To increase the space for the video and at the same time increase the audio quality you can also encode your sound to a vbr-mp3 (variable bitrate) or an ogg vorbis audio file. This does not work for mpeg1 (VCD) and mpeg2 though (CVD, SVCD, DVD).
Audio Track
To accomplish this you have to extract the audio to a separate file after you've cut the video but before compression. Just choose File -> save WAV in VirtualDub(Mod) and specify the path and filename. This will save your audio content to a separate file you can then modify.
Now you can denoise the audio track or use any other filters in your favourite audio editing program. This will not be treated here though.
To encode the audio file we are going to use BeSweet by DSPguru You can download it at Doom9 in the Software section. Download both the .exe file and the GUI as you probably don't want to run the process by commandline :-), and extract both to the same folder.
Now run the GUI. The following window will appear:
First you have to set the paths of the audio files, both the one you
already have and the one you want. Do this in the "Locations" corner
(upper left).
Specifiy the location of "BeSweet.exe":
Choose "BeSweet.exe" and hit OK.
The same should be done with the Input file (extracted WAV file) and the Output file (either mp3 or ogg).
OGG-Vorbis:The audio has very high quality and the filesize of your final audio gets a little smaller than with mp3, therefore you have more space for the video. Another advantage is that the ogg format is completey free, developed by Tobias Waldvogel, which you cannot say about the Frauenhofer mp3 codec. The resulting file, an ogm and not avi movie file cannot be processed as easy as possible (AFIAK this is now possible to at least some extent with VirtualDubMod - see doom9.org for details!) and you have to install the Ogg Vorbis Playback filter.
MP3-Format: Very high quality (like ogg vorbis in variable bitrate),
but the files are a little bigger. The advantage is that you can easily
process the resulting avi file in Nandub and you do not need to install
separate filters. I think I can assume that mp3 are supported on virtually
every PC right now.
Please remember that it is not the best idea to put vbr mp3 in avis.
This is a hack not supported by every program and you may get problems
when seeking through or editing the video. I did many avis including vbr
mp3 and did not have such ugly problems, but to make sure, please take
a look at the OGM container where you can also put in vbr mp3, if you like
to.
If you are working with BeSweet for the first time the amount of options can be overwhelming. Fortunately DSPGuru has already prepared some profiles which will do all the setup for you and result in almost perfect quality.
Simply choose the profile you want under "BeSweet-Profiles" (double
click).
For MP3 I'm going to use "DSPguru_44.1Khz_MP3@128kbps", for Ogg "DSPguru_OGG@90kbps".
Now just hit "Wav to OGG" or "WAV to MP3" and the process is started: this will take a while.
Video part
Now of course we have to (re)calculate the right bitrate. Therefore we are going to look at the file size of the final audio and enter it in the Excel spreadsheet (Size of the audio in MB) or in another external bitrate calculator. Then just enter the length of the film and you'll have the appropriate bitrate.
Attention: If you exit your Excel file with "save" the original file is overwritten and the "normal" bitrate calculation will not work afterwards. Don't do it!
Please also make sure to leave enough space for the "Frame-Overhead" (7MB should be sufficient)
Now proceed as described in the guide. Just make sure that "Audio -> No Audio" is also checked for the second pass.
Compression (disregard the
audio section!)
Multiplexing (Muxing)
After quite some time the video compression will finish and you can then proceed with rejoining (muxing) the audio and video. This is a different process depending on which method (ogg or mp3) you chose.
Ogg: Well as I (the translator) am under
quite some time pressure and these steps have been very well explained
by doom9 I'm just going to give you the link to the appropriate doom9 Guide.
Note that this is a full ogg guide so the section important to you will
only be the last one! (Step 4)
Doom9's ogg mediastream guide
MP3 Again, as I (the translator) am under
quite some time pressure and this has been very well explained by doom9
I'm just going to give you the link to the appropriate doom9 Guide. It
is far more comprehensive and also more likely to be updated frequently.
Doom9's
mp3 muxing guide
Now you are all done and can play back the video in your favourite player. The only step left is splitting, if you did go for more than one CD.
(optional next step; <Improving playback quality> )
(optional next step: <Audioproblems> )
Next step: Appendix: <NEXT>
Back to the Index: <HOME>
Last edited on: 09/11/2003 | First release: n/a | Author: BaronVlad | Translator: SteVe (killingspree) | Content by Doom9.org