Conversion of 640x480/30fps to DVD: Use PAL or NTSC?

[ttn]

Hi,

I have a new digital camera capable of also shooting video at 640x480/30fps MJPEGs.
This is not as good as a DV video camera, but much more handy.

I would like to put those video clips on a DVD, either PAL or NTSC. My questions
are (note there are several):

1) What is best to make: NTSC DVD or a PAL DVD?
I live in Europa and prefers PAL, but I think both
my DVD player and TV can do NTSC->PAL conversion.

2) How do I make the needed frame-rate conversion in the best manner?
I like VirtualDub, but a direct frame rate conversion (30->25) via
"Video->Frame Rate ... " and then select 25 for "Convert to fps:" gives a jerky video.

3) Is my video source (the above *.avi files) de-interlaced?
I think so, but am not sure.

4) I have often been using TMPGEnc for MPEG-2 encoder and TMPGEnc DVD Author.
But I also like Avi2Dvd and the HCEnc as MPEG-2 encoder.
Can I do a better result than feeding my video clips directly to those tools (by
e.g. doing some frame rate conversion, resizing etc. first in virtualDub)?

Regards Torben.

[guns1inger]

a. 640 x 480 at PAR 1:1 is the same as NTSC 720 x 480

b. 30 fps is damn close to 29.97 fps (NTSC), but very difficult to convert to 25 fps without cauing jerkiness and other problems

c. Most likely your source is progressive - I know my camera does progressive at the same framerate/resolution

If you want to do a quick comparison, I would use DivxtoDVD to do a PAL and an NTSC encode of the same clip, then play them back. See which works for you. If the quality is good enough, use this to do the final conversion instead of tmpgenc. You can then load the VOBs into TDA for authoring. It is much quicker - quality will be the concern, but a short test will tell you if it is good enough.

[ttn]

Hi guns1inger,

sorry for the very late reply.

I did some testing making both a PAL DVD and an NTSC DVD. Played
both on my TV and did not see much difference.

There very jerkiness on both, but the difference was
so small that I decided to create PAL DVDs (I was
not 100% sure I could see the difference in jerkiness,
but perhaps my pre-knowledge teases me as I would
say the NTSC DVD was a little better).

And you were rigth about the interlacing. The source material from the camera
is progressive.

Thanks for your input, even though I hoped for the "world class best"
30->25 framerate conversion that is absolutely free of jerkiness .

Thanks, Torben.

[edDV]

Choice is 720x480/30p* (h-interpolated) or 720x576p/25fps** (h, v, and frame rate interpolated).

* authored as 720x480i/29.97 interlace but sample both fields from the same frame. This gives effective 30p and it will play jerky.

** softer and more jerky but PAL players will repeat frames 2x for 50Hz refresh.

[ktnwin]

I have a similar camera with same capabilities, i.e., capturing video at 640x480, 30 fps.
I always converted these video to NTSC DVD as I live in USA where all TV are NTSC.
The jerkiness actually comes from the memory card that I install in the camera.
You need to get a very high speed memory card (SD, or whatever format your camera requires) to capture MPEG-4 video at 640x480, 30 fps (mine capture at > 8000 Kbps bit rate). I see some jerkiness even with the original MPEG-4 video played in the PC itself.
When I switched to 320X240 , 30fps, the bit rate goes much lower and there is no jerkiness at all. My conclusion is I need the fastest memory card I could get ( > 120X).

This situation is very similar to capturing analog video to the PC, if the system is not fast enough or the hard drive is not fast enough, there will be skipped frames that cause jerkiness.
Flash memory is fast when reading but when it comes to writing, they are slow. It's the nature of the "cute little" beast.

[edDV]

Good point on the need for fast flash memory. My point on "jerky" was 30p and 25p will still appear somewhat motion jerky vs 29.97i or 25i which have effective motion sampling of 59.94 and 50 respectively. A tripod and 24p film shooting technique can help smooth things out. Handheld will be rough.

[ttn]

Hi,

thanks for your input. The jerkiness does not come from a "slow" flashcard
in my case (I specifically bought a fast 120x flash card for that purpose).
So I was aware of that problem. And when viewing the original material
on the PC I do not see any jerkiness.

So my conclusion is that the jerkiness comes from the 30->25 framerate conversion.
And as edDV points it the the two options I was choosing between.

Thanks for your input again, Torben.