B4X Requires Chilkat v11.7.0+

Optimizing an Encrypted PDF

See more PDF Optimization Examples

Demonstrates optimizing a PDF that is encrypted. Set the password before loading, exactly as for any other operation; the optimized PDF keeps the security it had, so the output still needs the same password. Because Chilkat honours the permissions recorded in the document, optimizing requires owner rights or the "modify" permission: a PDF opened with a user password that forbids modification can be audited but not optimized. B4X

Dim success As Boolean = False

'  This example requires the Chilkat API to have been previously unlocked.
'  See Global Unlock Sample for sample code.

'  The PDF used in this example is available at encrypted_user_password.pdf

Dim pdf As ChilkatPdf
pdf.Initialize("pdf")

'  The password must be set before loading.
pdf.UserPassword = "secret"
success = pdf.LoadFile("qa_data/pdf/encrypted_user_password.pdf")
If success = False Then
    Log(pdf.LastErrorText)
    Return
End If


'  What security does the file have, and may it be modified?
Dim json As ChilkatJsonObject
json.Initialize
Dim jsonOut As ChilkatJsonObject
jsonOut.Initialize
success = pdf.Protection("getInfo", json, jsonOut)
If success = False Then
    Log(pdf.LastErrorText)
    Return
End If

Log("encrypted: " & jsonOut.BoolOf("loaded.encrypted"))
Log("method:    " & jsonOut.StringOf("loaded.method"))
Log("openedWith: " & jsonOut.StringOf("loaded.openedWith"))
Log("may modify: " & jsonOut.BoolOf("loaded.permissions.modify"))

success = pdf.Optimize("optimize", json, jsonOut)
If success = False Then
    Log(pdf.LastErrorText)
    Return
End If

success = pdf.WriteFile("qa_output/encrypted_optimized.pdf")
If success = False Then
    Log(pdf.LastErrorText)
    Return
End If

Log("bytesSaved: " & jsonOut.IntOf("bytesSaved"))

'  The output is still encrypted with the same security: loading it without the password fails.
Dim noPassword As ChilkatPdf
noPassword.Initialize("noPassword")
success = noPassword.LoadFile("qa_output/encrypted_optimized.pdf")
Dim q As ChilkatJsonObject
q.Initialize
Dim qOut As ChilkatJsonObject
qOut.Initialize
success = noPassword.ExtractText("assess", q, qOut)
Log("passwordRequired without the password: " & qOut.BoolOf("quality.passwordRequired"))

'  With the password it reads normally.
Dim withPassword As ChilkatPdf
withPassword.Initialize("withPassword")
withPassword.UserPassword = "secret"
success = withPassword.LoadFile("qa_output/encrypted_optimized.pdf")
If success = False Then
    Log(withPassword.LastErrorText)
    Return
End If

Log("pages: " & withPassword.NumPages)