chore: simplify the code in image.rs

src/image.rs

@@ -4,8 +4,8 @@ use std::io::Write;
 use flate2::write::GzDecoder;
 use image::error::ImageResult;
 use image::load_from_memory;
-use image::{DynamicImage, ImageBuffer, ImageOutputFormat, Rgba};
-use image::{GenericImage, Pixel};
+use image::GenericImage;
+use image::{DynamicImage, ImageOutputFormat::Png, Rgba, RgbaImage};
 use rlottie::{Animation, Surface};
 
 use crate::error::Error;
@@ -17,7 +17,7 @@ fn alpha_composit(pixel: &mut Rgba<u8>, color: [i32; 3]) {
     pixel[3] = 255;
 }
 
-fn trans_flag(img: &mut ImageBuffer<Rgba<u8>, Vec<u8>>) {
+fn trans_flag(img: &mut RgbaImage) {
     const COLOR: [[i32; 3]; 5] = [
         [0x5b, 0xce, 0xfa],
         [0xf5, 0xa9, 0xb8],
@@ -45,10 +45,7 @@ fn trans_flag(img: &mut ImageBuffer<Rgba<u8>, Vec<u8>>) {
     });
 }
 
-fn square_image<P: Pixel<Subpixel = u8> + 'static>(
-    img: &mut ImageBuffer<P, Vec<u8>>,
-    align: &str,
-) -> Option<ImageBuffer<P, Vec<u8>>> {
+fn square_image(img: &mut RgbaImage, align: &str) -> Option<RgbaImage> {
     let height = img.height();
     let width = img.width();
     if width >= height {
@@ -88,7 +85,7 @@ pub fn image_to_png(data: &mut Vec<u8>, background: &str, align: Option<&str>) -
         }
     }
 
-    DynamicImage::ImageRgba8(rgba).write_to(&mut Cursor::new(data), ImageOutputFormat::Png)
+    DynamicImage::ImageRgba8(rgba).write_to(&mut Cursor::new(data), Png)
 }
 
 pub fn tgs_to_png(data: Vec<u8>) -> Result<Vec<u8>, Error> {
@@ -99,13 +96,12 @@ pub fn tgs_to_png(data: Vec<u8>) -> Result<Vec<u8>, Error> {
     let mut surface = Surface::new(animation.size());
     animation.render(0, &mut surface);
 
-    let mut rgba = ImageBuffer::<Rgba<u8>, _>::new(surface.width() as _, surface.height() as _);
+    let mut rgba = RgbaImage::new(surface.width() as _, surface.height() as _);
     for (x, y) in rgba.pixels_mut().zip(surface.data()) {
         (x[0], x[1], x[2], x[3]) = (y.r, y.g, y.b, y.a);
     }
 
     let mut png_data = Vec::new();
-    DynamicImage::ImageRgba8(rgba)
-        .write_to(&mut Cursor::new(&mut png_data), ImageOutputFormat::Png)?;
+    DynamicImage::ImageRgba8(rgba).write_to(&mut Cursor::new(&mut png_data), Png)?;
     Ok(png_data)
 }