Problems with downconversion

[Nilfennasion]

I finally took the plunge, getting myself a JVC GZ-HD7 and shooting with it for days on end. Now, I managed to put together a DVD containing a downconverted compilation of footage from it, but that was where the problems began. Put simply, the downconversion comes out as a mess. In shots where I stand in front of the camera, the tops of my shoulders become stepped jagged lines like I used to draw on a Commodore 64. Grass shimmers when the camera really is not moving at all. In short, it reminds me of every reason why I wanted to leave SD behind.

Problem is, I have friends and family I am making these discs for who still have CRT televisions that cannot display a high-definition signal. That, and the fact that I do not yet have Blu-Ray burning capability, means that simply duplicating the original HD material is not presently an option. I am stuck for ideas on what to do about this. The software I am presently using to create the downconverted DVDs is the Cyberlink BD Solution package that is included with the GZ-HD7. Am I doing something wrong in order to produce this effect? Is there software that will produce a less jagged picture? What can I do?

[yoda313]

Is that possibly from converting interlace material? I don't know for sure but if it was shot in interlace keep it interlace.

Also you have a few high def options.

You could convert to high def computer codecs like h264 or high def divx and send to them that way. However they would most likely be able to only play back on a computer. But it should probably look better than sd material.

Another option is to put less material on the disc and use a higher bitrate. Instead of putting an hour on the dvd maybe put a half hour and try upping the bitrate. Though remeber not to go over 9000 as some dvd players can't handle that high of a bitrate and is essentially beyond the specifications.

Also - remember you can't make hd look perfect in a downconversion. You are removing detail to compress to a different format. That is the nature of compression.

But like I said try putting less video on the dvd and raising the bitrate and you might have better results. Also if you shot in progressive mode keep it in progressive mode and vice versa for interlaced.

[Nilfennasion]

Clarifying a bit...

The problem is definitely not compression artefacting. There is a little less than 55 minutes of material on the disc so far, in fact. Originally, the software stated this would require 3.8 gigabytes of disc space but instead gave me a 2.94 gigabyte image. So I am a bit suspicious of the program(s) in question already.

The only thing I can think of that would be causing this much grief is that I am setting the programs to create an NTSC disc when the material was shot in PAL. The interlacing is retained and the material is otherwise of good quality. The problem really is that for the individual I am making the disc for, sending the results in PAL is not an option (damn Americans :P ).

[yoda313]

Ahh that is the problem than. Pal-ntsc conversion is an issue.

HOWEVER one quick issue would be to simply send them the pal disc and have them play it on a computer. They don't have format restrictions and since it is a home made disc it won't have a region lock issue. They may also be able to use a hack to get their normal dvd player to play pal discs.

The only other thing you can do is to go through the entire conversion process from pal to ntsc. You have a 25fps video that needs to be converted to 29.97fps (some apps may require 30fps check your specification).

There are plenty of guides to do it on this site. Just search for pal to ntsc.

[Nilfennasion]

So, to clarify here...

What you seem to be saying is that I should make the disc in PAL, convert it to NTSC, then burn it to a disc. Would I be correct in assuming that? (Just for the record, whenever I make a DVD, I always encode it into a directory or disc image on my hard drive first, so a bit of multi-program fiddling will not be a problem.)

Also, the person I am sending the disc to is a bit of a Luddite. She still uses AOL from a computer that she does not even know how to check the specs of but runs Windoze 98, so I doubt computer playback is an option in this case.

[yoda313]

Ok so forget the keep in pal option then if your friend isn't tech savvy. That might be trouble than its worth.

You don't have to author the disc in pal and then do the conversion. You only need to make the disc in pal if you want to keep your own personal copy. But even then you can do the conversion straight from your original source material. That in the end will provide better results.