Add large image benchmark

Author: veluca93

Cargo.toml

@@ -22,5 +22,9 @@ criterion = "0.3"
 name = "decoding_benchmark"
 harness = false
 
+[[bench]]
+name = "large_image"
+harness = false
+
 [features]
 default = ["rayon"]

benches/large_image.jpg

@@ -0,0 +1,18 @@
+extern crate criterion;
+extern crate jpeg_decoder;
+
+use criterion::{black_box, Criterion};
+
+use jpeg_decoder as jpeg;
+
+fn read_image(image: &[u8]) -> Vec<u8> {
+    jpeg::Decoder::new(black_box(image)).decode().unwrap()
+}
+
+fn main() {
+    let mut c = Criterion::default().configure_from_args();
+    c.bench_function("decode a 2268x1512 JPEG", |b| {
+        b.iter(|| read_image(include_bytes!("large_image.jpg")))
+    });
+    c.final_summary();
+}