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-rw-r--r--vendor/image/src/imageops/affine.rs410
-rw-r--r--vendor/image/src/imageops/colorops.rs646
-rw-r--r--vendor/image/src/imageops/mod.rs485
-rw-r--r--vendor/image/src/imageops/sample.rs1228
4 files changed, 2769 insertions, 0 deletions
diff --git a/vendor/image/src/imageops/affine.rs b/vendor/image/src/imageops/affine.rs
new file mode 100644
index 0000000..548381c
--- /dev/null
+++ b/vendor/image/src/imageops/affine.rs
@@ -0,0 +1,410 @@
+//! Functions for performing affine transformations.
+
+use crate::error::{ImageError, ParameterError, ParameterErrorKind};
+use crate::image::{GenericImage, GenericImageView};
+use crate::traits::Pixel;
+use crate::ImageBuffer;
+
+/// Rotate an image 90 degrees clockwise.
+pub fn rotate90<I: GenericImageView>(
+ image: &I,
+) -> ImageBuffer<I::Pixel, Vec<<I::Pixel as Pixel>::Subpixel>>
+where
+ I::Pixel: 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(height, width);
+ let _ = rotate90_in(image, &mut out);
+ out
+}
+
+/// Rotate an image 180 degrees clockwise.
+pub fn rotate180<I: GenericImageView>(
+ image: &I,
+) -> ImageBuffer<I::Pixel, Vec<<I::Pixel as Pixel>::Subpixel>>
+where
+ I::Pixel: 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(width, height);
+ let _ = rotate180_in(image, &mut out);
+ out
+}
+
+/// Rotate an image 270 degrees clockwise.
+pub fn rotate270<I: GenericImageView>(
+ image: &I,
+) -> ImageBuffer<I::Pixel, Vec<<I::Pixel as Pixel>::Subpixel>>
+where
+ I::Pixel: 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(height, width);
+ let _ = rotate270_in(image, &mut out);
+ out
+}
+
+/// Rotate an image 90 degrees clockwise and put the result into the destination [`ImageBuffer`].
+pub fn rotate90_in<I, Container>(
+ image: &I,
+ destination: &mut ImageBuffer<I::Pixel, Container>,
+) -> crate::ImageResult<()>
+where
+ I: GenericImageView,
+ I::Pixel: 'static,
+ Container: std::ops::DerefMut<Target = [<I::Pixel as Pixel>::Subpixel]>,
+{
+ let ((w0, h0), (w1, h1)) = (image.dimensions(), destination.dimensions());
+ if w0 != h1 || h0 != w1 {
+ return Err(ImageError::Parameter(ParameterError::from_kind(
+ ParameterErrorKind::DimensionMismatch,
+ )));
+ }
+
+ for y in 0..h0 {
+ for x in 0..w0 {
+ let p = image.get_pixel(x, y);
+ destination.put_pixel(h0 - y - 1, x, p);
+ }
+ }
+ Ok(())
+}
+
+/// Rotate an image 180 degrees clockwise and put the result into the destination [`ImageBuffer`].
+pub fn rotate180_in<I, Container>(
+ image: &I,
+ destination: &mut ImageBuffer<I::Pixel, Container>,
+) -> crate::ImageResult<()>
+where
+ I: GenericImageView,
+ I::Pixel: 'static,
+ Container: std::ops::DerefMut<Target = [<I::Pixel as Pixel>::Subpixel]>,
+{
+ let ((w0, h0), (w1, h1)) = (image.dimensions(), destination.dimensions());
+ if w0 != w1 || h0 != h1 {
+ return Err(ImageError::Parameter(ParameterError::from_kind(
+ ParameterErrorKind::DimensionMismatch,
+ )));
+ }
+
+ for y in 0..h0 {
+ for x in 0..w0 {
+ let p = image.get_pixel(x, y);
+ destination.put_pixel(w0 - x - 1, h0 - y - 1, p);
+ }
+ }
+ Ok(())
+}
+
+/// Rotate an image 270 degrees clockwise and put the result into the destination [`ImageBuffer`].
+pub fn rotate270_in<I, Container>(
+ image: &I,
+ destination: &mut ImageBuffer<I::Pixel, Container>,
+) -> crate::ImageResult<()>
+where
+ I: GenericImageView,
+ I::Pixel: 'static,
+ Container: std::ops::DerefMut<Target = [<I::Pixel as Pixel>::Subpixel]>,
+{
+ let ((w0, h0), (w1, h1)) = (image.dimensions(), destination.dimensions());
+ if w0 != h1 || h0 != w1 {
+ return Err(ImageError::Parameter(ParameterError::from_kind(
+ ParameterErrorKind::DimensionMismatch,
+ )));
+ }
+
+ for y in 0..h0 {
+ for x in 0..w0 {
+ let p = image.get_pixel(x, y);
+ destination.put_pixel(y, w0 - x - 1, p);
+ }
+ }
+ Ok(())
+}
+
+/// Flip an image horizontally
+pub fn flip_horizontal<I: GenericImageView>(
+ image: &I,
+) -> ImageBuffer<I::Pixel, Vec<<I::Pixel as Pixel>::Subpixel>>
+where
+ I::Pixel: 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(width, height);
+ let _ = flip_horizontal_in(image, &mut out);
+ out
+}
+
+/// Flip an image vertically
+pub fn flip_vertical<I: GenericImageView>(
+ image: &I,
+) -> ImageBuffer<I::Pixel, Vec<<I::Pixel as Pixel>::Subpixel>>
+where
+ I::Pixel: 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(width, height);
+ let _ = flip_vertical_in(image, &mut out);
+ out
+}
+
+/// Flip an image horizontally and put the result into the destination [`ImageBuffer`].
+pub fn flip_horizontal_in<I, Container>(
+ image: &I,
+ destination: &mut ImageBuffer<I::Pixel, Container>,
+) -> crate::ImageResult<()>
+where
+ I: GenericImageView,
+ I::Pixel: 'static,
+ Container: std::ops::DerefMut<Target = [<I::Pixel as Pixel>::Subpixel]>,
+{
+ let ((w0, h0), (w1, h1)) = (image.dimensions(), destination.dimensions());
+ if w0 != w1 || h0 != h1 {
+ return Err(ImageError::Parameter(ParameterError::from_kind(
+ ParameterErrorKind::DimensionMismatch,
+ )));
+ }
+
+ for y in 0..h0 {
+ for x in 0..w0 {
+ let p = image.get_pixel(x, y);
+ destination.put_pixel(w0 - x - 1, y, p);
+ }
+ }
+ Ok(())
+}
+
+/// Flip an image vertically and put the result into the destination [`ImageBuffer`].
+pub fn flip_vertical_in<I, Container>(
+ image: &I,
+ destination: &mut ImageBuffer<I::Pixel, Container>,
+) -> crate::ImageResult<()>
+where
+ I: GenericImageView,
+ I::Pixel: 'static,
+ Container: std::ops::DerefMut<Target = [<I::Pixel as Pixel>::Subpixel]>,
+{
+ let ((w0, h0), (w1, h1)) = (image.dimensions(), destination.dimensions());
+ if w0 != w1 || h0 != h1 {
+ return Err(ImageError::Parameter(ParameterError::from_kind(
+ ParameterErrorKind::DimensionMismatch,
+ )));
+ }
+
+ for y in 0..h0 {
+ for x in 0..w0 {
+ let p = image.get_pixel(x, y);
+ destination.put_pixel(x, h0 - 1 - y, p);
+ }
+ }
+ Ok(())
+}
+
+/// Rotate an image 180 degrees clockwise in place.
+pub fn rotate180_in_place<I: GenericImage>(image: &mut I) {
+ let (width, height) = image.dimensions();
+
+ for y in 0..height / 2 {
+ for x in 0..width {
+ let p = image.get_pixel(x, y);
+
+ let x2 = width - x - 1;
+ let y2 = height - y - 1;
+
+ let p2 = image.get_pixel(x2, y2);
+ image.put_pixel(x, y, p2);
+ image.put_pixel(x2, y2, p);
+ }
+ }
+
+ if height % 2 != 0 {
+ let middle = height / 2;
+
+ for x in 0..width / 2 {
+ let p = image.get_pixel(x, middle);
+ let x2 = width - x - 1;
+
+ let p2 = image.get_pixel(x2, middle);
+ image.put_pixel(x, middle, p2);
+ image.put_pixel(x2, middle, p);
+ }
+ }
+}
+
+/// Flip an image horizontally in place.
+pub fn flip_horizontal_in_place<I: GenericImage>(image: &mut I) {
+ let (width, height) = image.dimensions();
+
+ for y in 0..height {
+ for x in 0..width / 2 {
+ let x2 = width - x - 1;
+ let p2 = image.get_pixel(x2, y);
+ let p = image.get_pixel(x, y);
+ image.put_pixel(x2, y, p);
+ image.put_pixel(x, y, p2);
+ }
+ }
+}
+
+/// Flip an image vertically in place.
+pub fn flip_vertical_in_place<I: GenericImage>(image: &mut I) {
+ let (width, height) = image.dimensions();
+
+ for y in 0..height / 2 {
+ for x in 0..width {
+ let y2 = height - y - 1;
+ let p2 = image.get_pixel(x, y2);
+ let p = image.get_pixel(x, y);
+ image.put_pixel(x, y2, p);
+ image.put_pixel(x, y, p2);
+ }
+ }
+}
+
+#[cfg(test)]
+mod test {
+ use super::{
+ flip_horizontal, flip_horizontal_in_place, flip_vertical, flip_vertical_in_place,
+ rotate180, rotate180_in_place, rotate270, rotate90,
+ };
+ use crate::image::GenericImage;
+ use crate::traits::Pixel;
+ use crate::{GrayImage, ImageBuffer};
+
+ macro_rules! assert_pixels_eq {
+ ($actual:expr, $expected:expr) => {{
+ let actual_dim = $actual.dimensions();
+ let expected_dim = $expected.dimensions();
+
+ if actual_dim != expected_dim {
+ panic!(
+ "dimensions do not match. \
+ actual: {:?}, expected: {:?}",
+ actual_dim, expected_dim
+ )
+ }
+
+ let diffs = pixel_diffs($actual, $expected);
+
+ if !diffs.is_empty() {
+ let mut err = "".to_string();
+
+ let diff_messages = diffs
+ .iter()
+ .take(5)
+ .map(|d| format!("\nactual: {:?}, expected {:?} ", d.0, d.1))
+ .collect::<Vec<_>>()
+ .join("");
+
+ err.push_str(&diff_messages);
+ panic!("pixels do not match. {:?}", err)
+ }
+ }};
+ }
+
+ #[test]
+ fn test_rotate90() {
+ let image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(2, 3, vec![10u8, 00u8, 11u8, 01u8, 12u8, 02u8]).unwrap();
+
+ assert_pixels_eq!(&rotate90(&image), &expected);
+ }
+
+ #[test]
+ fn test_rotate180() {
+ let image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![12u8, 11u8, 10u8, 02u8, 01u8, 00u8]).unwrap();
+
+ assert_pixels_eq!(&rotate180(&image), &expected);
+ }
+
+ #[test]
+ fn test_rotate270() {
+ let image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(2, 3, vec![02u8, 12u8, 01u8, 11u8, 00u8, 10u8]).unwrap();
+
+ assert_pixels_eq!(&rotate270(&image), &expected);
+ }
+
+ #[test]
+ fn test_rotate180_in_place() {
+ let mut image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![12u8, 11u8, 10u8, 02u8, 01u8, 00u8]).unwrap();
+
+ rotate180_in_place(&mut image);
+
+ assert_pixels_eq!(&image, &expected);
+ }
+
+ #[test]
+ fn test_flip_horizontal() {
+ let image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![02u8, 01u8, 00u8, 12u8, 11u8, 10u8]).unwrap();
+
+ assert_pixels_eq!(&flip_horizontal(&image), &expected);
+ }
+
+ #[test]
+ fn test_flip_vertical() {
+ let image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![10u8, 11u8, 12u8, 00u8, 01u8, 02u8]).unwrap();
+
+ assert_pixels_eq!(&flip_vertical(&image), &expected);
+ }
+
+ #[test]
+ fn test_flip_horizontal_in_place() {
+ let mut image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![02u8, 01u8, 00u8, 12u8, 11u8, 10u8]).unwrap();
+
+ flip_horizontal_in_place(&mut image);
+
+ assert_pixels_eq!(&image, &expected);
+ }
+
+ #[test]
+ fn test_flip_vertical_in_place() {
+ let mut image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![10u8, 11u8, 12u8, 00u8, 01u8, 02u8]).unwrap();
+
+ flip_vertical_in_place(&mut image);
+
+ assert_pixels_eq!(&image, &expected);
+ }
+
+ fn pixel_diffs<I, J, P>(left: &I, right: &J) -> Vec<((u32, u32, P), (u32, u32, P))>
+ where
+ I: GenericImage<Pixel = P>,
+ J: GenericImage<Pixel = P>,
+ P: Pixel + Eq,
+ {
+ left.pixels()
+ .zip(right.pixels())
+ .filter(|&(p, q)| p != q)
+ .collect::<Vec<_>>()
+ }
+}
diff --git a/vendor/image/src/imageops/colorops.rs b/vendor/image/src/imageops/colorops.rs
new file mode 100644
index 0000000..085e5f4
--- /dev/null
+++ b/vendor/image/src/imageops/colorops.rs
@@ -0,0 +1,646 @@
+//! Functions for altering and converting the color of pixelbufs
+
+use num_traits::NumCast;
+use std::f64::consts::PI;
+
+use crate::color::{FromColor, IntoColor, Luma, LumaA, Rgba};
+use crate::image::{GenericImage, GenericImageView};
+use crate::traits::{Pixel, Primitive};
+use crate::utils::clamp;
+use crate::ImageBuffer;
+
+type Subpixel<I> = <<I as GenericImageView>::Pixel as Pixel>::Subpixel;
+
+/// Convert the supplied image to grayscale. Alpha channel is discarded.
+pub fn grayscale<I: GenericImageView>(
+ image: &I,
+) -> ImageBuffer<Luma<Subpixel<I>>, Vec<Subpixel<I>>> {
+ grayscale_with_type(image)
+}
+
+/// Convert the supplied image to grayscale. Alpha channel is preserved.
+pub fn grayscale_alpha<I: GenericImageView>(
+ image: &I,
+) -> ImageBuffer<LumaA<Subpixel<I>>, Vec<Subpixel<I>>> {
+ grayscale_with_type_alpha(image)
+}
+
+/// Convert the supplied image to a grayscale image with the specified pixel type. Alpha channel is discarded.
+pub fn grayscale_with_type<NewPixel, I: GenericImageView>(
+ image: &I,
+) -> ImageBuffer<NewPixel, Vec<NewPixel::Subpixel>>
+where
+ NewPixel: Pixel + FromColor<Luma<Subpixel<I>>>,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(width, height);
+
+ for (x, y, pixel) in image.pixels() {
+ let grayscale = pixel.to_luma();
+ let new_pixel = grayscale.into_color(); // no-op for luma->luma
+
+ out.put_pixel(x, y, new_pixel);
+ }
+
+ out
+}
+
+/// Convert the supplied image to a grayscale image with the specified pixel type. Alpha channel is preserved.
+pub fn grayscale_with_type_alpha<NewPixel, I: GenericImageView>(
+ image: &I,
+) -> ImageBuffer<NewPixel, Vec<NewPixel::Subpixel>>
+where
+ NewPixel: Pixel + FromColor<LumaA<Subpixel<I>>>,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(width, height);
+
+ for (x, y, pixel) in image.pixels() {
+ let grayscale = pixel.to_luma_alpha();
+ let new_pixel = grayscale.into_color(); // no-op for luma->luma
+
+ out.put_pixel(x, y, new_pixel);
+ }
+
+ out
+}
+
+/// Invert each pixel within the supplied image.
+/// This function operates in place.
+pub fn invert<I: GenericImage>(image: &mut I) {
+ // TODO find a way to use pixels?
+ let (width, height) = image.dimensions();
+
+ for y in 0..height {
+ for x in 0..width {
+ let mut p = image.get_pixel(x, y);
+ p.invert();
+
+ image.put_pixel(x, y, p);
+ }
+ }
+}
+
+/// Adjust the contrast of the supplied image.
+/// ```contrast``` is the amount to adjust the contrast by.
+/// Negative values decrease the contrast and positive values increase the contrast.
+///
+/// *[See also `contrast_in_place`.][contrast_in_place]*
+pub fn contrast<I, P, S>(image: &I, contrast: f32) -> ImageBuffer<P, Vec<S>>
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S> + 'static,
+ S: Primitive + 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(width, height);
+
+ let max = S::DEFAULT_MAX_VALUE;
+ let max: f32 = NumCast::from(max).unwrap();
+
+ let percent = ((100.0 + contrast) / 100.0).powi(2);
+
+ for (x, y, pixel) in image.pixels() {
+ let f = pixel.map(|b| {
+ let c: f32 = NumCast::from(b).unwrap();
+
+ let d = ((c / max - 0.5) * percent + 0.5) * max;
+ let e = clamp(d, 0.0, max);
+
+ NumCast::from(e).unwrap()
+ });
+ out.put_pixel(x, y, f);
+ }
+
+ out
+}
+
+/// Adjust the contrast of the supplied image in place.
+/// ```contrast``` is the amount to adjust the contrast by.
+/// Negative values decrease the contrast and positive values increase the contrast.
+///
+/// *[See also `contrast`.][contrast]*
+pub fn contrast_in_place<I>(image: &mut I, contrast: f32)
+where
+ I: GenericImage,
+{
+ let (width, height) = image.dimensions();
+
+ let max = <I::Pixel as Pixel>::Subpixel::DEFAULT_MAX_VALUE;
+ let max: f32 = NumCast::from(max).unwrap();
+
+ let percent = ((100.0 + contrast) / 100.0).powi(2);
+
+ // TODO find a way to use pixels?
+ for y in 0..height {
+ for x in 0..width {
+ let f = image.get_pixel(x, y).map(|b| {
+ let c: f32 = NumCast::from(b).unwrap();
+
+ let d = ((c / max - 0.5) * percent + 0.5) * max;
+ let e = clamp(d, 0.0, max);
+
+ NumCast::from(e).unwrap()
+ });
+
+ image.put_pixel(x, y, f);
+ }
+ }
+}
+
+/// Brighten the supplied image.
+/// ```value``` is the amount to brighten each pixel by.
+/// Negative values decrease the brightness and positive values increase it.
+///
+/// *[See also `brighten_in_place`.][brighten_in_place]*
+pub fn brighten<I, P, S>(image: &I, value: i32) -> ImageBuffer<P, Vec<S>>
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S> + 'static,
+ S: Primitive + 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(width, height);
+
+ let max = S::DEFAULT_MAX_VALUE;
+ let max: i32 = NumCast::from(max).unwrap();
+
+ for (x, y, pixel) in image.pixels() {
+ let e = pixel.map_with_alpha(
+ |b| {
+ let c: i32 = NumCast::from(b).unwrap();
+ let d = clamp(c + value, 0, max);
+
+ NumCast::from(d).unwrap()
+ },
+ |alpha| alpha,
+ );
+ out.put_pixel(x, y, e);
+ }
+
+ out
+}
+
+/// Brighten the supplied image in place.
+/// ```value``` is the amount to brighten each pixel by.
+/// Negative values decrease the brightness and positive values increase it.
+///
+/// *[See also `brighten`.][brighten]*
+pub fn brighten_in_place<I>(image: &mut I, value: i32)
+where
+ I: GenericImage,
+{
+ let (width, height) = image.dimensions();
+
+ let max = <I::Pixel as Pixel>::Subpixel::DEFAULT_MAX_VALUE;
+ let max: i32 = NumCast::from(max).unwrap(); // TODO what does this do for f32? clamp at 1??
+
+ // TODO find a way to use pixels?
+ for y in 0..height {
+ for x in 0..width {
+ let e = image.get_pixel(x, y).map_with_alpha(
+ |b| {
+ let c: i32 = NumCast::from(b).unwrap();
+ let d = clamp(c + value, 0, max);
+
+ NumCast::from(d).unwrap()
+ },
+ |alpha| alpha,
+ );
+
+ image.put_pixel(x, y, e);
+ }
+ }
+}
+
+/// Hue rotate the supplied image.
+/// `value` is the degrees to rotate each pixel by.
+/// 0 and 360 do nothing, the rest rotates by the given degree value.
+/// just like the css webkit filter hue-rotate(180)
+///
+/// *[See also `huerotate_in_place`.][huerotate_in_place]*
+pub fn huerotate<I, P, S>(image: &I, value: i32) -> ImageBuffer<P, Vec<S>>
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S> + 'static,
+ S: Primitive + 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(width, height);
+
+ let angle: f64 = NumCast::from(value).unwrap();
+
+ let cosv = (angle * PI / 180.0).cos();
+ let sinv = (angle * PI / 180.0).sin();
+ let matrix: [f64; 9] = [
+ // Reds
+ 0.213 + cosv * 0.787 - sinv * 0.213,
+ 0.715 - cosv * 0.715 - sinv * 0.715,
+ 0.072 - cosv * 0.072 + sinv * 0.928,
+ // Greens
+ 0.213 - cosv * 0.213 + sinv * 0.143,
+ 0.715 + cosv * 0.285 + sinv * 0.140,
+ 0.072 - cosv * 0.072 - sinv * 0.283,
+ // Blues
+ 0.213 - cosv * 0.213 - sinv * 0.787,
+ 0.715 - cosv * 0.715 + sinv * 0.715,
+ 0.072 + cosv * 0.928 + sinv * 0.072,
+ ];
+ for (x, y, pixel) in out.enumerate_pixels_mut() {
+ let p = image.get_pixel(x, y);
+
+ #[allow(deprecated)]
+ let (k1, k2, k3, k4) = p.channels4();
+ let vec: (f64, f64, f64, f64) = (
+ NumCast::from(k1).unwrap(),
+ NumCast::from(k2).unwrap(),
+ NumCast::from(k3).unwrap(),
+ NumCast::from(k4).unwrap(),
+ );
+
+ let r = vec.0;
+ let g = vec.1;
+ let b = vec.2;
+
+ let new_r = matrix[0] * r + matrix[1] * g + matrix[2] * b;
+ let new_g = matrix[3] * r + matrix[4] * g + matrix[5] * b;
+ let new_b = matrix[6] * r + matrix[7] * g + matrix[8] * b;
+ let max = 255f64;
+
+ #[allow(deprecated)]
+ let outpixel = Pixel::from_channels(
+ NumCast::from(clamp(new_r, 0.0, max)).unwrap(),
+ NumCast::from(clamp(new_g, 0.0, max)).unwrap(),
+ NumCast::from(clamp(new_b, 0.0, max)).unwrap(),
+ NumCast::from(clamp(vec.3, 0.0, max)).unwrap(),
+ );
+ *pixel = outpixel;
+ }
+ out
+}
+
+/// Hue rotate the supplied image in place.
+/// `value` is the degrees to rotate each pixel by.
+/// 0 and 360 do nothing, the rest rotates by the given degree value.
+/// just like the css webkit filter hue-rotate(180)
+///
+/// *[See also `huerotate`.][huerotate]*
+pub fn huerotate_in_place<I>(image: &mut I, value: i32)
+where
+ I: GenericImage,
+{
+ let (width, height) = image.dimensions();
+
+ let angle: f64 = NumCast::from(value).unwrap();
+
+ let cosv = (angle * PI / 180.0).cos();
+ let sinv = (angle * PI / 180.0).sin();
+ let matrix: [f64; 9] = [
+ // Reds
+ 0.213 + cosv * 0.787 - sinv * 0.213,
+ 0.715 - cosv * 0.715 - sinv * 0.715,
+ 0.072 - cosv * 0.072 + sinv * 0.928,
+ // Greens
+ 0.213 - cosv * 0.213 + sinv * 0.143,
+ 0.715 + cosv * 0.285 + sinv * 0.140,
+ 0.072 - cosv * 0.072 - sinv * 0.283,
+ // Blues
+ 0.213 - cosv * 0.213 - sinv * 0.787,
+ 0.715 - cosv * 0.715 + sinv * 0.715,
+ 0.072 + cosv * 0.928 + sinv * 0.072,
+ ];
+
+ // TODO find a way to use pixels?
+ for y in 0..height {
+ for x in 0..width {
+ let pixel = image.get_pixel(x, y);
+
+ #[allow(deprecated)]
+ let (k1, k2, k3, k4) = pixel.channels4();
+
+ let vec: (f64, f64, f64, f64) = (
+ NumCast::from(k1).unwrap(),
+ NumCast::from(k2).unwrap(),
+ NumCast::from(k3).unwrap(),
+ NumCast::from(k4).unwrap(),
+ );
+
+ let r = vec.0;
+ let g = vec.1;
+ let b = vec.2;
+
+ let new_r = matrix[0] * r + matrix[1] * g + matrix[2] * b;
+ let new_g = matrix[3] * r + matrix[4] * g + matrix[5] * b;
+ let new_b = matrix[6] * r + matrix[7] * g + matrix[8] * b;
+ let max = 255f64;
+
+ #[allow(deprecated)]
+ let outpixel = Pixel::from_channels(
+ NumCast::from(clamp(new_r, 0.0, max)).unwrap(),
+ NumCast::from(clamp(new_g, 0.0, max)).unwrap(),
+ NumCast::from(clamp(new_b, 0.0, max)).unwrap(),
+ NumCast::from(clamp(vec.3, 0.0, max)).unwrap(),
+ );
+
+ image.put_pixel(x, y, outpixel);
+ }
+ }
+}
+
+/// A color map
+pub trait ColorMap {
+ /// The color type on which the map operates on
+ type Color;
+ /// Returns the index of the closest match of `color`
+ /// in the color map.
+ fn index_of(&self, color: &Self::Color) -> usize;
+ /// Looks up color by index in the color map. If `idx` is out of range for the color map, or
+ /// ColorMap doesn't implement `lookup` `None` is returned.
+ fn lookup(&self, index: usize) -> Option<Self::Color> {
+ let _ = index;
+ None
+ }
+ /// Determine if this implementation of ColorMap overrides the default `lookup`.
+ fn has_lookup(&self) -> bool {
+ false
+ }
+ /// Maps `color` to the closest color in the color map.
+ fn map_color(&self, color: &mut Self::Color);
+}
+
+/// A bi-level color map
+///
+/// # Examples
+/// ```
+/// use image::imageops::colorops::{index_colors, BiLevel, ColorMap};
+/// use image::{ImageBuffer, Luma};
+///
+/// let (w, h) = (16, 16);
+/// // Create an image with a smooth horizontal gradient from black (0) to white (255).
+/// let gray = ImageBuffer::from_fn(w, h, |x, y| -> Luma<u8> { [(255 * x / w) as u8].into() });
+/// // Mapping the gray image through the `BiLevel` filter should map gray pixels less than half
+/// // intensity (127) to black (0), and anything greater to white (255).
+/// let cmap = BiLevel;
+/// let palletized = index_colors(&gray, &cmap);
+/// let mapped = ImageBuffer::from_fn(w, h, |x, y| {
+/// let p = palletized.get_pixel(x, y);
+/// cmap.lookup(p.0[0] as usize)
+/// .expect("indexed color out-of-range")
+/// });
+/// // Create an black and white image of expected output.
+/// let bw = ImageBuffer::from_fn(w, h, |x, y| -> Luma<u8> {
+/// if x <= (w / 2) {
+/// [0].into()
+/// } else {
+/// [255].into()
+/// }
+/// });
+/// assert_eq!(mapped, bw);
+/// ```
+#[derive(Clone, Copy)]
+pub struct BiLevel;
+
+impl ColorMap for BiLevel {
+ type Color = Luma<u8>;
+
+ #[inline(always)]
+ fn index_of(&self, color: &Luma<u8>) -> usize {
+ let luma = color.0;
+ if luma[0] > 127 {
+ 1
+ } else {
+ 0
+ }
+ }
+
+ #[inline(always)]
+ fn lookup(&self, idx: usize) -> Option<Self::Color> {
+ match idx {
+ 0 => Some([0].into()),
+ 1 => Some([255].into()),
+ _ => None,
+ }
+ }
+
+ /// Indicate NeuQuant implements `lookup`.
+ fn has_lookup(&self) -> bool {
+ true
+ }
+
+ #[inline(always)]
+ fn map_color(&self, color: &mut Luma<u8>) {
+ let new_color = 0xFF * self.index_of(color) as u8;
+ let luma = &mut color.0;
+ luma[0] = new_color;
+ }
+}
+
+impl ColorMap for color_quant::NeuQuant {
+ type Color = Rgba<u8>;
+
+ #[inline(always)]
+ fn index_of(&self, color: &Rgba<u8>) -> usize {
+ self.index_of(color.channels())
+ }
+
+ #[inline(always)]
+ fn lookup(&self, idx: usize) -> Option<Self::Color> {
+ self.lookup(idx).map(|p| p.into())
+ }
+
+ /// Indicate NeuQuant implements `lookup`.
+ fn has_lookup(&self) -> bool {
+ true
+ }
+
+ #[inline(always)]
+ fn map_color(&self, color: &mut Rgba<u8>) {
+ self.map_pixel(color.channels_mut())
+ }
+}
+
+/// Floyd-Steinberg error diffusion
+fn diffuse_err<P: Pixel<Subpixel = u8>>(pixel: &mut P, error: [i16; 3], factor: i16) {
+ for (e, c) in error.iter().zip(pixel.channels_mut().iter_mut()) {
+ *c = match <i16 as From<_>>::from(*c) + e * factor / 16 {
+ val if val < 0 => 0,
+ val if val > 0xFF => 0xFF,
+ val => val as u8,
+ }
+ }
+}
+
+macro_rules! do_dithering(
+ ($map:expr, $image:expr, $err:expr, $x:expr, $y:expr) => (
+ {
+ let old_pixel = $image[($x, $y)];
+ let new_pixel = $image.get_pixel_mut($x, $y);
+ $map.map_color(new_pixel);
+ for ((e, &old), &new) in $err.iter_mut()
+ .zip(old_pixel.channels().iter())
+ .zip(new_pixel.channels().iter())
+ {
+ *e = <i16 as From<_>>::from(old) - <i16 as From<_>>::from(new)
+ }
+ }
+ )
+);
+
+/// Reduces the colors of the image using the supplied `color_map` while applying
+/// Floyd-Steinberg dithering to improve the visual conception
+pub fn dither<Pix, Map>(image: &mut ImageBuffer<Pix, Vec<u8>>, color_map: &Map)
+where
+ Map: ColorMap<Color = Pix> + ?Sized,
+ Pix: Pixel<Subpixel = u8> + 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut err: [i16; 3] = [0; 3];
+ for y in 0..height - 1 {
+ let x = 0;
+ do_dithering!(color_map, image, err, x, y);
+ diffuse_err(image.get_pixel_mut(x + 1, y), err, 7);
+ diffuse_err(image.get_pixel_mut(x, y + 1), err, 5);
+ diffuse_err(image.get_pixel_mut(x + 1, y + 1), err, 1);
+ for x in 1..width - 1 {
+ do_dithering!(color_map, image, err, x, y);
+ diffuse_err(image.get_pixel_mut(x + 1, y), err, 7);
+ diffuse_err(image.get_pixel_mut(x - 1, y + 1), err, 3);
+ diffuse_err(image.get_pixel_mut(x, y + 1), err, 5);
+ diffuse_err(image.get_pixel_mut(x + 1, y + 1), err, 1);
+ }
+ let x = width - 1;
+ do_dithering!(color_map, image, err, x, y);
+ diffuse_err(image.get_pixel_mut(x - 1, y + 1), err, 3);
+ diffuse_err(image.get_pixel_mut(x, y + 1), err, 5);
+ }
+ let y = height - 1;
+ let x = 0;
+ do_dithering!(color_map, image, err, x, y);
+ diffuse_err(image.get_pixel_mut(x + 1, y), err, 7);
+ for x in 1..width - 1 {
+ do_dithering!(color_map, image, err, x, y);
+ diffuse_err(image.get_pixel_mut(x + 1, y), err, 7);
+ }
+ let x = width - 1;
+ do_dithering!(color_map, image, err, x, y);
+}
+
+/// Reduces the colors using the supplied `color_map` and returns an image of the indices
+pub fn index_colors<Pix, Map>(
+ image: &ImageBuffer<Pix, Vec<u8>>,
+ color_map: &Map,
+) -> ImageBuffer<Luma<u8>, Vec<u8>>
+where
+ Map: ColorMap<Color = Pix> + ?Sized,
+ Pix: Pixel<Subpixel = u8> + 'static,
+{
+ let mut indices = ImageBuffer::new(image.width(), image.height());
+ for (pixel, idx) in image.pixels().zip(indices.pixels_mut()) {
+ *idx = Luma([color_map.index_of(pixel) as u8])
+ }
+ indices
+}
+
+#[cfg(test)]
+mod test {
+
+ use super::*;
+ use crate::{GrayImage, ImageBuffer};
+
+ macro_rules! assert_pixels_eq {
+ ($actual:expr, $expected:expr) => {{
+ let actual_dim = $actual.dimensions();
+ let expected_dim = $expected.dimensions();
+
+ if actual_dim != expected_dim {
+ panic!(
+ "dimensions do not match. \
+ actual: {:?}, expected: {:?}",
+ actual_dim, expected_dim
+ )
+ }
+
+ let diffs = pixel_diffs($actual, $expected);
+
+ if !diffs.is_empty() {
+ let mut err = "".to_string();
+
+ let diff_messages = diffs
+ .iter()
+ .take(5)
+ .map(|d| format!("\nactual: {:?}, expected {:?} ", d.0, d.1))
+ .collect::<Vec<_>>()
+ .join("");
+
+ err.push_str(&diff_messages);
+ panic!("pixels do not match. {:?}", err)
+ }
+ }};
+ }
+
+ #[test]
+ fn test_dither() {
+ let mut image = ImageBuffer::from_raw(2, 2, vec![127, 127, 127, 127]).unwrap();
+ let cmap = BiLevel;
+ dither(&mut image, &cmap);
+ assert_eq!(&*image, &[0, 0xFF, 0xFF, 0]);
+ assert_eq!(index_colors(&image, &cmap).into_raw(), vec![0, 1, 1, 0])
+ }
+
+ #[test]
+ fn test_grayscale() {
+ let mut image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ assert_pixels_eq!(&grayscale(&mut image), &expected);
+ }
+
+ #[test]
+ fn test_invert() {
+ let mut image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![255u8, 254u8, 253u8, 245u8, 244u8, 243u8]).unwrap();
+
+ invert(&mut image);
+ assert_pixels_eq!(&image, &expected);
+ }
+ #[test]
+ fn test_brighten() {
+ let image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![10u8, 11u8, 12u8, 20u8, 21u8, 22u8]).unwrap();
+
+ assert_pixels_eq!(&brighten(&image, 10), &expected);
+ }
+
+ #[test]
+ fn test_brighten_place() {
+ let mut image: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![00u8, 01u8, 02u8, 10u8, 11u8, 12u8]).unwrap();
+
+ let expected: GrayImage =
+ ImageBuffer::from_raw(3, 2, vec![10u8, 11u8, 12u8, 20u8, 21u8, 22u8]).unwrap();
+
+ brighten_in_place(&mut image, 10);
+ assert_pixels_eq!(&image, &expected);
+ }
+
+ fn pixel_diffs<I, J, P>(left: &I, right: &J) -> Vec<((u32, u32, P), (u32, u32, P))>
+ where
+ I: GenericImage<Pixel = P>,
+ J: GenericImage<Pixel = P>,
+ P: Pixel + Eq,
+ {
+ left.pixels()
+ .zip(right.pixels())
+ .filter(|&(p, q)| p != q)
+ .collect::<Vec<_>>()
+ }
+}
diff --git a/vendor/image/src/imageops/mod.rs b/vendor/image/src/imageops/mod.rs
new file mode 100644
index 0000000..fdd2bf3
--- /dev/null
+++ b/vendor/image/src/imageops/mod.rs
@@ -0,0 +1,485 @@
+//! Image Processing Functions
+use std::cmp;
+
+use crate::image::{GenericImage, GenericImageView, SubImage};
+use crate::traits::{Lerp, Pixel, Primitive};
+
+pub use self::sample::FilterType;
+
+pub use self::sample::FilterType::{CatmullRom, Gaussian, Lanczos3, Nearest, Triangle};
+
+/// Affine transformations
+pub use self::affine::{
+ flip_horizontal, flip_horizontal_in, flip_horizontal_in_place, flip_vertical, flip_vertical_in,
+ flip_vertical_in_place, rotate180, rotate180_in, rotate180_in_place, rotate270, rotate270_in,
+ rotate90, rotate90_in,
+};
+
+/// Image sampling
+pub use self::sample::{
+ blur, filter3x3, interpolate_bilinear, interpolate_nearest, resize, sample_bilinear,
+ sample_nearest, thumbnail, unsharpen,
+};
+
+/// Color operations
+pub use self::colorops::{
+ brighten, contrast, dither, grayscale, grayscale_alpha, grayscale_with_type,
+ grayscale_with_type_alpha, huerotate, index_colors, invert, BiLevel, ColorMap,
+};
+
+mod affine;
+// Public only because of Rust bug:
+// https://github.com/rust-lang/rust/issues/18241
+pub mod colorops;
+mod sample;
+
+/// Return a mutable view into an image
+/// The coordinates set the position of the top left corner of the crop.
+pub fn crop<I: GenericImageView>(
+ image: &mut I,
+ x: u32,
+ y: u32,
+ width: u32,
+ height: u32,
+) -> SubImage<&mut I> {
+ let (x, y, width, height) = crop_dimms(image, x, y, width, height);
+ SubImage::new(image, x, y, width, height)
+}
+
+/// Return an immutable view into an image
+/// The coordinates set the position of the top left corner of the crop.
+pub fn crop_imm<I: GenericImageView>(
+ image: &I,
+ x: u32,
+ y: u32,
+ width: u32,
+ height: u32,
+) -> SubImage<&I> {
+ let (x, y, width, height) = crop_dimms(image, x, y, width, height);
+ SubImage::new(image, x, y, width, height)
+}
+
+fn crop_dimms<I: GenericImageView>(
+ image: &I,
+ x: u32,
+ y: u32,
+ width: u32,
+ height: u32,
+) -> (u32, u32, u32, u32) {
+ let (iwidth, iheight) = image.dimensions();
+
+ let x = cmp::min(x, iwidth);
+ let y = cmp::min(y, iheight);
+
+ let height = cmp::min(height, iheight - y);
+ let width = cmp::min(width, iwidth - x);
+
+ (x, y, width, height)
+}
+
+/// Calculate the region that can be copied from top to bottom.
+///
+/// Given image size of bottom and top image, and a point at which we want to place the top image
+/// onto the bottom image, how large can we be? Have to wary of the following issues:
+/// * Top might be larger than bottom
+/// * Overflows in the computation
+/// * Coordinates could be completely out of bounds
+///
+/// The main idea is to make use of inequalities provided by the nature of `saturating_add` and
+/// `saturating_sub`. These intrinsically validate that all resulting coordinates will be in bounds
+/// for both images.
+///
+/// We want that all these coordinate accesses are safe:
+/// 1. `bottom.get_pixel(x + [0..x_range), y + [0..y_range))`
+/// 2. `top.get_pixel([0..x_range), [0..y_range))`
+///
+/// Proof that the function provides the necessary bounds for width. Note that all unaugmented math
+/// operations are to be read in standard arithmetic, not integer arithmetic. Since no direct
+/// integer arithmetic occurs in the implementation, this is unambiguous.
+///
+/// ```text
+/// Three short notes/lemmata:
+/// - Iff `(a - b) <= 0` then `a.saturating_sub(b) = 0`
+/// - Iff `(a - b) >= 0` then `a.saturating_sub(b) = a - b`
+/// - If `a <= c` then `a.saturating_sub(b) <= c.saturating_sub(b)`
+///
+/// 1.1 We show that if `bottom_width <= x`, then `x_range = 0` therefore `x + [0..x_range)` is empty.
+///
+/// x_range
+/// = (top_width.saturating_add(x).min(bottom_width)).saturating_sub(x)
+/// <= bottom_width.saturating_sub(x)
+///
+/// bottom_width <= x
+/// <==> bottom_width - x <= 0
+/// <==> bottom_width.saturating_sub(x) = 0
+/// ==> x_range <= 0
+/// ==> x_range = 0
+///
+/// 1.2 If `x < bottom_width` then `x + x_range < bottom_width`
+///
+/// x + x_range
+/// <= x + bottom_width.saturating_sub(x)
+/// = x + (bottom_width - x)
+/// = bottom_width
+///
+/// 2. We show that `x_range <= top_width`
+///
+/// x_range
+/// = (top_width.saturating_add(x).min(bottom_width)).saturating_sub(x)
+/// <= top_width.saturating_add(x).saturating_sub(x)
+/// <= (top_wdith + x).saturating_sub(x)
+/// = top_width (due to `top_width >= 0` and `x >= 0`)
+/// ```
+///
+/// Proof is the same for height.
+pub fn overlay_bounds(
+ (bottom_width, bottom_height): (u32, u32),
+ (top_width, top_height): (u32, u32),
+ x: u32,
+ y: u32,
+) -> (u32, u32) {
+ let x_range = top_width
+ .saturating_add(x) // Calculate max coordinate
+ .min(bottom_width) // Restrict to lower width
+ .saturating_sub(x); // Determinate length from start `x`
+ let y_range = top_height
+ .saturating_add(y)
+ .min(bottom_height)
+ .saturating_sub(y);
+ (x_range, y_range)
+}
+
+/// Calculate the region that can be copied from top to bottom.
+///
+/// Given image size of bottom and top image, and a point at which we want to place the top image
+/// onto the bottom image, how large can we be? Have to wary of the following issues:
+/// * Top might be larger than bottom
+/// * Overflows in the computation
+/// * Coordinates could be completely out of bounds
+///
+/// The returned value is of the form:
+///
+/// `(origin_bottom_x, origin_bottom_y, origin_top_x, origin_top_y, x_range, y_range)`
+///
+/// The main idea is to do computations on i64's and then clamp to image dimensions.
+/// In particular, we want to ensure that all these coordinate accesses are safe:
+/// 1. `bottom.get_pixel(origin_bottom_x + [0..x_range), origin_bottom_y + [0..y_range))`
+/// 2. `top.get_pixel(origin_top_y + [0..x_range), origin_top_y + [0..y_range))`
+///
+fn overlay_bounds_ext(
+ (bottom_width, bottom_height): (u32, u32),
+ (top_width, top_height): (u32, u32),
+ x: i64,
+ y: i64,
+) -> (u32, u32, u32, u32, u32, u32) {
+ // Return a predictable value if the two images don't overlap at all.
+ if x > i64::from(bottom_width)
+ || y > i64::from(bottom_height)
+ || x.saturating_add(i64::from(top_width)) <= 0
+ || y.saturating_add(i64::from(top_height)) <= 0
+ {
+ return (0, 0, 0, 0, 0, 0);
+ }
+
+ // Find the maximum x and y coordinates in terms of the bottom image.
+ let max_x = x.saturating_add(i64::from(top_width));
+ let max_y = y.saturating_add(i64::from(top_height));
+
+ // Clip the origin and maximum coordinates to the bounds of the bottom image.
+ // Casting to a u32 is safe because both 0 and `bottom_{width,height}` fit
+ // into 32-bits.
+ let max_inbounds_x = max_x.clamp(0, i64::from(bottom_width)) as u32;
+ let max_inbounds_y = max_y.clamp(0, i64::from(bottom_height)) as u32;
+ let origin_bottom_x = x.clamp(0, i64::from(bottom_width)) as u32;
+ let origin_bottom_y = y.clamp(0, i64::from(bottom_height)) as u32;
+
+ // The range is the difference between the maximum inbounds coordinates and
+ // the clipped origin. Unchecked subtraction is safe here because both are
+ // always positive and `max_inbounds_{x,y}` >= `origin_{x,y}` due to
+ // `top_{width,height}` being >= 0.
+ let x_range = max_inbounds_x - origin_bottom_x;
+ let y_range = max_inbounds_y - origin_bottom_y;
+
+ // If x (or y) is negative, then the origin of the top image is shifted by -x (or -y).
+ let origin_top_x = x.saturating_mul(-1).clamp(0, i64::from(top_width)) as u32;
+ let origin_top_y = y.saturating_mul(-1).clamp(0, i64::from(top_height)) as u32;
+
+ (
+ origin_bottom_x,
+ origin_bottom_y,
+ origin_top_x,
+ origin_top_y,
+ x_range,
+ y_range,
+ )
+}
+
+/// Overlay an image at a given coordinate (x, y)
+pub fn overlay<I, J>(bottom: &mut I, top: &J, x: i64, y: i64)
+where
+ I: GenericImage,
+ J: GenericImageView<Pixel = I::Pixel>,
+{
+ let bottom_dims = bottom.dimensions();
+ let top_dims = top.dimensions();
+
+ // Crop our top image if we're going out of bounds
+ let (origin_bottom_x, origin_bottom_y, origin_top_x, origin_top_y, range_width, range_height) =
+ overlay_bounds_ext(bottom_dims, top_dims, x, y);
+
+ for y in 0..range_height {
+ for x in 0..range_width {
+ let p = top.get_pixel(origin_top_x + x, origin_top_y + y);
+ let mut bottom_pixel = bottom.get_pixel(origin_bottom_x + x, origin_bottom_y + y);
+ bottom_pixel.blend(&p);
+
+ bottom.put_pixel(origin_bottom_x + x, origin_bottom_y + y, bottom_pixel);
+ }
+ }
+}
+
+/// Tile an image by repeating it multiple times
+///
+/// # Examples
+/// ```no_run
+/// use image::{RgbaImage};
+///
+/// let mut img = RgbaImage::new(1920, 1080);
+/// let tile = image::open("tile.png").unwrap();
+///
+/// image::imageops::tile(&mut img, &tile);
+/// img.save("tiled_wallpaper.png").unwrap();
+/// ```
+pub fn tile<I, J>(bottom: &mut I, top: &J)
+where
+ I: GenericImage,
+ J: GenericImageView<Pixel = I::Pixel>,
+{
+ for x in (0..bottom.width()).step_by(top.width() as usize) {
+ for y in (0..bottom.height()).step_by(top.height() as usize) {
+ overlay(bottom, top, i64::from(x), i64::from(y));
+ }
+ }
+}
+
+/// Fill the image with a linear vertical gradient
+///
+/// This function assumes a linear color space.
+///
+/// # Examples
+/// ```no_run
+/// use image::{Rgba, RgbaImage, Pixel};
+///
+/// let mut img = RgbaImage::new(100, 100);
+/// let start = Rgba::from_slice(&[0, 128, 0, 0]);
+/// let end = Rgba::from_slice(&[255, 255, 255, 255]);
+///
+/// image::imageops::vertical_gradient(&mut img, start, end);
+/// img.save("vertical_gradient.png").unwrap();
+pub fn vertical_gradient<S, P, I>(img: &mut I, start: &P, stop: &P)
+where
+ I: GenericImage<Pixel = P>,
+ P: Pixel<Subpixel = S> + 'static,
+ S: Primitive + Lerp + 'static,
+{
+ for y in 0..img.height() {
+ let pixel = start.map2(stop, |a, b| {
+ let y = <S::Ratio as num_traits::NumCast>::from(y).unwrap();
+ let height = <S::Ratio as num_traits::NumCast>::from(img.height() - 1).unwrap();
+ S::lerp(a, b, y / height)
+ });
+
+ for x in 0..img.width() {
+ img.put_pixel(x, y, pixel);
+ }
+ }
+}
+
+/// Fill the image with a linear horizontal gradient
+///
+/// This function assumes a linear color space.
+///
+/// # Examples
+/// ```no_run
+/// use image::{Rgba, RgbaImage, Pixel};
+///
+/// let mut img = RgbaImage::new(100, 100);
+/// let start = Rgba::from_slice(&[0, 128, 0, 0]);
+/// let end = Rgba::from_slice(&[255, 255, 255, 255]);
+///
+/// image::imageops::horizontal_gradient(&mut img, start, end);
+/// img.save("horizontal_gradient.png").unwrap();
+pub fn horizontal_gradient<S, P, I>(img: &mut I, start: &P, stop: &P)
+where
+ I: GenericImage<Pixel = P>,
+ P: Pixel<Subpixel = S> + 'static,
+ S: Primitive + Lerp + 'static,
+{
+ for x in 0..img.width() {
+ let pixel = start.map2(stop, |a, b| {
+ let x = <S::Ratio as num_traits::NumCast>::from(x).unwrap();
+ let width = <S::Ratio as num_traits::NumCast>::from(img.width() - 1).unwrap();
+ S::lerp(a, b, x / width)
+ });
+
+ for y in 0..img.height() {
+ img.put_pixel(x, y, pixel);
+ }
+ }
+}
+
+/// Replace the contents of an image at a given coordinate (x, y)
+pub fn replace<I, J>(bottom: &mut I, top: &J, x: i64, y: i64)
+where
+ I: GenericImage,
+ J: GenericImageView<Pixel = I::Pixel>,
+{
+ let bottom_dims = bottom.dimensions();
+ let top_dims = top.dimensions();
+
+ // Crop our top image if we're going out of bounds
+ let (origin_bottom_x, origin_bottom_y, origin_top_x, origin_top_y, range_width, range_height) =
+ overlay_bounds_ext(bottom_dims, top_dims, x, y);
+
+ for y in 0..range_height {
+ for x in 0..range_width {
+ let p = top.get_pixel(origin_top_x + x, origin_top_y + y);
+ bottom.put_pixel(origin_bottom_x + x, origin_bottom_y + y, p);
+ }
+ }
+}
+
+#[cfg(test)]
+mod tests {
+
+ use super::{overlay, overlay_bounds_ext};
+ use crate::color::Rgb;
+ use crate::ImageBuffer;
+ use crate::RgbaImage;
+
+ #[test]
+ fn test_overlay_bounds_ext() {
+ assert_eq!(
+ overlay_bounds_ext((10, 10), (10, 10), 0, 0),
+ (0, 0, 0, 0, 10, 10)
+ );
+ assert_eq!(
+ overlay_bounds_ext((10, 10), (10, 10), 1, 0),
+ (1, 0, 0, 0, 9, 10)
+ );
+ assert_eq!(
+ overlay_bounds_ext((10, 10), (10, 10), 0, 11),
+ (0, 0, 0, 0, 0, 0)
+ );
+ assert_eq!(
+ overlay_bounds_ext((10, 10), (10, 10), -1, 0),
+ (0, 0, 1, 0, 9, 10)
+ );
+ assert_eq!(
+ overlay_bounds_ext((10, 10), (10, 10), -10, 0),
+ (0, 0, 0, 0, 0, 0)
+ );
+ assert_eq!(
+ overlay_bounds_ext((10, 10), (10, 10), 1i64 << 50, 0),
+ (0, 0, 0, 0, 0, 0)
+ );
+ assert_eq!(
+ overlay_bounds_ext((10, 10), (10, 10), -(1i64 << 50), 0),
+ (0, 0, 0, 0, 0, 0)
+ );
+ assert_eq!(
+ overlay_bounds_ext((10, 10), (u32::MAX, 10), 10 - i64::from(u32::MAX), 0),
+ (0, 0, u32::MAX - 10, 0, 10, 10)
+ );
+ }
+
+ #[test]
+ /// Test that images written into other images works
+ fn test_image_in_image() {
+ let mut target = ImageBuffer::new(32, 32);
+ let source = ImageBuffer::from_pixel(16, 16, Rgb([255u8, 0, 0]));
+ overlay(&mut target, &source, 0, 0);
+ assert!(*target.get_pixel(0, 0) == Rgb([255u8, 0, 0]));
+ assert!(*target.get_pixel(15, 0) == Rgb([255u8, 0, 0]));
+ assert!(*target.get_pixel(16, 0) == Rgb([0u8, 0, 0]));
+ assert!(*target.get_pixel(0, 15) == Rgb([255u8, 0, 0]));
+ assert!(*target.get_pixel(0, 16) == Rgb([0u8, 0, 0]));
+ }
+
+ #[test]
+ /// Test that images written outside of a frame doesn't blow up
+ fn test_image_in_image_outside_of_bounds() {
+ let mut target = ImageBuffer::new(32, 32);
+ let source = ImageBuffer::from_pixel(32, 32, Rgb([255u8, 0, 0]));
+ overlay(&mut target, &source, 1, 1);
+ assert!(*target.get_pixel(0, 0) == Rgb([0, 0, 0]));
+ assert!(*target.get_pixel(1, 1) == Rgb([255u8, 0, 0]));
+ assert!(*target.get_pixel(31, 31) == Rgb([255u8, 0, 0]));
+ }
+
+ #[test]
+ /// Test that images written to coordinates out of the frame doesn't blow up
+ /// (issue came up in #848)
+ fn test_image_outside_image_no_wrap_around() {
+ let mut target = ImageBuffer::new(32, 32);
+ let source = ImageBuffer::from_pixel(32, 32, Rgb([255u8, 0, 0]));
+ overlay(&mut target, &source, 33, 33);
+ assert!(*target.get_pixel(0, 0) == Rgb([0, 0, 0]));
+ assert!(*target.get_pixel(1, 1) == Rgb([0, 0, 0]));
+ assert!(*target.get_pixel(31, 31) == Rgb([0, 0, 0]));
+ }
+
+ #[test]
+ /// Test that images written to coordinates with overflow works
+ fn test_image_coordinate_overflow() {
+ let mut target = ImageBuffer::new(16, 16);
+ let source = ImageBuffer::from_pixel(32, 32, Rgb([255u8, 0, 0]));
+ // Overflows to 'sane' coordinates but top is larger than bot.
+ overlay(
+ &mut target,
+ &source,
+ i64::from(u32::max_value() - 31),
+ i64::from(u32::max_value() - 31),
+ );
+ assert!(*target.get_pixel(0, 0) == Rgb([0, 0, 0]));
+ assert!(*target.get_pixel(1, 1) == Rgb([0, 0, 0]));
+ assert!(*target.get_pixel(15, 15) == Rgb([0, 0, 0]));
+ }
+
+ use super::{horizontal_gradient, vertical_gradient};
+
+ #[test]
+ /// Test that horizontal gradients are correctly generated
+ fn test_image_horizontal_gradient_limits() {
+ let mut img = ImageBuffer::new(100, 1);
+
+ let start = Rgb([0u8, 128, 0]);
+ let end = Rgb([255u8, 255, 255]);
+
+ horizontal_gradient(&mut img, &start, &end);
+
+ assert_eq!(img.get_pixel(0, 0), &start);
+ assert_eq!(img.get_pixel(img.width() - 1, 0), &end);
+ }
+
+ #[test]
+ /// Test that vertical gradients are correctly generated
+ fn test_image_vertical_gradient_limits() {
+ let mut img = ImageBuffer::new(1, 100);
+
+ let start = Rgb([0u8, 128, 0]);
+ let end = Rgb([255u8, 255, 255]);
+
+ vertical_gradient(&mut img, &start, &end);
+
+ assert_eq!(img.get_pixel(0, 0), &start);
+ assert_eq!(img.get_pixel(0, img.height() - 1), &end);
+ }
+
+ #[test]
+ /// Test blur doesn't panick when passed 0.0
+ fn test_blur_zero() {
+ let image = RgbaImage::new(50, 50);
+ let _ = super::blur(&image, 0.0);
+ }
+}
diff --git a/vendor/image/src/imageops/sample.rs b/vendor/image/src/imageops/sample.rs
new file mode 100644
index 0000000..a362f83
--- /dev/null
+++ b/vendor/image/src/imageops/sample.rs
@@ -0,0 +1,1228 @@
+//! Functions and filters for the sampling of pixels.
+
+// See http://cs.brown.edu/courses/cs123/lectures/08_Image_Processing_IV.pdf
+// for some of the theory behind image scaling and convolution
+
+use std::f32;
+
+use num_traits::{NumCast, ToPrimitive, Zero};
+
+use crate::image::{GenericImage, GenericImageView};
+use crate::traits::{Enlargeable, Pixel, Primitive};
+use crate::utils::clamp;
+use crate::{ImageBuffer, Rgba32FImage};
+
+/// Available Sampling Filters.
+///
+/// ## Examples
+///
+/// To test the different sampling filters on a real example, you can find two
+/// examples called
+/// [`scaledown`](https://github.com/image-rs/image/tree/master/examples/scaledown)
+/// and
+/// [`scaleup`](https://github.com/image-rs/image/tree/master/examples/scaleup)
+/// in the `examples` directory of the crate source code.
+///
+/// Here is a 3.58 MiB
+/// [test image](https://github.com/image-rs/image/blob/master/examples/scaledown/test.jpg)
+/// that has been scaled down to 300x225 px:
+///
+/// <!-- NOTE: To test new test images locally, replace the GitHub path with `../../../docs/` -->
+/// <div style="display: flex; flex-wrap: wrap; align-items: flex-start;">
+/// <div style="margin: 0 8px 8px 0;">
+/// <img src="https://raw.githubusercontent.com/image-rs/image/master/examples/scaledown/scaledown-test-near.png" title="Nearest"><br>
+/// Nearest Neighbor
+/// </div>
+/// <div style="margin: 0 8px 8px 0;">
+/// <img src="https://raw.githubusercontent.com/image-rs/image/master/examples/scaledown/scaledown-test-tri.png" title="Triangle"><br>
+/// Linear: Triangle
+/// </div>
+/// <div style="margin: 0 8px 8px 0;">
+/// <img src="https://raw.githubusercontent.com/image-rs/image/master/examples/scaledown/scaledown-test-cmr.png" title="CatmullRom"><br>
+/// Cubic: Catmull-Rom
+/// </div>
+/// <div style="margin: 0 8px 8px 0;">
+/// <img src="https://raw.githubusercontent.com/image-rs/image/master/examples/scaledown/scaledown-test-gauss.png" title="Gaussian"><br>
+/// Gaussian
+/// </div>
+/// <div style="margin: 0 8px 8px 0;">
+/// <img src="https://raw.githubusercontent.com/image-rs/image/master/examples/scaledown/scaledown-test-lcz2.png" title="Lanczos3"><br>
+/// Lanczos with window 3
+/// </div>
+/// </div>
+///
+/// ## Speed
+///
+/// Time required to create each of the examples above, tested on an Intel
+/// i7-4770 CPU with Rust 1.37 in release mode:
+///
+/// <table style="width: auto;">
+/// <tr>
+/// <th>Nearest</th>
+/// <td>31 ms</td>
+/// </tr>
+/// <tr>
+/// <th>Triangle</th>
+/// <td>414 ms</td>
+/// </tr>
+/// <tr>
+/// <th>CatmullRom</th>
+/// <td>817 ms</td>
+/// </tr>
+/// <tr>
+/// <th>Gaussian</th>
+/// <td>1180 ms</td>
+/// </tr>
+/// <tr>
+/// <th>Lanczos3</th>
+/// <td>1170 ms</td>
+/// </tr>
+/// </table>
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub enum FilterType {
+ /// Nearest Neighbor
+ Nearest,
+
+ /// Linear Filter
+ Triangle,
+
+ /// Cubic Filter
+ CatmullRom,
+
+ /// Gaussian Filter
+ Gaussian,
+
+ /// Lanczos with window 3
+ Lanczos3,
+}
+
+/// A Representation of a separable filter.
+pub(crate) struct Filter<'a> {
+ /// The filter's filter function.
+ pub(crate) kernel: Box<dyn Fn(f32) -> f32 + 'a>,
+
+ /// The window on which this filter operates.
+ pub(crate) support: f32,
+}
+
+struct FloatNearest(f32);
+
+// to_i64, to_u64, and to_f64 implicitly affect all other lower conversions.
+// Note that to_f64 by default calls to_i64 and thus needs to be overridden.
+impl ToPrimitive for FloatNearest {
+ // to_{i,u}64 is required, to_{i,u}{8,16} are useful.
+ // If a usecase for full 32 bits is found its trivial to add
+ fn to_i8(&self) -> Option<i8> {
+ self.0.round().to_i8()
+ }
+ fn to_i16(&self) -> Option<i16> {
+ self.0.round().to_i16()
+ }
+ fn to_i64(&self) -> Option<i64> {
+ self.0.round().to_i64()
+ }
+ fn to_u8(&self) -> Option<u8> {
+ self.0.round().to_u8()
+ }
+ fn to_u16(&self) -> Option<u16> {
+ self.0.round().to_u16()
+ }
+ fn to_u64(&self) -> Option<u64> {
+ self.0.round().to_u64()
+ }
+ fn to_f64(&self) -> Option<f64> {
+ self.0.to_f64()
+ }
+}
+
+// sinc function: the ideal sampling filter.
+fn sinc(t: f32) -> f32 {
+ let a = t * f32::consts::PI;
+
+ if t == 0.0 {
+ 1.0
+ } else {
+ a.sin() / a
+ }
+}
+
+// lanczos kernel function. A windowed sinc function.
+fn lanczos(x: f32, t: f32) -> f32 {
+ if x.abs() < t {
+ sinc(x) * sinc(x / t)
+ } else {
+ 0.0
+ }
+}
+
+// Calculate a splice based on the b and c parameters.
+// from authors Mitchell and Netravali.
+fn bc_cubic_spline(x: f32, b: f32, c: f32) -> f32 {
+ let a = x.abs();
+
+ let k = if a < 1.0 {
+ (12.0 - 9.0 * b - 6.0 * c) * a.powi(3)
+ + (-18.0 + 12.0 * b + 6.0 * c) * a.powi(2)
+ + (6.0 - 2.0 * b)
+ } else if a < 2.0 {
+ (-b - 6.0 * c) * a.powi(3)
+ + (6.0 * b + 30.0 * c) * a.powi(2)
+ + (-12.0 * b - 48.0 * c) * a
+ + (8.0 * b + 24.0 * c)
+ } else {
+ 0.0
+ };
+
+ k / 6.0
+}
+
+/// The Gaussian Function.
+/// ```r``` is the standard deviation.
+pub(crate) fn gaussian(x: f32, r: f32) -> f32 {
+ ((2.0 * f32::consts::PI).sqrt() * r).recip() * (-x.powi(2) / (2.0 * r.powi(2))).exp()
+}
+
+/// Calculate the lanczos kernel with a window of 3
+pub(crate) fn lanczos3_kernel(x: f32) -> f32 {
+ lanczos(x, 3.0)
+}
+
+/// Calculate the gaussian function with a
+/// standard deviation of 0.5
+pub(crate) fn gaussian_kernel(x: f32) -> f32 {
+ gaussian(x, 0.5)
+}
+
+/// Calculate the Catmull-Rom cubic spline.
+/// Also known as a form of `BiCubic` sampling in two dimensions.
+pub(crate) fn catmullrom_kernel(x: f32) -> f32 {
+ bc_cubic_spline(x, 0.0, 0.5)
+}
+
+/// Calculate the triangle function.
+/// Also known as `BiLinear` sampling in two dimensions.
+pub(crate) fn triangle_kernel(x: f32) -> f32 {
+ if x.abs() < 1.0 {
+ 1.0 - x.abs()
+ } else {
+ 0.0
+ }
+}
+
+/// Calculate the box kernel.
+/// Only pixels inside the box should be considered, and those
+/// contribute equally. So this method simply returns 1.
+pub(crate) fn box_kernel(_x: f32) -> f32 {
+ 1.0
+}
+
+// Sample the rows of the supplied image using the provided filter.
+// The height of the image remains unchanged.
+// ```new_width``` is the desired width of the new image
+// ```filter``` is the filter to use for sampling.
+// ```image``` is not necessarily Rgba and the order of channels is passed through.
+fn horizontal_sample<P, S>(
+ image: &Rgba32FImage,
+ new_width: u32,
+ filter: &mut Filter,
+) -> ImageBuffer<P, Vec<S>>
+where
+ P: Pixel<Subpixel = S> + 'static,
+ S: Primitive + 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(new_width, height);
+ let mut ws = Vec::new();
+
+ let max: f32 = NumCast::from(S::DEFAULT_MAX_VALUE).unwrap();
+ let min: f32 = NumCast::from(S::DEFAULT_MIN_VALUE).unwrap();
+ let ratio = width as f32 / new_width as f32;
+ let sratio = if ratio < 1.0 { 1.0 } else { ratio };
+ let src_support = filter.support * sratio;
+
+ for outx in 0..new_width {
+ // Find the point in the input image corresponding to the centre
+ // of the current pixel in the output image.
+ let inputx = (outx as f32 + 0.5) * ratio;
+
+ // Left and right are slice bounds for the input pixels relevant
+ // to the output pixel we are calculating. Pixel x is relevant
+ // if and only if (x >= left) && (x < right).
+
+ // Invariant: 0 <= left < right <= width
+
+ let left = (inputx - src_support).floor() as i64;
+ let left = clamp(left, 0, <i64 as From<_>>::from(width) - 1) as u32;
+
+ let right = (inputx + src_support).ceil() as i64;
+ let right = clamp(
+ right,
+ <i64 as From<_>>::from(left) + 1,
+ <i64 as From<_>>::from(width),
+ ) as u32;
+
+ // Go back to left boundary of pixel, to properly compare with i
+ // below, as the kernel treats the centre of a pixel as 0.
+ let inputx = inputx - 0.5;
+
+ ws.clear();
+ let mut sum = 0.0;
+ for i in left..right {
+ let w = (filter.kernel)((i as f32 - inputx) / sratio);
+ ws.push(w);
+ sum += w;
+ }
+ ws.iter_mut().for_each(|w| *w /= sum);
+
+ for y in 0..height {
+ let mut t = (0.0, 0.0, 0.0, 0.0);
+
+ for (i, w) in ws.iter().enumerate() {
+ let p = image.get_pixel(left + i as u32, y);
+
+ #[allow(deprecated)]
+ let vec = p.channels4();
+
+ t.0 += vec.0 * w;
+ t.1 += vec.1 * w;
+ t.2 += vec.2 * w;
+ t.3 += vec.3 * w;
+ }
+
+ #[allow(deprecated)]
+ let t = Pixel::from_channels(
+ NumCast::from(FloatNearest(clamp(t.0, min, max))).unwrap(),
+ NumCast::from(FloatNearest(clamp(t.1, min, max))).unwrap(),
+ NumCast::from(FloatNearest(clamp(t.2, min, max))).unwrap(),
+ NumCast::from(FloatNearest(clamp(t.3, min, max))).unwrap(),
+ );
+
+ out.put_pixel(outx, y, t);
+ }
+ }
+
+ out
+}
+
+/// Linearly sample from an image using coordinates in [0, 1].
+pub fn sample_bilinear<P: Pixel>(
+ img: &impl GenericImageView<Pixel = P>,
+ u: f32,
+ v: f32,
+) -> Option<P> {
+ if ![u, v].iter().all(|c| (0.0..=1.0).contains(c)) {
+ return None;
+ }
+
+ let (w, h) = img.dimensions();
+ if w == 0 || h == 0 {
+ return None;
+ }
+
+ let ui = w as f32 * u - 0.5;
+ let vi = h as f32 * v - 0.5;
+ interpolate_bilinear(
+ img,
+ ui.max(0.).min((w - 1) as f32),
+ vi.max(0.).min((h - 1) as f32),
+ )
+}
+
+/// Sample from an image using coordinates in [0, 1], taking the nearest coordinate.
+pub fn sample_nearest<P: Pixel>(
+ img: &impl GenericImageView<Pixel = P>,
+ u: f32,
+ v: f32,
+) -> Option<P> {
+ if ![u, v].iter().all(|c| (0.0..=1.0).contains(c)) {
+ return None;
+ }
+
+ let (w, h) = img.dimensions();
+ let ui = w as f32 * u - 0.5;
+ let ui = ui.max(0.).min((w.saturating_sub(1)) as f32);
+
+ let vi = h as f32 * v - 0.5;
+ let vi = vi.max(0.).min((h.saturating_sub(1)) as f32);
+ interpolate_nearest(img, ui, vi)
+}
+
+/// Sample from an image using coordinates in [0, w-1] and [0, h-1], taking the
+/// nearest pixel.
+///
+/// Coordinates outside the image bounds will return `None`, however the
+/// behavior for points within half a pixel of the image bounds may change in
+/// the future.
+pub fn interpolate_nearest<P: Pixel>(
+ img: &impl GenericImageView<Pixel = P>,
+ x: f32,
+ y: f32,
+) -> Option<P> {
+ let (w, h) = img.dimensions();
+ if w == 0 || h == 0 {
+ return None;
+ }
+ if !(0.0..=((w - 1) as f32)).contains(&x) {
+ return None;
+ }
+ if !(0.0..=((h - 1) as f32)).contains(&y) {
+ return None;
+ }
+
+ Some(img.get_pixel(x.round() as u32, y.round() as u32))
+}
+
+/// Linearly sample from an image using coordinates in [0, w-1] and [0, h-1].
+pub fn interpolate_bilinear<P: Pixel>(
+ img: &impl GenericImageView<Pixel = P>,
+ x: f32,
+ y: f32,
+) -> Option<P> {
+ let (w, h) = img.dimensions();
+ if w == 0 || h == 0 {
+ return None;
+ }
+ if !(0.0..=((w - 1) as f32)).contains(&x) {
+ return None;
+ }
+ if !(0.0..=((h - 1) as f32)).contains(&y) {
+ return None;
+ }
+
+ let uf = x.floor();
+ let vf = y.floor();
+ let uc = (x + 1.).min((w - 1) as f32);
+ let vc = (y + 1.).min((h - 1) as f32);
+
+ // clamp coords to the range of the image
+ let coords = [[uf, vf], [uf, vc], [uc, vf], [uc, vc]];
+
+ assert!(coords
+ .iter()
+ .all(|&[u, v]| { img.in_bounds(u as u32, v as u32) }));
+ let samples = coords.map(|[u, v]| img.get_pixel(u as u32, v as u32));
+ assert!(P::CHANNEL_COUNT <= 4);
+
+ // convert samples to f32
+ // currently rgba is the largest one,
+ // so just store as many items as necessary,
+ // because there's not a simple way to be generic over all of them.
+ let [sff, sfc, scf, scc] = samples.map(|s| {
+ let mut out = [0.; 4];
+ for (i, c) in s.channels().iter().enumerate() {
+ out[i] = c.to_f32().unwrap();
+ }
+ out
+ });
+ // weights
+ let [ufw, vfw] = [x - uf, y - vf];
+ let [ucw, vcw] = [1. - ufw, 1. - vfw];
+
+ // https://en.wikipedia.org/wiki/Bilinear_interpolation#Weighted_mean
+ // the distance between pixels is 1 so there is no denominator
+ let wff = ucw * vcw;
+ let wfc = ucw * vfw;
+ let wcf = ufw * vcw;
+ let wcc = ufw * vfw;
+ assert!(f32::abs((wff + wfc + wcf + wcc) - 1.) < 1e-3);
+
+ // hack to get around not being able to construct a generic Pixel
+ let mut out = samples[0];
+ for (i, c) in out.channels_mut().iter_mut().enumerate() {
+ let v = wff * sff[i] + wfc * sfc[i] + wcf * scf[i] + wcc * scc[i];
+ // this rounding may introduce quantization errors,
+ // but cannot do anything about it.
+ *c = <P::Subpixel as NumCast>::from(v.round()).unwrap_or({
+ if v < 0.0 {
+ P::Subpixel::DEFAULT_MIN_VALUE
+ } else {
+ P::Subpixel::DEFAULT_MAX_VALUE
+ }
+ })
+ }
+ Some(out)
+}
+
+// Sample the columns of the supplied image using the provided filter.
+// The width of the image remains unchanged.
+// ```new_height``` is the desired height of the new image
+// ```filter``` is the filter to use for sampling.
+// The return value is not necessarily Rgba, the underlying order of channels in ```image``` is
+// preserved.
+fn vertical_sample<I, P, S>(image: &I, new_height: u32, filter: &mut Filter) -> Rgba32FImage
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S> + 'static,
+ S: Primitive + 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(width, new_height);
+ let mut ws = Vec::new();
+
+ let ratio = height as f32 / new_height as f32;
+ let sratio = if ratio < 1.0 { 1.0 } else { ratio };
+ let src_support = filter.support * sratio;
+
+ for outy in 0..new_height {
+ // For an explanation of this algorithm, see the comments
+ // in horizontal_sample.
+ let inputy = (outy as f32 + 0.5) * ratio;
+
+ let left = (inputy - src_support).floor() as i64;
+ let left = clamp(left, 0, <i64 as From<_>>::from(height) - 1) as u32;
+
+ let right = (inputy + src_support).ceil() as i64;
+ let right = clamp(
+ right,
+ <i64 as From<_>>::from(left) + 1,
+ <i64 as From<_>>::from(height),
+ ) as u32;
+
+ let inputy = inputy - 0.5;
+
+ ws.clear();
+ let mut sum = 0.0;
+ for i in left..right {
+ let w = (filter.kernel)((i as f32 - inputy) / sratio);
+ ws.push(w);
+ sum += w;
+ }
+ ws.iter_mut().for_each(|w| *w /= sum);
+
+ for x in 0..width {
+ let mut t = (0.0, 0.0, 0.0, 0.0);
+
+ for (i, w) in ws.iter().enumerate() {
+ let p = image.get_pixel(x, left + i as u32);
+
+ #[allow(deprecated)]
+ let (k1, k2, k3, k4) = p.channels4();
+ let vec: (f32, f32, f32, f32) = (
+ NumCast::from(k1).unwrap(),
+ NumCast::from(k2).unwrap(),
+ NumCast::from(k3).unwrap(),
+ NumCast::from(k4).unwrap(),
+ );
+
+ t.0 += vec.0 * w;
+ t.1 += vec.1 * w;
+ t.2 += vec.2 * w;
+ t.3 += vec.3 * w;
+ }
+
+ #[allow(deprecated)]
+ // This is not necessarily Rgba.
+ let t = Pixel::from_channels(t.0, t.1, t.2, t.3);
+
+ out.put_pixel(x, outy, t);
+ }
+ }
+
+ out
+}
+
+/// Local struct for keeping track of pixel sums for fast thumbnail averaging
+struct ThumbnailSum<S: Primitive + Enlargeable>(S::Larger, S::Larger, S::Larger, S::Larger);
+
+impl<S: Primitive + Enlargeable> ThumbnailSum<S> {
+ fn zeroed() -> Self {
+ ThumbnailSum(
+ S::Larger::zero(),
+ S::Larger::zero(),
+ S::Larger::zero(),
+ S::Larger::zero(),
+ )
+ }
+
+ fn sample_val(val: S) -> S::Larger {
+ <S::Larger as NumCast>::from(val).unwrap()
+ }
+
+ fn add_pixel<P: Pixel<Subpixel = S>>(&mut self, pixel: P) {
+ #[allow(deprecated)]
+ let pixel = pixel.channels4();
+ self.0 += Self::sample_val(pixel.0);
+ self.1 += Self::sample_val(pixel.1);
+ self.2 += Self::sample_val(pixel.2);
+ self.3 += Self::sample_val(pixel.3);
+ }
+}
+
+/// Resize the supplied image to the specific dimensions.
+///
+/// For downscaling, this method uses a fast integer algorithm where each source pixel contributes
+/// to exactly one target pixel. May give aliasing artifacts if new size is close to old size.
+///
+/// In case the current width is smaller than the new width or similar for the height, another
+/// strategy is used instead. For each pixel in the output, a rectangular region of the input is
+/// determined, just as previously. But when no input pixel is part of this region, the nearest
+/// pixels are interpolated instead.
+///
+/// For speed reasons, all interpolation is performed linearly over the colour values. It will not
+/// take the pixel colour spaces into account.
+pub fn thumbnail<I, P, S>(image: &I, new_width: u32, new_height: u32) -> ImageBuffer<P, Vec<S>>
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S> + 'static,
+ S: Primitive + Enlargeable + 'static,
+{
+ let (width, height) = image.dimensions();
+ let mut out = ImageBuffer::new(new_width, new_height);
+
+ let x_ratio = width as f32 / new_width as f32;
+ let y_ratio = height as f32 / new_height as f32;
+
+ for outy in 0..new_height {
+ let bottomf = outy as f32 * y_ratio;
+ let topf = bottomf + y_ratio;
+
+ let bottom = clamp(bottomf.ceil() as u32, 0, height - 1);
+ let top = clamp(topf.ceil() as u32, bottom, height);
+
+ for outx in 0..new_width {
+ let leftf = outx as f32 * x_ratio;
+ let rightf = leftf + x_ratio;
+
+ let left = clamp(leftf.ceil() as u32, 0, width - 1);
+ let right = clamp(rightf.ceil() as u32, left, width);
+
+ let avg = if bottom != top && left != right {
+ thumbnail_sample_block(image, left, right, bottom, top)
+ } else if bottom != top {
+ // && left == right
+ // In the first column we have left == 0 and right > ceil(y_scale) > 0 so this
+ // assertion can never trigger.
+ debug_assert!(
+ left > 0 && right > 0,
+ "First output column must have corresponding pixels"
+ );
+
+ let fraction_horizontal = (leftf.fract() + rightf.fract()) / 2.;
+ thumbnail_sample_fraction_horizontal(
+ image,
+ right - 1,
+ fraction_horizontal,
+ bottom,
+ top,
+ )
+ } else if left != right {
+ // && bottom == top
+ // In the first line we have bottom == 0 and top > ceil(x_scale) > 0 so this
+ // assertion can never trigger.
+ debug_assert!(
+ bottom > 0 && top > 0,
+ "First output row must have corresponding pixels"
+ );
+
+ let fraction_vertical = (topf.fract() + bottomf.fract()) / 2.;
+ thumbnail_sample_fraction_vertical(image, left, right, top - 1, fraction_vertical)
+ } else {
+ // bottom == top && left == right
+ let fraction_horizontal = (topf.fract() + bottomf.fract()) / 2.;
+ let fraction_vertical = (leftf.fract() + rightf.fract()) / 2.;
+
+ thumbnail_sample_fraction_both(
+ image,
+ right - 1,
+ fraction_horizontal,
+ top - 1,
+ fraction_vertical,
+ )
+ };
+
+ #[allow(deprecated)]
+ let pixel = Pixel::from_channels(avg.0, avg.1, avg.2, avg.3);
+ out.put_pixel(outx, outy, pixel);
+ }
+ }
+
+ out
+}
+
+/// Get a pixel for a thumbnail where the input window encloses at least a full pixel.
+fn thumbnail_sample_block<I, P, S>(
+ image: &I,
+ left: u32,
+ right: u32,
+ bottom: u32,
+ top: u32,
+) -> (S, S, S, S)
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S>,
+ S: Primitive + Enlargeable,
+{
+ let mut sum = ThumbnailSum::zeroed();
+
+ for y in bottom..top {
+ for x in left..right {
+ let k = image.get_pixel(x, y);
+ sum.add_pixel(k);
+ }
+ }
+
+ let n = <S::Larger as NumCast>::from((right - left) * (top - bottom)).unwrap();
+ let round = <S::Larger as NumCast>::from(n / NumCast::from(2).unwrap()).unwrap();
+ (
+ S::clamp_from((sum.0 + round) / n),
+ S::clamp_from((sum.1 + round) / n),
+ S::clamp_from((sum.2 + round) / n),
+ S::clamp_from((sum.3 + round) / n),
+ )
+}
+
+/// Get a thumbnail pixel where the input window encloses at least a vertical pixel.
+fn thumbnail_sample_fraction_horizontal<I, P, S>(
+ image: &I,
+ left: u32,
+ fraction_horizontal: f32,
+ bottom: u32,
+ top: u32,
+) -> (S, S, S, S)
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S>,
+ S: Primitive + Enlargeable,
+{
+ let fract = fraction_horizontal;
+
+ let mut sum_left = ThumbnailSum::zeroed();
+ let mut sum_right = ThumbnailSum::zeroed();
+ for x in bottom..top {
+ let k_left = image.get_pixel(left, x);
+ sum_left.add_pixel(k_left);
+
+ let k_right = image.get_pixel(left + 1, x);
+ sum_right.add_pixel(k_right);
+ }
+
+ // Now we approximate: left/n*(1-fract) + right/n*fract
+ let fact_right = fract / ((top - bottom) as f32);
+ let fact_left = (1. - fract) / ((top - bottom) as f32);
+
+ let mix_left_and_right = |leftv: S::Larger, rightv: S::Larger| {
+ <S as NumCast>::from(
+ fact_left * leftv.to_f32().unwrap() + fact_right * rightv.to_f32().unwrap(),
+ )
+ .expect("Average sample value should fit into sample type")
+ };
+
+ (
+ mix_left_and_right(sum_left.0, sum_right.0),
+ mix_left_and_right(sum_left.1, sum_right.1),
+ mix_left_and_right(sum_left.2, sum_right.2),
+ mix_left_and_right(sum_left.3, sum_right.3),
+ )
+}
+
+/// Get a thumbnail pixel where the input window encloses at least a horizontal pixel.
+fn thumbnail_sample_fraction_vertical<I, P, S>(
+ image: &I,
+ left: u32,
+ right: u32,
+ bottom: u32,
+ fraction_vertical: f32,
+) -> (S, S, S, S)
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S>,
+ S: Primitive + Enlargeable,
+{
+ let fract = fraction_vertical;
+
+ let mut sum_bot = ThumbnailSum::zeroed();
+ let mut sum_top = ThumbnailSum::zeroed();
+ for x in left..right {
+ let k_bot = image.get_pixel(x, bottom);
+ sum_bot.add_pixel(k_bot);
+
+ let k_top = image.get_pixel(x, bottom + 1);
+ sum_top.add_pixel(k_top);
+ }
+
+ // Now we approximate: bot/n*fract + top/n*(1-fract)
+ let fact_top = fract / ((right - left) as f32);
+ let fact_bot = (1. - fract) / ((right - left) as f32);
+
+ let mix_bot_and_top = |botv: S::Larger, topv: S::Larger| {
+ <S as NumCast>::from(fact_bot * botv.to_f32().unwrap() + fact_top * topv.to_f32().unwrap())
+ .expect("Average sample value should fit into sample type")
+ };
+
+ (
+ mix_bot_and_top(sum_bot.0, sum_top.0),
+ mix_bot_and_top(sum_bot.1, sum_top.1),
+ mix_bot_and_top(sum_bot.2, sum_top.2),
+ mix_bot_and_top(sum_bot.3, sum_top.3),
+ )
+}
+
+/// Get a single pixel for a thumbnail where the input window does not enclose any full pixel.
+fn thumbnail_sample_fraction_both<I, P, S>(
+ image: &I,
+ left: u32,
+ fraction_vertical: f32,
+ bottom: u32,
+ fraction_horizontal: f32,
+) -> (S, S, S, S)
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S>,
+ S: Primitive + Enlargeable,
+{
+ #[allow(deprecated)]
+ let k_bl = image.get_pixel(left, bottom).channels4();
+ #[allow(deprecated)]
+ let k_tl = image.get_pixel(left, bottom + 1).channels4();
+ #[allow(deprecated)]
+ let k_br = image.get_pixel(left + 1, bottom).channels4();
+ #[allow(deprecated)]
+ let k_tr = image.get_pixel(left + 1, bottom + 1).channels4();
+
+ let frac_v = fraction_vertical;
+ let frac_h = fraction_horizontal;
+
+ let fact_tr = frac_v * frac_h;
+ let fact_tl = frac_v * (1. - frac_h);
+ let fact_br = (1. - frac_v) * frac_h;
+ let fact_bl = (1. - frac_v) * (1. - frac_h);
+
+ let mix = |br: S, tr: S, bl: S, tl: S| {
+ <S as NumCast>::from(
+ fact_br * br.to_f32().unwrap()
+ + fact_tr * tr.to_f32().unwrap()
+ + fact_bl * bl.to_f32().unwrap()
+ + fact_tl * tl.to_f32().unwrap(),
+ )
+ .expect("Average sample value should fit into sample type")
+ };
+
+ (
+ mix(k_br.0, k_tr.0, k_bl.0, k_tl.0),
+ mix(k_br.1, k_tr.1, k_bl.1, k_tl.1),
+ mix(k_br.2, k_tr.2, k_bl.2, k_tl.2),
+ mix(k_br.3, k_tr.3, k_bl.3, k_tl.3),
+ )
+}
+
+/// Perform a 3x3 box filter on the supplied image.
+/// ```kernel``` is an array of the filter weights of length 9.
+pub fn filter3x3<I, P, S>(image: &I, kernel: &[f32]) -> ImageBuffer<P, Vec<S>>
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S> + 'static,
+ S: Primitive + 'static,
+{
+ // The kernel's input positions relative to the current pixel.
+ let taps: &[(isize, isize)] = &[
+ (-1, -1),
+ (0, -1),
+ (1, -1),
+ (-1, 0),
+ (0, 0),
+ (1, 0),
+ (-1, 1),
+ (0, 1),
+ (1, 1),
+ ];
+
+ let (width, height) = image.dimensions();
+
+ let mut out = ImageBuffer::new(width, height);
+
+ let max = S::DEFAULT_MAX_VALUE;
+ let max: f32 = NumCast::from(max).unwrap();
+
+ let sum = match kernel.iter().fold(0.0, |s, &item| s + item) {
+ x if x == 0.0 => 1.0,
+ sum => sum,
+ };
+ let sum = (sum, sum, sum, sum);
+
+ for y in 1..height - 1 {
+ for x in 1..width - 1 {
+ let mut t = (0.0, 0.0, 0.0, 0.0);
+
+ // TODO: There is no need to recalculate the kernel for each pixel.
+ // Only a subtract and addition is needed for pixels after the first
+ // in each row.
+ for (&k, &(a, b)) in kernel.iter().zip(taps.iter()) {
+ let k = (k, k, k, k);
+ let x0 = x as isize + a;
+ let y0 = y as isize + b;
+
+ let p = image.get_pixel(x0 as u32, y0 as u32);
+
+ #[allow(deprecated)]
+ let (k1, k2, k3, k4) = p.channels4();
+
+ let vec: (f32, f32, f32, f32) = (
+ NumCast::from(k1).unwrap(),
+ NumCast::from(k2).unwrap(),
+ NumCast::from(k3).unwrap(),
+ NumCast::from(k4).unwrap(),
+ );
+
+ t.0 += vec.0 * k.0;
+ t.1 += vec.1 * k.1;
+ t.2 += vec.2 * k.2;
+ t.3 += vec.3 * k.3;
+ }
+
+ let (t1, t2, t3, t4) = (t.0 / sum.0, t.1 / sum.1, t.2 / sum.2, t.3 / sum.3);
+
+ #[allow(deprecated)]
+ let t = Pixel::from_channels(
+ NumCast::from(clamp(t1, 0.0, max)).unwrap(),
+ NumCast::from(clamp(t2, 0.0, max)).unwrap(),
+ NumCast::from(clamp(t3, 0.0, max)).unwrap(),
+ NumCast::from(clamp(t4, 0.0, max)).unwrap(),
+ );
+
+ out.put_pixel(x, y, t);
+ }
+ }
+
+ out
+}
+
+/// Resize the supplied image to the specified dimensions.
+/// ```nwidth``` and ```nheight``` are the new dimensions.
+/// ```filter``` is the sampling filter to use.
+pub fn resize<I: GenericImageView>(
+ image: &I,
+ nwidth: u32,
+ nheight: u32,
+ filter: FilterType,
+) -> ImageBuffer<I::Pixel, Vec<<I::Pixel as Pixel>::Subpixel>>
+where
+ I::Pixel: 'static,
+ <I::Pixel as Pixel>::Subpixel: 'static,
+{
+ // check if the new dimensions are the same as the old. if they are, make a copy instead of resampling
+ if (nwidth, nheight) == image.dimensions() {
+ let mut tmp = ImageBuffer::new(image.width(), image.height());
+ tmp.copy_from(image, 0, 0).unwrap();
+ return tmp;
+ }
+
+ let mut method = match filter {
+ FilterType::Nearest => Filter {
+ kernel: Box::new(box_kernel),
+ support: 0.0,
+ },
+ FilterType::Triangle => Filter {
+ kernel: Box::new(triangle_kernel),
+ support: 1.0,
+ },
+ FilterType::CatmullRom => Filter {
+ kernel: Box::new(catmullrom_kernel),
+ support: 2.0,
+ },
+ FilterType::Gaussian => Filter {
+ kernel: Box::new(gaussian_kernel),
+ support: 3.0,
+ },
+ FilterType::Lanczos3 => Filter {
+ kernel: Box::new(lanczos3_kernel),
+ support: 3.0,
+ },
+ };
+
+ // Note: tmp is not necessarily actually Rgba
+ let tmp: Rgba32FImage = vertical_sample(image, nheight, &mut method);
+ horizontal_sample(&tmp, nwidth, &mut method)
+}
+
+/// Performs a Gaussian blur on the supplied image.
+/// ```sigma``` is a measure of how much to blur by.
+pub fn blur<I: GenericImageView>(
+ image: &I,
+ sigma: f32,
+) -> ImageBuffer<I::Pixel, Vec<<I::Pixel as Pixel>::Subpixel>>
+where
+ I::Pixel: 'static,
+{
+ let sigma = if sigma <= 0.0 { 1.0 } else { sigma };
+
+ let mut method = Filter {
+ kernel: Box::new(|x| gaussian(x, sigma)),
+ support: 2.0 * sigma,
+ };
+
+ let (width, height) = image.dimensions();
+
+ // Keep width and height the same for horizontal and
+ // vertical sampling.
+ // Note: tmp is not necessarily actually Rgba
+ let tmp: Rgba32FImage = vertical_sample(image, height, &mut method);
+ horizontal_sample(&tmp, width, &mut method)
+}
+
+/// Performs an unsharpen mask on the supplied image.
+/// ```sigma``` is the amount to blur the image by.
+/// ```threshold``` is the threshold for minimal brightness change that will be sharpened.
+///
+/// See <https://en.wikipedia.org/wiki/Unsharp_masking#Digital_unsharp_masking>
+pub fn unsharpen<I, P, S>(image: &I, sigma: f32, threshold: i32) -> ImageBuffer<P, Vec<S>>
+where
+ I: GenericImageView<Pixel = P>,
+ P: Pixel<Subpixel = S> + 'static,
+ S: Primitive + 'static,
+{
+ let mut tmp = blur(image, sigma);
+
+ let max = S::DEFAULT_MAX_VALUE;
+ let max: i32 = NumCast::from(max).unwrap();
+ let (width, height) = image.dimensions();
+
+ for y in 0..height {
+ for x in 0..width {
+ let a = image.get_pixel(x, y);
+ let b = tmp.get_pixel_mut(x, y);
+
+ let p = a.map2(b, |c, d| {
+ let ic: i32 = NumCast::from(c).unwrap();
+ let id: i32 = NumCast::from(d).unwrap();
+
+ let diff = (ic - id).abs();
+
+ if diff > threshold {
+ let e = clamp(ic + diff, 0, max); // FIXME what does this do for f32? clamp 0-1 integers??
+
+ NumCast::from(e).unwrap()
+ } else {
+ c
+ }
+ });
+
+ *b = p;
+ }
+ }
+
+ tmp
+}
+
+#[cfg(test)]
+mod tests {
+ use super::{resize, sample_bilinear, sample_nearest, FilterType};
+ use crate::{GenericImageView, ImageBuffer, RgbImage};
+ #[cfg(feature = "benchmarks")]
+ use test;
+
+ #[bench]
+ #[cfg(all(feature = "benchmarks", feature = "png"))]
+ fn bench_resize(b: &mut test::Bencher) {
+ use std::path::Path;
+ let img = crate::open(&Path::new("./examples/fractal.png")).unwrap();
+ b.iter(|| {
+ test::black_box(resize(&img, 200, 200, FilterType::Nearest));
+ });
+ b.bytes = 800 * 800 * 3 + 200 * 200 * 3;
+ }
+
+ #[test]
+ #[cfg(feature = "png")]
+ fn test_resize_same_size() {
+ use std::path::Path;
+ let img = crate::open(&Path::new("./examples/fractal.png")).unwrap();
+ let resize = img.resize(img.width(), img.height(), FilterType::Triangle);
+ assert!(img.pixels().eq(resize.pixels()))
+ }
+
+ #[test]
+ #[cfg(feature = "png")]
+ fn test_sample_bilinear() {
+ use std::path::Path;
+ let img = crate::open(&Path::new("./examples/fractal.png")).unwrap();
+ assert!(sample_bilinear(&img, 0., 0.).is_some());
+ assert!(sample_bilinear(&img, 1., 0.).is_some());
+ assert!(sample_bilinear(&img, 0., 1.).is_some());
+ assert!(sample_bilinear(&img, 1., 1.).is_some());
+ assert!(sample_bilinear(&img, 0.5, 0.5).is_some());
+
+ assert!(sample_bilinear(&img, 1.2, 0.5).is_none());
+ assert!(sample_bilinear(&img, 0.5, 1.2).is_none());
+ assert!(sample_bilinear(&img, 1.2, 1.2).is_none());
+
+ assert!(sample_bilinear(&img, -0.1, 0.2).is_none());
+ assert!(sample_bilinear(&img, 0.2, -0.1).is_none());
+ assert!(sample_bilinear(&img, -0.1, -0.1).is_none());
+ }
+ #[test]
+ #[cfg(feature = "png")]
+ fn test_sample_nearest() {
+ use std::path::Path;
+ let img = crate::open(&Path::new("./examples/fractal.png")).unwrap();
+ assert!(sample_nearest(&img, 0., 0.).is_some());
+ assert!(sample_nearest(&img, 1., 0.).is_some());
+ assert!(sample_nearest(&img, 0., 1.).is_some());
+ assert!(sample_nearest(&img, 1., 1.).is_some());
+ assert!(sample_nearest(&img, 0.5, 0.5).is_some());
+
+ assert!(sample_nearest(&img, 1.2, 0.5).is_none());
+ assert!(sample_nearest(&img, 0.5, 1.2).is_none());
+ assert!(sample_nearest(&img, 1.2, 1.2).is_none());
+
+ assert!(sample_nearest(&img, -0.1, 0.2).is_none());
+ assert!(sample_nearest(&img, 0.2, -0.1).is_none());
+ assert!(sample_nearest(&img, -0.1, -0.1).is_none());
+ }
+ #[test]
+ fn test_sample_bilinear_correctness() {
+ use crate::Rgba;
+ let img = ImageBuffer::from_fn(2, 2, |x, y| match (x, y) {
+ (0, 0) => Rgba([255, 0, 0, 0]),
+ (0, 1) => Rgba([0, 255, 0, 0]),
+ (1, 0) => Rgba([0, 0, 255, 0]),
+ (1, 1) => Rgba([0, 0, 0, 255]),
+ _ => panic!(),
+ });
+ assert_eq!(sample_bilinear(&img, 0.5, 0.5), Some(Rgba([64; 4])));
+ assert_eq!(sample_bilinear(&img, 0.0, 0.0), Some(Rgba([255, 0, 0, 0])));
+ assert_eq!(sample_bilinear(&img, 0.0, 1.0), Some(Rgba([0, 255, 0, 0])));
+ assert_eq!(sample_bilinear(&img, 1.0, 0.0), Some(Rgba([0, 0, 255, 0])));
+ assert_eq!(sample_bilinear(&img, 1.0, 1.0), Some(Rgba([0, 0, 0, 255])));
+
+ assert_eq!(
+ sample_bilinear(&img, 0.5, 0.0),
+ Some(Rgba([128, 0, 128, 0]))
+ );
+ assert_eq!(
+ sample_bilinear(&img, 0.0, 0.5),
+ Some(Rgba([128, 128, 0, 0]))
+ );
+ assert_eq!(
+ sample_bilinear(&img, 0.5, 1.0),
+ Some(Rgba([0, 128, 0, 128]))
+ );
+ assert_eq!(
+ sample_bilinear(&img, 1.0, 0.5),
+ Some(Rgba([0, 0, 128, 128]))
+ );
+ }
+ #[test]
+ fn test_sample_nearest_correctness() {
+ use crate::Rgba;
+ let img = ImageBuffer::from_fn(2, 2, |x, y| match (x, y) {
+ (0, 0) => Rgba([255, 0, 0, 0]),
+ (0, 1) => Rgba([0, 255, 0, 0]),
+ (1, 0) => Rgba([0, 0, 255, 0]),
+ (1, 1) => Rgba([0, 0, 0, 255]),
+ _ => panic!(),
+ });
+
+ assert_eq!(sample_nearest(&img, 0.0, 0.0), Some(Rgba([255, 0, 0, 0])));
+ assert_eq!(sample_nearest(&img, 0.0, 1.0), Some(Rgba([0, 255, 0, 0])));
+ assert_eq!(sample_nearest(&img, 1.0, 0.0), Some(Rgba([0, 0, 255, 0])));
+ assert_eq!(sample_nearest(&img, 1.0, 1.0), Some(Rgba([0, 0, 0, 255])));
+
+ assert_eq!(sample_nearest(&img, 0.5, 0.5), Some(Rgba([0, 0, 0, 255])));
+ assert_eq!(sample_nearest(&img, 0.5, 0.0), Some(Rgba([0, 0, 255, 0])));
+ assert_eq!(sample_nearest(&img, 0.0, 0.5), Some(Rgba([0, 255, 0, 0])));
+ assert_eq!(sample_nearest(&img, 0.5, 1.0), Some(Rgba([0, 0, 0, 255])));
+ assert_eq!(sample_nearest(&img, 1.0, 0.5), Some(Rgba([0, 0, 0, 255])));
+ }
+
+ #[bench]
+ #[cfg(all(feature = "benchmarks", feature = "tiff"))]
+ fn bench_resize_same_size(b: &mut test::Bencher) {
+ let path = concat!(
+ env!("CARGO_MANIFEST_DIR"),
+ "/tests/images/tiff/testsuite/mandrill.tiff"
+ );
+ let image = crate::open(path).unwrap();
+ b.iter(|| {
+ test::black_box(image.resize(image.width(), image.height(), FilterType::CatmullRom));
+ });
+ b.bytes = (image.width() * image.height() * 3) as u64;
+ }
+
+ #[test]
+ fn test_issue_186() {
+ let img: RgbImage = ImageBuffer::new(100, 100);
+ let _ = resize(&img, 50, 50, FilterType::Lanczos3);
+ }
+
+ #[bench]
+ #[cfg(all(feature = "benchmarks", feature = "tiff"))]
+ fn bench_thumbnail(b: &mut test::Bencher) {
+ let path = concat!(
+ env!("CARGO_MANIFEST_DIR"),
+ "/tests/images/tiff/testsuite/mandrill.tiff"
+ );
+ let image = crate::open(path).unwrap();
+ b.iter(|| {
+ test::black_box(image.thumbnail(256, 256));
+ });
+ b.bytes = 512 * 512 * 4 + 256 * 256 * 4;
+ }
+
+ #[bench]
+ #[cfg(all(feature = "benchmarks", feature = "tiff"))]
+ fn bench_thumbnail_upsize(b: &mut test::Bencher) {
+ let path = concat!(
+ env!("CARGO_MANIFEST_DIR"),
+ "/tests/images/tiff/testsuite/mandrill.tiff"
+ );
+ let image = crate::open(path).unwrap().thumbnail(256, 256);
+ b.iter(|| {
+ test::black_box(image.thumbnail(512, 512));
+ });
+ b.bytes = 512 * 512 * 4 + 256 * 256 * 4;
+ }
+
+ #[bench]
+ #[cfg(all(feature = "benchmarks", feature = "tiff"))]
+ fn bench_thumbnail_upsize_irregular(b: &mut test::Bencher) {
+ let path = concat!(
+ env!("CARGO_MANIFEST_DIR"),
+ "/tests/images/tiff/testsuite/mandrill.tiff"
+ );
+ let image = crate::open(path).unwrap().thumbnail(193, 193);
+ b.iter(|| {
+ test::black_box(image.thumbnail(256, 256));
+ });
+ b.bytes = 193 * 193 * 4 + 256 * 256 * 4;
+ }
+
+ #[test]
+ #[cfg(feature = "png")]
+ fn resize_transparent_image() {
+ use super::FilterType::{CatmullRom, Gaussian, Lanczos3, Nearest, Triangle};
+ use crate::imageops::crop_imm;
+ use crate::RgbaImage;
+
+ fn assert_resize(image: &RgbaImage, filter: FilterType) {
+ let resized = resize(image, 16, 16, filter);
+ let cropped = crop_imm(&resized, 5, 5, 6, 6).to_image();
+ for pixel in cropped.pixels() {
+ let alpha = pixel.0[3];
+ assert!(
+ alpha != 254 && alpha != 253,
+ "alpha value: {}, {:?}",
+ alpha,
+ filter
+ );
+ }
+ }
+
+ let path = concat!(
+ env!("CARGO_MANIFEST_DIR"),
+ "/tests/images/png/transparency/tp1n3p08.png"
+ );
+ let img = crate::open(path).unwrap();
+ let rgba8 = img.as_rgba8().unwrap();
+ let filters = &[Nearest, Triangle, CatmullRom, Gaussian, Lanczos3];
+ for filter in filters {
+ assert_resize(rgba8, *filter);
+ }
+ }
+
+ #[test]
+ fn bug_1600() {
+ let image = crate::RgbaImage::from_raw(629, 627, vec![255; 629 * 627 * 4]).unwrap();
+ let result = resize(&image, 22, 22, FilterType::Lanczos3);
+ assert!(result.into_raw().into_iter().any(|c| c != 0));
+ }
+}