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theReal
26th June 2004, 12:10
Adobe Encore DVD 1.01 doesn't have a bitrate calculator - instead in the manual it gives you the numbers how to calculate the bitrate... of course I could do that, but then I'd always have to look it up again when I'm authoring a DVD once in two months.

Well, I'm lazy, and I'd like to have a calc program that gives me the right DVD MPEG2 bitrate when I enter the length of the source file.
I found tons of calculators that will calculate MPEG4 bitrates, but none for DVD MPEG2 - there must be something like that available, just I couldn't find it because all those MPEG4 calculators were jamming up my google results (unfortunately most authors call their progs "dvd bitrate calculator" although they are MPEG4 bitrate calculators...)

Crazyjoe
26th June 2004, 15:07
What about the bitratecalculator in the downloadssection of doom9? :confused:

theReal
26th June 2004, 15:27
Hmmm, I'm pretty sure I had a look at that before (I wouldn't skip dooms download section when in search for video tools)
I guess the "number of CDs" tab made me to think this is a divx only calculator and so I haven't had a closer look...

I think it will do the job - thanks for pointing me to the most obvious :D


*edit* I found version 1.0 of BBC in my downloads folder (means I had d/l'ed and opened it) but the description of version 1.0 goes
This program will calculate the bitrate to use when encoding a DivX video. So I probably just read that and put it aside...

Crazyjoe
26th June 2004, 15:31
Yeah, the "number of CDs" section made me a little confused in the first time. But since then it did quite a good job. :)

theReal
26th June 2004, 15:46
btw. I find it's pretty poor from Adobe to not include a decent calculator in their program. I mean it's a pretty expensive piece of software and all it offers for bitrate calculation is an example like this:

Bit budgeting for a 120-minute video with three audio tracks, two subtitle tracks, two motion menus, and a one-minute movie preview to be burned to an 8.54 GB disc proceeds as follows:

Calculate the total available disc space in bits. An 8.54 GB (gigabyte) disc contains 8,540,000,000 bytes; each byte contains 8 bits. 8,540,000,000 x 8 = 68,320,000,000 bits = 68,320 Mbits.
Calculate the disc space available for video. Combine the size of the audio, subtitles, motion menus, movie preview and 4% of the disc capacity (for overhead, just to be safe) and then subtract that sum from the total available space you calculated in step 1.
Three 120-minute audio streams, two with a data rate of 0.192 Mbps and one with a rate of 0.448 Mbps: (2 x (120 min. x 60 sec/min x 0.192 Mbps) + (120 min x 60 sec/min x 0.448 Mbps) = 5,990.4 Mbits.
Two subtitles with a data rate of 0.010 Mbps: 2 x (120 min x 60 secs/min) x 0.010 Mbps = 144 Mbits.
Two 24-second motion menus with an estimated data rate of 8 Mbps: 2 x (24 sec x 8 Mbps) = 384 Mbits.
One-minute movie preview with a data rate of 4.5 Mbps: 60 sec x 4.5 Mbps =270 Mbits
4% overhead: 0.04 x 68,320,000,000 bits = 2,732,800,000 bits = 2,732.8 Mbits.
Total audio, subtitles, motion menus, preview, and overhead sizes: 5,990.4 Mbits + 144 Mbits + 384 Mbits + 270 Mbits + 2,732.8 Mbits = 9,521.2 Mbits.
Disc space available for video: 68,320 Mbits - 9,521 Mbits = 58,799 Mbits.
Calculate the data rate of the video. Divide the disc space available for video that you determined in step 2 by the amount of video (in seconds) the project contains. 58,799 Mbits / (120 minutes x 60 seconds/minute) = 8.16 Mbps.
Determine the maximum video data rate. Subtract the combined audio and subtitles data rates from the maximum DVD video data rate of 9.8 Mbps: 9.8 Mbps - (0.192 + 0.192 + 0.448 + 0.010 + 0.010) = 8.95 Mbps.
So the video will fit on the disc using a data rate of 8.16 Mbps, which is below the maximum video data rate of 8.95. Further, since the target video data rate of 8.16 Mbps is above 6 Mbps, you do not need to use VBR.

P.S.: As soon as there's more audio tracks and subtitles involved, BBC won't help neither and you're back to maths again ...:rolleyes:

Inc
26th June 2004, 15:50
Try this one I made for myself as it was first purposed to be a part of my mencoder GUI "packshot" but I made that as a standalone mini appl. also.

http://home.arcor.de/packshot/bitratecalculator.exe

You can enter individual movielenghts for each video on your final DVD and also every audiotrack can have its individual kbits ... useful if for example you want encode the other language track you dont use mainly in a lower kbit or 2ch.

theReal
26th June 2004, 20:01
Thanks incredible!

drob
13th July 2004, 17:12
Incredible, I loved your little app, the cleanest and simplest interface I saw in a while, could you add an option to see the predicted sizes of the video file, the audio file and the disc size. This would help very much when using one pass vbr encodes.

Msc_Alex
14th July 2004, 16:21
Look greats and works well, no more exel sheet for me. I just miss the audio input >1000
Like with DTS and PCM, whats the unit for "overhead" MB's / kbps ?
Also if you enter a value like 45 min's audio 192 the avg Bitrate will show 4 digits but
when you click on it you will find that it is >10000.
Show it should show 10000 - 192 = 9808, and also would be nice :cool:
Show the avg Bitrate and Min bitrate ( 1000 / 0 ?) And Max Bitrate (10000- audio)
for cce !


thanks :D

Dave82
14th July 2004, 16:52
Have a look at this page (http://dvd-hq.info/Calculator.html) too... ;)

Inc
26th July 2004, 17:26
Thanks for all your advices! Ill keep them in mind and see when I get time to integrate them.


I just got back from 2weeks in Italy .. so sorry for my late reply.

:)

SiXXGuNNZ
26th July 2004, 23:22
cheap free --> http://www.videohelp.com/calc.htm

free and nice --> FitCD (http://shh.sysh.de/)

donate and ultimate --> Fit2Disc (http://shh.sysh.de/)

Pato
30th July 2004, 11:06
Try this: DVTOOL (http://www.afterdawn.com/software/video_software/video_tools/dv-tool.cfm)

It´s simple, free and complete.


But... I´m using Incredible's little app.
____
PATO