adds dct?

src/descriptors.rs

@@ -1,4 +1,5 @@
 use image::GenericImageView;
+use std::f64::consts::PI;
 
 pub trait Descriptor {
     fn info(&self) -> String {
@@ -10,16 +11,25 @@ pub trait Descriptor {
     }
 }
 
+fn median64<T: Ord + Copy>(values: &[T]) -> T {
+    let mut sorted_values = values.to_vec();
+    sorted_values.sort();
+    let len = sorted_values.len();
+    sorted_values[len/2]
+}
+
 pub struct Median;
 
 impl Descriptor for Median {
     fn describe(&self, img: image::DynamicImage) -> u64 {
-        let mut median: u64 = 0; //Average for now while i figure out sorting in rust
         let img = img.grayscale().thumbnail_exact(8, 8);
+        let mut values: [u8; 64] = [0; 64];
+        let mut i: usize = 0;
         for (_, _, pix) in img.pixels() {
-            median += pix[0] as u64;
+            values[i] = pix[0];
+            i = i+1;
         }
-        let median: u8 = (median/64) as u8;
+        let median = median64(&values);
         let mut mask: u64 = 0;
         img.save("debug.png").unwrap();
         for (_, _, pix) in img.pixels() {
@@ -32,3 +42,37 @@ impl Descriptor for Median {
     }
 }
 
+pub struct DCT;
+
+impl Descriptor for DCT {
+    fn describe(&self, img: image::DynamicImage) -> u64 {
+        let mut dct_values: [f64; 64] = [0.0; 64];
+        let img = img.grayscale().thumbnail_exact(8, 8);
+        let mut total_sum: f64 = 0.0;
+
+        for j in 0..7 {
+            for i in 0..7 {
+                let mut sum: f64 = 0.0;
+                let k = (i*8)+j;
+                for (x, y, pix) in img.pixels() {
+                    let n: f64 = ((y*8)+x).into();
+                    let pixel: i16 = pix[0] as i16 - 127;
+                    sum += pixel as f64 * (PI/64.0 * (n + 0.5) * k as f64).cos();
+                }
+                dct_values[k] = sum;
+                total_sum += sum;
+                //println!("{sum}");
+            }
+        }
+        total_sum /= 64.0;
+
+        let mut mask: u64 = 0;
+        for dct in dct_values {
+            if dct > 0.0 {
+                mask += 1
+            }
+            mask = mask << 1;
+        }
+        mask
+    }
+}

src/main.rs

@@ -1,4 +1,4 @@
-use descriptors::{Descriptor, Median};
+use descriptors::{Descriptor, Median, DCT};
 use std::collections::HashMap;
 use std::fs;
 
@@ -28,10 +28,10 @@ fn main() {
     }
 
     for (key, val) in map.iter() {
-        println!("{key}: {val}");
+        println!("{key: >15}: {val}\t {val:b}");
     }
 
     //Serialize hashmap with MessagePack:
     let serialized: Vec<u8> = rmp_serde::to_vec(&map).unwrap();
-    fs::write("map.messagepack",&serialized).unwrap();
+    //fs::write("map.messagepack",&serialized).unwrap();
 }