ghostScriptStream.js

var spawn = require('child_process').spawn;
var Stream = require('stream');


var pdfStream = module.exports = function () {
	var convertPdfs = function(streamIn){

		var command = 'gs';
		var args = [
			"-dNOPAUSE",
			"-sDEVICE=png16m",
			"-r600",
			"-sOutputFile=-",
			"-q",
			"-_",
			"-c quit"
		];

		var proc = spawn(command, args);

		var stream = new Stream();

		proc.stderr.on('data', stream.emit.bind(stream, 'error'));
		proc.stdout.on('data', stream.emit.bind(stream, 'data'));
		proc.stdout.on('end', stream.emit.bind(stream, 'end'));
		proc.on('error', stream.emit.bind(stream, 'error'));

		streamIn.pipe(proc.stdin);

		return stream;
	};

	return convertPdfs;
};

route.js

app.post('/upload-stream', authFilter, function (req, res) {
    var file = req.files['file'];
    var fileStream = fs.createReadStream(file.path);
    res.writeHead(200, { "Content-Type": "application/json",
                         "Cache-control": "no-cache" });
    var buf = [];
    pdfStream(fileStream).on('data', function (chunk) {
        buf.push(chunk);
    }).on('end', function () {
        var splitBy = '�PNG\r\n\u001a\n\u0000\u0000\u0000\rIHDR';
        var buffer = Buffer.concat(buf);
        console.log(buffer);
        var splited = buffer.toString().split(splitBy);
        console.log(splited.length);
        var imgs  = [];
        _.forEach(splited, function (k) {
            console.log(">>>>>");
            if( k !== "") {
                imgs.push({'image': new Buffer(k)});
                //res.write('<img src=\'data:image/png;base64,' + k.toString('base64') + '\/>');
            }
        });
        res.write(_(JSON.stringify({data: imgs})).toString());
        res.end();
    });
});