diff --git a/Makefile b/Makefile
index 55e065b8..231b4025 100644
--- a/Makefile
+++ b/Makefile
@@ -15,4 +15,12 @@ prospector: build-test
 
 .PHONY: pytest
 pytest: build-test
-	docker run --rm --env=PYTHONPATH=/opt/ --volume=$$(pwd)/results:/results --volume=$$(pwd)/tests:/tests tests bash -c 'cd /tests && pytest --durations=0 --verbose --color=yes'
+	docker run --rm --env=PYTHONPATH=/opt/ --volume=$$(pwd)/results:/results --volume=$$(pwd)/tests:/tests --volume=$$(pwd)/scan_to_paperless:/opt/scan_to_paperless tests bash -c 'cd /tests && pytest --durations=0 --verbose --color=yes'
+
+.PHONY: pytest-last-failed
+pytest-last-failed:
+	docker run --rm --env=PYTHONPATH=/opt/ --volume=$$(pwd)/results:/results --volume=$$(pwd)/tests:/tests --volume=$$(pwd)/scan_to_paperless:/opt/scan_to_paperless tests bash -c 'cd /tests && pytest --durations=0 --verbose --color=yes --last-failed'
+
+.PHONY: pytest-exitfirst
+pytest-exitfirst:
+	docker run --rm --env=PYTHONPATH=/opt/ --volume=$$(pwd)/results:/results --volume=$$(pwd)/tests:/tests --volume=$$(pwd)/scan_to_paperless:/opt/scan_to_paperless tests bash -c 'cd /tests && pytest --durations=0 --verbose --color=yes --exitfirst'
diff --git a/config.md b/config.md
index a8f207c2..a2017c63 100644
--- a/config.md
+++ b/config.md
@@ -30,5 +30,6 @@
   - **`min_box_black_crop`** *(number)*: The minimum black in a box on content find on witch one we will crop [%]. Default: `2`.
   - **`min_box_black_limit`** *(number)*: The minimum black in a box on content find the limits based on content [%]. Default: `2`.
   - **`min_box_black_empty`** *(number)*: The minimum black in a box on content find to determine if the page is empty [%]. Default: `2`.
+  - **`box_kernel_size`** *(number)*: The block size used in a box on content find [mm]. Default: `1.5`.
   - **`box_block_size`** *(number)*: The block size used in a box on content find [mm]. Default: `1.5`.
-  - **`box_threshold_value_c`** *(number)*: A variable of double type representing the constant used in the both methods (subtracted from the mean or weighted mean, used in a box on content find. Default: `25`.
+  - **`box_threshold_value_c`** *(number)*: A variable used on threshold, should be low on low contrast image, used in a box on content find. Default: `70`.
diff --git a/process.md b/process.md
index acf3459e..1b95efda 100644
--- a/process.md
+++ b/process.md
@@ -57,5 +57,6 @@
   - **`min_box_black_crop`** *(number)*: The minimum black in a box on content find on witch one we will crop [%]. Default: `2`.
   - **`min_box_black_limit`** *(number)*: The minimum black in a box on content find the limits based on content [%]. Default: `2`.
   - **`min_box_black_empty`** *(number)*: The minimum black in a box on content find to determine if the page is empty [%]. Default: `2`.
-  - **`box_block_size`** *(number)*: The block size used in a box on content find [mm]. Default: `1.5`.
-  - **`box_threshold_value_c`** *(number)*: A variable of double type representing the constant used in the both methods (subtracted from the mean or weighted mean, used in a box on content find. Default: `25`.
+  - **`box_kernel_size`** *(number)*: The block size used in a box on content find [mm]. Default: `1.5`.
+  - **`box_block_size`** *(number)*: The block size used in a box on threshold for content find [mm]. Default: `1.5`.
+  - **`box_threshold_value_c`** *(number)*: A variable used on threshold, should be low on low contrast image, used in a box on content find. Default: `70`.
diff --git a/scan_to_paperless/config.py b/scan_to_paperless/config.py
index c3a6aa88..772de929 100644
--- a/scan_to_paperless/config.py
+++ b/scan_to_paperless/config.py
@@ -81,10 +81,14 @@
         # The block size used in a box on content find [mm]
         #
         # default: 1.5
+        "box_kernel_size": Union[int, float],
+        # The block size used in a box on content find [mm]
+        #
+        # default: 1.5
         "box_block_size": Union[int, float],
-        # A variable of double type representing the constant used in the both methods (subtracted from the mean or weighted mean, used in a box on content find
+        # A variable used on threshold, should be low on low contrast image, used in a box on content find
         #
-        # default: 25
+        # default: 70
         "box_threshold_value_c": Union[int, float],
     },
     total=False,
diff --git a/scan_to_paperless/config_schema.json b/scan_to_paperless/config_schema.json
index 792c48db..c374048d 100644
--- a/scan_to_paperless/config_schema.json
+++ b/scan_to_paperless/config_schema.json
@@ -104,6 +104,11 @@
           "default": 2,
           "description": "The minimum black in a box on content find to determine if the page is empty [%]"
         },
+        "box_kernel_size": {
+          "type": "number",
+          "default": 1.5,
+          "description": "The block size used in a box on content find [mm]"
+        },
         "box_block_size": {
           "type": "number",
           "default": 1.5,
@@ -111,8 +116,8 @@
         },
         "box_threshold_value_c": {
           "type": "number",
-          "default": 25,
-          "description": "A variable of double type representing the constant used in the both methods (subtracted from the mean or weighted mean, used in a box on content find"
+          "default": 70,
+          "description": "A variable used on threshold, should be low on low contrast image, used in a box on content find"
         }
       }
     }
diff --git a/scan_to_paperless/process.py b/scan_to_paperless/process.py
index 5fea1872..d418bfae 100755
--- a/scan_to_paperless/process.py
+++ b/scan_to_paperless/process.py
@@ -326,12 +326,15 @@ def crop(context: Context, margin_horizontal: int, margin_vertical: int) -> None
     Margin in px
     """
     image = context.get_masked()
+    process_count = context.get_process_count()
     contours = find_contours(
         image,
+        f"{process_count}-crop",
         context.get_px_value("min_box_size_crop", 3),
         context.config["args"].get("min_box_black_crop", 2),
+        context.get_px_value("box_kernel_size", 1.5),
         context.get_px_value("box_block_size", 1.5),
-        context.config["args"].get("box_threshold_value_c", 25),
+        context.config["args"].get("box_threshold_value_c", 70),
     )
 
     if contours:
@@ -341,7 +344,7 @@ def crop(context: Context, margin_horizontal: int, margin_vertical: int) -> None
             save_image(
                 image,
                 context.root_folder,
-                "{}-crop".format(context.get_process_count()),
+                "{}-crop".format(process_count),
                 context.image_name,
                 True,
             )
@@ -547,13 +550,17 @@ def zero_ranges(values: np_ndarray_int) -> np_ndarray_int:
 
 def find_limit_contour(
     image: np_ndarray_int,
+    name: str,
     vertical: bool,
     min_box_size: float,
     min_box_black: Union[int, float],
-    block_size: Union[float, int] = 17,
-    threshold_value_c: Union[float, int] = 25,
+    kernel_size: Union[float, int] = 16,
+    block_size: Union[float, int] = 16,
+    threshold_value_c: Union[float, int] = 100,
 ) -> Tuple[List[int], List[Tuple[int, int, int, int]]]:
-    contours = find_contours(image, min_box_size, min_box_black, block_size, threshold_value_c)
+    contours = find_contours(
+        image, name, min_box_size, min_box_black, kernel_size, block_size, threshold_value_c
+    )
     image_size = image.shape[1 if vertical else 0]
 
     values = np.zeros(image_size)
@@ -578,11 +585,13 @@ def fill_limits(
     peaks, properties = find_lines(image, vertical)
     contours_limits, contours = find_limit_contour(
         image,
+        f"{context.get_process_count()}-limits",
         vertical,
         context.get_px_value("min_box_size_limit", 10),
         context.config["args"].get("min_box_black_limit", 2),
+        context.get_px_value("box_kernel_size", 1.5),
         context.get_px_value("box_block_size", 1.5),
-        context.config["args"].get("box_threshold_value_c", 25),
+        context.config["args"].get("box_threshold_value_c", 70),
     )
     for contour_limit in contours:
         draw_rectangle(image, contour_limit)
@@ -613,21 +622,26 @@ def fill_limits(
 
 def find_contours(
     image: np_ndarray_int,
+    name: str,
     min_size: Union[float, int],
     min_black: Union[float, int],
+    kernel_size: Union[float, int] = 16,
     block_size: Union[float, int] = 16,
-    threshold_value_c: Union[float, int] = 25,
+    threshold_value_c: Union[float, int] = 100,
 ) -> List[Tuple[int, int, int, int]]:
     gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
     block_size = int(round(block_size / 2) * 2)
+    kernel_size = int(round(kernel_size / 2))
 
     # Clean the image using otsu method with the inversed binarized image
     thresh = cv2.adaptiveThreshold(
         gray, 255, cv2.ADAPTIVE_THRESH_MEAN_C, cv2.THRESH_BINARY_INV, block_size + 1, threshold_value_c
     )
+    if os.environ.get("PROGRESS", "FALSE") == "TRUE":
+        cv2.imwrite(os.path.join(name, "threshold.png"), thresh)
 
     # Assign a rectangle kernel size
-    kernel = np.ones((5, 5), "uint8")
+    kernel = np.ones((kernel_size, kernel_size), "uint8")
     par_img = cv2.dilate(thresh, kernel, iterations=5)
 
     contours, _ = cv2.findContours(par_img.copy(), cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
@@ -640,7 +654,12 @@ def find_contours(
             contour_image = rgb2gray(contour_image)
             if ((1 - np.mean(contour_image)) * 100) > min_black:
                 result.append(
-                    (x + block_size / 2, y + block_size / 2, width - block_size, height - block_size)
+                    (
+                        x + kernel_size * 2,
+                        y + kernel_size * 2,
+                        width - kernel_size * 4,
+                        height - kernel_size * 4,
+                    )
                 )
 
     return result
@@ -665,7 +684,7 @@ def transform(
     images = []
     process_count = 0
 
-    if config["args"]["assisted_split"]:
+    if config["args"].get("assisted_split", False):
         config["assisted_split"] = []
 
     for index, img in enumerate(step["sources"]):
@@ -691,10 +710,12 @@ def transform(
         # Is empty ?
         contours = find_contours(
             context.get_masked(),
+            f"{context.get_process_count()}-is-empty",
             context.get_px_value("min_box_size_empty", 20),
             context.config["args"].get("min_box_black_crop", 2),
+            context.get_px_value("box_kernel_size", 1.5),
             context.get_px_value("box_block_size", 1.5),
-            context.config["args"].get("box_threshold_value_c", 25),
+            context.config["args"].get("box_threshold_value_c", 70),
         )
         if not contours:
             print("Ignore image with no content: {}".format(img))
@@ -702,7 +723,7 @@ def transform(
 
         tesseract(context)
 
-        if config["args"]["assisted_split"]:
+        if config["args"].get("assisted_split", False):
             assisted_split: scan_to_paperless.process_schema.AssistedSplit = {}
             name = os.path.join(root_folder, context.image_name)
             assert context.image is not None
@@ -739,7 +760,7 @@ def transform(
 
     return {
         "sources": images,
-        "name": "split" if config["args"]["assisted_split"] else "finalise",
+        "name": "split" if config["args"].get("assisted_split", False) else "finalise",
         "process_count": process_count,
     }
 
@@ -925,7 +946,7 @@ def finalise(
 
     images = step["sources"]
 
-    if config["args"]["append_credit_card"]:
+    if config["args"].get("append_credit_card", False):
         images2 = []
         for img in images:
             if os.path.exists(img):
diff --git a/scan_to_paperless/process_schema.json b/scan_to_paperless/process_schema.json
index 0be13fd1..3ffcfaca 100644
--- a/scan_to_paperless/process_schema.json
+++ b/scan_to_paperless/process_schema.json
@@ -108,15 +108,20 @@
           "default": 2,
           "description": "The minimum black in a box on content find to determine if the page is empty [%]"
         },
-        "box_block_size": {
+        "box_kernel_size": {
           "type": "number",
           "default": 1.5,
           "description": "The block size used in a box on content find [mm]"
         },
+        "box_block_size": {
+          "type": "number",
+          "default": 1.5,
+          "description": "The block size used in a box on threshold for content find [mm]"
+        },
         "box_threshold_value_c": {
           "type": "number",
-          "default": 25,
-          "description": "A variable of double type representing the constant used in the both methods (subtracted from the mean or weighted mean, used in a box on content find"
+          "default": 70,
+          "description": "A variable used on threshold, should be low on low contrast image, used in a box on content find"
         }
       }
     }
diff --git a/scan_to_paperless/process_schema.py b/scan_to_paperless/process_schema.py
index 66299a73..cbebed36 100644
--- a/scan_to_paperless/process_schema.py
+++ b/scan_to_paperless/process_schema.py
@@ -85,10 +85,14 @@
         # The block size used in a box on content find [mm]
         #
         # default: 1.5
+        "box_kernel_size": Union[int, float],
+        # The block size used in a box on threshold for content find [mm]
+        #
+        # default: 1.5
         "box_block_size": Union[int, float],
-        # A variable of double type representing the constant used in the both methods (subtracted from the mean or weighted mean, used in a box on content find
+        # A variable used on threshold, should be low on low contrast image, used in a box on content find
         #
-        # default: 25
+        # default: 70
         "box_threshold_value_c": Union[int, float],
     },
     total=False,
diff --git a/tests/600.expected.png b/tests/600.expected.png
new file mode 100644
index 00000000..1356834c
Binary files /dev/null and b/tests/600.expected.png differ
diff --git a/tests/600.png b/tests/600.png
new file mode 100644
index 00000000..98f6eec3
Binary files /dev/null and b/tests/600.png differ
diff --git a/tests/assisted-split-contour-1.expected.png b/tests/assisted-split-contour-1.expected.png
index 44ded90e..53d01855 100644
Binary files a/tests/assisted-split-contour-1.expected.png and b/tests/assisted-split-contour-1.expected.png differ
diff --git a/tests/assisted-split-contour-3.expected.png b/tests/assisted-split-contour-3.expected.png
index 6cba37cf..65d4a078 100644
Binary files a/tests/assisted-split-contour-3.expected.png and b/tests/assisted-split-contour-3.expected.png differ
diff --git a/tests/assisted-split-contour-5.expected.png b/tests/assisted-split-contour-5.expected.png
index 34d141ee..f324730d 100644
Binary files a/tests/assisted-split-contour-5.expected.png and b/tests/assisted-split-contour-5.expected.png differ
diff --git a/tests/assisted-split-join-1.expected.png b/tests/assisted-split-join-1.expected.png
index f2ae38c5..7afd7303 100644
Binary files a/tests/assisted-split-join-1.expected.png and b/tests/assisted-split-join-1.expected.png differ
diff --git a/tests/assisted-split-join-2.expected.png b/tests/assisted-split-join-2.expected.png
index 45ff08c1..f360e0f7 100644
Binary files a/tests/assisted-split-join-2.expected.png and b/tests/assisted-split-join-2.expected.png differ
diff --git a/tests/assisted-split-lines-1.expected.png b/tests/assisted-split-lines-1.expected.png
index beee2e0b..39c6ae2d 100644
Binary files a/tests/assisted-split-lines-1.expected.png and b/tests/assisted-split-lines-1.expected.png differ
diff --git a/tests/assisted-split-lines-3.expected.png b/tests/assisted-split-lines-3.expected.png
index 09b63cb3..c4333ded 100644
Binary files a/tests/assisted-split-lines-3.expected.png and b/tests/assisted-split-lines-3.expected.png differ
diff --git a/tests/assisted-split-lines-4.expected.png b/tests/assisted-split-lines-4.expected.png
index ebd35b68..c3676c60 100644
Binary files a/tests/assisted-split-lines-4.expected.png and b/tests/assisted-split-lines-4.expected.png differ
diff --git a/tests/assisted-split-lines-5.expected.png b/tests/assisted-split-lines-5.expected.png
index 1aaeb992..fba27c75 100644
Binary files a/tests/assisted-split-lines-5.expected.png and b/tests/assisted-split-lines-5.expected.png differ
diff --git a/tests/credit-card-1.expected.png b/tests/credit-card-1.expected.png
index 967894d5..d236de0f 100644
Binary files a/tests/credit-card-1.expected.png and b/tests/credit-card-1.expected.png differ
diff --git a/tests/test_process.py b/tests/test_process.py
index e21c1e6a..67f3fa70 100644
--- a/tests/test_process.py
+++ b/tests/test_process.py
@@ -19,8 +19,8 @@ def test_find_lines():
 
 
 def test_find_limit_contour():
-    limits, _ = process.find_limit_contour(load_image("limit-contour-1.png"), True, 40, 2)
-    assert limits == [1588]
+    limits, _ = process.find_limit_contour(load_image("limit-contour-1.png"), "test", True, 40, 2)
+    assert limits == [1592]
 
 
 def check_image_file(root_folder, image, name, level=0.9):
@@ -58,6 +58,7 @@ def test_crop():
     check_image(root_folder, process.crop_image(image, -100, 100, 200, 100, (255, 255, 255)), "crop-4")
     check_image(root_folder, process.crop_image(image, 100, 200, 100, 200, (255, 255, 255)), "crop-5")
     check_image(root_folder, process.crop_image(image, 200, 100, 200, 100, (255, 255, 255)), "crop-6")
+    shutil.rmtree(root_folder)
 
 
 def test_rotate():
@@ -72,6 +73,7 @@ def test_rotate():
     check_image(root_folder, process.rotate_image(image, -90, (255, 255, 255)), "rotate-4")
     check_image(root_folder, process.rotate_image(image, 270, (255, 255, 255)), "rotate-4")
     check_image(root_folder, process.rotate_image(image, 180, (255, 255, 255)), "rotate-5")
+    shutil.rmtree(root_folder)
 
 
 def init_test():
@@ -86,10 +88,10 @@ def init_test():
 @pytest.mark.parametrize(
     "type_,limit",
     [
-        ("lines", {"name": "VL0", "type": "line detection", "value": 1812, "vertical": True, "margin": 0}),
+        ("lines", {"name": "VL1", "type": "line detection", "value": 1812, "vertical": True, "margin": 0}),
         (
             "contour",
-            {"name": "VC0", "type": "contour detection", "value": 1617, "vertical": True, "margin": 0},
+            {"name": "VC0", "type": "contour detection", "value": 1616, "vertical": True, "margin": 0},
         ),
     ],
 )
@@ -108,7 +110,6 @@ def test_assisted_split_full(type_, limit):
         "args": {
             "assisted_split": True,
             "level": True,
-            "append_credit_card": False,
             "tesseract": False,
             "sharpen": True,
         },
@@ -153,6 +154,7 @@ def test_assisted_split_full(type_, limit):
         ]
     )
     check_image_file(root_folder, os.path.join(root_folder, "final.png"), f"assisted-split-{type_}-5")
+    shutil.rmtree(root_folder)
 
 
 # @pytest.mark.skip(reason='for test')
@@ -173,7 +175,6 @@ def test_assisted_split_join_full():
         "args": {
             "assisted_split": True,
             "level": True,
-            "append_credit_card": False,
             "tesseract": False,
         },
         "destination": os.path.join(root_folder, "final.pdf"),
@@ -217,6 +218,7 @@ def test_assisted_split_join_full():
         ]
     )
     check_image_file(root_folder, os.path.join(root_folder, "final.png"), "assisted-split-join-2")
+    shutil.rmtree(root_folder)
 
 
 # @pytest.mark.skip(reason='for test')
@@ -236,7 +238,6 @@ def test_assisted_split_booth():
         "args": {
             "assisted_split": True,
             "level": False,
-            "append_credit_card": False,
             "nocrop": True,
             "tesseract": False,
             "margin_horizontal": 0,
@@ -266,6 +267,7 @@ def test_assisted_split_booth():
     check_image_file(root_folder, step["sources"][1], "assisted-split-booth-2")
     check_image_file(root_folder, step["sources"][2], "assisted-split-booth-3")
     check_image_file(root_folder, step["sources"][3], "assisted-split-booth-4")
+    shutil.rmtree(root_folder)
 
 
 # @pytest.mark.skip(reason='for test')
@@ -280,9 +282,7 @@ def test_full(progress, experimental):
         os.makedirs(root_folder)
     config = {
         "args": {
-            "assisted_split": False,
             "level": True,
-            "append_credit_card": False,
             "tesseract": False,
         },
         "destination": os.path.join(root_folder, "final.pdf"),
@@ -318,6 +318,7 @@ def test_full(progress, experimental):
         ]
     )
     check_image_file(root_folder, os.path.join(root_folder, "final.png"), "all-2")
+    shutil.rmtree(root_folder)
 
 
 # @pytest.mark.skip(reason='for test')
@@ -329,7 +330,6 @@ def test_credit_card_full():
         os.makedirs(root_folder)
     config = {
         "args": {
-            "assisted_split": False,
             "level": True,
             "append_credit_card": True,
         },
@@ -360,6 +360,7 @@ def test_credit_card_full():
         ]
     )
     check_image_file(root_folder, os.path.join(root_folder, "final.png"), "credit-card-1")
+    shutil.rmtree(root_folder)
 
 
 # @pytest.mark.skip(reason='for test')
@@ -371,9 +372,7 @@ def test_empty():
         os.makedirs(root_folder)
     config = {
         "args": {
-            "assisted_split": False,
             "level": True,
-            "append_credit_card": False,
         },
         "destination": os.path.join(root_folder, "final.pdf"),
     }
@@ -385,3 +384,21 @@ def test_empty():
     step = process.transform(config, step, "/tmp/test-config.yaml", root_folder)
     assert len(step["sources"]) == 0
     assert step["name"] == "finalise"
+    shutil.rmtree(root_folder)
+
+
+# @pytest.mark.skip(reason='for test')
+@pytest.mark.parametrize("test,args", [("600", {"dpi": 600})])
+def test_custom_process(test, args):
+    init_test()
+    root_folder = f"/results/600"
+    if not os.path.exists(root_folder):
+        os.makedirs(root_folder)
+    config = {
+        "args": args,
+    }
+    step = {"sources": [os.path.join(os.path.dirname(__file__), f"{test}.png")]}
+    step = process.transform(config, step, "/tmp/test-config.yaml", root_folder)
+    assert len(step["sources"]) == 1
+    check_image_file(root_folder, step["sources"][0], test)
+    shutil.rmtree(root_folder)