blob64

A tiny javascript library to turn byte arrays into efficient base64 strings.

This is particularly useful with msgpack, which generates byte arrays.

blob64.pack([0,0,0])
// "0000"
blob64.pack([255,255,255])
// "////"
blob64.pack([1,3,3,7])
// "0GC31m==" 

Compared to using atob / btoa.

blob64([0,0,0])
// "MCwwLDA="
blob64([255,255,255])
// "MjU1LDI1NSwyNTU="
blob64([1,3,3,7])
// "MSwzLDMsNw=="

Usage with msgpack

var obj = {this:{is:{a:{msgpack:{object:'foo'}}}};
var packed = blob64.pack( msgpack.pack( obj ) );
// "WQHqQ6bpWQ9fSu6XOO6dRNDdS65ZQu6cRs9gPMDqesPlRm=="
msgpack.unpack( blob64.unpack( packed ) )
// {this:{is:{a:{msgpack:{object:'foo'}}}}

// vs alternatives

btoa( JSON.stringify( obj ) )
// "eyJ0aGlzIjp7ImlzIjp7ImEiOnsibXNncGFjayI6eyJvYmplY3QiOiJmb28ifX19fX0="

bota( msgpack.pack( obj ) )
// "MTI5LDE2NCwxMTYsMTA0LDEwNSwxMTUsMTI5LDE2MiwxMDUsMTE1LDEyOSwxNjEsOTcsMTI5LDE2NywxMDksMTE1LDEwMywxMTIsOTcsOTksMTA3LDEyOSwxNjYsMTExLDk4LDEwNiwxMDEsOTksMTE2LDE2MywxMDIsMTExLDExMQ=="

In the above examples, blob64 is 68% the size of JSON + btoa, the next closest competitor. This advantage increases quite a bit if your data has lots of integers in it.

Compatable with nodejs, script tag includes, and requirejs.

MIT Licence