The huffman coding is used in the image compression and has nothing to do with the metadata.
If you're trying to "decode" the hex string on the page you linked, note that it's just ascii.
20 is a space.
30 is a zero.
31 is a one.
So your data is apparently:
Code:
01001110 00110100 00110000 00100000 00110001 00110100 00101110 00110111 00110001 00110000 00100000 01010111 00110111 00110101 00100000 00110011 00111001 00101110 00110000 00110111 00110001
Which, interpreted a single byte at a time (and in decimal) is:
Code:
78 52 48 32 49 52 46 55 49 48 32 87 55 53 32 51 57 46 48 55 49
Interpretting again as ascii gives:
Code:
N 4 0 1 4 . 7 1 0 W 7 5 3 9 . 0 7 1
which I believe is what you're looking for.