Hi, Can somebody tell me : how can one know what's the compression of an avi file's audio ? I came to that question as follows : About 2 weeks ago attar taught me in this forum how to increase the audio volume of various video/dvd files, including avi. As to avi files, attar pointed out that "one would have to select a compression for the new audio, else it is saved as a large, uncompressed PCM file." Now, with VirtualDub one has no choice but first to save the audio of an avi as wav, and only after that to compress that wav file(unless he doesn't mind to stay with a materialy larger file). However, I assume, that: (a)like the video component of every avi file, it's audio is also compressed; and (b)that once an audio file was compressed, it's audio quality would not improove by converting it to wav or to another less compressed form. Hence, it's important to know the kind of of audio compression of the avi (MP3, WMA - 128, 256, 320 320 - etc.). Thanks in advance stibi
If you load an avi file into VirtualDub and click File' > 'File Information', you can see the compression and sampling rate of the audio. You can also look for 'GSpot' and 'Media Info' for the same information. http://www.headbands.com/gspot/v26x/GSpot270a.zip http://mediainfo.sourceforge.net/en As you know, you can also adjust the audio volume in VirtualDub by using the 'Volume' tool in the 'Audio' menu - which also means re-compressing the audio! As to the quality of the audio - it's in the ear of the beholder. Converting and re-compressing audio has little or no effect (to my ears) on quality - and wav files often contain frequencies that only a passing Bat could appreciate.
If your converting them to DVD, most AVI transcoders like DVD Flick and ConvertX to DVD will allow you to boost the volume by as much as 50dB. Granted it does distort it but it's an easy way to boost volume ouput. If you only increase it by 20-30% you won't notice much distortion.
Hi attar and thanks for your prompt answer. Sorry, I was unable to increase the audio volume of an avi with VirtualDub as suggested by you. I loaded the avi, saved as wav. Next I opened VirtualDub, vent to Audio menu and loaded the said wav file, however, the "volume" item in the audio menu remained gray, so I could do nothing changes in that wav file. How can I overcome that problem ? Thanks in advance stibi
@stibi "As you know, you can also adjust the audio volume in VirtualDub by using the 'Volume' tool in the 'Audio' menu - which also means re-compressing the audio!" Full processing mode has to be selected under the audio menu to allow volume adjustment - which also means re-compressing the audio - else you get uncompressed (very large file size) audio. Under Video, you would choose 'Direct Stream Copy' - for the same reason.
I need some help here because when ever Ive increased the volume of an avi file using Virtualdubmod, the size of the processed avi file is massive. I increased the volume on a 1.6gb avi file before and when Virtualdubmod was finished, it was a huge 82.3GBs which is massive. Is there anyway to keep the file size more or less the same??? Any help with this will be very much appreciated
Audio > Full processing mode (which you have to select anyway, else you couldn't change the volume) then you have to select an audio compressor (select Lame MP3 if it shows up and set 48, 128, cbr, stereo). Since you are using VirtualDub Mod, 'Video' is already set for 'Direct stream copy' - which you want to keep. http://www.videohelp.com/tools/Lame-MP3
