Merge branch 'upstream/alsa-source-warning-fix' into maint

1 files changed, 8 insertions, 8 deletions

diff --git a/gr-audio/lib/alsa/audio_alsa_source.cc b/gr-audio/lib/alsa/audio_alsa_source.cc
index 2f4506f71..08d4996a8 100644
--- a/gr-audio/lib/alsa/audio_alsa_source.cc
+++ b/gr-audio/lib/alsa/audio_alsa_source.cc
@@ -308,7 +308,7 @@ audio_alsa_source::work_s16 (int noutput_items,
 			     gr_vector_void_star &output_items)
 {
   typedef gr_int16	sample_t;	// the type of samples we're creating
-  static const int NBITS = 16;		// # of bits in a sample
+  static const float scale_factor = 1.0 / std::pow(2.0f, 16-1);
   
   unsigned int nchan = output_items.size ();
   float **out = (float **) &output_items[0];
@@ -329,7 +329,7 @@ audio_alsa_source::work_s16 (int noutput_items,
   bi = 0;
   for (unsigned int i = 0; i < d_period_size; i++){
     for (unsigned int chan = 0; chan < nchan; chan++){
-      out[chan][i] = (float) buf[bi++] * (1.0 / (float) ((1L << (NBITS-1)) - 1));
+      out[chan][i] = (float) buf[bi++] * scale_factor;
     }
   }
 
@@ -346,7 +346,7 @@ audio_alsa_source::work_s16_2x1 (int noutput_items,
 				 gr_vector_void_star &output_items)
 {
   typedef gr_int16	sample_t;	// the type of samples we're creating
-  static const int NBITS = 16;		// # of bits in a sample
+  static const float scale_factor = 1.0 / std::pow(2.0f, 16-1);
   
   unsigned int nchan = output_items.size ();
   float **out = (float **) &output_items[0];
@@ -370,7 +370,7 @@ audio_alsa_source::work_s16_2x1 (int noutput_items,
   for (unsigned int i = 0; i < d_period_size; i++){
     int t = (buf[bi] + buf[bi+1]) / 2;
     bi += 2;
-    out[0][i] = (float) t * (1.0 / (float) ((1L << (NBITS-1)) - 1));
+    out[0][i] = (float) t * scale_factor;
   }
 
   return d_period_size;
@@ -385,7 +385,7 @@ audio_alsa_source::work_s32 (int noutput_items,
 			     gr_vector_void_star &output_items)
 {
   typedef gr_int32	sample_t;	// the type of samples we're creating
-  static const int NBITS = 32;		// # of bits in a sample
+  static const float scale_factor = 1.0 / std::pow(2.0f, 32-1);
   
   unsigned int nchan = output_items.size ();
   float **out = (float **) &output_items[0];
@@ -406,7 +406,7 @@ audio_alsa_source::work_s32 (int noutput_items,
   bi = 0;
   for (unsigned int i = 0; i < d_period_size; i++){
     for (unsigned int chan = 0; chan < nchan; chan++){
-      out[chan][i] = (float) buf[bi++] * (1.0 / (float) ((1L << (NBITS-1)) - 1));
+      out[chan][i] = (float) buf[bi++] * scale_factor;
     }
   }
 
@@ -423,7 +423,7 @@ audio_alsa_source::work_s32_2x1 (int noutput_items,
 				 gr_vector_void_star &output_items)
 {
   typedef gr_int32	sample_t;	// the type of samples we're creating
-  static const int NBITS = 32;		// # of bits in a sample
+  static const float scale_factor = 1.0 / std::pow(2.0f, 32-1);
   
   unsigned int nchan = output_items.size ();
   float **out = (float **) &output_items[0];
@@ -447,7 +447,7 @@ audio_alsa_source::work_s32_2x1 (int noutput_items,
   for (unsigned int i = 0; i < d_period_size; i++){
     int t = (buf[bi] + buf[bi+1]) / 2;
     bi += 2;
-    out[0][i] = (float) t * (1.0 / (float) ((1L << (NBITS-1)) - 1));
+    out[0][i] = (float) t * scale_factor;
   }
 
   return d_period_size;