fix camera intrinsics

scene/cameras.py

@@ -15,7 +15,7 @@
 from utils.graphics_utils import getWorld2View2, getProjectionMatrix
 
 class Camera(nn.Module):
-    def __init__(self, colmap_id, R, T, FoVx, FoVy, image, gt_alpha_mask,
+    def __init__(self, colmap_id, R, T, FoVx, FoVy, cx, cy, image, gt_alpha_mask,
                  image_name, uid,
                  trans=np.array([0.0, 0.0, 0.0]), scale=1.0, data_device = "cuda"
                  ):
@@ -27,6 +27,8 @@ def __init__(self, colmap_id, R, T, FoVx, FoVy, image, gt_alpha_mask,
         self.T = T
         self.FoVx = FoVx
         self.FoVy = FoVy
+        self.cx = cx
+        self.cy = cy
         self.image_name = image_name
 
         try:
@@ -52,7 +54,9 @@ def __init__(self, colmap_id, R, T, FoVx, FoVy, image, gt_alpha_mask,
         self.scale = scale
 
         self.world_view_transform = torch.tensor(getWorld2View2(R, T, trans, scale)).transpose(0, 1).cuda()
-        self.projection_matrix = getProjectionMatrix(znear=self.znear, zfar=self.zfar, fovX=self.FoVx, fovY=self.FoVy).transpose(0,1).cuda()
+        self.projection_matrix = getProjectionMatrix(znear=self.znear, zfar=self.zfar,
+                                                     fovX=self.FoVx, fovY=self.FoVy,
+                                                     cx=self.cx, cy=self.cy).transpose(0, 1).cuda()
         self.full_proj_transform = (self.world_view_transform.unsqueeze(0).bmm(self.projection_matrix.unsqueeze(0))).squeeze(0)
         self.camera_center = self.world_view_transform.inverse()[3, :3]
 

scene/dataset_readers.py

@@ -29,6 +29,8 @@ class CameraInfo(NamedTuple):
     T: np.array
     FovY: np.array
     FovX: np.array
+    cx: np.array
+    cy: np.array
     image: np.array
     image_path: str
     image_name: str
@@ -84,21 +86,28 @@ def readColmapCameras(cam_extrinsics, cam_intrinsics, images_folder):
 
         if intr.model=="SIMPLE_PINHOLE":
             focal_length_x = intr.params[0]
+            cx = intr.params[1]
+            cy = intr.params[2]
             FovY = focal2fov(focal_length_x, height)
             FovX = focal2fov(focal_length_x, width)
         elif intr.model=="PINHOLE":
+            cx = intr.params[2]
+            cy = intr.params[3]
             focal_length_x = intr.params[0]
             focal_length_y = intr.params[1]
             FovY = focal2fov(focal_length_y, height)
             FovX = focal2fov(focal_length_x, width)
         else:
             assert False, "Colmap camera model not handled: only undistorted datasets (PINHOLE or SIMPLE_PINHOLE cameras) supported!"
 
+        cx = (cx - width / 2) / width * 2
+        cy = (cy - height / 2) / height * 2
+
         image_path = os.path.join(images_folder, os.path.basename(extr.name))
         image_name = os.path.basename(image_path).split(".")[0]
         image = Image.open(image_path)
 
-        cam_info = CameraInfo(uid=uid, R=R, T=T, FovY=FovY, FovX=FovX, image=image,
+        cam_info = CameraInfo(uid=uid, R=R, T=T, FovY=FovY, FovX=FovX, cx=cx, cy=cy, image=image,
                               image_path=image_path, image_name=image_name, width=width, height=height)
         cam_infos.append(cam_info)
     sys.stdout.write('\n')

utils/camera_utils.py

@@ -47,7 +47,8 @@ def loadCam(args, id, cam_info, resolution_scale):
         loaded_mask = resized_image_rgb[3:4, ...]
 
     return Camera(colmap_id=cam_info.uid, R=cam_info.R, T=cam_info.T, 
-                  FoVx=cam_info.FovX, FoVy=cam_info.FovY, 
+                  FoVx=cam_info.FovX, FoVy=cam_info.FovY,
+                  cx=cam_info.cx, cy=cam_info.cy,
                   image=gt_image, gt_alpha_mask=loaded_mask,
                   image_name=cam_info.image_name, uid=id, data_device=args.data_device)
 

utils/graphics_utils.py

@@ -48,7 +48,7 @@ def getWorld2View2(R, t, translate=np.array([.0, .0, .0]), scale=1.0):
     Rt = np.linalg.inv(C2W)
     return np.float32(Rt)
 
-def getProjectionMatrix(znear, zfar, fovX, fovY):
+def getProjectionMatrix(znear, zfar, fovX, fovY, cx, cy):
     tanHalfFovY = math.tan((fovY / 2))
     tanHalfFovX = math.tan((fovX / 2))
 
@@ -63,8 +63,8 @@ def getProjectionMatrix(znear, zfar, fovX, fovY):
 
     P[0, 0] = 2.0 * znear / (right - left)
     P[1, 1] = 2.0 * znear / (top - bottom)
-    P[0, 2] = (right + left) / (right - left)
-    P[1, 2] = (top + bottom) / (top - bottom)
+    P[0, 2] = cx
+    P[1, 2] = cy
     P[3, 2] = z_sign
     P[2, 2] = z_sign * zfar / (zfar - znear)
     P[2, 3] = -(zfar * znear) / (zfar - znear)