Use more efficient float->int conversion in SFOutputStream.

Signed-off-by: Stefan Westerfeld <stefan@space.twc.de>

src/rawconverter.cc

@@ -104,24 +104,6 @@ make_endian_shift ()
     }
 }
 
-template<int BITS>
-static int
-float_to_int_clip (float f)
-{
-  const int64_t inorm = (1LL << (BITS - 1));
-  const float min_value = -inorm;
-  const float max_value =  inorm - 1;
-  const float norm      =  inorm;
-  const float snorm     = f * norm;
-
-  if (snorm >= max_value)
-    return inorm - 1;
-  else if (snorm <= min_value)
-    return -inorm;
-  else
-    return snorm;
-}
-
 template<int BIT_DEPTH, RawFormat::Endian ENDIAN, RawFormat::Encoding ENCODING>
 void
 RawConverterImpl<BIT_DEPTH, ENDIAN, ENCODING>::to_raw (const float *samples, unsigned char *output_bytes, size_t n_samples)

src/rawconverter.hh

@@ -31,4 +31,22 @@ public:
   virtual void from_raw (const unsigned char *bytes, float *samples, size_t n_samples) = 0;
 };
 
+template<int BITS>
+static inline int
+float_to_int_clip (float f)
+{
+  const int64_t inorm = (1LL << (BITS - 1));
+  const float min_value = -inorm;
+  const float max_value =  inorm - 1;
+  const float norm      =  inorm;
+  const float snorm     = f * norm;
+
+  if (snorm >= max_value)
+    return inorm - 1;
+  else if (snorm <= min_value)
+    return -inorm;
+  else
+    return snorm;
+}
+
 #endif /* AUDIOWMARK_RAW_CONVERTER_HH */

src/sfoutputstream.cc

@@ -16,6 +16,7 @@
  */
 
 #include "sfoutputstream.hh"
+#include "rawconverter.hh"
 #include "utils.hh"
 
 #include <math.h>
@@ -103,13 +104,7 @@ SFOutputStream::write_frames (const vector<float>& samples)
 {
   vector<int> isamples (samples.size());
   for (size_t i = 0; i < samples.size(); i++)
-    {
-      const double norm      =  0x80000000LL;
-      const double min_value = -0x80000000LL;
-      const double max_value =  0x7FFFFFFF;
-
-      isamples[i] = lrint (bound<double> (min_value, samples[i] * norm, max_value));
-    }
+    isamples[i] = float_to_int_clip<32> (samples[i]);
 
   sf_count_t frames = samples.size() / m_n_channels;
   sf_count_t count = sf_writef_int (m_sndfile, isamples.data(), frames);

src/sfoutputstream.hh

@@ -51,7 +51,7 @@ public:
 
   Error  open (const std::string& filename, int n_channels, int sample_rate, int bit_depth, OutFormat out_format = OutFormat::WAV);
   Error  open (std::vector<unsigned char> *data, int n_channels, int sample_rate, int bit_depth, OutFormat out_format = OutFormat::WAV);
-  Error  write_frames (const std::vector<float>& frames) override;
+  Error  write_frames (const std::vector<float>& frames) override AUDIOWMARK_EXTRA_OPT;
   Error  close() override;
   int    bit_depth() const override;
   int    sample_rate() const override;