Re: [transcode-users] smoothing out sharp edges

[Phil Ehrens <phil@xxxxxxxx>]

Carl Karsten wrote:
> Eric Lavarde - ASB wrote:
> >Hi,
> >
> >>I have a mp3 podcast that was done with a crappy mike or something - it
> >>has a
> >>lot of high end twang - is there a filer I can use to make it "better" ?
> >>
> >>even just shifting the freq of everything down a bit would be a help.  it
> >>is
> >>currently like listening to nails on a chalkboard.
> >If it's audio only, have you tried with audacity (GUI) or sox (command 
> >line)?
> 
> Nope.  unless you think they will give me better results, I would rather 
> use transcode - I already know a bit about it, and it seems like something 
> worth learning more about.

Well, frankly, Transcode would do well to encapsulate sox as a
module, since it is "the right thing". Basically, sox contains the
accumulated knowlege of the free software audio processing
community.

As the sox webpage says:

The following effects can be applied to sound data (using sox):

    * Channel averaging, duplication, and removal
    * Band-pass filter
    * Band-reject filter
    * Compress and Expand (compand) the dynamic range of samples
    * Chorus effect
    * DCShift audio
    * Deemphases filter
    * Move soundstage to front of listener.
    * Add an echo or sequence of echos
    * Fade in or out
    * Apply a flanger effect
    * Apply a high-pass filter
    * Apply a low-pass filter
    * Display a list of loops in a file
    * Add masking noise to a signal
    * Multi-band Compander
    * Pan sound between channels
    * Apply a phaser effect
    * Change the pitch of a sound file without affecting its speed.
    * Change sampling rates using several different algorithms.
    * Repeat audio data
    * Apply a reverb effect
    * Reverse sound samples (to search for Satanic messages :)
    * Detect periods of silence and start and stop processing based on it
    * Change the speed of samples being played (without affecting pitch)
    * Display general stats on sound samples
    * Stretch/shorten the duration of a sound file.
    * Swap stereo channels
    * Create sounds with a simple synthesizer
    * Trim audio data from beginning and end of file.
    * Add the world-famous Fender Vibro-Champ effect
    * Adjust volume of samples.