"file" argument must be a non-empty string

[vinnitu]

$ ./index.js
child_process.js:381
    throw new TypeError('"file" argument must be a non-empty string');
    ^

TypeError: "file" argument must be a non-empty string
    at normalizeSpawnArguments (child_process.js:381:11)
    at exports.spawn (child_process.js:494:38)
    at getDataFromFFMpeg (/tmp/1/node_modules/waveform-node/waveform-node.js:47:22)
    at Object.exports.getWaveForm (/tmp/1/node_modules/waveform-node/waveform-node.js:215:2)
    at Object.<anonymous> (/tmp/1/index.js:6:10)
    at Module._compile (module.js:649:30)
    at Object.Module._extensions..js (module.js:660:10)
    at Module.load (module.js:561:32)
    at tryModuleLoad (module.js:501:12)
    at Function.Module._load (module.js:493:3)