Visual Basic 6.0 Requires Chilkat v11.7.0+

Deflate Compression Level When Optimizing a PDF

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Demonstrates compressionLevel, which is the deflate level (1 to 9, 9 by default) used for every stream the optimizer re-encodes. Level 9 is the smallest and the slowest; level 1 is the quickest. The difference is usually a percent or two, so level 9 is the right default for a file that will be downloaded many times, and a lower level is worth considering only when a server optimizes PDFs on the fly. A value outside 1 to 9 is an error. Visual Basic 6.0

Dim success As Long
success = 0

'  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 watersense_accomplishments.pdf

Dim fac As New CkFileAccess
Dim json As New ChilkatJsonObject
Dim jsonOut As New ChilkatJsonObject

Dim pdf1 As New ChilkatPdf
success = pdf1.LoadFile("qa_data/pdf/watersense_accomplishments.pdf")
If (success = 0) Then
    Debug.Print pdf1.LastErrorText
    Exit Sub
End If

success = json.UpdateInt("compressionLevel",1)
success = pdf1.Optimize("optimize",json,jsonOut)
If (success = 0) Then
    Debug.Print pdf1.LastErrorText
    Exit Sub
End If

success = pdf1.WriteFile("qa_output/watersense_level1.pdf")
If (success = 0) Then
    Debug.Print pdf1.LastErrorText
    Exit Sub
End If

Debug.Print "level 1: " & fac.FileSize("qa_output/watersense_level1.pdf")

Dim pdf9 As New ChilkatPdf
success = pdf9.LoadFile("qa_data/pdf/watersense_accomplishments.pdf")
If (success = 0) Then
    Debug.Print pdf9.LastErrorText
    Exit Sub
End If

success = json.UpdateInt("compressionLevel",9)
success = pdf9.Optimize("optimize",json,jsonOut)
If (success = 0) Then
    Debug.Print pdf9.LastErrorText
    Exit Sub
End If

success = pdf9.WriteFile("qa_output/watersense_level9.pdf")
If (success = 0) Then
    Debug.Print pdf9.LastErrorText
    Exit Sub
End If

Debug.Print "level 9: " & fac.FileSize("qa_output/watersense_level9.pdf")

'  A level outside 1..9 fails, and LastErrorText says why.
Dim pdfBad As New ChilkatPdf
success = pdfBad.LoadFile("qa_data/pdf/watersense_accomplishments.pdf")
If (success = 0) Then
    Debug.Print pdfBad.LastErrorText
    Exit Sub
End If

success = json.UpdateInt("compressionLevel",12)
success = pdfBad.Optimize("optimize",json,jsonOut)
If (success = 0) Then
    Debug.Print "compressionLevel 12 was refused, as it should be."
End If