From: Mike Brady <mikebrady@eircom.net>
Date: Mon, 30 Jan 2017 18:34:09 +0000 (+0000)
Subject: Add possibility of using an array of precalculated pseudo random numbers to reduce... 
X-Git-Tag: 3.0.d18~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=07641995451bb00b75794092c8e499c003d3ed8a;p=thirdparty%2Fshairport-sync.git

Add possibility of using an array of precalculated pseudo random numbers to reduce processor load.
---

diff --git a/common.c b/common.c
index d2eb17e4..cf1138a1 100644
--- a/common.c
+++ b/common.c
@@ -757,6 +757,8 @@ uint64_t ranarrayval() {
   ranarraynext = (ranarraynext++)%ranarraylength;
 }
 
+void r64arrayinit() { ranarrayinit(); }
+
 uint64_t ranarray64u() { return (ranarrayval()); }
 
 int64_t ranarray64i() { return (ranarrayval(&rx) >> 1); }
diff --git a/common.h b/common.h
index e52f82d2..e15edf1a 100644
--- a/common.h
+++ b/common.h
@@ -152,6 +152,10 @@ void r64init(uint64_t seed);
 uint64_t r64u();
 int64_t r64i();
 
+void r64arrayinit();
+uint64_t ranarray64u();
+int64_t ranarray64i();
+
 int debuglev;
 void die(char *format, ...);
 void warn(char *format, ...);
diff --git a/player.c b/player.c
index edc3dfbf..edf2f4b0 100644
--- a/player.c
+++ b/player.c
@@ -677,6 +677,8 @@ static inline void process_sample(int32_t sample, char **outp, enum sps_format_t
     }
     dither_mask -= 1;
     int64_t r = r64i();
+    // int64_t r = ranarray64i();
+    
     int64_t tpdf = (r & dither_mask) - (previous_random_number & dither_mask);
     previous_random_number = r;
     // add dither, allowing for clipping
diff --git a/shairport.c b/shairport.c
index 6106aca6..4afd8e5d 100644
--- a/shairport.c
+++ b/shairport.c
@@ -858,6 +858,10 @@ int main(int argc, char **argv) {
   // initialise random number generator
 
   r64init(0);
+  
+  // initialise the randomw number array
+  
+  r64arrayinit();
 
   /* Check if we are called with -V or --version parameter */
   if (argc >= 2 && ((strcmp(argv[1], "-V") == 0) || (strcmp(argv[1], "--version") == 0))) {