FBP: removed duplicated and deprecated code

Signed-off-by: Nicola VIGANÒ <nicola.vigano@cea.fr>

corrct/_projector_backends.py

@@ -245,22 +245,6 @@ def bp(self, prj: NDArray, angle_ind: Optional[int] = None) -> NDArray:
             The angle index to foward project. The default is None.
         """
 
-    @abstractmethod
-    def fbp(self, prj: NDArray, fbp_filter: Union[str, NDArray], pad_mode: str) -> NDArray:
-        """Apply FBP.
-
-        Filtered back-projection interface. Derived backends need to implement this method.
-
-        Parameters
-        ----------
-        prj : NDArray
-            The sinogram or stack of sinograms.
-        fbp_filter : str | NDArray, optional
-            The filter to use in the filtered back-projection.
-        pad_mode: str, optional
-            The padding mode to use for the linear convolution.
-        """
-
 
 class ProjectorBackendSKimage(ProjectorBackend):
     """Projector backend based on scikit-image."""
@@ -372,40 +356,6 @@ def bp(self, prj: NDArray, angle_ind: Optional[int] = None) -> NDArray:
             vol = skt.iradon(prj[:, np.newaxis], self.angles_w_deg[angle_ind : angle_ind + 1 :], **bpj_size, **filter_name)
         return vol * 2 / np.pi
 
-    def fbp(self, prj: NDArray, fbp_filter: Union[str, ArrayLike], pad_mode: str) -> NDArray:
-        """Apply filtered back-projection of a sinogram or stack of sinograms.
-
-        Parameters
-        ----------
-        prj : NDArray
-            The sinogram or stack of sinograms.
-        fbp_filter : str | ArrayLike, optional
-            The filter to use in the filtered back-projection.
-        pad_mode: str, optional
-            The padding mode to use for the linear convolution.
-
-        Returns
-        -------
-        vol : NDArray
-            The reconstructed volume.
-        """
-        if pad_mode.lower() != "constant":
-            raise ValueError(f"Argument 'pad_mode' only supports 'constant', while {pad_mode.lower()} was given.")
-        if not isinstance(fbp_filter, str):
-            raise ValueError(f"Custom filters not supported in the scikit-image backend.")
-
-        filter_name = self._set_filter_name(fbp_filter.lower())
-        bpj_size = self._set_bpj_size(self.vol_shape_zxy[-1])
-        if len(prj.shape) > 2:
-            num_lines = prj.shape[1]
-            vol = np.empty([num_lines, *self.vol_shape_zxy], dtype=prj.dtype)
-
-            for ii_v in range(num_lines):
-                vol[ii_v, ...] = skt.iradon(prj[ii_v, ...].transpose(), self.angles_w_deg, **bpj_size, **filter_name)
-            return vol
-        else:
-            return skt.iradon(prj.transpose(), self.angles_w_deg, **bpj_size, **filter_name)
-
 
 class ProjectorBackendASTRA(ProjectorBackend):
     """Projector backend based on astra-toolbox."""
@@ -699,45 +649,6 @@ def bp(self, prj: NDArray, angle_ind: Optional[int] = None) -> NDArray:
 
         return vol
 
-    def fbp(self, prj: NDArray, fbp_filter: Union[str, NDArray, filters.Filter], pad_mode: str) -> NDArray:
-        """Apply filtered back-projection of a sinogram or stack of sinograms.
-
-        Parameters
-        ----------
-        prj : NDArray
-            The sinogram or stack of sinograms.
-        fbp_filter : str | NDArray | filtering.Filter, optional
-            The filter to use in the filtered back-projection.
-        pad_mode: str, optional
-            The padding mode to use for the linear convolution.
-
-        Returns
-        -------
-        vol : NDArray
-            The reconstructed volume.
-        """
-        if isinstance(fbp_filter, str):
-            local_filter = filters.FilterFBP(filter_name=fbp_filter)
-        elif isinstance(fbp_filter, np.ndarray):
-            local_filter = filters.FilterCustom(fbp_filter)
-        else:
-            local_filter = fbp_filter
-        local_filter.pad_mode = pad_mode
-
-        prj_f = local_filter(prj)
-
-        if self.vol_geom.is_3D() or len(prj.shape) == 2:
-            return self.bp(prj_f)
-        else:
-            num_lines = prj.shape[-3]
-            vols = []
-
-            for ii_v in range(num_lines):
-                prj_v = np.ascontiguousarray(prj_f[ii_v, :, :])
-                vols.append(self.bp(prj_v))
-
-            return np.ascontiguousarray(np.stack(vols, axis=0))
-
 
 class ProjectorBackendDirectASTRA(ProjectorBackendASTRA):
     """Experimental astra-toolbox functions projector."""

corrct/projectors.py

@@ -345,37 +345,6 @@ def bp(self, prj_vwu: NDArray) -> NDArray:
             prj_vwu = self.psf_vwu.T(prj_vwu)
         return self.projector_backend.bp(prj_vwu)
 
-    def fbp(self, projs: NDArray, fbp_filter: Union[str, Callable] = "ramp", pad_mode: str = "constant") -> NDArray:
-        """
-        Compute the filtered back-projection of the projection data to the volume.
-
-        The data could either be a sinogram, or a stack of sinograms.
-
-        Parameters
-        ----------
-        projs : NDArray
-            The projection data to back-project.
-        fbp_filter : str | Callable, optional
-            The FBP filter to use. The default is "ramp".
-        pad_mode: str, optional
-            The padding mode to use for the linear convolution. The default is "constant".
-
-        Raises
-        ------
-        ValueError
-            When trying to use fbp with a 3D projection geometry.
-
-        Returns
-        -------
-        NDArray
-            The FBP reconstructed volume.
-        """
-        if isinstance(fbp_filter, str):
-            return self.projector_backend.fbp(projs, fbp_filter=fbp_filter, pad_mode=pad_mode)
-        else:
-            projs = fbp_filter(projs, self)
-            return self.bp(projs) / self.angles_rot_rad.size
-
 
 class ProjectorAttenuationXRF(ProjectorUncorrected):
     """