core/soundcvt: fix u8->i16 test

[nihav.git] / nihav-core / src / soundcvt / mod.rs

diff --git a/nihav-core/src/soundcvt/mod.rs b/nihav-core/src/soundcvt/mod.rs
index 154b59f22ee58e9e0130c50208dee93328c437d1..891a58a3933442d6d91a2e91192e74181acf62d2 100644 (file)
--- a/nihav-core/src/soundcvt/mod.rs
+++ b/nihav-core/src/soundcvt/mod.rs
@@ -139,7 +139,16 @@ impl FromFmt<f32> for i16 {
     fn cvt_from(val: f32) -> i16 { (val * 32768.0).min(32767.0).max(-32768.0) as i16 }
 }
 impl FromFmt<f32> for i32 {
-    fn cvt_from(val: f32) -> i32 { (val * 31.0f32.exp2()) as i32 }
+    fn cvt_from(val: f32) -> i32 {
+        if val >= 1.0 {
+            std::i32::MAX
+        } else if val <= -1.0 {
+            std::i32::MIN
+        } else {
+            let scale = (1u32 << 31) as f32;
+            (val * scale) as i32
+        }
+    }
 }
 impl FromFmt<f32> for f32 {
     fn cvt_from(val: f32) -> f32 { val }
@@ -626,7 +635,7 @@ mod test {
             let l = data[off0];
             let r = data[off1];
             assert_eq!(l, 7445);
-            assert_eq!(r, -19943);
+            assert_eq!(r, -19505);
         } else {
             panic!("wrong buffer type");
         }