Base64 binary encode a BLOB

Question

I need to base64 binary encode a BLOB of up to 60k.
Basically I need a way to base64 binary encode a BLOB and output it to a text file.
I don't want to use UTL_ENCODE.BASE64_ENCODE(r raw) because breaking my BLOB into RAW size chunks, encoding each chunk and putting the encoded data back together again doesn't work, even if I strip the '=' character(s) off the end of all but the last chunk (they're there because of the way the data at the end of the encoded chunk falls for the bit count).
Basically I need a way to base64 binary encode a BLOB and output it to a text file.
The resultant encoded data will often exceed 32,000 characters.
Thanks in advance.
John

Answer 1

This may require a bit of tweaking for use as a Java stored procedure...
public class Base64Encoder {
/** Constructor
public Base64Encoder() {
public static String base64Encode(String s) {
ByteArrayOutputStream bOut = new ByteArrayOutputStream();
Base64OutputStream out = new Base64OutputStream(bOut);
try {
out.write(s.getBytes());
out.flush();
} catch (IOException ioe) {
//Something to do if ioe occurs
return bOut.toString();
/* BASE64 encoding encodes 3 bytes into 4 characters.
|11111122|22223333|33444444|
Each set of 6 bits is encoded according to the
toBase64 map. If the number of input bytes is not
a multiple of 3, then the last group of 4 characters
is padded with one or two = signs. Each output line
is at most 76 characters.
class Base64OutputStream extends FilterOutputStream
{  public Base64OutputStream(OutputStream out)
{  super(out);
public void write(int c) throws IOException
{  inbuf[i] = c;
i++;
if (i == 3)
{  super.write(toBase64[(inbuf[0] & 0xFC) >> 2]);
super.write(toBase64[((inbuf[0] & 0x03) << 4) |
((inbuf[1] & 0xF0) >> 4)]);
super.write(toBase64[((inbuf[1] & 0x0F) << 2) |
((inbuf[2] & 0xC0) >> 6)]);
super.write(toBase64[inbuf[2] & 0x3F]);
col += 4;
i = 0;
if (col >= 76)
{  super.write('\n');
col = 0;
public void flush() throws IOException
{  if (i == 1)
{  super.write(toBase64[(inbuf[0] & 0xFC) >> 2]);
super.write(toBase64[(inbuf[0] & 0x03) << 4]);
super.write('=');
super.write('=');
else if (i == 2)
{  super.write(toBase64[(inbuf[0] & 0xFC) >> 2]);
super.write(toBase64[((inbuf[0] & 0x03) << 4) |
((inbuf[1] & 0xF0) >> 4)]);
super.write(toBase64[(inbuf[1] & 0x0F) << 2]);
super.write('=');
private static char[] toBase64 =
{  'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
'w', 'x', 'y', 'z', '0', '1', '2', '3',
'4', '5', '6', '7', '8', '9', '+', '/'
private int col = 0;
private int i = 0;
private int[] inbuf = new int[3];
}