Implement landmark plot function

src/falign/plot.py

@@ -0,0 +1,25 @@
+from pathlib import Path
+
+from numpy.typing import NDArray
+
+from skimage.io import imsave
+
+
+def imsave_with_landmarks(
+    path: Path,
+    image: NDArray, landmarks: NDArray,
+    size: int = 1,
+) -> None:
+    """
+    Save image with landmarks.
+    Args:
+        path: The path to save the image.
+        image: The image array.
+        landmarks: The landmarks array of shape (N, 2).
+    """
+
+    for landmark in landmarks:
+        x, y = int(landmark[0]), int(landmark[1])
+        image[(y-size):(y+size+1), (x-size):(x+size+1)] = 255
+
+    imsave(path, image)

test/test_falign/test_landmarks.py

@@ -1,8 +1,9 @@
 from pathlib import Path
 
-from matplotlib import pyplot
+from skimage.io import imread
 
 from falign.landmarks import get_landmarks
+from falign.plot import imsave_with_landmarks
 
 
 def test_get_landmarks():
@@ -12,11 +13,8 @@ def test_get_landmarks():
 
     assert landmarks.shape == (68, 2)
 
-    fig, ax = pyplot.subplots()
-    ax.imshow(pyplot.imread(path_image))
-    ax.scatter(landmarks[:, 0], landmarks[:, 1], s=1)
-    ax.axis("off")
-    ax.margins(0)
-    ax.set_aspect("equal")
-    fig.tight_layout(pad=0)
-    fig.savefig(dir_gallery / "test_get_landmarks.jpg")
+    imsave_with_landmarks(
+        dir_gallery / "test_get_landmarks.jpg",
+        imread(path_image), landmarks,
+        size=5
+    )