Question of Render File Size and DVDA

Denicio wrote on 8/30/2010, 8:37 AM
OK, i am trying to author a DVD and running into some large file sizes, so i've tried a couple of things but get stumped.......... so HERE is the question and situation.
I am authoring an MMA fight video that i have shot. Rendered as MPG-2 its 809KB, rendered as MPG-1 its 178KB... BUT when i put the videos in DVDA the 809KB becomes 875KB but the MPG-1 goes from actual file size of 178KB to 1.1gig. WHAT is happening here? I am trying to reduce the file size so i can get 11 fights on one DVD. I was takign the larger fights and looking for an alternative way to render them in Vegas to get smaller file sizes. I thought the MPG-1 would do it, but somehow DVDA makes the file HUGE. What on earth am i missing here?
Also, any suggestions on making the files smaller?

Thanks for ANY and ALL help with this.
Dennis in Memphis

Comments

musicvid10 wrote on 8/30/2010, 8:54 AM
-- You want to render MPEG-2 for DVD, not MPEG-1.
-- You must take into account overhead and conversion. That's why you need to use a bitrate calculator.
http://www.videohelp.com/calc.htm
-- DVDA overestimates space use. If the calculator says you are safe, go ahead and prepare the DVD, and see what size it comes out.

There is something very wrong with your math.
875 KB x 11 = .009 GB
A DVD5 disc holds about 4.35 GB of video

For instance, 11 segments on one disc comes out to about 400 MB (Megabytes) each.

You also did not state the length of your segments.
Length x Bitrate = File Size
Denicio wrote on 8/30/2010, 9:38 AM
Sorry, yeah i do see where i was shy with some info.

There are 11 fights total. I dont have the full sizes in front of me now, but when i added all of the fights (MPG2 renders) to DVDA it showed that i had about 5.3 gig of info and it would not let me crunch it any further (slider bar).
So i went after 2 of the larger fights hoping to crush them down to get it to fit.
I thought the MPG1 would do it, but DVDA seems hell bent on making a small file HUGE (as there a reason it does this, BTW?). I guess i am gonna have to go back to rendering in MPG2 as you suggest and just adjust some of the bitrate settings for the renders.
The audio on these fights is not all that great, its camera mic audio from some low level prosumer sony cameras, and its really just ambient noise, so if i can really cheat anywhere..the audio would be the place.

Any suggestions on where i should look to change the settings to still get useable video/audio.

Here is a link to a 'Fight Promo" i did last week. It was my VERY 1st Promo of its kind. Kind stole the format from the UFC. I made a TON of mistakes, but have learned from them. Next promo will be better.



Thanks again for helping me understand this rendering stuff as it relates to DVDA

Dennis
Chienworks wrote on 8/30/2010, 9:47 AM
It looks like you're still not taking bitrates into account at all.

When you give DVDA a file of any type other than MPEG2 it has to convert it to MPEG2, and it will do so at about 6Mbps. This gives you room for about 95 minutes on the disc. What you need to do is add up the length of all the fights and calculate the necessary bitrate to get them all to fit on the disc. A very handy rule is to divide 600 by the length in minutes and use this for Mbps. So, if all your fights add up to 120 minutes then you would need a maximum bitrate of about 5Mbps. Leave some room for audio, menus, and other overhead and the video will have to be about 4.75Mbps.

Without taking bitrates and the length into account, statements like "the original files are about 5.3GB" doesn't mean much.
musicvid10 wrote on 8/30/2010, 9:49 AM
You will set your Custom MPEG-2 bitrate in Vegas to give you the output file size you wish, after having determined that using the bitrate calculator.

Again, how long is the video?

Length x Bitrate = File Size

You wil want to use the correct DVD Architect template for the video, and the AC-3 DVD template for the audio, to avoid DVDA rendering your material again.
Denicio wrote on 8/30/2010, 12:50 PM
ALL of this is really good stuff. Thanks guys for helping me thru this.

The 600 / length of clips is a biggie! Before it was just a spitball guess at best.

Thanks for the tips!

Dennis
rs170a wrote on 8/30/2010, 2:58 PM
http://www.johncline.com/bitcalc110.zip

Mike