restore24 & deinterlace on PAL -> NTSC Source?

[Piper]

I occasionally capture TV shows which were initially shot in PAL (assumed) format but then later broadcast locally in NTSC. An example of this would be Coronation Street (BBC) and then rebroadcast by the CBC.

My question is, how to best deinterlace this type of source while keeping it in NTSC format?

When I step through the source, all motion areas appear interlaced. As an example, if I use KernelDeint to deinterlace the source, then motion can appear jerky at times due to the step up to 29.97fps from 25fps (I'm assuming). This seems to hold true when using a KernelBob() & BlendBob() solution as well.

Would restore24 be a good place to start with material like this? If the source was originally shot in PAL 25fps, then I'm still faced with odd framerate matching if taken down to 23fps.

Any suggestions on how to approach sources like this?

Thanks.

[Piper]

It would appear I've answered my own question here. If I wish to retain it in NTSC format, then my only option would be a general deinterlacer or a bob/blendbob() combo. Right now I'm thinking it'll be SmartDeinterlace, but that'll most likely change as soon as my latest test encode is done. ;)

Sorry for thinking aloud - any other comments welcome of course.

[manono]

What's your planned output? You haven't said, and it does make a difference. DVD, .avi, or what?

Does it have blended fields? If so, I'd go the Restore24 or RePAL route, and adjust it from there, depending on what you plan to do with it.

[Piper]

What's your planned output? You haven't said, and it does make a difference. DVD, .avi, or what?

My target is a Half D1 NTSC DVD.

Does it have blended fields? If so, I'd go the Restore24 or RePAL route, and adjust it from there, depending on what you plan to do with it.

I've yet to check for blended fields. Looks like I've a bit of revising to do in this area 7.2 Postprocessing video using AviSynth (http://www.doom9.org/index.html?/capture/postprocessing_avisynth.html).

I did run a clip through RePAL which handled it well at first glance. I also ran it through restore24 from the

restore24 revisited (http://forum.doom9.org/showthread.php?s=&threadid=75432) thread and worked with the example.avs as follows:

a2=r24kernelbob() # best blend detection, slow
b2=intellibob() # best resolution as possible gets restored,

# recommened, best, slow (a2, b2)
restore24(a2, b2)

I ended up with a very low fps value of 8.x. I'm not sure what's going on there. Does this suggest a lack of blended fields?

If I end up going the RePAL or restore24 route, I'm now looking at PAL -> NTSC conversion. Time to brush up on that process as well then! :)

[Boulder]

Using Restore24 can be quite slow so if you're going to process the clip more, it might be a good idea to save the clip to an intermediate HuffYUV AVI with only the Restore24 portions in the script and then use this clip to do the rest. I've always had to do this because R24 crashes a lot of programs, being a complex thingie;)

[Piper]

I've pieced together a script based on other posts on PAL -> NTSC conversions. What I've come up with seems to work well:

# Source is NTSC 720x480 VBLE encoded capture of converted PAL -> NTSC source

# Convert PAL -> NTSC
KernelBob(order=1,threshold=4,sharp=true,twoway=true)
ChangeFPS(59.94)
AssumeTFF()
SeparateFields.SelectEvery(4,0,3)
Weave()

# Deinterlace
KernelBob(order=1,threshold=4,sharp=true,twoway=true)
BlendBob()

This approach provides nice fluid motion, I'm impressed! (should've sought this out long ago!) My question now is, can I somehow combine blendbob in the first script block without having to call KernelBob twice? That is, convert & deinterlace in one pass? Trying to inprove speed now.

[Wilbert]

You will get even better results if you don't use VBLE for capping, because it assumes progressive YV12.

[Piper]

You will get even better results if you don't use VBLE for capping, because it assumes progressive YV12.

It assumes progressive? I missed that part, thanks for pointing that out! lol

I'm (now was) using VBLE in order to cap lossless in YV12 and to save disk space over HUFFYUV. *begins search for replacement capture codec*

[Boulder]

HuffYUV is a good choice, no need to search any further. You should capture in YUY2 anyway to avoid any problems with chroma.

[Piper]

I typically do capture using HUFFYUV for those very reasons, however I have a 4 hr capture marathon coming up and my HD will only hold so much.

[Boulder]

Then there's always MJPEG; PicVideo at Q19, if you want to tweak a bit further set luma quality to 2 and chroma to 3. I bet it'll be hard to tell the difference to HuffYUV;)

[scharfis_brain]

for PAL to NTSC conversions, you need to apply this restore24 - call as I stated in the file 'updates.txt'

1)framerate decimtation ratio is now arbitary:

restore24(analysis_clip, render_clip, int numerator, int denominator)

following ratios are practicable:

24fps blended into PAL
2997, 6250 (default, if no ratio is given)
improvement: output is no longer 24fps.
It is perfect 23.976fps

25fps blended into NTSC:
2500, 5994
this is similar to rePAL, exept that it has better blend recognition
and matches the 25fps perfect (rePAL puts out 24.975 fps)

24fps blended into NTSC:
24, 60


check for the bold italic text.

so I assume you need to call :

restore24(a2,b2,2500,5994)

for a 25 fps non-blended output

afterwards you may slow it down to 23.976 fps if you wish to create a progressive NTSC-DVD.

[Piper]

@ Boulder: Indeed, to my untrained eye at least, it was difficult to tell the difference between the two when used to capture against the same source. Thanks for the suggestion.

@ scharfis_brain: I've tried using restore24 using the following as suggested against a sample clip which I believe to be a correct source for this type of application - Keeping Up Appearances (BBC), broadcast on PBS (NTSC) captured at 29.97 fps - appears to be pure interlaced:

AVISource("c:\capture.avi").AssumeTFF()

converttoyuy2(interlaced=true)

a2=r24kernelbob()
b2=intellibob()
restore24(a2,b2,2500,5994)

If I invoke Info() after restore24, it reports 3.5251 fps. I suspected Info() wasn't reporting it correctly, so I encoded a short clip and again Info() shows 3.5251 on the resulting clip. Admittedly, I've only used the above script against this one source. Could it by my source is inappropriate? I'm intrigued with the idea of getting a resulting 23.976 progressive NTSC DVD from this source.

[scharfis_brain]

restore24(a,b,2500,5994) won't work!

read the txt-files included in the package!

you have to shorten those numbers!

2500/5994 -> /2 -> 1250/2997

restore24(a,b,1250,2997) ->this works, but:

restore24(a,b) does the same, since those values (1250,2997) are default!

[Piper]

@ scharfis_brain:

you have to shorten those numbers!

2500/5994 -> /2 -> 1250/2997

I've found the following in the updates.txt file, the same info that's posted in the Restore24 Revisited (http://forum.doom9.org/showthread.php?s=&threadid=75432&highlight=restore24) thread.

25fps blended into NTSC:
2500, 5994
this is similar to rePAL, exept that it has better blend recognition
and matches the 25fps perfect (rePAL puts out 24.975 fps)

Is there an update more recent than 2004-07-14? I can't seem to find any reference to /2 anywhere. :confused:

Regardless, I'll have a go with the defaults. Thanks.

[scharfis_brain]

oh, shit.
my mistake!

I'll update it.