diff --git a/src/api.rs b/src/api.rs
index 6a58820..42ada33 100644
--- a/src/api.rs
+++ b/src/api.rs
@@ -1,5 +1,5 @@
 use crate::display::EInkPanel;
-use crate::imageproc::{DitherMethod, DitherPalette, DitheredImage};
+use crate::dither::{DitherMethod, DitherPalette, DitheredImage};
 use axum::async_trait;
 use axum::extract::{FromRequest, Multipart, State};
 use axum::http::{header, StatusCode};
@@ -153,7 +153,11 @@ async fn set_image(
     img_req: ImageRequest,
 ) -> Result<impl IntoResponse, AppError> {
     // FIXME: resize image to 800x480 to match the eink panel.
-    let mut buf = DitheredImage::new(img_req.image.width(), img_req.image.height(), img_req.palette.value().to_vec());
+    let mut buf = DitheredImage::new(
+        img_req.image.width(),
+        img_req.image.height(),
+        img_req.palette.value().to_vec(),
+    );
     {
         let mut dither = img_req.dither_method.get_ditherer();
         dither.dither(&img_req.image, &mut buf);
@@ -168,7 +172,11 @@ async fn set_image(
 /// generates a dithered image based on the given image and the dithering parameters.
 /// Can be used to see how the dithering and palette choices affect the result.
 async fn preview_image(img_req: ImageRequest) -> Result<impl IntoResponse, AppError> {
-    let mut buf = DitheredImage::new(img_req.image.width(), img_req.image.height(), img_req.palette.value().to_vec());
+    let mut buf = DitheredImage::new(
+        img_req.image.width(),
+        img_req.image.height(),
+        img_req.palette.value().to_vec(),
+    );
     {
         let mut dither = img_req.dither_method.get_ditherer();
         dither.dither(&img_req.image, &mut buf);
diff --git a/src/display.rs b/src/display.rs
index 08cc5b8..79121f6 100644
--- a/src/display.rs
+++ b/src/display.rs
@@ -8,7 +8,7 @@ use tracing::{debug, warn};
 use anyhow::Result;
 use linux_embedded_hal::gpio_cdev::{Chip, LineRequestFlags};
 
-use crate::imageproc::DitheredImage;
+use crate::dither::DitheredImage;
 
 pub trait EInkPanel {
     fn display(&mut self, buf: &DitheredImage) -> Result<()>;
@@ -83,7 +83,7 @@ pub struct FakeEInk();
 impl EInkPanel for FakeEInk {
     fn display(&mut self, img: &DitheredImage) -> Result<()> {
         warn!("Fake display was called: saving to display.bmp");
-        img.into_rgbimage().save("display.bmp");
+        img.into_rgbimage().save("display.bmp")?;
 
         Ok(())
     }
diff --git a/src/imageproc.rs b/src/dither.rs
similarity index 98%
rename from src/imageproc.rs
rename to src/dither.rs
index 40da8fc..ee6cbbe 100644
--- a/src/imageproc.rs
+++ b/src/dither.rs
@@ -91,6 +91,10 @@ impl DitheredImage {
     }
 
     /// Convert the index-based image back into an RGB image using the color palette.
+    ///
+    /// # Panics
+    /// May panic if the given palette is somehow not the one used to actually dither, and the
+    /// image has color indexes that are out of bounds of the palette.
     #[must_use]
     pub fn into_rgbimage(&self) -> RgbImage {
         RgbImage::from_fn(self.buf.width(), self.buf.height(), |x, y| {
diff --git a/src/main.rs b/src/main.rs
index 4156b70..8d8df80 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,10 +1,10 @@
 pub mod api;
 pub mod display;
 pub mod errors;
-pub mod imageproc;
+pub mod dither;
 
 use crate::display::{EInkPanel, FakeEInk, Wrapper};
-use crate::imageproc::{DitherMethod, DitheredImage};
+use crate::dither::{DitherMethod, DitheredImage};
 use clap::{Parser, Subcommand};
 use image::RgbImage;
 use tracing::{error, info};