Add an inverse function to construct intrinsic matrix

eigenvivek · Feb 19, 2024 · 949428d · 949428d
1 parent 45d3a23
commit 949428d
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Showing 3 changed files with 54 additions and 9 deletions.
diff --git a/diffdrr/_modidx.py b/diffdrr/_modidx.py
@@ -120,6 +120,7 @@
                                    'diffdrr.renderers._get_voxel': ('api/renderers.html#_get_voxel', 'diffdrr/renderers.py')},
             'diffdrr.utils': { 'diffdrr.utils.get_focal_length': ('api/utils.html#get_focal_length', 'diffdrr/utils.py'),
                                'diffdrr.utils.get_principal_point': ('api/utils.html#get_principal_point', 'diffdrr/utils.py'),
+                               'diffdrr.utils.make_intrinsic_matrix': ('api/utils.html#make_intrinsic_matrix', 'diffdrr/utils.py'),
                                'diffdrr.utils.parse_intrinsic_matrix': ('api/utils.html#parse_intrinsic_matrix', 'diffdrr/utils.py')},
             'diffdrr.visualization': { 'diffdrr.visualization._make_camera_frustum_mesh': ( 'api/visualization.html#_make_camera_frustum_mesh',
                                                                                             'diffdrr/visualization.py'),

diff --git a/diffdrr/utils.py b/diffdrr/utils.py
@@ -1,7 +1,7 @@
 # AUTOGENERATED! DO NOT EDIT! File to edit: ../notebooks/api/07_utils.ipynb.
 
 # %% auto 0
-__all__ = ['get_focal_length', 'get_principal_point', 'parse_intrinsic_matrix']
+__all__ = ['get_focal_length', 'get_principal_point', 'parse_intrinsic_matrix', 'make_intrinsic_matrix']
 
 # %% ../notebooks/api/07_utils.ipynb 4
 def get_focal_length(
@@ -16,8 +16,8 @@ def get_focal_length(
 # %% ../notebooks/api/07_utils.ipynb 5
 def get_principal_point(
     intrinsic,  # Intrinsic matrix (3 x 3 tensor)
-    height: int,  # Y-direction length
-    width: int,  # X-direction length
+    height: int,  # Y-direction length (in units pixels)
+    width: int,  # X-direction length (in units pixels)
     delx: float,  # X-direction spacing (in units length)
     dely: float,  # Y-direction spacing (in units length)
 ):
@@ -28,11 +28,29 @@ def get_principal_point(
 # %% ../notebooks/api/07_utils.ipynb 6
 def parse_intrinsic_matrix(
     intrinsic,  # Intrinsic matrix (3 x 3 tensor)
-    height: int,  # Y-direction length
-    width: int,  # X-direction length
+    height: int,  # Y-direction length (in units pixels)
+    width: int,  # X-direction length (in units pixels)
     delx: float,  # X-direction spacing (in units length)
     dely: float,  # Y-direction spacing (in units length)
 ):
     focal_length = get_focal_length(intrinsic, delx, dely)
     x0, y0 = get_principal_point(intrinsic, height, width, delx, dely)
     return focal_length, x0, y0
+
+# %% ../notebooks/api/07_utils.ipynb 7
+def make_intrinsic_matrix(
+    sdr: float,  # Source-to-detector radius (in units length)
+    height: int,  # Y-direction length (in units pixels)
+    width: int,  # X-direction length (in units pixels)
+    delx: float,  # X-direction spacing (in units length)
+    dely: float,  # Y-direction spacing (in units length)
+    x0: float = 0.0,  # Principal point x-coordinate (in units length)
+    y0: float = 0.0,  # Principal point y-coordinate (in units length)
+):
+    return torch.tensor(
+        [
+            [-2 * sdr / delx, 0.0, height / 2 - x0 / delx],
+            [0.0, -2 * sdr / dely, width / 2 - y0 / dely],
+            [0.0, 0.0, 1.0],
+        ]
+    )
diff --git a/notebooks/api/07_utils.ipynb b/notebooks/api/07_utils.ipynb
@@ -73,8 +73,8 @@
     "#| export\n",
     "def get_principal_point(\n",
     "    intrinsic,  # Intrinsic matrix (3 x 3 tensor)\n",
-    "    height: int,  # Y-direction length\n",
-    "    width: int,  # X-direction length\n",
+    "    height: int,  # Y-direction length (in units pixels)\n",
+    "    width: int,  # X-direction length (in units pixels)\n",
     "    delx: float,  # X-direction spacing (in units length)\n",
     "    dely: float,  # Y-direction spacing (in units length)\n",
     "):\n",
@@ -93,8 +93,8 @@
     "#| export\n",
     "def parse_intrinsic_matrix(\n",
     "    intrinsic,  # Intrinsic matrix (3 x 3 tensor)\n",
-    "    height: int,  # Y-direction length\n",
-    "    width: int,  # X-direction length\n",
+    "    height: int,  # Y-direction length (in units pixels)\n",
+    "    width: int,  # X-direction length (in units pixels)\n",
     "    delx: float,  # X-direction spacing (in units length)\n",
     "    dely: float,  # Y-direction spacing (in units length)\n",
     "):\n",
@@ -103,6 +103,32 @@
     "    return focal_length, x0, y0"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "9119195d-bedf-4076-a7c0-87dd359c2b35",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "#| export\n",
+    "def make_intrinsic_matrix(\n",
+    "    sdr: float,  # Source-to-detector radius (in units length)\n",
+    "    height: int,  # Y-direction length (in units pixels)\n",
+    "    width: int,  # X-direction length (in units pixels)\n",
+    "    delx: float,  # X-direction spacing (in units length)\n",
+    "    dely: float,  # Y-direction spacing (in units length)\n",
+    "    x0: float = 0.0,  # Principal point x-coordinate (in units length)\n",
+    "    y0: float = 0.0,  # Principal point y-coordinate (in units length)\n",
+    "):\n",
+    "    return torch.tensor(\n",
+    "        [\n",
+    "            [-2 * sdr / delx, 0.0, height / 2 - x0 / delx],\n",
+    "            [0.0, -2 * sdr / dely, width / 2 - y0 / dely],\n",
+    "            [0.0, 0.0, 1.0],\n",
+    "        ]\n",
+    "    )"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,