Lua Requires Chilkat v11.7.0+

Why a PDF Optimization Was Skipped

See more PDF Optimization Examples

Demonstrates the "skipped" array, which lists the options that were asked for but not applied, each with a reason and, where it is page-specific, the pages. An option is skipped when it is reserved for a later release (mergeFontSubsets, compactType1Fonts), when the rules of the file forbid it (objectStreams in a PDF/A-1 file), or when the content could not be parsed safely (tidyContent and coalesceContent on a page whose content stream the parser does not understand). Nothing is ever changed on a guess: an option that cannot be applied safely is skipped and reported. Lua

local chilkat = require("chilkat")

-- 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

local pdf = chilkat.Pdf.new()
local success = pdf:load_file("qa_data/pdf/grand_canyon_hiking_guide.pdf")
if not success then
    print(pdf.last_error_text)
    return
end

-- Ask for the two options that are reserved for a later release.
local json = chilkat.JsonObject.new()
json:update_bool("mergeFontSubsets", true)
json:update_bool("compactType1Fonts", true)

local jsonOut = chilkat.JsonObject.new()
success = pdf:optimize("audit", json, jsonOut)
if not success then
    print(pdf.last_error_text)
    return
end

local i = 0
local numSkipped = jsonOut:size_of_array("skipped")
print("skipped: " .. numSkipped)
while i < numSkipped do
    jsonOut.i = i
    print("   " .. jsonOut:string_of("skipped[i].option") .. " - " .. jsonOut:string_of("skipped[i].reason"))
    i = i + 1
end

-- A skipped option is not a failure: Optimize returns true, the other options are applied, and the
-- report says exactly what was left undone.