diff --git a/src/filters.py b/src/filters.py
index e302af5..e1f8427 100644
--- a/src/filters.py
+++ b/src/filters.py
@@ -8,6 +8,7 @@ import cv2 as cv
 from skimage import filters as skiflt
 from skimage import restoration as skirest
 #from scipy import signal as sig
+from PIL import Image, ImageFilter
 
 
 # Parent class for all the filters
@@ -110,6 +111,53 @@ class bilateral(filter):
         self.img = cv.bilateralFilter(self.img, d, sigmaColor, sigmaSpace)
 
 
+class scale_values(filter):
+    ''' Scale values of the image to use the entire range of data type.
+    This should remove the line height issues.
+    '''
+    def __init__(self, img):
+        super().__init__(img)
+
+    def apply(self, params):
+        # do this once for inverted image and once for original
+        # this is done to get whiter whites and blacker blacks
+        # which helps to get exact line height on stl model
+        tmp = cv.bitwise_not(self.img.astype(np.uint8))
+        coef = 255 / np.max(tmp)
+        tmp = tmp * coef
+        self.img = cv.bitwise_not(tmp.astype(np.uint8))
+        coef = 255 / np.max(tmp)
+        tmp = tmp * coef
+
+
+class binarize(filter):
+    def init(self, img):
+        super().__init__(img)
+
+    def apply(self, params):
+        threshold = int(params["threshold"]) if params["threshold"] else 128
+        maxval = int(params["maxval"]) if params["maxval"] else 255
+        type = int(params["type"]) if params["type"] else 0
+
+        #print("with params: threshold: " + str(threshold) +
+        #      " maxval: " + str(maxval) + " type: " + str(type))
+        self.img = cv.threshold(self.img, threshold, maxval, type)[1]
+
+
+class add_margin(filter):
+    def init(self, img):
+        super().__init__(img)
+
+    def apply(self, params):
+        margin = int(params["margin"]) if params["margin"] else 10
+        color = int(params["color"]) if params["color"] else 255
+        self.fig.set_size_inches(
+            ((self.width + 2 * margin) / self.dpi, (self.height + 2 * margin) / self.dpi))
+        self.img = cv.copyMakeBorder(
+            self.img, margin, margin, margin, margin, cv.BORDER_CONSTANT, value=color)
+        self.height, self.width = self.img.shape
+        
+
 class denoise(filter):
     # TODO possibly not necessary
     def __init__(self, img):
@@ -263,6 +311,7 @@ class morph(filter):
         super().__init__(img)
 
     def apply(self, params):
+        # TODO: this is probably better with binarized image
         kernel = np.matrix(params["kernel"]) if params["kernel"] else np.ones(
             (3, 3), np.uint8)
         iterations = int(params["iterations"]) if params["iterations"] else 1
diff --git a/src/main.py b/src/main.py
index 2743c31..105aa96 100644
--- a/src/main.py
+++ b/src/main.py
@@ -7,7 +7,6 @@
 import argparse as ap
 import sys
 import json
-import math 
 from os.path import exists
 
 # Libraries for image processing
@@ -159,7 +158,8 @@ class app:
                            "ksize", "kernel", "sigmaX", "sigmaY",
                            "sigmaColor", "sigmaSpace", "d", "anchor", "iterations",
                            "op", "strength", "amount", "radius", "weight", "channelAxis",
-                           "theta", "sigma", "lambda", "gamma", "psi", "shape", "percent", "threshold"}
+                           "theta", "sigma", "lambda", "gamma", "psi", "shape", "percent", 
+                           "threshold", "maxval", "type", "margin", "color"}
 
         for key in possible_params:
             if params.get(key) is None:
@@ -208,17 +208,14 @@ class app:
 
         # gets empty figure and ax with dimensions of input image
         self.height, self.width = self.img.shape
-        fig, ax = self.get_empty_figure()
+        self.fig, ax = self.get_empty_figure()
 
-        # print("Height: " + str(self.height) + " px and width: "
-        #      + str(self.width) + " px", file=sys.stderr)
-        
         if self.mirror is True:
             self.mirror_image()
 
         # Apply all filters and save image
         self.apply_filters()
-        self.save_image(fig, ax)
+        self.save_image(self.fig, ax)
         plt.close()
 
     def get_empty_figure(self):
@@ -260,7 +257,7 @@ class app:
 
         # Colormap must be set to grayscale to avoid color mismatch.
         ax.imshow(self.img, cmap="gray")
-        fig.savefig(fname=self.output_file, dpi=self.dpi)
+        fig.savefig(fname=self.output_file)
 
 #------------------------- STL GENERATION -------------------------#
 
@@ -336,8 +333,7 @@ class app:
         '''
 
         # TODO: somehow compress this to fit it onto the model
-        self.id = self.input_file.split(
-            "/")[-1].split(".")[0] + "_" + self.preset_name
+        self.id = self.input_file.split("/")[-1].split(".")[0] + "_" + self.preset_name
         # TODO: hash is not unique, find a better way
         # TODO: stl file format has 80 chars for header, use that space to store info
         # python generates a random value for security reasons, it has to be turned off
@@ -615,6 +611,7 @@ class app:
     def save_stl(self):
         '''Save final mesh to stl file.
         '''
+
         # TODO: add a hash function to create ID specific to
         # input image + preset from config. file or from console + input params
         # TODO: add the full parameters and filters to a file inside output dir.