 fps (or PAL equivalent) right here, your source will be jerky.

I think that pijetro deinterlaced and then slowed it down. As for whether or not it plays jerky from being deinterlaced, it kind of depends on your "threshold" of jerkiness, so-to-speak. If done with a good deinterlacer, such as TDeint, or KernelDeint, it should play pretty smoothly and look pretty good. It's academic at this point anyway, as it's been done already. But since he didn't decimate to get to 23.976, it's not as if it's missing frames or anything like that.

What does this accomplish??

I think that the script using ChangeFPS creates a progressive 29.97fps video with repeated frames. I just grabbed it from somewhere else, and didn't test it out myself. Should be easy for you to test out though.