VBScript Requires Chilkat v11.7.0+

Deflate Compression Level When Optimizing a PDF

See more PDF Optimization Examples

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. VBScript

Dim fso, outFile
Set fso = CreateObject("Scripting.FileSystemObject")
'Create a Unicode (utf-16) output text file.
Set outFile = fso.CreateTextFile("output.txt", True, True)

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

set fac = CreateObject("Chilkat.FileAccess")
set json = CreateObject("Chilkat.JsonObject")
set jsonOut = CreateObject("Chilkat.JsonObject")

set pdf1 = CreateObject("Chilkat.Pdf")
success = pdf1.LoadFile("qa_data/pdf/watersense_accomplishments.pdf")
If (success = 0) Then
    outFile.WriteLine(pdf1.LastErrorText)
    WScript.Quit
End If

success = json.UpdateInt("compressionLevel",1)
success = pdf1.Optimize("optimize",json,jsonOut)
If (success = 0) Then
    outFile.WriteLine(pdf1.LastErrorText)
    WScript.Quit
End If

success = pdf1.WriteFile("qa_output/watersense_level1.pdf")
If (success = 0) Then
    outFile.WriteLine(pdf1.LastErrorText)
    WScript.Quit
End If

outFile.WriteLine("level 1: " & fac.FileSize("qa_output/watersense_level1.pdf"))

set pdf9 = CreateObject("Chilkat.Pdf")
success = pdf9.LoadFile("qa_data/pdf/watersense_accomplishments.pdf")
If (success = 0) Then
    outFile.WriteLine(pdf9.LastErrorText)
    WScript.Quit
End If

success = json.UpdateInt("compressionLevel",9)
success = pdf9.Optimize("optimize",json,jsonOut)
If (success = 0) Then
    outFile.WriteLine(pdf9.LastErrorText)
    WScript.Quit
End If

success = pdf9.WriteFile("qa_output/watersense_level9.pdf")
If (success = 0) Then
    outFile.WriteLine(pdf9.LastErrorText)
    WScript.Quit
End If

outFile.WriteLine("level 9: " & fac.FileSize("qa_output/watersense_level9.pdf"))

'  A level outside 1..9 fails, and LastErrorText says why.
set pdfBad = CreateObject("Chilkat.Pdf")
success = pdfBad.LoadFile("qa_data/pdf/watersense_accomplishments.pdf")
If (success = 0) Then
    outFile.WriteLine(pdfBad.LastErrorText)
    WScript.Quit
End If

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


outFile.Close