Is it possible to use in php?

[TopDev130]

Hi,

Recently I worked on converting mp3 to wave image.

It works well via terminal command.
Here is the code.
waveform -c#3484a6 -b#000000 -F test.wav test.png

But I have a problem to use it in php.
Here is my code.

Of course, I have tried it by considering various conditions such as full absolute path and executable directory.
I am sure it didn't work.

Here is my System Environment.
CentOS 6.9
Ruby 2.4.2p198
ffmpeg version 2.6.8
waveform 0.1.2
php 7.0.26

Is it possible to use in php?
Thanks