pdf-poppler/lib/convert.js

Convert PDF files into images using Poppler with promises. It achieves 10x faster performance compared to other PDF converters. Poppler library attached inside statically, so it has not require installation of poppler.

const path = require('path');
const {execFile} = require('child_process');

const FORMATS = ['png', 'jpeg', 'tiff', 'pdf', 'ps', 'eps', 'svg'];
const EXEC_OPTS = require('../index').exec_options;

let popplerPath = require('../index').path;

let defaultOptions = {
    format: 'jpeg',
    scale: 1024,
    out_dir: null,
    out_prefix: null,
    page: null
};

// module.exports = function (file, out_file, page_start, page_end) {
module.exports = function (file, opts) {
    return new Promise((resolve, reject) => {
        opts.format = FORMATS.includes(opts.format) ? opts.format : defaultOptions.format;
        opts.scale = opts.scale || defaultOptions.scale;
        opts.out_dir = opts.out_dir || defaultOptions.out_dir;
        opts.out_prefix = opts.out_prefix || path.dirname(file);
        opts.out_prefix = opts.out_prefix || path.basename(file, path.extname(file));
        opts.page = opts.page || defaultOptions.page;

        let args = [];
        args.push([`-${opts.format}`]);
        if (opts.page) {
            args.push(['-f']);
            args.push([parseInt(opts.page)]);
            args.push(['-l']);
            args.push([parseInt(opts.page)]);
        }
        if (opts.scale) {
            args.push(['-scale-to']);
            args.push([parseInt(opts.scale)]);
        }
        args.push(`${file}`);
        args.push(`${path.join(opts.out_dir, opts.out_prefix)}`);

        execFile(path.join(popplerPath, 'pdftocairo'), args, EXEC_OPTS, (err, stdout, stderr) => {
            if (err) {
                reject(err);
            }
            else {
                resolve(stdout);
            }
        });
    });
};