C++ 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. C++

#include <CkFileAccess.h>
#include <CkJsonObject.h>
#include <CkPdf.h>

void ChilkatSample(void)
    {
    bool 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

    CkFileAccess fac;
    CkJsonObject json;
    CkJsonObject jsonOut;

    CkPdf pdf1;
    success = pdf1.LoadFile("qa_data/pdf/watersense_accomplishments.pdf");
    if (success == false) {
        std::cout << pdf1.lastErrorText() << "\r\n";
        return;
    }

    json.UpdateInt("compressionLevel",1);
    success = pdf1.Optimize("optimize",json,jsonOut);
    if (success == false) {
        std::cout << pdf1.lastErrorText() << "\r\n";
        return;
    }

    success = pdf1.WriteFile("qa_output/watersense_level1.pdf");
    if (success == false) {
        std::cout << pdf1.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "level 1: " << fac.FileSize("qa_output/watersense_level1.pdf") << "\r\n";

    CkPdf pdf9;
    success = pdf9.LoadFile("qa_data/pdf/watersense_accomplishments.pdf");
    if (success == false) {
        std::cout << pdf9.lastErrorText() << "\r\n";
        return;
    }

    json.UpdateInt("compressionLevel",9);
    success = pdf9.Optimize("optimize",json,jsonOut);
    if (success == false) {
        std::cout << pdf9.lastErrorText() << "\r\n";
        return;
    }

    success = pdf9.WriteFile("qa_output/watersense_level9.pdf");
    if (success == false) {
        std::cout << pdf9.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "level 9: " << fac.FileSize("qa_output/watersense_level9.pdf") << "\r\n";

    //  A level outside 1..9 fails, and LastErrorText says why.
    CkPdf pdfBad;
    success = pdfBad.LoadFile("qa_data/pdf/watersense_accomplishments.pdf");
    if (success == false) {
        std::cout << pdfBad.lastErrorText() << "\r\n";
        return;
    }

    json.UpdateInt("compressionLevel",12);
    success = pdfBad.Optimize("optimize",json,jsonOut);
    if (success == false) {
        std::cout << "compressionLevel 12 was refused, as it should be." << "\r\n";
    }
    }