Ruby 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. Ruby

require 'chilkat'

success = 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 watersense_accomplishments.pdf

fac = Chilkat::CkFileAccess.new()
json = Chilkat::CkJsonObject.new()
jsonOut = Chilkat::CkJsonObject.new()

pdf1 = Chilkat::CkPdf.new()
success = pdf1.LoadFile("qa_data/pdf/watersense_accomplishments.pdf")
if (success == false)
    print pdf1.lastErrorText() + "\n";
    exit
end

json.UpdateInt("compressionLevel",1)
success = pdf1.Optimize("optimize",json,jsonOut)
if (success == false)
    print pdf1.lastErrorText() + "\n";
    exit
end

success = pdf1.WriteFile("qa_output/watersense_level1.pdf")
if (success == false)
    print pdf1.lastErrorText() + "\n";
    exit
end

print "level 1: " + fac.FileSize("qa_output/watersense_level1.pdf").to_s() + "\n";

pdf9 = Chilkat::CkPdf.new()
success = pdf9.LoadFile("qa_data/pdf/watersense_accomplishments.pdf")
if (success == false)
    print pdf9.lastErrorText() + "\n";
    exit
end

json.UpdateInt("compressionLevel",9)
success = pdf9.Optimize("optimize",json,jsonOut)
if (success == false)
    print pdf9.lastErrorText() + "\n";
    exit
end

success = pdf9.WriteFile("qa_output/watersense_level9.pdf")
if (success == false)
    print pdf9.lastErrorText() + "\n";
    exit
end

print "level 9: " + fac.FileSize("qa_output/watersense_level9.pdf").to_s() + "\n";

#  A level outside 1..9 fails, and LastErrorText says why.
pdfBad = Chilkat::CkPdf.new()
success = pdfBad.LoadFile("qa_data/pdf/watersense_accomplishments.pdf")
if (success == false)
    print pdfBad.lastErrorText() + "\n";
    exit
end

json.UpdateInt("compressionLevel",12)
success = pdfBad.Optimize("optimize",json,jsonOut)
if (success == false)
    print "compressionLevel 12 was refused, as it should be." + "\n";
end