signcap – Data Exchange

The functionality of the interfaces differs in some cases; each description starts by specifying which interface the method or property is valid for.

SignData property

Contains the digitised signature in SignData format.

Only available after successfully calling Capture.

object SignData

VARIANT SignData

SignDataBase64 property

Contains the digitised signature as a Base64-coded string.

Only available after successfully calling Capture.

string SignDataBase64

BSTR SignDataBase64

PadData property

For the PadTabletPC interface, the property contains the signature data in raw format as a string (null-terminated). The raw format contains the signature coordinates and the time values for them, amongst other things. For the IPadSignotecSignatureDevice interface, the property contains the SignData as a Base64-coded string.

Only available after successfully calling Capture.

object PadData

VARIANT PadData

Image property

Renders the current signature as an image (without additional biometric data). By default, the image is in TIFF format, but you can also choose a different format using SaveSignatureEx. To do this, SaveSignatureEx must be called before Capture. Depending on the format that is set, a byte array or a string is returned.

Only available after successfully calling Capture.

If the interface is used for tablet PCs, a global handle to the image is returned. After retrieval, it must be deleted from internal memory using the FreeHandle, SaveSignature, or SaveSignatureEx method. For the latter two methods, the parameter “bDeleteImage” must be set to true.

object Image

VARIANT Image

PadID property

Contains the unique identification number (ID) for the connected pad. Only available after successfully calling Capture.

string PadID

BSTR PadID

Capture method

This is used to collect signature data. A signature window is displayed on the corresponding hardware, in which the user can sign and then confirm the signature.

The signature data can then be accessed using the corresponding methods and properties.

In the event of an error (e.g., no hardware connected or incorrectly configured) or a termination (e.g., at the user’s request or due to an insufficient signature), the method returns an error code (HRESULT). In the event of serious errors, the user is informed of the type of error via a dialog box. The data structures for the signature remain empty in the event of an error.

Various image properties and pad settings can be changed before calling this method. The relevant methods are described here.

void Capture();

HRESULT Capture();

SaveSignature method

Saves the captured signature (corresponding to the Image property) as an image in the specified file.

This method can only be called after Capture has been called successfully.

The saved image is black and white (1-bit).

void SaveSignature(string bstrFileName,int bDeleteImage);

HRESULT SaveSignature(BSTR bstrFileName, long bDeleteImage);

SaveSignatureEx method

Saves the captured signature stroke (corresponding to the Image property) as an image in the specified file.
The parameter “nImgType” defines the image format in which the signature stroke is to be saved.

With this method, saving is only possible after successfully calling Capture, but it can be called for IPadSignotecSignatureDevice before Capture to set the image format.

The saved image is black and white (1-bit).

void SaveSignatureEx(
                     string bstrFilename,
                     int nImgType,
                     int bTimeStamp,
                     int bDeleteImage
                     );

HRESULT SaveSignatureEx(
                        BSTR bstrFilename,
                        int nImgType,
                        long bTimeStamp,
                        long bDeleteImage
                        );

FreeHandle method

Releases the internally stored image of the current signature. (This corresponds to the Image property.)

void FreeHandle();

HRESULT FreeHandle();