Is a 4.40GB MPEG-2 file too big to render to DVD?

jayhink wrote on 6/16/2009, 5:44 PM
Hi all-

I've recently shot an event using progressive 24P and edited in Vegas 8 using the 24fps property setting. The end result is two halves of the show to be put onto a double-disc DVD set. However, the disc 2 mpeg file is 4.4GB. When I put it into DVD Architect it says it is too big for the 4.7GBGB disc.

The actual video clocks in at 1 hour, 40 minutes.

Part 1 is smaller at 4.14GB. I haven't tried to render a DVD of it yet. I suppose I can rerender in Vegas with a different 'split' point to make the one side a bit smaller. I just wanted to ask first to see why the 4.4GB won't fit on a 4.7GB disc.

Thank you in advance.

Comments

Chienworks wrote on 6/16/2009, 6:09 PM
It depends on who's defining the gigabyte. Some define it as 1000^3, and others as 1024^3. The 4.7GB usually ascribed to DVDs is the first type, so it's 4,700,000,000 bytes. The 4.4GB of the file size is the second type, so it's 4,724,464,026 bytes.

We usually say that a 4.3GB file is the maximum size that will fit on a 4.7GB disc.
Tim L wrote on 6/16/2009, 6:17 PM
What format did you use for audio? If you used PCM you can save some space on the DVD by changing that to AC3 any maybe avoid re-rendering the video.
jayhink wrote on 6/16/2009, 9:47 PM
Thanks for the replies.

How do I discern which audio I have used? In the template I am using, these are the settings:

Audio Mode: Stereo Mode
Psychoacoustic Mode: Psychoacoustic Model 2
Audio Layer: Audio Layer 2
Bit Rate (kbps): 224
Emphasis: No emphasis (default)
Sample rate (Hz): 48,000

I'm not very knowledgeable with customizing the specs beyond what the templates are. Is there anything in the audio settings I should change to try it?

As for the file sizes, here is what the computer is reading:
Disc 1 mpeg-2: 4,447,660,032 bytes
Disc 2 mpeg-2: 4,565,602,304 bytes

These are still giving me the "too large" message in DVD Architect.
Chienworks wrote on 6/17/2009, 3:56 AM
When you rendered the audio you chose a file type, either .wav or .ac3. From the template settings shown you must have chosen .ac3, since .wav doesn't have a bitrate as such.

Note that the audio file has size too, so you should be adding that to the mpeg2 file size to get the total. Your video file sizes are so close to the limit that there might not be enough room for the audio as well.

Also, DVDs have some overhead for other files, even if you don't include menus. If you do include menus then these take up space too.

All that aside, go ahead and try preparing to see what happens. DVDA is nortorious about complaining that content won't fit even when it's well under the limit. If the prepare step works then try burning to a DVD-RW and see if it works. You might just get lucky.

If not, then you should create new .mpg files with a slightly lower average bitrate. Dropping it even 5% will make your files 200MB smaller which should give you plenty of room and not be significantly lower quality. There's also a program called 'dvdshrink' which purports to reduce the size of already rendered DVD files with no quality loss at all.
jayhink wrote on 6/17/2009, 5:16 PM
Thanks for your expertise, Chienworks.

I've set the system to re-render the file again, dropping the average bitrate setting from 6,000,000 to 5,700,000 (5% lower). We'll see how that works out!

The funny part is that I've never had such trouble squeezing 2 hours of video on to a DVD in my 5 years of doing this type of stuff. (always with DVD Architect as well). Good learning experience I guess.
musicvid10 wrote on 6/17/2009, 5:27 PM
Like Kelly suggested, go ahead and ignore the warnings in DVDA and prepare the folders. You are close, but it might fit.

There is a great bitrate calculator here:
http://www.videohelp.com/calc.htm

Usually, to fit 2 hours on a standard disc, you need the average bitrate down to around 4.5Mbs, more or less depending on the amount of menu and introductory material you have.
jayhink wrote on 7/13/2009, 5:19 AM
I was able to finish this project by lowering trhe average bit rate 5%, per your suggestions. I appreciate the help and just wanted to acknowledge it with a posting here on the forum.

JH
Stuart Robinson wrote on 7/13/2009, 8:15 AM
"When you rendered the audio you chose a file type, either .wav or .ac3. From the template settings shown you must have chosen .ac3, since .wav doesn't have a bitrate as such."

That's not correct; from the render settings, it looks like the OP has used MPEG-Audio, since Dolby Digital doesn't have PSM modes.

Going from 224kbs to 192kbs Dolby Digital is only going to save a little.
jayhink wrote on 7/13/2009, 9:20 AM
Interesting, Stuart. I didn't quite understand taht particular post you referred to, as I didn't remember choosing a particular type of audio. However, I thought I might have when I chose my render settings. Either way, it's definitely an MPEG-2 file, so whatever audio is rendered in such is what I had in it.

Again, thanks for the links and insight guys!
www.jasonhink.com
musicvid10 wrote on 7/13/2009, 10:43 AM
jason,
In the future, instead of rendering to one of the standard mpeg-2 templates, choose a DVDA Video Template and an AC-3 DVDA Audio Template and render separate files with the same prefix name. Then put the video file in DVDA and the audio will load automatically.

In addition to the other advantages of doing it this way, DVDA will not have to do a second render if the files indeed fit onto a single DVD, reducing your Prepare time significantly.