Encode base64 via atob or btoa method

[cristianghita24]

Is your feature request related to a problem? Please describe.
If a base64 encoded image using react-image-file-sizer gets sent a REST API then tried to be saved to Firebase Storage then Firebase will throw as it uses atob to decode. This issue is better described here

Describe the solution you'd like
An optional parameter to the api that specifies the encode method (i.e. atob)

Describe alternatives you've considered
I've tried using alternatives but it would mean using multiple apis as I need file conversion and resizing as well.

Additional context
Please check the stackoverflow link mentioned above.