How can I create a waveform image of an MP3 in Linux?

Question

Given an MP3 I would like to extract the waveform from the file into an image (.png)

Is there a package that can do what I need ?

Answer 1

I would do something like this :

• find a tool to convert mp3 to PCM, ie binary data with one 8 or 16 bit value per sample. I guess mplayer can do that

• pipe the result to a utility converting binary data to an ascii representation of the numbers in decimal format

• use gnuplot to transform this list of value into a png graph.

And voilà, the power of piping between unix tools. Now Step 2 in this list might be optionnal if gnuplot is able to read it's data from a binary format.