Tcl Requires Chilkat v11.7.0+

Shrink a PDF Losslessly

See more PDF Optimization Examples

Demonstrates the "optimize" operation with the default options, which is the lossless preset: nothing is resampled, recoloured or thrown away, so every page looks exactly as it did and all the text is still there. The changes are kept in memory until WriteFile (or WriteBd) is called. Note that the real saving is "fileSize" minus the size of the file that was written, not "bytesSaved": the rewrite also packs objects into object streams and writes a compact cross-reference stream, which belongs to no option. Tcl

load ./chilkat.dll

set 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 grand_canyon_hiking_guide.pdf

set pdf [new_CkPdf]

set success [CkPdf_LoadFile $pdf "qa_data/pdf/grand_canyon_hiking_guide.pdf"]
if {$success == 0} then {
    puts [CkPdf_lastErrorText $pdf]
    delete_CkPdf $pdf
    exit
}

#  An empty JSON means the default options: every lossless optimization, object streams generated,
#  old revisions dropped, deflate level 9.
set json [new_CkJsonObject]

set jsonOut [new_CkJsonObject]

set success [CkPdf_Optimize $pdf "optimize" $json $jsonOut]
if {$success == 0} then {
    puts [CkPdf_lastErrorText $pdf]
    delete_CkPdf $pdf
    delete_CkJsonObject $json
    delete_CkJsonObject $jsonOut
    exit
}

#  Nothing has been written yet.  WriteFile (or WriteBd) produces the optimized PDF.
set success [CkPdf_WriteFile $pdf "qa_output/grand_canyon_optimized.pdf"]
if {$success == 0} then {
    puts [CkPdf_lastErrorText $pdf]
    delete_CkPdf $pdf
    delete_CkJsonObject $json
    delete_CkJsonObject $jsonOut
    exit
}

set fac [new_CkFileAccess]

set sizeBefore [CkJsonObject_IntOf $jsonOut "fileSize"]
set sizeAfter [CkFileAccess_FileSize $fac "qa_output/grand_canyon_optimized.pdf"]

puts "before: $sizeBefore"
puts "after:  $sizeAfter"
puts "saved:  [expr $sizeBefore - $sizeAfter]"

#  What the options themselves account for.  This is smaller than the real saving above, because the
#  rewrite's own gains (object streams, the cross-reference stream, the old sections left behind)
#  belong to no single option.
puts "bytesSaved (options only): [CkJsonObject_IntOf $jsonOut bytesSaved]"

delete_CkPdf $pdf
delete_CkJsonObject $json
delete_CkJsonObject $jsonOut
delete_CkFileAccess $fac