Getting 2 hours on a DVD?

matthew180 · Post by **matthew180** » Tue Sep 27, 2005 2:30 pm

Greetings,

I just got my copy of MSP8 and I'm trying to make a DVD ready MPEG. The video is a total of 2:03:15 which should fit on a single DVD, no? I use Create->Video and select the NTSC-DVD template which sets up:

24bits, 720x480, 29.97fps
Lower Field First
DVD-NTSC 4:3
Variable data rate, Max 8000
Audio data rate: 224 kbps

When I start to render the clip is estimated for a final size of about 7Gig, but 4Gig is the max to fit on a DVD... What am I missing? How does a commercial DVD hold widescreen movies over 2 hours long plus extras, and I can't even do a 2 hour home movie in under 7Gig?

Also, when rendering it shows the output a 1/2x. Is this just to keep the process fast? It's actually writing the whole video frame, right? It's just a little disconcerting to see that. I don't want to rener for 3 hours and have it hosed up.

Thanks,
Matthew

v2to8 · Post by **v2to8** » Tue Sep 27, 2005 2:43 pm

That's what dual layer DVDs are for, and dual layer DVD writers.

Also, 8000kbps is very high too - you will need that a lot lower to reduce the file size enough for single layer discs.

And yes, your video will render at the resolution you set - not dependant on the size of the preview window.

GeorgeW · Post by **GeorgeW** » Tue Sep 27, 2005 2:45 pm

your data rate is at 8000kbps -- too high for the amount of time you want to fit on a DVD5 disc. It needs to be closer to ~4700kbps.

matthew180 · Post by **matthew180** » Tue Sep 27, 2005 2:51 pm

Should I stay with VBR or set it to a fixed value? Also, how do I know what a good cut-off of size vs. quality? Or does that vary with every video clip? I suppose if I'm going for size then I don't have much choice do I?

I thought the dual-layer DVD's were relatively new. Or is it just the availability of consumer burners that's new? Will a standard DVD player read a dual layer disc?

Thanks,
Matthew

matthew180 · Post by **matthew180** » Tue Sep 27, 2005 2:59 pm

v2to8 wrote:And yes, your video will render at the resolution you set - not dependant on the size of the preview window.

I should have been more clear. I was referring to the window that displays during the video creation process. It has below it a box with details about how far along it is, estimated output size, completion time, etc.. It only shows 1/2 of the video frame and I thought that was something they only did in the demo/beta to cripple the output?

Matthew

v2to8 · Post by **v2to8** » Tue Sep 27, 2005 3:58 pm

I believe variable is more efficient... and no, there's not much choice if you want to get all that onto one single layer disc than reduce the quality. You may have to use trial and error to get a good quality - I've not done something that long to go on a disc - I normally go around 6000.

Regardless of the progress window size, the video will render at full frame. It's in the main versions as well as the beta/trial.

Dual layer writing (discs & drives) have only been available to consumers for a (relatively) short while.

Devil · Post by **Devil** » Tue Sep 27, 2005 4:07 pm

As a general rule, VBR is not very useful. Set video at 4000-4500 kbit/s CBR and audio at DD AC-3 2/0 192 kbit/s for a first try. If this is OK, you can try 5000 VBR and see whether you get any improvements (I doubt it). I recommend you adjust the video bitrate to get 4.1 Gb ±0.1 Gb when you go into burning.

matthew180 · Post by **matthew180** » Tue Sep 27, 2005 4:31 pm

Thanks everyone for the information!

I'm rendering the output now with 4700 VBR, which should come out to 4.381G according to the estimate. It still has 2 hours to go (58 min elapsed), but it's looking pretty acceptable if the render window is accurate to what the actual output will be like.

I'll try the CBR next time, and certainly the audio does not need to be anywhere near CD quality since the original audio is from a built-in camera mic.

Matthew

matthew180 · Post by **matthew180** » Tue Sep 27, 2005 8:23 pm

I solved my "clipping" problem in the output monitor window while rendering a video. It seems I started my project as a 16:9 format and didn't realize it. So, all my generated titles were being clipped when saving out in 4:3 format. My mistake, sorry for any confusion.

Matthew

Devil · Post by **Devil** » Wed Sep 28, 2005 6:50 am

4.381 Gby is too much. 4.377 Gby is the theoretical maximum but it is NOT good practice to fill the disk, because the outside tracks are most prone to accidental damage or manufacturing tolerance errors. That is why I recommend 4.1 Gby ±0,1 Gby as the best file size to aim for.

You may wonder how you can seem to exceed the theoretical maximum. This is probably because the value displayed is only an estimation, not an absolute figure. This is another good reason why you should not aim too high.