-/*
- * Warning: when encoding, at least 4 bytes of extra space are needed.
- * Better use this macro to calculate buffer size.
+/**
+ * Encodes @len bytes of data pointed to by @src by base224 encoding.
+ * Stores them in @dest and returns the number of bytes the output
+ * takes.
+ */
+uint base224_encode(byte *dest, const byte *src, uint len);
+/**
+ * Decodes @len bytes of data pointed to by @src from base224 encoding.
+ * All invalid characters are ignored. The result is stored into @dest
+ * and length of the result is returned.
+ */
+uint base224_decode(byte *dest, const byte *src, uint len);
+
+/**
+ * Use this macro to calculate @base224_encode() output buffer size.
+ * It can happen 4 more bytes would be needed, this macro takes care
+ * of that.