Wrap encoded lines after COLS character (default 76). Use 0 to disable line wrapping.
When decoding, ignore non-alphabet characters.
Display this help and exit.
Output version information and exit.
With no FILE, or when FILE is -, read standard input.
The data are encoded as described for the base64 alphabet in RFC 3548. When decoding, the input may contain newlines in addition to the bytes of the formal base64 alphabet. Use --ignore-garbage to attempt to recover from any other non-alphabet bytes in the encoded stream.