Storing user signatures

The Gravity Payments EasyIntegrator API makes adding signature capture to your application easy. You do not have to interface with the signature capture device directly. The API handles all communications with the device including the card swiper and all user prompts.

The signature is returned at the end of a transaction as string along with the usual properties like card type, masked account number etc. You can then use the included functions to convert the string back into an image for printing or simply to display it.

• Saves signature string as a bitmap Utilities.SaveSignatureAsJPG(Signature as String, FileName as String) as Boolean
• Saves signature string as a jpeg Utilities.ShowSignature(Signature as String)
• Displays signature in a pop-up window easyIntegrator.RequestSignature as Boolean
• Prompts the customer to sign. There is no need to specifically prompt for a customer signature as part of the transaction process. The API handles that automatically. This function allows you to add signature capture to other parts of your application. ResultsFields.Signature as String
• The signature is returned as part of the normal transaction process and also after RequestSignature is called. Tip: If the Signature is empty, print 2 copies of the receipt so the customer has something to sign. ResultsFields.TransactionType as String

• ResultsFields.Signature
• Your software must be able to reprint receipts including the image of the signature along with the usual elements including the AccountCardType, Amount, MaskedAccount, TransactionType, and ApprovalNumberResult.
• The size of the string will vary depending on the complexity of the signature.

The code to run a transaction is the same as with any transaction with the device activated.

Valid transaction types include:

• CreditSale
• CreditReturn
• CreditAuth
• DebitSale
• DebitReturn

The following results must be saved in your database so receipts can be reprinted at a later date:

Acct: XXXXXXXXXXXX1008
CardType: AX
Transaction Type: CreditSale
Approval Code: 034823

I AGREE TO PAY ABOVE TOTAL AMOUNT ACCORDING TO CARD ISSUER AGREEMENT

Use either of the following functions to write the Signature string saved in your database to an image file on the hard drive.

• BMP – easyIntegrator.Utilities.SaveSignatureAsBMP(StringSavedSignature, StringFileName)
• JPG – easyIntegrator.Utilities.SaveSignatureAsJPG(StringSavedSignature, StringFileName)

This will display the saved Signature string in a popup window.
easyIntegrator.Utilities.ShowSignature(StringSavedSignature)

If you want to add the ability to capture signatures in other parts of your application use the RequestSignature function. The signature will be returned as a string in ResultsFields.Signature just like when processing a transaction.

When using the utility SaveSignatureAsBMP or SaveSignatureAsJPG, the resultant image will be 205 pixels by 83 pixels.

Depending on the signature capture device being used, the image may contain white space. The Gravity Payments software creates a canvas of 205 x 83 pixels and places the signature within the canvas. Gravity Payments will increase or decrease the size of the original image and centers it to best fit within the canvas.

The following signatures were created using a PAX MT30:

As can be seen, by the above examples, the image may vary depending on the signature. Because of this, we strongly recommend showing the entire canvas and not cropping out white space or scaling the image on a single axis (as this would create a skewed signature).

Because each signature varies, and each device has a different sized screen, there is no way to insure that a signature will fall within a specific space in the 205 x 83 Pixel canvas. Therefore we recommend (and have seen the best results with) placing the entire canvas on the screen or in print rather than cropping the canvas to fit within a specific space.

In addition, placing a border around the canvas further emphasizes that the signature was captured using an electronic means of signature capture rather than a physical means (such as a pen).