更新libclamav库1.0.0版本

clamav/libclamav_rust/.cargo/vendor/image/README.md

@@ -0,0 +1,247 @@
+# Image
+[![crates.io](https://img.shields.io/crates/v/image.svg)](https://crates.io/crates/image)
+[![Documentation](https://docs.rs/image/badge.svg)](https://docs.rs/image)
+[![Build Status](https://github.com/image-rs/image/workflows/Rust%20CI/badge.svg)](https://github.com/image-rs/image/actions)
+[![Gitter](https://badges.gitter.im/image-rs/image.svg)](https://gitter.im/image-rs/image?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge)
+
+Maintainers: [@HeroicKatora](https://github.com/HeroicKatora), [@fintelia](https://github.com/fintelia)
+
+[How to contribute](https://github.com/image-rs/organization/blob/master/CONTRIBUTING.md)
+
+## An Image Processing Library
+
+This crate provides basic image processing functions and methods for converting to and from various image formats.
+
+All image processing functions provided operate on types that implement the `GenericImageView` and `GenericImage` traits and return an `ImageBuffer`.
+
+## Supported Image Formats
+
+`image` provides implementations of common image format encoders and decoders.
+
+| Format | Decoding | Encoding |
+| ------ | -------- | -------- |
+| PNG    | All supported color types | Same as decoding |
+| JPEG   | Baseline and progressive | Baseline JPEG |
+| GIF    | Yes | Yes |
+| BMP    | Yes | Rgb8, Rgba8, Gray8, GrayA8 |
+| ICO    | Yes | Yes |
+| TIFF   | Baseline(no fax support) + LZW + PackBits | Rgb8, Rgba8, Gray8 |
+| WebP   | Yes | Rgb8, Rgba8 \* |
+| AVIF   | Only 8-bit \*\* | Lossy |
+| PNM    | PBM, PGM, PPM, standard PAM | Yes |
+| DDS    | DXT1, DXT3, DXT5 | No |
+| TGA    | Yes | Rgb8, Rgba8, Bgr8, Bgra8, Gray8, GrayA8 |
+| OpenEXR  | Rgb32F, Rgba32F (no dwa compression) | Rgb32F, Rgba32F (no dwa compression) |
+| farbfeld | Yes | Yes |
+
+- \* Requires the `webp-encoder` feature, uses the libwebp C library.
+- \*\* Requires the `avif-decoder` feature, uses the libdav1d C library.
+
+### The [`ImageDecoder`](https://docs.rs/image/*/image/trait.ImageDecoder.html) and [`ImageDecoderRect`](https://docs.rs/image/*/image/trait.ImageDecoderRect.html) Traits
+
+All image format decoders implement the `ImageDecoder` trait which provide
+basic methods for getting image metadata and decoding images. Some formats
+additionally provide `ImageDecoderRect` implementations which allow for
+decoding only part of an image at once.
+
+The most important methods for decoders are...
++ **dimensions**: Return a tuple containing the width and height of the image.
++ **color_type**: Return the color type of the image data produced by this decoder.
++ **read_image**: Decode the entire image into a slice of bytes.
+
+## Pixels
+
+`image` provides the following pixel types:
++ **Rgb**: RGB pixel
++ **Rgba**: RGBA pixel
++ **Luma**: Grayscale pixel
++ **LumaA**: Grayscale with alpha
+
+All pixels are parameterised by their component type.
+
+## Images
+Individual pixels within images are indexed with (0,0) at the top left corner. 
+### The [`GenericImageView`](https://docs.rs/image/*/image/trait.GenericImageView.html) and [`GenericImage`](https://docs.rs/image/*/image/trait.GenericImage.html) Traits
+
+Traits that provide methods for inspecting (`GenericImageView`) and manipulating (`GenericImage`) images, parameterised over the image's pixel type.
+
+Some of these methods for `GenericImageView` are...
++ **dimensions**: Return a tuple containing the width and height of the image.
++ **get_pixel**: Returns the pixel located at (x, y).
++ **pixels**: Returns an Iterator over the pixels of this image.
+
+While some of the methods for `GenericImage` are...
++ **put_pixel**: Put a pixel at location (x, y).
++ **copy_from**: Copies all of the pixels from another image into this image.
+
+### Representation of Images
+`image` provides two main ways of representing image data:
+
+#### [`ImageBuffer`](https://docs.rs/image/*/image/struct.ImageBuffer.html)
+An image parameterised by its Pixel types, represented by a width and height and a vector of pixels. It provides direct access to its pixels and implements the `GenericImageView` and `GenericImage` traits.
+
+```rust
+use image::{GenericImage, GenericImageView, ImageBuffer, RgbImage};
+
+// Construct a new RGB ImageBuffer with the specified width and height.
+let img: RgbImage = ImageBuffer::new(512, 512);
+
+// Construct a new by repeated calls to the supplied closure.
+let mut img = ImageBuffer::from_fn(512, 512, |x, y| {
+    if x % 2 == 0 {
+        image::Luma([0u8])
+    } else {
+        image::Luma([255u8])
+    }
+});
+
+// Obtain the image's width and height.
+let (width, height) = img.dimensions();
+
+// Access the pixel at coordinate (100, 100).
+let pixel = img[(100, 100)];
+
+// Or use the `get_pixel` method from the `GenericImage` trait.
+let pixel = *img.get_pixel(100, 100);
+
+// Put a pixel at coordinate (100, 100).
+img.put_pixel(100, 100, pixel);
+
+// Iterate over all pixels in the image.
+for pixel in img.pixels() {
+    // Do something with pixel.
+}
+```
+
+#### [`DynamicImage`](https://docs.rs/image/*/image/enum.DynamicImage.html)
+A `DynamicImage` is an enumeration over all supported `ImageBuffer<P>` types.
+Its exact image type is determined at runtime. It is the type returned when opening an image.
+For convenience `DynamicImage` reimplements all image processing functions.
+
+`DynamicImage` implement the `GenericImageView` and `GenericImage` traits for RGBA pixels.
+
+#### [`SubImage`](https://docs.rs/image/*/image/struct.SubImage.html)
+A view into another image, delimited by the coordinates of a rectangle.
+The coordinates given set the position of the top left corner of the rectangle.
+This is used to perform image processing functions on a subregion of an image.
+
+```rust
+use image::{GenericImageView, ImageBuffer, RgbImage, imageops};
+
+let mut img: RgbImage = ImageBuffer::new(512, 512);
+let subimg = imageops::crop(&mut img, 0, 0, 100, 100);
+
+assert!(subimg.dimensions() == (100, 100));
+```
+
+## Image Processing Functions
+These are the functions defined in the `imageops` module. All functions operate on types that implement the `GenericImage` trait.
+Note that some of the functions are very slow in debug mode. Make sure to use release mode if you experience any performance issues.
+
++ **blur**: Performs a Gaussian blur on the supplied image.
++ **brighten**: Brighten the supplied image.
++ **huerotate**: Hue rotate the supplied image by degrees.
++ **contrast**: Adjust the contrast of the supplied image.
++ **crop**: Return a mutable view into an image.
++ **filter3x3**: Perform a 3x3 box filter on the supplied image.
++ **flip_horizontal**: Flip an image horizontally.
++ **flip_vertical**: Flip an image vertically.
++ **grayscale**: Convert the supplied image to grayscale.
++ **invert**: Invert each pixel within the supplied image This function operates in place.
++ **resize**: Resize the supplied image to the specified dimensions.
++ **rotate180**: Rotate an image 180 degrees clockwise.
++ **rotate270**: Rotate an image 270 degrees clockwise.
++ **rotate90**: Rotate an image 90 degrees clockwise.
++ **unsharpen**: Performs an unsharpen mask on the supplied image.
+
+For more options, see the [`imageproc`](https://crates.io/crates/imageproc) crate.
+
+## Examples
+### Opening and Saving Images
+
+`image` provides the `open` function for opening images from a path.  The image
+format is determined from the path's file extension. An `io` module provides a
+reader which offer some more control.
+
+```rust,no_run
+use image::GenericImageView;
+
+fn main() {
+    // Use the open function to load an image from a Path.
+    // `open` returns a `DynamicImage` on success.
+    let img = image::open("tests/images/jpg/progressive/cat.jpg").unwrap();
+
+    // The dimensions method returns the images width and height.
+    println!("dimensions {:?}", img.dimensions());
+
+    // The color method returns the image's `ColorType`.
+    println!("{:?}", img.color());
+
+    // Write the contents of this image to the Writer in PNG format.
+    img.save("test.png").unwrap();
+}
+```
+
+### Generating Fractals
+
+```rust,no_run
+//! An example of generating julia fractals.
+fn main() {
+    let imgx = 800;
+    let imgy = 800;
+
+    let scalex = 3.0 / imgx as f32;
+    let scaley = 3.0 / imgy as f32;
+
+    // Create a new ImgBuf with width: imgx and height: imgy
+    let mut imgbuf = image::ImageBuffer::new(imgx, imgy);
+
+    // Iterate over the coordinates and pixels of the image
+    for (x, y, pixel) in imgbuf.enumerate_pixels_mut() {
+        let r = (0.3 * x as f32) as u8;
+        let b = (0.3 * y as f32) as u8;
+        *pixel = image::Rgb([r, 0, b]);
+    }
+
+    // A redundant loop to demonstrate reading image data
+    for x in 0..imgx {
+        for y in 0..imgy {
+            let cx = y as f32 * scalex - 1.5;
+            let cy = x as f32 * scaley - 1.5;
+
+            let c = num_complex::Complex::new(-0.4, 0.6);
+            let mut z = num_complex::Complex::new(cx, cy);
+
+            let mut i = 0;
+            while i < 255 && z.norm() <= 2.0 {
+                z = z * z + c;
+                i += 1;
+            }
+
+            let pixel = imgbuf.get_pixel_mut(x, y);
+            let image::Rgb(data) = *pixel;
+            *pixel = image::Rgb([data[0], i as u8, data[2]]);
+        }
+    }
+
+    // Save the image as “fractal.png”, the format is deduced from the path
+    imgbuf.save("fractal.png").unwrap();
+}
+```
+
+Example output:
+
+<img src="examples/fractal.png" alt="A Julia Fractal, c: -0.4 + 0.6i" width="500" />
+
+### Writing raw buffers
+If the high level interface is not needed because the image was obtained by other means, `image` provides the function `save_buffer` to save a buffer to a file.
+
+```rust,no_run
+fn main() {
+
+    let buffer: &[u8] = unimplemented!(); // Generate the image data
+
+    // Save the buffer as "image.png"
+    image::save_buffer("image.png", buffer, 800, 600, image::ColorType::Rgb8).unwrap()
+}
+```