converting PAL to NTSC question

[beammeup]

Hi.

At what point should I convert my captured PAL miniDV footage to NTSC.

I capture PAL camcorder video to the PC as PAL footage.
I use Vegas 4 to edit on the timeline and then create 1 massive AVI file
I then use TMPGenc to render that AVI to MPG2.

Should I use Vegas to render the timeline to NTSC before giving the footage to TMPGenc
OR
let TMPGenc do the PAL 2 NTSC conversion instead of Vegas ?

Which do you think is the better quality way of doing things ?

Thanks
Scott

[erratic]

TMPGEnc is a bad framerate convertor, resulting in jerky motion.
Vegas does a much better job, so render the Vegas timeline to NTSC.

I've read that Canopus ProCoder 2.0 does an even better conversion, but that's something BJ_M can tell you more about.

Anyway, I have converted PAL to NTSC with Vegas and it looked fine to me.

[beammeup]

Thanks for the info.

I'll convert to NTSC with vegas.

Will TMPGenc do a good job rendering NTSC avi to NTSC mpg2 ?

scott

[erratic]

Yes, TMPGEnc should convert NTSC AVI to MTSC MPEG-2 very well.
Same quality as PAL AVI to PAL MPEG-2 I suppose.

[bugster]

Actually, probably the best way is to take your PAL DV avi (the edited one) and load it into virtualdub. Extract the audio. Change the video framerate to 23.976fps, then save out a new copy of the avi with no audio. (or frameserve to TmpGenc)

Encode the video only to NTSC mpeg-2 with tmpgenc ensuring you set 3:2 pulldown. Use besweet to encode the audio, using the PAL to NTSC preset.

Then bring the audio and video together at the authoring stage.

[erratic]

No, Vegas will do a fine job converting interlaced PAL (25i) to interlaced NTSC (29.97i). Absolutely no need to slow the video down to 23.976 fps and then use 3:2 pulldown. That will look jerkier than the Vegas way.

[bugster]

Absolutely no need to slow the video down to 23.976 fps and then use 3:2 pulldown. That will look jerkier than the Vegas way.

I never said Vegas would not do a good job. However, your way means either generating exta frames to make it 29.976fps or losing frames to make it 23.976fps. The way I described, no frames are generated artificially nor thrown away. This means playback will be perfectly smooth. Don't diss a method you have not tried for yourself.

It is in fact comparable to the way film (24fps) is converted to PAL DVD (25fps) by the pro's, but in reverse.

If you need to keep it as avi, Vegas or some other tool that handles PAL to NTSC for DV avi would be the way to go, but as the final destination format is mpeg-2, then my solution will work at least as well if not better than using Vegas to do the conversion.

[erratic]

23.976 fps has to be progressive scan. If you slow down 25i to 23.976p you have to deinterlace the video. Then 3:2 pulldown will repeat certain fields during playback. Not entirely smooth. 25i to 29.97i with Vegas is smoother.

[bugster]

23.976 fps has to be progressive scan.

To convert from PAL to NTSC you have to resize from the height from 576 to 480. To do this properly you need to de-interlace anyway.

[The_Doman]

I have converted a few movies from my DV camcorder from PAL to NTSC with Procoder. (1.5 that is).
It has a nice PAL/NTSC frame rate converter build in which works really easy. Just choose a NTSC DVD profile in Procoder and create your MPG files.
The resulting DVD's were looking very good.

[erratic]

23.976 fps has to be progressive scan.

To convert from PAL to NTSC you have to resize from the height from 576 to 480. To do this properly you need to de-interlace anyway.

You deinterlace by separating the fields, not by blending them together into one frame. This is how you can convert PAL DV (lower field first) to NTSC (lower field first) with Avisynth:

AviSource("DV.avi")
SmoothDeinterlace(doublerate=true)
Trim(1,0)
Lanczos4Resize(720,480)
ChangeFPS(59.94) #ConvertFPS(59.94) might be smoother
SeparateFields()
SelectEvery(4,0,3) #(4,1,2) changes the field order
Weave()

If your source video is upper field first insert this command between AviSource and SmoothDeinterlace: AssumeTFF()

Vegas and ProCoder do something similar, and that's a lot better than deinterlacing by simply blending both fields together.

Slowing down PAL to 23.976p is fine if your PAL source is non-interlaced (25p).
If your PAL source is interlaced (25i) you should convert it to 29.97i the right way.

[beammeup]

Thanks everyone for their input on my question the other day

For the record, I did about an hour of captured PAL to NTSC avi using Vegas 4, then converted with TMPGenc to mpg2..... authored in TMPGenc author and the result was OK but a little too much 'Judder'

I also did a PAL to NTSC with TMPGenc, but the result was probably not as good as Vegas HOWEVER, for anyone interested !

I went out and got Procoder after 24 hours of trying to get a smooth result with Vegas & TMPGenc, and Procoder did a better job, in my opinion.

Procoder interpolates to achieve a smooth playback result, whereas Vegas seems to repeat every 5th frame to achieve the 25 fr to 30 conversion ( NOT sure if that's the official explanation, but that's the way it looks to me )

Cheers
Scott

[erratic]

Vegas does not repeat frames when it converts 25i to 29.97i. TMPGEnc does that, but Vegas certainly didn't when I tried it. I checked the result frame by frame and there were no repeated frames with Vegas. If that's what Vegas did in your case I have no idea what went wrong but it's definitely not what should happen.

[beammeup]

Yeah I appreciated your advice and Vegas did do a better job than Tmpgenc. Because I was charging a fee for the NTSC DVD's, I was being quite thorough about viewing the end result NTSC DVD

I only intended to say that Vegas appearred to repeat the 5th frame.
from a viewing observation.

After creating the NTSC DVD using Vegas, I couldn't honestly stand behind the product I was selling to the client, so I dug into my pocket reluctantly and purchased Pro coder, and the resulting transcode from PAL to NTSC was noticably better in my opinion.

I just felt that if I had posted the Vegas created NTSC DVD's to the States, I may have recieved a phone call asking about the periodical Judder effect.

I've learnt quite a bit over the last 3 days about this conversion, so that's a good thing

Thanks
Scot

[erratic]

Well, I've just converted a PAL AVI clip to NTSC DVD with Vegas 5 and ProCoder 1.5 and I can't really tell the difference. No judder in either case. I've compared several frames in both MPEG-2 files and they look almost identical. I've also done the conversion with Avisynth and the Avisynth result seems slightly sharper.

[lenti_75]

Canopus Procoder is the best for conversion between systems. hardly can tell the diference

[erratic]

And I can hardly tell the difference between Vegas and ProCoder.
But I have to add that I prefer Avisynth's conversion, and Avisynth is free.

[erratic]

Now I was able to compare: Vegas 5 - ProCoder 2 - Avisynth 2.5.5 alpha (as a frameserver for CCE).
I still didn't see much difference in judder but the Vegas picture quality was definitely the poorest of the three. Click here to see one high motion field of the three MPEG-2 files.

This is the Avisynth script I used to convert a TFF source AVI to NTSC, using Donald Graft's KernelDeint filter instead of the older SmoothDeinterlace filter (kernelbob funtion by scharfis_brain, one of the Avisynth experts in Doom9's Forum):

function kernelbob(clip a, int "th",bool "mask")
{	mask=default(mask,false)
	th=default(th,5)
	ord = getparity(a) ? 1 : 0
	f=a.kerneldeint(order=ord, sharp=true, twoway=false, threshold=th,map=mask) 
	e=a.separatefields.trim(1,0).weave.kerneldeint(order=1-ord, sharp=true, twoway=false, threshold=th,map=mask)
	interleave(f,e).assumeframebased
}

AviSource("capture.avi")
AssumeTFF()
AddBorders(8,0,8,0) # because the source file was 704x576
kernelbob()
Lanczos4Resize(720,480)
ConvertFPS(59.94)
SeparateFields()
SelectEvery(4,1,2) # (4,0,3) would change the field order to BFF
Weave()

[erratic]

UPDATE: I found a solution for Vegas. If I use the Reduce Interlace Flicker switch the result is very similar to ProCoder and Avisynth. The picture in the previous message has been updated as well. Watch it again, it now shows the same high motion field four times.