Dialnorm for VOBs

[Pookie]

Not mine, but I tested it out. No recoding.

Example Syntax:

Vobdnorm Input.vob Output.Vob 28

ftp://ftp.coises.com/vobdnorm-1.0.zip

[Guest]

Please tell us what this program does. Thank you.

[unskinnyboy]

There is a README.txt in the zip file which explains what it does. Also check this (http://forum.videohelp.com/viewtopic.php?p=1660216) thread from few days ago which shows how the tool originated.

In simple words, what it does is to change the dialog normalization value (dialnorm) of the AC3 stream inside a VOB container without reencoding the stream itself. AC3 decoders uses this value to determine the playback level of the stream.

Plus, maybe it's the wrong forum, since there is no audio encoding involved here?

[Pookie]

The program, VOBDNorm, copies a VOB and changes the "Dialog Normalization" value of AC-3 audio in the VOB. If the program you're using to convert the DVD to PSP video respects the dialnorm meta-data, and if the DVD has clean AC-3 audio to begin with, just a dialnorm setting that makes the volume too low for good transcoding, then running this program against each VOB ripped from the DVD before converting may help.

The link above is to a zip archive; it contains a Windows command line executable and the C++ source for the program. Just extract the vobdnorm.exe file, open a DOS window, and use a command something like this:
Code:
"path-to-exe\vobdnorm.exe" "input.vob" "output.vob" 31
on each VOB (don't make the input and output the same file!). If you see that the program says it has changed dialog normalization values of, say, 25 or less to 31, then try converting the results. (If your program converts whole DVDs, make the output files have the same names as the input files but in a different folder; then copy the other, non-VOB files into the same folder.)

(In practice, a dialog normalization value of "31" means "don't compensate for overall volume at all, just decode the AC-3 and pass it along full scale. Higher values are not possible; lower values attenuate the output by 31-dialnorm decibels. Depending on the decoder, however, compression also may be applied, and changing dialnorm can mess that up.)