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 f1079257b78da801d03d4b3fcf74f23d0640bb41..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 }
@@ -181,6 +190,28 @@ impl<'a, T:Copy+IntoFmt<i32>+IntoFmt<f32>> SampleReader for GenericSampleReader<
     }
 }
 
+struct S8SampleReader<'a> {
+    data:   &'a [u8],
+    stride: usize,
+}
+
+impl<'a> SampleReader for S8SampleReader<'a> {
+    fn get_samples_i32(&self, pos: usize, dst: &mut Vec<i32>) {
+        let mut off = pos;
+        for el in dst.iter_mut() {
+            *el = (self.data[off] ^ 0x80).cvt_into();
+            off += self.stride;
+        }
+    }
+    fn get_samples_f32(&self, pos: usize, dst: &mut Vec<f32>) {
+        let mut off = pos;
+        for el in dst.iter_mut() {
+            *el = (self.data[off] ^ 0x80).cvt_into();
+            off += self.stride;
+        }
+    }
+}
+
 struct PackedSampleReader<'a> {
     data:   &'a [u8],
     fmt:    NASoniton,
@@ -200,7 +231,7 @@ impl<'a> PackedSampleReader<'a> {
             let src = &self.data[offset..];
             *el = if !self.fmt.float {
                     match (self.bpp, self.fmt.be) {
-                        (1, _)     => src[0].cvt_into(),
+                        (1, _)     => if !self.fmt.signed { src[0].cvt_into() } else { (src[0] ^ 0x80).cvt_into() },
                         (2, true)  => (read_u16be(src).unwrap() as i16).cvt_into(),
                         (2, false) => (read_u16le(src).unwrap() as i16).cvt_into(),
                         (3, true)  => ((read_u24be(src).unwrap() << 8) as i32).cvt_into(),
@@ -280,6 +311,9 @@ impl<'a> PackedSampleWriter<'a> {
                 match (self.bpp, self.fmt.be) {
                     (1, _) => {
                         dst[0] = u8::cvt_from(*el);
+                        if self.fmt.signed {
+                            dst[0] ^= 0x80;
+                        }
                     },
                     (2, true)  => write_u16be(dst, i16::cvt_from(*el) as u16).unwrap(),
                     (2, false) => write_u16le(dst, i16::cvt_from(*el) as u16).unwrap(),
@@ -374,7 +408,11 @@ Result<NABufferType, SoundConvertError> {
             NABufferType::AudioU8(ref ab) => {
                 let stride = ab.get_stride();
                 let data = ab.get_data();
-                Box::new(GenericSampleReader { data, stride })
+                if !src_fmt.signed {
+                    Box::new(GenericSampleReader { data, stride })
+                } else {
+                    Box::new(S8SampleReader { data, stride })
+                }
             },
             NABufferType::AudioI16(ref ab) => {
                 let data = ab.get_data();
@@ -597,7 +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");
         }