Could you provide sample output?

[coolaj86]

Which base62 implementations is this compatible with?

Reference Strings

For reference, I believe this is what base62 encoding and decoding should look like:

Raw   : "Hello, 世界"
Base64: SGVsbG8sIOS4lueVjA (18 chars)
Base62: 1wJfrzvdbuFbL65vcS (18 chars)

Raw   : "Hello World"
Base64: SGVsbG8gV29ybGQ (15 chars)
Base62: 73XpUgyMwkGr29M (15 chars)

Raw   : [ 0, 0, 0, 0, 255, 255, 255, 255 ]
Base64: AAAAAP____8 (11 chars)
Base62: 000004gfFC3 (11 chars)

Raw   : [ 255, 255, 255, 255, 0, 0, 0, 0 ]
Base64: _____wAAAAA (11 chars)
Base62: LygHZwPV2MC (11 chars)

Reference Implementation

I generated that using https://github.com/keybase/saltpack/encoding/basex, which seems to be correct and agree with other implementations, such as https://github.com/oconnor663/basex_gmp.

package main

import (
	"encoding/base64"
	"fmt"

	"github.com/keybase/saltpack/encoding/basex"
)

func main() {
	for _, src := range [][]byte{
		[]byte("Hello, 世界"),
		[]byte("Hello World"),
		{0, 0, 0, 0, 255, 255, 255, 255},
		{255, 255, 255, 255, 0, 0, 0, 0},
	} {
		// Uses the GMP character set "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
		b62 := basex.Base62StdEncoding.EncodeToString(src)
		b64 := base64.RawURLEncoding.EncodeToString(src)

		fmt.Printf("Base64: %s (%d chars)\n", b64, len(b64))
		fmt.Printf("Base62: %s (%d chars)\n", b62, len(b62))
		fmt.Println("")
	}
}

[baztian]

Hi @coolaj86, this lib seems to produce the same results:

import io.seruco.encoding.base62.Base62;
import java.nio.charset.StandardCharsets;

class Scratch {

  public static void main(String[] args) {
    outputEncoded("Hello, 世界".getBytes(StandardCharsets.UTF_8));
    outputEncoded("Hello World".getBytes(StandardCharsets.UTF_8));
    outputEncoded(toByteArray(0, 0, 0, 0, 255, 255, 255, 255 ));
    outputEncoded(toByteArray(255, 255, 255, 255, 0, 0, 0, 0 ));
  }

  private static void outputEncoded(byte[] unencoded) {
    byte[] bytes = Base62.createInstance().encode(unencoded);
    System.out.println(new String(bytes, StandardCharsets.US_ASCII));
  }
  private static byte[] toByteArray(int... values) {
    byte[] result = new byte[values.length];
    for (int i = 0; i < values.length; i++) {
      result[i] = (byte) values[i];
    }
    return result;
  }
}

Running it produces

1wJfrzvdbuFbL65vcS
73XpUgyMwkGr29M
00004gfFC3
LygHZwPV2MC