We can use ffmpeg for several purpose such as encoding.
Also we can use it to get waveform file from mp3.
This is a command for that.
ffmpeg -y -i http://ma-previews.s3.amazonaws.com/preview-251513-CSnH5LgyMq.mp3 -filter_complex “[0:a]aformat=channel_layouts=mono, compand=gain=-6, showwavespic=s=1280×720, colorkey=black, colorchannelmixer=.3:0:0:0:.6:0:0:0:.4:0:0:0[fg]; color=s=1280×720:color=#8cdbac[bg]; [bg][fg]overlay=format=rgb” -frames:v 1 ./result.png