*SOLVED* Audio LEVELER not NORMALISER

[JimW]

Isn't that the purpose of computers and this site?

To have fun and learn - and learn while having fun!
I did learn a thing or two today, thanks to Dai - and had fun doing it!

[crosscourt]

Hes a font of knowledge, lets hope that rubs off on me a bit. Ive been helping one of our members do a distro install on his older computer that went well.

[dai_trying]

@Jim
The line newgain=`echo "${mygain//[!0-9.]/}"` simply cleans the output of the $gain variable, it had a minus sign and some white-space which would mess up the next command, basically it will only leave numbers and full-stops (periods) so it can be used for the gain in ffmpeg.

And I also learn a bit along the way, as a for instance I have never needed to normalize the sound in a file, but I have some that are too quite in places and now I have the solution at my fingertips.

[chris]

You don't need the `` expression, just newgain=${mygain//[!0-9.]}
HIH

[dai_trying]

You're right, I just cut/pasted from an old script and did notice it after it was posted and probably should have edited it... Thanks for spotting it though.

[JimW]

I just tried your script out on a four minute mp4 - it works!

Something I have noticed. If there is a spike (click/pop/etc) that goes to 0db then the resulting volume is based from that and comes out lower than you might expect. When that happens I just load it into Audacity and remove the spike then amplify.

[dai_trying]

I did notice that on the test file, although it wasn't a very big difference so thought it might be ok. I guess if you are going to set it up to run automatically you are only likely to notice if the file is particularly quiet when playing it back.