DVD-R Questions

[dakota81]

I haven't used my DVD-R drive yet for video recording, just data files, and I thought the discs could only hold 120min of video, yet on the back label of some Sony discs I just got, the printing clearly states LP(Long Play) 240min. Is this really possible? Is there a site somewhere with information on how?

Then I also noticed today, files I write to the dvd-r I can change their priority in Nero between Low, Medium, and High. What the heck does this mean? Just curious.

 

[pitlover]

A dvd-r will hold 200 min of video burned in a manner that allows it to be played on a stand alone player.
For more than that you need AC3 encoding in your authoring software.

...And I thought that was pretty much the way it was... but I bought Kentucky Fried Movie the over day, and the fullscreen and widescreen editions were both on the same side of the DVD, equalling over 6 gigs of info. That's a nifty trick!

I have no idea on the nero options, but I don't think it encodes video DVD's unless you have a way of ripping the Video_TS folder first.

What kind of video are you planning for them? Pre-authored DVD VOB files, AVI's or MPEG2?

 

[pitlover]

My bad....
I meant 2 hours of video , not 200 minutes.

 

[icrf]

In nero, that's process priority. Every use a CDR back in the day and get lots of "buffer underrun" errors and bad discs? The computer was unable to fill the buffer in time to write, often because it was busy off doing something else. Most programs running on a computer are at "normal" priority. Setting yourself above that to burn means that you are more likely to get the CPU cycles you need. On newer, more powerful systems, this almost isn't an issue anymore, as well as with all the anti-coaster technology available.

And commercial DVDs get more than two hours (I always heard the number 133 minutes thrown about) by using multiple layers. DVD players can focus in on reading one of two layers on a DVD. In fact, almost all movies released are multi-layered because of all the extra crap directors love to throw on these things. Consumer recorders haven't gotten to the point of being able to do this yet, from media and hardware standpoints. Since they use the heating dye trick to mimick pits in actual burned discs, I imagine it doesn't translate over too well.

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...but I'm just a C man trying to see the light

 

[dakota81]

Pressed dvd's can hold 9.4gigs of data on a side, the recordable versions are limited to 4.7gig.

I thought 2 hours was the limit, but then why would Sony print that the disc can hold 4 hours? Obviously it's at reduced quality if possible, but regarless I'd like to know for sure.

 

[icrf]

The DVD spec allows for variable bitrate MPEG2 video, so I'm sure you could probably strech it even further. Does whatever software you encode the video into MPEG2 give you a bitrate option? Like maybe this LP-mode is a preset?

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...but I'm just a C man trying to see the light

 

[cdogg]

Dakota,
You might recall a recent thread:
thread602-560954

Whenever you are recording 2 hours of standard DVD quality (MPEG-2 at a constant video bitrate), it's going to take close to 4.7GB regardless if you're using DVD-R/RW or DVD+R/RW. However, the different formats have different ways of "stretching" the video out by lowering quality. As icrf mentioned, one option is a variable bitrate which is slightly less in quality. There are also lower constant bitrate settings that can stretch it even further, but with a good deal of loss in quality. The method used depends on the ability of the format ('plus' or 'minus' R/RW).

I believe DVD+R/RW has more options...




~cdogg

"The secret to creativity is knowing how to hide your sources."
- A. Einstein