The signature is used to filter files in addition to the
files extensions. This panel is used to enter that
signature into ECMerge. Many file formats have a recognizable
start with a few bytes set to particular values (e.g.
MS Windows executables all start with 'MZ' letters).
First/Last offset to test
Attempts to recognize the signature will happen at each
offset in the file between first and last offsets included,
until the signature is found.
Signature / Mask
Signature and mask are coded as a JavaScript escaped string,
each character code is used to code on bytes of the signature
(use \xhh to code non-printable values).
If the file should start with MZ followed by a zero
byte, you can write: MZ\x00
When the mask is not set, it is the equivalent of having a
string made of \xFF as long as the signature.
Then the signature is tested against arrays of bytes
starting at each position from 'first' to 'last' offsets
combined with a binary AND operation.
A helper button placed to the right of the signature and
mask fields helps you to enter scripting escape sequences.
