autorotate.js

// https://github.com/EyalAr/lwip/issues/100#issuecomment-71363633

var fs = require('fs');
var exif = require('exif-parser');
var lwip = require('lwip');

// path is the path to your image
fs.readFile(path, function (err, data) {
  if (err) throw err;
  var exifData = false;
  // ext is the extension of the image
  if(ext == "jpg"){
    exifData = exif.create(data).parse();
  }
  lwip.open(data, ext, function(err, image){
    if(err) throw err;
    if(exifData){
      switch( exifData.tags.Orientation ) {
        case 2:
        image = image.batch().flip('x'); // top-right - flip horizontal
        break;
        case 3:
        image = image.batch().rotate(180); // bottom-right - rotate 180
        break;
        case 4:
        image = image.batch().flip('y'); // bottom-left - flip vertically
        break;
        case 5:
        image = image.batch().rotate(90).flip('x'); // left-top - rotate 90 and flip horizontal
        break;
        case 6:
        image = image.batch().rotate(90); // right-top - rotate 90
        break;
        case 7:
        image = image.batch().rotate(270).flip('x'); // right-bottom - rotate 270 and flip horizontal
        break;
        case 8:
        image = image.batch().rotate(270); // left-bottom - rotate 270
        break;
      }
    }else{
      image = image.batch();
    }
    // image can now be used as per normal with batch
    // eg. image.resize(200, 200)....
  });
});