tiff-multipage

let mp = require('tiff-multipage');

let output_path = './output/OUT.TIFF';

let input_paths = ['./input/INPUT1.TIFF',
                   './input/INPUT2.TIFF',
                   './input/INPUT3.TIFF'];

// Async version
mp.JoinAsync(output_path, input_paths, function (err) {
    if (err) console.log(err);
});

// Sync version
try {
    mp.joinSync(output_path, input_paths);
} catch (err) {
    console.error(err);
}