How to merge multiple PNG files together in Node.JS

Merging PNG files with Node.JS is actually a lot more annoying than it might seem. For that reason, we will be avoiding the conventional method in favor of something a little easier: an API.

We will use npm install to add our client via this command:

npm install cloudmersive-convert-api-client --save

Next on the agenda, calling out PNG merging function with this code snippet:

var CloudmersiveConvertApiClient = require('cloudmersive-convert-api-client');
var defaultClient = CloudmersiveConvertApiClient.ApiClient.instance;
// Configure API key authorization: Apikey
var Apikey = defaultClient.authentications['Apikey'];
Apikey.apiKey = 'YOUR API KEY';
// Uncomment the following line to set a prefix for the API key, e.g. "Token" (defaults to null)
//Apikey.apiKeyPrefix = 'Token';
var apiInstance = new CloudmersiveConvertApiClient.MergeDocumentApi();
var inputFile1 = "/path/to/file"; // File | First input file to perform the operation on.
var inputFile2 = "/path/to/file"; // File | Second input file to perform the operation on (more than 2 can be supplied).
var callback = function(error, data, response) {
if (error) {
console.error(error);
} else {
console.log('API called successfully. Returned data: ' + data);
}
};
apiInstance.mergeDocumentPng(inputFile1, inputFile2, callback);

To finish, simply input your PNG files in their desired vertical order. It’s really as easy as that! We have a variety of related API functions that you might find useful, including image and document format conversion, as well as image editing and facial recognition.