decoding BLOB's

Hi All;

we've found a post about dumping blobs:
/
/

/I wrote: [fanlijing wants to write bytea to file] > A simple > COPY
(SELECT byteacol WROM mytab WHERE ...) TO 'filename' (FORMAT binary) >
should do the trick. Corrections: a) "binary" must be surrounded by
single quotes. b) *that won't dump just the binary data - you would have
to remove the first 25 bytes and the last 2 bytes...* So maybe using the
functions I mentioned would be the best way after all. You could also
write your own user defined function in C. /

Can someone point me in the right direction per how I would remove the
first 25 bytes and the last 2 bytes from a bytea column?

Thanks in advance