View Full Version : Bitrate Calculate.. too big ?!
BlacKRaiN
27 May 2002, 11:21 PM
Hey !! I used flakmpeg to do my dvd - divx convertion.. and as for the Divx bitrate I used 602 kps .. wich my calculator gave me as a perfect fit for 1 700 Mb cd... yet my final movie is 798 mb :| !! How come ?!
The quality is nice thought... sound perfect (mp3 128) video nice (23 fds, 720/400) 134 Minutes
Please help :)
UncasMS
27 May 2002, 11:43 PM
thats just the way a codec 'behaves'
take a look at guides like nickys
(can be found in the VERY TOPMOST posting in this board)
BlacKRaiN
27 May 2002, 11:58 PM
But then.. how do I anticipate the end size of my newly compressed dvd to divx movie ?! :P
Originally posted by BlacKRaiN
sound perfect (mp3 128) video nice (23 fds, 720/400) 134 Minutes
wow, that's like 0.089 bits per pixel, you should go for 2 CD's or reduce the res to something like 512*288.
Which codec did you use, and did you use 1 pass or 2 pass encoding ?.
BlacKRaiN
28 May 2002, 12:19 AM
Used Divx 5.0 Pro
I'm guessing 1 pass :P I just did.. Flak it.. and voila (once) so.. 1 pass !! And if I do it on 2 cd's.. how much kbps should I use ?!
Which calculator should I use to really get the perfect bitrate to get the real final size ?! etc ?! :P Thankx
BlacKRaiN
28 May 2002, 02:11 AM
Okay so... everytime I calc in Divx Calculators.. it tells me 585 kbps...to fit in 700 MB.. but I did it with 602 and that gave me 790 MB... anyway before I Flakmpeg it to know really how many megs am I gonna end up with ?!
And like I said earlier.. is there any way to really got the appropriate kbps for my movie easily to have great quality ?! (i.e. when to do it on 2 cd's.. of if only one is okay... etc)
Well some bitrate calculator, might give slightly differing results, because they calculate the avi file overhead differently.
According to GKnot the bitrate should be 598.
585 kbs sounds like you are calculating for divx3 (divx3 uses 1kbs = 1024 bit, divx4/5 uses 1kbs = 1000 bits).
But to get more precise filesize prediction you must use 2 pass encoding. To do that you must first encode with '2-pass first pass' and then encode again with '2-pass second pass'.
BlacKRaiN
28 May 2002, 02:46 AM
Ohhh :) So the trick is 2 pass... does that change quality ?!
How to we do that using Flakmpeg ?! Should I use another software ?! :)
Originally posted by BlacKRaiN
Ohhh :) So the trick is 2 pass... does that change quality ?!
Overall 2-pass encoding should produce better quality at the same filesize.
Originally posted by BlacKRaiN
How to we do that using Flakmpeg ?!
I just told you: you must first encode with '2-pass first pass' and then encode again with '2-pass second pass'. (see attatchment)
Originally posted by BlacKRaiN
Should I use another software ?! :)
GordainKnot is a nice tool for DVD->Divx conversion, but ofcause the choice is yours.
Checkout the GKnot divx5 guide at www.doom9.net
BlacKRaiN
28 May 2002, 03:35 AM
Sorry again :angelgrn:
But hurm.. you said same Filesize ?! Really... didn't you say earlier that 2 pass would give me a smaller filesize..well closer to the one I got using the calculator ?!
But to get more precise filesize prediction you must use 2 pass encoding
Overall 2-pass encoding should produce better quality at the same filesize
??? Dont :smashead: me :) lol.. thanx really for everything !!!
You are ofcause correct in saying that 1-pass encoding might produce better quality than 2-pass encoding at the same bitrate setting, because the one pass encoder might cheat by producing a much bigger file than the 2-pass encoder.
This is exactly why I said filesize, comparing the quality of 2 different encodes based on the bitrate setting is not really usefull, unless both methods can be trusted to produce accurate filesize.
BlacKRaiN
28 May 2002, 07:26 AM
Hummmm nice :) I read alot about GKnot... love it .. but one tiny problem.. I don't seem to find any wayz to do "2-pass" movies with this product.. help please :) How do I do them.. I do how to do 1 pass no problem.. but 2 ?! :| !!
GordianKnot will automatically do 2-pass encoding, it can't do 1-pass.
BlacKRaiN
28 May 2002, 07:54 AM
Ohhhhh.....
:eek: I look stupid now :D :rolleyes:
BlacKRaiN
28 May 2002, 09:17 PM
Hurm... I eel shy asking another question.. but here it goes...
I tried GKNot... liked it exactp fr the sound part.. I demuxed my ac3 more then once to be sure... so i'm sure the ac3 is fine, but when it come to converting it into mp3 using BeSweet like the guide says so.. I get thrre CRC Errors real quick.. so I get 126 K of Mp3... and my sound doesn't work... any solutions to this or help I could get ?! :) thanx !!
BlacKRaiN
28 May 2002, 09:23 PM
Also... while I'm at it....
Say I extract the sound using vob2audio.. then to wav... then to mp3... how can I tell GKNot to use THAT mp3 in the final encoding.. can I ?!
I tried GKNot... liked it exactp fr the sound part.. I demuxed my ac3 more then once to be sure... so i'm sure the ac3 is fine, but when it come to converting it into mp3 using BeSweet like the guide says so.. I get thrre CRC Errors real quick.. so I get 126 K of Mp3... and my sound doesn't work... any solutions to this or help I could get ?! thanx !!
Hmmm... strange
Try putting the latest version of Besweet in your GKnot folder
http://dspguru.doom9.net/
Originally posted by BlacKRaiN
Also... while I'm at it....
Say I extract the sound using vob2audio.. then to wav... then to mp3... how can I tell GKNot to use THAT mp3 in the final encoding.. can I ?!
Yes that is easy, instead of selecting an ac3 file and setting the mp3 conversion, just select the mp3 file and select 'just mux' in the encoding control panel.
SuperPutaMierda
28 May 2002, 09:48 PM
I extract the audio using GraphEdit (about 15 minutes) and then use Nandub to multiples (about 1 hour) and thatīs it, perfect!!
BlacKRaiN
28 May 2002, 11:58 PM
Nice :) khp thanx for all help :)
Last final request.. what proggy should I use to convert my wav (given by vob2audio) into mp3 ?! I have MusicMatch JukeBox 7.1... would that do the job ?
I would suggest using lame.
http://www.doom9.org/software2.htm#audio
BlacKRaiN
29 May 2002, 02:16 AM
There's a Lame inside vob2audio... should I go directly from Ac3 to Mp3 using vob2audio.. or use vob2audio to get a Wav file. then use Lame seperatly to get my mp3 ?! :)
Unless you need to do some filtering, that isn't supported by vob2audio, there is no reason to convert to wav, before encoding with lame. But ofcause I have no experience vob2audio.
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