View Full Version : How to estimate post rendered file size?


Sean Seah
January 1st, 2006, 02:18 AM
Recently I made an 120min footage which rendered to 4Gb. As I was worried it cant fit on a single disk, I cut some footages but it turned out unnecessary. R we able to pre-determine the rendered mpeg2 size for rendering?

Peter Jefferson
January 1st, 2006, 02:53 AM
http://www.videohelp.com/calc.htm

Edward Troxel
January 1st, 2006, 06:48 AM
I use the bitrate chart in Vol 1 #7 of my newsletters (http://www.jetdv.com). Just vary the bitrate as needed for the length of your video and all should be fine.

Sean Seah
January 1st, 2006, 08:29 AM
So manual calculation is reqwuired but thaz better than nothing. Thanks!

Gary Kleiner
January 1st, 2006, 11:05 AM
You can only get an estimate, because files created using VBR encoding are dependant on the content of the image.
For example, if there is less variation between frames (e.g a talking head vs. a soccer game), then there is less information that needs to be encoded which results in a smaller file size.

Gary

Colin Rayner
January 2nd, 2006, 01:32 PM
Just while we are on this subject, if in DVD Arch the estimated project size is 6.3gig, yet the mpg and ac3 only add up to 3.2gig and the main title page only has 1 animation and a static scene selection, what's going on? The project is 56 min long with not alot of sound or graphic animation etc.
to get it to fit on a DVD I would have to optimize to fit quite heavily on the audio.........I have had a good read of Ed's Vol1 No7 and still can't find what's going on with this project.
Have I missed something?

Edward Troxel
January 2nd, 2006, 01:58 PM
That happens sometimes. DVDA isn't always the best at guessing the size. If you KNOW it's small enough, go ahead an prepare it ignoring the warnings. Then check the sizes of the final VIDEO_TS files to see how big the result really is. I, too, have seen it estimate double size.

Colin Rayner
January 2nd, 2006, 02:15 PM
Thanks Ed, It just didn't make sense. One more thing, the AC3 file was orphaned and I don't know why. It has a different file name than the mpeg, but it did drag and drop ok and in preview you do get the sound. After the render, the Audio TS file was empty.............

Gary Kleiner
January 2nd, 2006, 03:06 PM
The AC3 file ia automatically associated when it has the same root name and is in the same directory.

The Audio_TS folder is always empty.

Gary

Edward Troxel
January 2nd, 2006, 03:08 PM
The Audio_TS file is supposed to be empty. The audio on your DVD is included in the VOB files.