node-pdfjam

Npm package for using pdfjam utilities.

This project for now mainly implements the 'nup' capabilities. It can merge multiple pdfs into one, and also merge pages of pdfs so 4 pages would appear in one for example. More info here

Here is a demonstration

/* We are using await / async syntax here from node 8+, you can also use Promise syntax instead */
const pdfjam = require('pdfjam');

async function main() {
    /* Standard conversion of pdf with pages in a 2x2 layout */
    await pdfjam.nup('file.pdf', 2, 2,  {
        /* Suffix the new pdf file will have, `${originalName}-{suffix}.pdf`, by default is 'nup' */
        suffix: '2x2'
    });

    /* Just merge files, no page layout. Suffix is "pdfjam" in this case */
    await pdfjam(['file1.pdf', 'file2.pdf', 'file3.pdf'],  {
        // nup : "2x2" <- nup can be used through options
        // default suffix is "pdfjam" here
        // In fact the options argument is never mandatory
    });

    /* Conversion of pdf with pages in a 1x2 layout */
    await pdfjam.nup('file.pdf', 1, 2,  {
        /* Destination file, overrides suffix */
        outfile: 'file-converted.pdf'
    });

    /* Output in landscape mode, with paper size specified (by default A4) */
    await pdfjam.nup('file.pdf', 2, 1,  {
        orientation: 'landscape',
        papersize: '{1920px,1080px}' /* Can also use cm as unit */
        scale: 0.9 /* Reduce input page sizes a bit */
    });

    /* Merge multiple files in one, with the output a layout of 2x2 */
    await pdfjam.nup(['file1.pdf', 'file2.pdf', 'file3.pdf'], 2, 2,  {
        scale: 0.9 /* Reduce input page sizes a bit */
    });

    /* Merge multiple slides and adjust margins */
    await pdfjam(['slide1.pdf', 'slide2.pdf', 'slide3.pdf', 'slide4.pdf', 'slide5.pdf'], {
        outfile: "slides.pdf",
        trim: "-6cm -1cm 13cm 8cm",
        scale: 0.4
    });
}

main().then(() => {
    console.log("All done!");
})

Requirements

Pdfjam is needed. On debian systems, you can get it like that:

sudo apt install texlive-extra-utils

Note that this installs 600MB of software if you don't already have a LaTeX infrastructure.

Node version 8+ is expected. If you want to update your node version, you can do:

sudo npm install -g n
sudo n stable

Installation

Run this in your project directory:

npm i pdfjam  #add --save if your npm is < 5.0

Documentation

All functions return promises. The output directory of pdfjam is the working directory of your program (process.cwd()), but you can specify an absolute path in the outfile option.

pdfjam(input: string | string[], options: object)

Invokes pdfjam with the input given. If an array of strings is given as input, then the input files will be merged in the output, unless the batch options is provided, in which case there will be as many output files as input files.

Here are the valid values for options:

• suffix {string = 'pdfjam'}: What to append to the input filename to get the output filename. Overriden by the outfile option. Default value is "pdfjam". The output file name will look like basename-suffix.pdf.
• outfile {string}: Output pdf file, overrides suffix if supplied.
• orientation {'portrait'|'landscape'} : Orientation of the output.
• batch {boolean = false}: If set to true, will process each input file individually and produce an output file for each.
• scale {number = 1.0}: Can resize the pages of the input in the output.
• papersize {string = "{21cm,29.7cm}"}: Size of the pages in the output. Unit can be cm or px or in.
• trim {string = "0cm 0cm 0cm 0cm"}: Remove margins from the input pages. Can also add margins by using negative numbers.
• nup {string = "1x1"}: Page layout in the output pdf.

pdfjam.nup (input: string | string[], rows: number, cols: number, options: object)

Helper for page layout. Calls pdfjam with the nup option, as well as the provided options, and if no suffix or outfile is provided, will set the suffix to "nup".

Contributing

There are many more options that can easily be added to the module, such as paper type (paper: 'a4paper') or page color.

I very welcome contributions or even taking over of the project. This project was made in order to fill one of my particular needs, the use of pdfnup, so I welcome any contribution adding more of pdjam's features.

I also welcome any contribution in the form of tests, travis integration, using a build script to make the project compatible with older node versions and so on.