Algorithm to draw waveform from audio

Question

I\'m trying to draw a waveform from a raw audio file. I demuxed/decoded an audio file using FFmpeg and I have those informations: samples buffer, the size of the samples buffer,

Answer 1

I think you are referring to a waveform described here.

http://manual.audacityteam.org/o/man/audacity_waveform.html

I have not read the whole page. But each vertical bar represents a window of waveform samples. The dark blue are the maximum positive and and minimum negative values in that window (I think). And the light blue is the RMS which is root mean squared. http://www.mathwords.com/r/root_mean_square.htm. (basically you square the values within each window, take an average, and then square root.

Hope this helps.