javascript for adding image signature with date in action wizard

I'm having trouble with adding my scanned signature into 100 PDFs in a batch.

I found the following javascript code (A) online but it's for adding "invisible signatures".

http://forums.adobe.com/thread/1169781

As discussed in the above link, I modified (A) to (B) by taking out the login part

but I don't know if putting my scanned PNG signature as appearance is correct.

After running the code, I don't see any signature on my PDF.

I don't know how to add the date and time either.

Anyone please help?

---------------------------(A)------------------------------

Sign all documents

Batch sequence name: Signature SignAll.sequ.

Task: Create an invisible signature on each of the selected files.

Example2.12 Sign all documents

/* Signature Sign All */

// Choose handler

var ppklite = security.getHandler("Adobe.PPKLite");

// Login -- change as appropriate

ppklite.login("dps017", "/C/Profiles/DPSmith.pfx");

// Add a signature field with zero dimensions (invisible)

var f = this.addField("Signature", "signature", 0, [0,0,0,0]);

// Sign it and log out. Change as appropriate

f.signatureSign(ppklite,

{ password: "dps017",

location: "San Jose, CA",

reason: "I am approving this document",

contactInfo: "dpsmith@mycompany.com",

appearance: "DPSmith"});

ppklite.logout();

----------------------------(B)-----------------------------

addField("Signature", "signature", 0, [200,200,200,200]).signatureSign({appearance: scanned_png});