C++ Requires Chilkat v11.7.0+

Audit a PDF First, Optimize Only If It Is Worth It

See more PDF Optimization Examples

Demonstrates deciding whether to rewrite a PDF at all. "audit" costs a fraction of a second and changes nothing, so a batch job can audit every file and optimize only those where enough would be saved. Here the threshold is a tenth of the file; a file already as small as it can be is left alone. C++

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

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

    CkJsonObject json;
    CkJsonObject jsonOut;
    success = pdf.Optimize("audit",json,jsonOut);
    if (success == false) {
        std::cout << pdf.lastErrorText() << "\r\n";
        return;
    }

    int fileSize = jsonOut.IntOf("fileSize");
    int estimated = jsonOut.IntOf("estimatedSavings.total");
    std::cout << "fileSize:  " << fileSize << "\r\n";
    std::cout << "estimated: " << estimated << "\r\n";

    //  Only bother when at least a tenth of the file would go.
    if (estimated > (fileSize / 10)) {
        std::cout << "Worth optimizing." << "\r\n";
        success = pdf.Optimize("optimize",json,jsonOut);
        if (success == false) {
            std::cout << pdf.lastErrorText() << "\r\n";
            return;
        }

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

        std::cout << "bytesSaved: " << jsonOut.IntOf("bytesSaved") << "\r\n";
    }
    else {
        std::cout << "Already small enough; left as it is." << "\r\n";
    }
    }