From ffcae2dd71731f3502e241af4dd47207bcf7bfaa Mon Sep 17 00:00:00 2001
From: "Christian W. Zuckschwerdt" <christian@zuckschwerdt.org>
Date: Wed, 7 Jul 2021 11:30:15 +0200
Subject: [PATCH] Fix scaling in CS16-CS8 conversion

---
 client/ClientStreamData.cpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/client/ClientStreamData.cpp b/client/ClientStreamData.cpp
index 4cb6c62..0fd443a 100644
--- a/client/ClientStreamData.cpp
+++ b/client/ClientStreamData.cpp
@@ -104,13 +104,15 @@ void ClientStreamData::convertRecvBuffs(void * const *buffs, const size_t numEle
     case CONVERT_CS16_CS8:
     ///////////////////////////
     {
+        // note that we expect CS8 scaleFactor to be power of 2, usually 128
+        const int scale = 32768/int(scaleFactor);
         for (size_t i = 0; i < recvBuffs.size(); i++)
         {
             auto in = (int8_t *)recvBuffs[i];
             auto out = (int16_t *)buffs[i];
             for (size_t j = 0; j < numElems*2; j++)
             {
-                out[j] = int16_t(in[j]);
+                out[j] = int16_t(in[j])*scale;
             }
         }
     }
@@ -236,13 +238,15 @@ void ClientStreamData::convertSendBuffs(const void * const *buffs, const size_t
     case CONVERT_CS16_CS8:
     ///////////////////////////
     {
+        // note that we expect CS16 scaleFactor to be a power of 2, usually 2048
+        const int scale = int(scaleFactor + 1)/128; // round e.g. 2047.0 and 32767.0
         for (size_t i = 0; i < sendBuffs.size(); i++)
         {
             auto in = (int16_t *)buffs[i];
             auto out = (int8_t *)sendBuffs[i];
             for (size_t j = 0; j < numElems*2; j++)
             {
-                out[j] = int8_t(in[j]);
+                out[j] = int8_t(in[j]/scale);
             }
         }
     }