Add Digital Signature to PowerPoint PPT in Python

readme.md

Learn how to add and verify digital signatures in PowerPoint PPT in Python:

add-digital-signature-ppt.py

import aspose.slides as slides

# Load presentation
with slides.Presentation("presentation.pptx") as pres:
    # Create DigitalSignature object with PFX file and PFX password 
    signature = slides.DigitalSignature("certificate.pfx", "password")

    # Comment new digital signature
    signature.comments = "Signing with Aspose.Slides"

    # Add digital signature to presentation
    pres.digital_signatures.add(signature)

    # Save presentation
    pres.save("SignedPPT.pptx", slides.export.SaveFormat.PPTX)

verify-digital-signature-ppt.py

import aspose.slides as slides

# Load presentation
with slides.Presentation("presentation.pptx") as pres:
    if len(pres.digital_signatures) > 0:
        allSignaturesAreValid = True
        print("Signatures used to sign the presentation: ")

        # Check if all digital signatures are valid
        for signature in pres.digital_signatures :
            print(signature.certificate.subject_name.name + ", "
                    + signature.sign_time.strftime("yyyy-MM-dd HH:mm") + " -- " + "VALID" if signature.is_valid else "INVALID")
            allSignaturesAreValid = allSignaturesAreValid and signature.is_valid

        if allSignaturesAreValid:
            print("Presentation is original, all signatures are valid.")
        else:
            print("Presentation has been modified.")