(Node.js) Update a String Property in XMP

Demonstrates how to open a JPG or TIF image file, access the XMP metadata, and update the value of a string property. (If the string property does not already exist, it is created.)

Install Chilkat for Node.js and Electron using npm at Chilkat npm packages for Node.js Chilkat npm packages for Electron on Windows, Linux, MacOSX, and ARM

var os = require('os');
if (os.platform() == 'win32') {  
    if (os.arch() == 'ia32') {
        var chilkat = require('@chilkat/ck-node21-win-ia32');
    } else {
        var chilkat = require('@chilkat/ck-node21-win64'); 
    }
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node21-arm');
    } else if (os.arch() == 'x86') {
        var chilkat = require('@chilkat/ck-node21-linux32');
    } else {
        var chilkat = require('@chilkat/ck-node21-linux64');
    }
} else if (os.platform() == 'darwin') {
    if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node21-mac-m1');
    } else {
        var chilkat = require('@chilkat/ck-node21-macosx');
    }
}

function chilkatExample() {

    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    var xmp = new chilkat.Xmp();

    // Load a JPG or TIF image file.
    var success = xmp.LoadAppFile("qa_data/xmp/AJ_123642_1511.tif");
    if (success !== true) {
        console.log(xmp.LastErrorText);
        return;
    }

    console.log("Num embedded XMP docs: " + xmp.NumEmbedded);

    // This example assumes that XMP metadata is already present in the image file.
    if (xmp.NumEmbedded == 0) {
        console.log("No XMP metadata already exists..");
        return;
    }

    // Get the XMP metadata.
    // xml: Xml
    var xml;
    xml = xmp.GetEmbedded(0);

    // Show the XML:
    console.log(xml.GetXml());

    // Update (overwrite) a string property.
    xmp.AddSimpleStr(xml,"NumberofTimes","123");

    success = xmp.SaveAppFile("qa_output/updated.tif");
    if (success !== true) {
        console.log(xmp.LastErrorText);
        return;
    }

    console.log("Success.");

}

chilkatExample();