With Office Excel, you can sign xlsx files with pictures, and the label is < signatureimage >. POI doesn't have this feature. Can you add this feature? The corresponding contents of xmlsignatures / sig1.xml are as follows: <Object Id="idOfficeObject"><SignatureProperties><SignatureProperty Id="idOfficeV1Details" Target="#idPackageSignature"><SignatureInfoV1 xmlns="http://schemas.microsoft.com/office/2006/digsig"><SetupID>{4735669A-1C30-44D4-83AC-553F8632AF22}</SetupID><SignatureText></SignatureText><SignatureImage>AQAAAGwAAAA...AAAAA==</SignatureImage><SignatureComments></SignatureComments><WindowsVersion>10.0</WindowsVersion><OfficeVersion>16.0.13127/21</OfficeVersion><ApplicationVersion>16.0.13127</ApplicationVersion><Monitors>1</Monitors><HorizontalResolution>1920</HorizontalResolution><VerticalResolution>1080</VerticalResolution><ColorDepth>32</ColorDepth><SignatureProviderId>{000CD6A4-0000-0000-C000-000000000046}</SignatureProviderId><SignatureProviderUrl></SignatureProviderUrl><SignatureProviderDetails>29</SignatureProviderDetails><SignatureType>2</SignatureType></SignatureInfoV1></SignatureProperty></SignatureProperties></Object>
Created attachment 37479 [details] Initial version - for docx Find attached my first version I've implemented it for docx first ... as I somehow mixed it up, that you need it for xlsx :S ... but at least you can have a look at the TestSignatureInfo junit test to see how it's supposed to work. I'm trying to provide the same for xlsx soon
Added via r1882394 Seems to work with Excel. In Word, the signature image is regenerated from the plain image and this update doesn't like bitmaps. Initially I've tested it with the .emf image of a previously manual generated signature - this worked, but Office generally seems to be very picky about the dimensions used in the embedded .emf image. As this request is for .xlsx, I'm closing the ticket now. Apart of this, I had to change the way how vmldrawing parts are loaded. I've added a xsd schema, which uses a dummy namespace, which needs to be set when loading vmldrawings and the corresponding xml prefix is dropped (via XmlOption) on saving.