Fix some warnings (#488)

examples/color_effects.rs

@@ -39,7 +39,7 @@ fn main() {
     // Load a image::DynamicImage and convert it to a image::GrayImage
     let image = open(path)
         .expect(&format!("Could not load image at {:?}", path))
-        .to_luma();
+        .to_luma8();
 
     let blue = Rgb([0u8, 0u8, 255u8]);
 

examples/display_image.rs

@@ -19,7 +19,7 @@ fn main() {
 
     let image = image::open(&image_path)
         .expect("No image found at provided path")
-        .to_rgba();
+        .to_rgba8();
 
     display_image("", &image, 500, 500);
 }

examples/display_multiple_images.rs

@@ -26,10 +26,10 @@ fn main() {
 
     let first_image = image::open(&first_image_path)
         .expect("No image found at provided path")
-        .to_rgba();
+        .to_rgba8();
     let second_image = image::open(&second_image_path)
         .expect("No image found at provided path")
-        .to_rgba();
+        .to_rgba8();
 
     display_multiple_images("", &vec![&first_image, &second_image], 500, 500);
 }

examples/gradients.rs

@@ -51,7 +51,7 @@ fn main() {
     // Load image and convert to grayscale
     let input_image = open(input_path)
         .expect(&format!("Could not load image at {:?}", input_path))
-        .to_luma();
+        .to_luma8();
 
     // Save grayscale image in output directory
     let gray_path = output_dir.join("grey.png");

examples/hog.rs

@@ -9,7 +9,7 @@ fn create_hog_image(input: &Path, signed: bool) {
     // Load a image::DynamicImage and convert it to a image::GrayImage
     let image = open(input)
         .expect(&format!("Could not load image at {:?}", input))
-        .to_luma();
+        .to_luma8();
 
     // We're not going to do anything interesting with the block sizes here - they're
     // only relevant when combining and normalising per-cell histograms, and in this

examples/hough.rs

@@ -33,7 +33,7 @@ fn main() {
     // Load image and convert to grayscale
     let input_image = open(input_path)
         .expect(&format!("Could not load image at {:?}", input_path))
-        .to_luma();
+        .to_luma8();
 
     // Save grayscale image in output directory
     let gray_path = output_dir.join("grey.png");

examples/projection.rs

@@ -30,7 +30,7 @@ fn main() -> ImageResult<()> {
 
     let image = open(input_path)
         .expect(&format!("Could not load image at {:?}", input_path))
-        .to_rgb();
+        .to_rgb8();
 
     let translate = Projection::translate(90.0, 10.0);
     warp(

examples/seam_carving.rs

@@ -32,7 +32,7 @@ fn main() {
     // Load image and convert to grayscale
     let input_image = open(input_path)
         .expect(&format!("Could not load image at {:?}", input_path))
-        .to_rgb();
+        .to_rgb8();
 
     // Save original image in output directory
     let original_path = output_dir.join("original.png");

examples/template_matching.rs

@@ -131,7 +131,7 @@ fn main() {
     // Load image and convert to grayscale
     let image = open(input_path)
         .expect(&format!("Could not load image at {:?}", input_path))
-        .to_luma();
+        .to_luma8();
 
     // Extract the requested image sub-region to use as the template
     let template = copy_sub_image(

src/drawing/polygon.rs

@@ -58,7 +58,7 @@ where
     y_min = max(0, min(y_min, height as i32 - 1));
     y_max = max(0, min(y_max, height as i32 - 1));
 
-    let mut closed: Vec<Point<i32>> = poly.iter().copied().collect();
+    let mut closed: Vec<Point<i32>> = poly.to_vec();
     closed.push(poly[0]);
 
     let edges: Vec<&[Point<i32>]> = closed.windows(2).collect();

src/edges.rs

@@ -69,13 +69,13 @@ fn non_maximum_suppression(
                 angle += 180.0
             }
             // Clamp angle.
-            let clamped_angle = if angle >= 157.5 || angle < 22.5 {
+            let clamped_angle = if !(22.5..157.5).contains(&angle) {
                 0
-            } else if angle >= 22.5 && angle < 67.5 {
+            } else if (22.5..67.5).contains(&angle) {
                 45
-            } else if angle >= 67.5 && angle < 112.5 {
+            } else if (67.5..112.5).contains(&angle) {
                 90
-            } else if angle >= 112.5 && angle < 157.5 {
+            } else if (112.5..157.5).contains(&angle) {
                 135
             } else {
                 unreachable!()

src/filter/median.rs

@@ -120,16 +120,16 @@ where
     let rx = x_radius as i32;
     let ry = y_radius as i32;
 
-    let mut hist = initialise_histogram_for_top_left_pixel(&image, x_radius, y_radius);
-    slide_down_column(&mut hist, &image, &mut out, 0, rx, ry);
+    let mut hist = initialise_histogram_for_top_left_pixel(image, x_radius, y_radius);
+    slide_down_column(&mut hist, image, &mut out, 0, rx, ry);
 
     for x in 1..width {
         if x % 2 == 0 {
-            slide_right(&mut hist, &image, x, 0, rx, ry);
-            slide_down_column(&mut hist, &image, &mut out, x, rx, ry);
+            slide_right(&mut hist, image, x, 0, rx, ry);
+            slide_down_column(&mut hist, image, &mut out, x, rx, ry);
         } else {
-            slide_right(&mut hist, &image, x, height - 1, rx, ry);
-            slide_up_column(&mut hist, &image, &mut out, x, rx, ry);
+            slide_right(&mut hist, image, x, height - 1, rx, ry);
+            slide_up_column(&mut hist, image, &mut out, x, rx, ry);
         }
     }
     out

src/filter/mod.rs

@@ -58,7 +58,7 @@ pub fn bilateral_filter(
 ) -> Image<Luma<u8>> {
     /// Un-normalized Gaussian weights for look-up tables.
     fn gaussian_weight(x: f32, sigma_squared: f32) -> f32 {
-        return (-0.5 * x.powi(2) / sigma_squared).exp();
+        (-0.5 * x.powi(2) / sigma_squared).exp()
     }
 
     /// Effectively a meshgrid command with flattened outputs.
@@ -79,7 +79,7 @@ pub fn bilateral_filter(
         for i in window_range {
             rr.append(&mut vec![i; (window_size + 1) as usize]);
         }
-        return (rr, cc);
+        (rr, cc)
     }
 
     /// Create look-up table of Gaussian weights for color dimension.

src/geometry.rs

@@ -75,7 +75,7 @@ pub fn min_area_rect<T>(points: &[Point<T>]) -> [Point<T>; 4]
 where
     T: NumCast + Copy + Ord,
 {
-    let hull = convex_hull(&points);
+    let hull = convex_hull(points);
     match hull.len() {
         0 => panic!("no points are defined"),
         1 => [hull[0]; 4],

src/hog.rs

@@ -209,8 +209,8 @@ fn hog_descriptor_from_hist_grid(grid: View3d<'_, f32>, spec: HogSpec) -> Vec<f3
 
         for by in 0..spec.blocks_high {
             for bx in 0..spec.blocks_wide {
-                let mut block_data = block_view.inner_slice_mut(bx, by);
-                let mut block = View3d::from_raw(&mut block_data, spec.block_internal_lengths());
+                let block_data = block_view.inner_slice_mut(bx, by);
+                let mut block = View3d::from_raw(block_data, spec.block_internal_lengths());
 
                 for iy in 0..spec.options.block_side {
                     let cy = by * spec.options.block_stride + iy;

src/seam_carving.rs

@@ -54,7 +54,7 @@ where
         "Cannot find seams if image width is < 2"
     );
 
-    let mut gradients = sobel_gradient_map(&image, |p| {
+    let mut gradients = sobel_gradient_map(image, |p| {
         let gradient_sum: u16 = p.channels().iter().sum();
         let gradient_mean: u16 = gradient_sum / P::CHANNEL_COUNT as u16;
         Luma([gradient_mean as u32])

src/stats.rs

@@ -89,7 +89,7 @@ where
 pub fn percentile(image: &GrayImage, p: u8) -> u8 {
     assert!(p <= 100, "requested percentile must be <= 100");
 
-    let cum_hist = cumulative_histogram(&image).channels[0];
+    let cum_hist = cumulative_histogram(image).channels[0];
     let total = cum_hist[255] as u64;
 
     for i in 0..256 {

src/template_matching.rs

@@ -56,12 +56,12 @@ pub fn match_template(
     MatchTemplateMethod::SumOfSquaredErrorsNormalized
     | MatchTemplateMethod::CrossCorrelationNormalized };
     let image_squared_integral = if should_normalize {
-        Some(integral_squared_image(&image))
+        Some(integral_squared_image(image))
     } else {
         None
     };
     let template_squared_sum = if should_normalize {
-        Some(sum_squares(&template))
+        Some(sum_squares(template))
     } else {
         None
     };

src/union_find.rs

@@ -16,7 +16,7 @@ impl DisjointSetForest {
     /// Constructs forest of singletons with count elements.
     pub fn new(count: usize) -> DisjointSetForest {
         let parent: Vec<usize> = (0..count).collect();
-        let tree_size = vec![1 as usize; count];
+        let tree_size = vec![1_usize; count];
         DisjointSetForest {
             count,
             parent,

src/utils.rs

@@ -489,12 +489,12 @@ where
     let mut err = "pixels do not match.\n".to_owned();
 
     // Find the boundaries of the region containing diffs
-    let top_left = diffs.iter().fold((u32::MAX, u32::MAX), |acc, ref d| {
+    let top_left = diffs.iter().fold((u32::MAX, u32::MAX), |acc, d| {
         (acc.0.min(d.x), acc.1.min(d.y))
     });
     let bottom_right = diffs
         .iter()
-        .fold((0, 0), |acc, ref d| (acc.0.max(d.x), acc.1.max(d.y)));
+        .fold((0, 0), |acc, d| (acc.0.max(d.x), acc.1.max(d.y)));
 
     // If all the diffs are contained in a small region of the image then render all of this
     // region, with a small margin.
@@ -506,7 +506,7 @@ where
 
         let diff_locations = diffs.iter().map(|d| (d.x, d.y)).collect::<HashSet<_>>();
 
-        err.push_str(&colored(&"Actual:", Color::Red));
+        err.push_str(&colored("Actual:", Color::Red));
         let actual_rendered = render_image_region(actual, left, top, right, bottom, |x, y| {
             if diff_locations.contains(&(x, y)) {
                 Color::Red
@@ -516,7 +516,7 @@ where
         });
         err.push_str(&actual_rendered);
 
-        err.push_str(&colored(&"Expected:", Color::Green));
+        err.push_str(&colored("Expected:", Color::Green));
         let expected_rendered = render_image_region(expected, left, top, right, bottom, |x, y| {
             if diff_locations.contains(&(x, y)) {
                 Color::Green

tests/regression.rs

@@ -46,19 +46,19 @@ trait FromDynamic {
 
 impl FromDynamic for GrayImage {
     fn from_dynamic(image: &DynamicImage) -> Self {
-        image.to_luma()
+        image.to_luma8()
     }
 }
 
 impl FromDynamic for RgbImage {
     fn from_dynamic(image: &DynamicImage) -> Self {
-        image.to_rgb()
+        image.to_rgb8()
     }
 }
 
 impl FromDynamic for RgbaImage {
     fn from_dynamic(image: &DynamicImage) -> Self {
-        image.to_rgba()
+        image.to_rgba8()
     }
 }
 
@@ -323,7 +323,7 @@ fn test_sharpen_gaussian() {
 #[test]
 fn test_match_histograms() {
     fn match_to_zebra_histogram(image: &GrayImage) -> GrayImage {
-        let zebra = load_image_or_panic(Path::new(INPUT_DIR).join("zebra.png")).to_luma();
+        let zebra = load_image_or_panic(Path::new(INPUT_DIR).join("zebra.png")).to_luma8();
         imageproc::contrast::match_histogram(image, &zebra)
     }
     compare_to_truth(