Node.js 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. Node.js

NODEJS_PRELUDE

function chilkatExample() {

    var 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

    var fac = new chilkat.FileAccess();
    var json = new chilkat.JsonObject();
    var jsonOut = new chilkat.JsonObject();

    var pdf1 = new chilkat.Pdf();
    success = pdf1.LoadFile("qa_data/pdf/watersense_accomplishments.pdf");
    if (success == false) {
        console.log(pdf1.LastErrorText);
        return;
    }

    json.UpdateInt("compressionLevel",1);
    success = pdf1.Optimize("optimize",json,jsonOut);
    if (success == false) {
        console.log(pdf1.LastErrorText);
        return;
    }

    success = pdf1.WriteFile("qa_output/watersense_level1.pdf");
    if (success == false) {
        console.log(pdf1.LastErrorText);
        return;
    }

    console.log("level 1: " + fac.FileSize("qa_output/watersense_level1.pdf"));

    var pdf9 = new chilkat.Pdf();
    success = pdf9.LoadFile("qa_data/pdf/watersense_accomplishments.pdf");
    if (success == false) {
        console.log(pdf9.LastErrorText);
        return;
    }

    json.UpdateInt("compressionLevel",9);
    success = pdf9.Optimize("optimize",json,jsonOut);
    if (success == false) {
        console.log(pdf9.LastErrorText);
        return;
    }

    success = pdf9.WriteFile("qa_output/watersense_level9.pdf");
    if (success == false) {
        console.log(pdf9.LastErrorText);
        return;
    }

    console.log("level 9: " + fac.FileSize("qa_output/watersense_level9.pdf"));

    //  A level outside 1..9 fails, and LastErrorText says why.
    var pdfBad = new chilkat.Pdf();
    success = pdfBad.LoadFile("qa_data/pdf/watersense_accomplishments.pdf");
    if (success == false) {
        console.log(pdfBad.LastErrorText);
        return;
    }

    json.UpdateInt("compressionLevel",12);
    success = pdfBad.Optimize("optimize",json,jsonOut);
    if (success == false) {
        console.log("compressionLevel 12 was refused, as it should be.");
    }


}

chilkatExample();