caculate movie size with DVD2SVCD?

[Fmazzanti]

Hi folks,
this may seem stupid, but I had a little problem here. I usually emply DVD2SVCD to extarct the audio tracks and to reencode the video of my DVD backups. Tipically I want 2 audio tracks and two subtitle streams.
Then I do the following steps:
1- Rip the whole DVD with smartripper.
2- Ectract the subtitles.
Step 2 usually takes around 0.4-0.5Gb depending on the movie. I like to author with Maestro, which I assume needs some other 0.1-0.2 extra GB. That means that I'm left with
4.35Gb - 0.5Gb - 0.1Gb = 3.75Gb
for video + audios. Then I run DVD2SVCD to do the audio extraction+video conversion, setting the CD size to 3.75 or 3.70Gb.
Would you say I'm doing it right? I ask it because sometimes I've found that, after the authoring process is done, I've run out of space to fit on the DVD-R ( sometimes the whole project has gone to 4.65Gb, out by 0.3) and sometimes the total stuff takes 3.8Gb. And always with the same amount of space dedicated to the subs... Am I missing something?
Thanks...

[markrb]

There are a couple of potential problems with your method.

1. DVD2SVCD can only figure the audio as high as 384 Kbit. This will throw off your video calculations some if your audio is 448 which I have been seeing allot of lately.

2. Previous builds had a bug that did not take into consideration the second audio track when figuring the video bitrate. Make sure you have the latest build.

I use the bitrate calculator inside DVD2SVCD to help me figure out my settings, but I always check to make sure what the audio bitrate is. Check the audio bitrate with IFOEdit first. Usually that info is right in the main movie IFO. You may have to force the Max AVG lower to compensate for the higher audio bitrate.

Mark

[idbirch2]

I found that a good way to fill your DVD but never go over is to let DVD2SVCD get as far as making the *.vaf file with CCE (the first thing CCE does when its run - the bit that takes 1-2 hours b4 actual encoding starts)and then cancel it.

Open up CCE and load the avs file DVD2SVCD made. Now right click the movie and go to setting or properties or whatever -you will see the average bitrate. Click advanced to see a VBR graph and a very accurate reading (in bytes) of how big your *.mpv file is going to be.

A DVD is 4,700,000,000 bytes so just subtract the size of your AC3 file and also subtract the size of your menu/special features VOBs and your left with an exact size available for your mpv. Just play with the average bitrate in CCE till the estimation is very close.

This is all assuming you are doing a 'proper' rip of course - if not this is all garbage.

[Calypso]

Originally posted by Fmazzanti
2- Ectract the subtitles.
Step 2 usually takes around 0.4-0.5Gb depending on the movie. Standard subtitles never take up .4-.5 GB! I always author with all subtitles, and they usually take anywhere from 5-10MB per track. Average is usually 6MB per track.

Although the bitmaps may take up that much space on your harddisk when ripping them, they encode much smaller. The best way to gauge how much space subtitles take is use VobSub, which builds an index. This index represents how much space the subs will take.

[jankster]

I don't make SVCD's I only make DVD's but it still is simple math here boys, don't need a fancy bitrate calculator. This is how I do it for DVD's:

To determine file sizes, in Explorer, right click a file and choose Properties. This will show you a file's REAL file size.

Simple example:

4700 MB on a DVD-R

-120 MB for NAV packs (this seems to be a constant)

-440.23 MB for 1-AC3 track

Leaves 4139.77 for M2V. Now use "Ac3 Delay Corrector" to find the exact number of seconds in movie (lets say its 9017.2) and use this math

4139.77 / 9017.2 * 8000 = 3672.8

Use CCE in VBR multi pass mode (I always use 2 passes) and enter 3673 for you average bitrate, set MIN=0, MAX=9000. The resulting M2V will be 4139 MB. It works perfect everytime!

[idbirch2]

All very clever apart from 1 thing: A DVD is not 4700MB.

It is 4,700,000,000 bytes. Divide by 1024 is KiloBytes and by 1024 again gives you MegaBytes. Thats 4482.27MB, so not quite sure how your maths manages to work out correct using this method, but hey, if it works....

[jankster]

idbirch2,

You are wrong. I said "right click all files and select properties to get TRUE file sizes".

Try this. I have a VIDEO_TS folder that holds a movie. Select all the files and in Explorers status bar it says 4.35 GB, almost a full disc, right? Now select all the files, right click and select properties, you get 4,673,251,328 bytes (in this example). A full DVD-R holds 4.7 GB.

1 MB = 1,048,576 bytes

[Fmazzanti]

@Calypso,
every time I rip subtitles I get some 200-300Mb of bitmaps. That's why I said I end up with approx 500Mb of subtitles. Of course this doesn't take THAT much once the DVD-R is mastered, but I didn't find an apprpriate way to estimate how much space will it take on the final product. In any case, I've seen several posts and several guides here which say that the size of subtittle will be halved, more or less, which leads to 100Mb per stream... FAAAR FAR AWAY from what you say, 5-10Mb...
@jankster,
nice maths, though I'm not sure I understand you: are you claiming that every audio track in the world is going to take 440.23Mb? Then i guess my DVD's are from outer space :D
And coul you please explain a little bit more your formula? WHat is this 9017.2*8000?
Thanks...

[jankster]

Fmazzanti

The AC3 track value was only a EXAMPLE. The 9017.2 is total movie seconds. You multiply by 8000 to to convert from mega bytes per second to kilo bits per second.

[Fmazzanti]

Fmazzanti
The AC3 track value was only a EXAMPLE. The 9017.2 is total movie seconds

Yes and you wrote it too... sorry.

You multiply by 8000 to to convert from mega bytes per second to kilo bits per second.
Uhmm...

1 (Mb/sec)*(1024Kb/1Mb)*(1024bytes/1Kb)*(8bits/1byte)*(1Kbit/1000bits) = 8388.608 Kbits/sec

which is not 8000...

[jankster]

Fmazzanti,

Tell you what, to hell with the deep thoughts, just give the formula a try. It works PERFECT everytime.

[idbirch2]

Look, I'm sorry Jankster but I aint wrong - you're just under the impression that 1GB = 1000MB - it doesn't. 1GB = 1024MB. I'm sure your maths is perfectly sound and if you swear by your mehtod I'm sure it works but quoting from 2 of your seperate posts:

4700 MB on a DVD-R

Wrong - 4482.27MB on a DVD-R

And again:

A full DVD-R holds 4.7 GB

The 4.7GB on the front of a DVD-R case is a marketing thing - its 4,700,000,000 bytes - which isn't 4.7GB

If you don't believe me try this:

http://www.malte-philipp.de/byteconverter.shtml

Select all the files and in Explorers status bar it says 4.35 GB, almost a full disc, right? Now select all the files, right click and select properties, you get 4,673,251,328 bytes

Yes you do and you'll find that what Explorer reports is actually correct - its just rounded up. 4,673,251,328 bytes is 4.3523GB with a DVD-R being 4.37722GB. Sorry.

[Fmazzanti]

Originally posted by jankster
Fmazzanti,

Tell you what, to hell with the deep thoughts, just give the formula a try. It works PERFECT everytime.

@jankster,
I'll giove it a try, but please don't be that rude... there's no need for that. We only pointed out that there are two mistakes in a single line formula, which doesn't mean that the whole thing doesn't work (errors may compensate each other, you know).Thanks anyway...

[jankster]

Fmazzanti and idbirch2

You guys are right! Your talking binary, I'm talking decimal.

1MB is "2^20 power" = 1048576. This is binary terms
1GB is "2^30 power" = 1073741824. This is binary terms

When I said:

"To determine file sizes, in Explorer, right click a file and choose Properties. This will show you a file's REAL file size."

I should have said "decimal" instead of "REAL", sorry.

My formulas are all done in decimal. The reason is to get exact values. To understand what I mean, try this: Open Notepad and enter 10 "a" characters all in a single row. Save. Now in Explorer right click/properties. It will say "(10 bytes)".

Blank DVD-R's hold 4.7GB in decimal terms.
Blank DVD-R's hold 4.3772GB in binary terms.

[Calypso]

Originally posted by Fmazzanti
@Calypso,
every time I rip subtitles I get some 200-300Mb of bitmaps. That's why I said I end up with approx 500Mb of subtitles. Of course this doesn't take THAT much once the DVD-R is mastered, but I didn't find an apprpriate way to estimate how much space will it take on the final product. In any case, I've seen several posts and several guides here which say that the size of subtittle will be halved, more or less, which leads to 100Mb per stream... FAAAR FAR AWAY from what you say, 5-10Mb...
Fmazzanti,

I have run this test many, many times. Author your DVD without, then with the subtitle track(s). You will see that the difference rarely exceeds 5-10 mb per subtitle track. There is other overhead associated with DVD authoring that other folks commonly associate with the subtitles.

The best way to determine how much space is associated with subtitles is to use DoItFast4U, which uses VobSub to extract the index of the subtitle track(s). This index file is very close to the actual space the subtitles will consume.

[waldok]

Jankster I don't get you here.

Would you please explain something : what is one GB "in decimal terms" and what is one GB in "binary terms" ? Sounds weird to me.
16 is 16 in binary terms (2^4), but what is it supposed to be in decimal according to you ? 19? 23?) ;)
To me, one GB is one GB, be it in hexadecimal, binary, decimal or "whatever-cimal" you want. :D

No big deal anyway, no offense intended, just teasing a bit. And thanks for your formula. Main point is that you say it works fine, I'll try it.

Waldok:cool:

[Fmazzanti]

Waldok, you took the words out of my mouth :p

[waldok]

Waldok, you took the words out of my mouth

Sure, and I'm pleased you didn't bite me while I was doing this :D

Buona Sera

Waldok:cool:

[FamousPerson]

Originally posted by jankster
My formulas are all done in decimal. The reason is to get exact values. To understand what I mean, try this: Open Notepad and enter 10 "a" characters all in a single row. Save. Now in Explorer right click/properties. It will say "(10 bytes)".

Blank DVD-R's hold 4.7GB in decimal terms.
Blank DVD-R's hold 4.3772GB in binary terms.
Jankster:

It may seem like you are getting exact values, but you are not. There is no such thing as "decimal terms".

If you made a notepad document with 1000 "a" chars in it, explorer would not call it a "KiloByte" - not until you had 1024 "a"'s in it.

Similarly, a Megabyte is 1048576 "a"'s, and a GigaByte is 1073741824 "a"'s. That's just how it is. If you're talking bits, divide by 8. Example: 1 kilobit is 128 "a"'s. That's 1024/8.

Now here is something interesting, though, that CCE does, which may be why your formula works:

Even though 1 Kilobit is really 1024 bits, CCE treats a "kilobit" as 1000 bits. It is important to note that this is WRONG, however, this is how CCE calculates it. So, if you enter an AVG bitrate of 3000 kilobits per second, CCE treats that as 3000000 bits per second.

[jankster]

FamousPerson,

Yes, I know a KB is 2X2X2X2X2X2X2X2X2X2 = 1024 and this is why I called it "binary", powers of 2. I know "kilo" means 1000, not 1024, this is what I was trying to explain.

In Windows Explorer, it will show you 3 different file size values for the same file. The right pane, the status bar, and "properties". Only properties gives you an exact byte count in braces. This is why I use this value. I experimented with many different values and formulas with CCE. It does not matter what or how you call it, as long as you are consistent, and get consistent results.

I took a lot of crap for "trying" to explain my method. However I have not heard back from anyone about how well it works. I was using 100 MB for my NAV pack values, but 1 out of 4 movies went over, so now I use 120 MB. When I burn my movies I fill my DVD's to the max and get the highest possible bitrate. NO GUESSING

Thanks for your reply FamousPerson