X-Git-Url: https://git.nihav.org/?a=blobdiff_plain;f=nihav-core%2Fsrc%2Fdsp%2Fdct.rs;h=b3415e395971b694d14a4a3ee7614bb0a35d5829;hb=629a102529407457851701428cc192ba2aa1b1f0;hp=1131ff646b5c09c30111984c41b622d5cbf9e6af;hpb=5a990253d72311958164c0680a6614b52d5cecca;p=nihav.git

diff --git a/nihav-core/src/dsp/dct.rs b/nihav-core/src/dsp/dct.rs
index 1131ff6..b3415e3 100644
--- a/nihav-core/src/dsp/dct.rs
+++ b/nihav-core/src/dsp/dct.rs
@@ -48,7 +48,7 @@ impl DCT {
             perm_tab.push(0); // size = 1
             perm_tab.push(0); // size = 2
             perm_tab.push(1);
-            for blen in 2..bits+1 {
+            for blen in 2..=bits {
                 let ssize = 1 << blen;
                 for i in 0..ssize { perm_tab.push(swp_idx(i, blen)); }
             }
@@ -66,7 +66,7 @@ impl DCT {
                     tab.push((consts::PI / 8.0).sin()); // size = 1
                     tab.push((consts::PI / 8.0).cos());
                     if bits > 1 {
-                        for blen in 1..bits+1 {
+                        for blen in 1..=bits {
                             let tsize = 1 << blen;
                             let base = consts::PI / ((tsize * 8) as f32);
                             for i in 0..tsize {
@@ -153,7 +153,7 @@ fn reverse_bits(inval: u32) -> u32 {
     let mut val = inval;
     for _ in 0..8 {
         ret = (ret << 4) | (REV_TAB[(val & 0xF) as usize] as u32);
-        val = val >> 4;
+        val >>= 4;
     }
     ret
 }
@@ -163,7 +163,7 @@ fn swp_idx(idx: usize, bits: u32) -> usize {
     s >> (32 - bits)
 }
 
-fn gen_swaps_for_perm(swaps: &mut Vec<usize>, perms: &Vec<usize>) {
+fn gen_swaps_for_perm(swaps: &mut Vec<usize>, perms: &[usize]) {
     let mut idx_arr: Vec<usize> = Vec::with_capacity(perms.len());
     for i in 0..perms.len() { idx_arr.push(i); }
     let mut run_size = 0;
@@ -186,12 +186,10 @@ fn gen_swaps_for_perm(swaps: &mut Vec<usize>, perms: &Vec<usize>) {
     }
 }
 
-fn swap_buf(buf: &mut [f32], swaps: &Vec<usize>) {
+fn swap_buf(buf: &mut [f32], swaps: &[usize]) {
     for (idx, nidx) in swaps.iter().enumerate() {
         if idx != *nidx {
-            let t      = buf[*nidx];
-            buf[*nidx] = buf[idx];
-            buf[idx]   = t;
+            buf.swap(*nidx, idx);
         }
     }
 }
@@ -395,9 +393,7 @@ fn dst_II_inplace(buf: &mut [f32], size: usize, step: usize, tab: &[f32], perm_t
     for i in 0..hsize {
         let idx0 = i * step;
         let idx1 = (size - 1 - i) * step;
-        let t = buf[idx1];
-        buf[idx1] = buf[idx0];
-        buf[idx0] = t;
+        buf.swap(idx0, idx1);
     }
 }
 
@@ -408,9 +404,7 @@ fn dct_III_inplace(buf: &mut [f32], size: usize, step: usize, tab: &[f32], perm_
     dct_III_inplace(buf,                   hsize, step, tab, perm_tab);
     dct_IV_inplace(&mut buf[step*hsize..], hsize, step, tab, perm_tab);
     for i in 0..(size >> 2) {
-        let t = buf[(size - 1 - i) * step];
-        buf[(size - 1 - i) * step] = buf[(hsize + i) * step];
-        buf[(hsize + i) * step] = t;
+        buf.swap((size - 1 - i) * step, (hsize + i) * step);
     }
     for i in 0..hsize {
         let i0 = buf[i * step] / consts::SQRT_2;
@@ -427,9 +421,7 @@ fn dst_III_inplace(buf: &mut [f32], size: usize, step: usize, tab: &[f32], perm_
     for i in 0..hsize {
         let idx0 = i * step;
         let idx1 = (size - 1 - i) * step;
-        let t = buf[idx1];
-        buf[idx1] = buf[idx0];
-        buf[idx0] = t;
+        buf.swap(idx0, idx1);
     }
     dct_III_inplace(buf, size, step, tab, perm_tab);
     for i in 0..hsize { buf[i * 2 * step + step] = -buf[i * 2 * step + step]; }
@@ -456,9 +448,7 @@ fn dct_IV_inplace(buf: &mut [f32], size: usize, step: usize, tab: &[f32], perm_t
     dct_II_inplace(buf,              hsize, step * 2, tab, perm_tab);
     dct_II_inplace(&mut buf[step..], hsize, step * 2, tab, perm_tab);
     for i in 0..(size >> 2) {
-        let t = buf[(size - 1 - i * 2) * step];
-        buf[(size - 1 - i * 2) * step] = buf[(i * 2 + 1) * step];
-        buf[(i * 2 + 1) * step] = t;
+        buf.swap((size - 1 - i * 2) * step, (i * 2 + 1) * step);
     }
     for i in (3..size).step_by(4) {
         buf[i] = -buf[i];