support padding byte on wav encoder

include/libnyquist/Common.h

@@ -112,6 +112,12 @@ static inline uint64_t Swap64(uint64_t value)
             ((value & 0xff00000000000000LL) >> 56));
 }
 
+inline bool isOdd(const uint32_t x)
+{
+    return (x & 0x1);
+}
+
+    
 #ifdef ARCH_CPU_LITTLE_ENDIAN
     #define Read16(n) (n)
     #define Read24(n) (n)

src/WavEncoder.cpp

@@ -125,6 +125,12 @@ int WavEncoder::WriteFile(const EncoderParams p, const AudioData * d, const std:
         fout.write(reinterpret_cast<const char*>(d->samples.data()), samplesSizeInBytes);
     }
     
+    // Padding byte
+    if (isOdd(samplesSizeInBytes))
+    {
+        fout.write(reinterpret_cast<const char *>(1), 1);
+    }
+    
     // Find size
     long totalSize = fout.tellp();