Simplify layout proxy methods

src/decoder/image.rs

@@ -606,20 +606,6 @@ impl Image {
         }
     }
 
-    /// Get the layout for each output plane (i.e. one plane for non-planar tiff).
-    pub(crate) fn preferred_output_layout(&self) -> TiffResult<PlaneLayout> {
-        let Image { width, height, .. } = *self;
-        self.preferred_output_layout_for(width, height)
-    }
-
-    pub(crate) fn preferred_output_layout_for(
-        &self,
-        width: u32,
-        height: u32,
-    ) -> TiffResult<PlaneLayout> {
-        self.readout_for_size(width, height)?.to_plane_layout()
-    }
-
     pub(crate) fn readout_for_image(&self) -> TiffResult<ReadoutLayout> {
         let Image { width, height, .. } = *self;
         self.readout_for_size(width, height)

src/decoder/mod.rs

@@ -1136,9 +1136,12 @@ impl<R: Read + Seek> Decoder<R> {
         }
 
         let data_dims = self.image().chunk_data_dimensions(chunk_index)?;
+
         let layout = self
             .image()
-            .preferred_output_layout_for(data_dims.0, data_dims.1)?;
+            .readout_for_size(data_dims.0, data_dims.1)?
+            .to_plane_layout()?;
+
         Ok(BufferLayoutPreference::from_planes(&layout))
     }
 
@@ -1212,7 +1215,7 @@ impl<R: Read + Seek> Decoder<R> {
     /// indicate the layout needed to read the first data plane. This will be fixed in a future
     /// major version of `tiff`.
     pub fn image_buffer_layout(&mut self) -> TiffResult<BufferLayoutPreference> {
-        let layout = self.image().preferred_output_layout()?;
+        let layout = self.image().readout_for_image()?.to_plane_layout()?;
         Ok(BufferLayoutPreference::from_planes(&layout))
     }