Fix HEVC streams requiring a higher bitrate to enable high quality surround audio

src/Connection.c

@@ -19,6 +19,7 @@ AUDIO_RENDERER_CALLBACKS AudioCallbacks;
 int NegotiatedVideoFormat;
 volatile int ConnectionInterrupted;
 int HighQualitySurroundEnabled;
+int OriginalVideoBitrate;
 
 // Connection stages
 static const char* stageNames[STAGE_MAX] = {
@@ -223,6 +224,7 @@ int LiStartConnection(PSERVER_INFORMATION serverInfo, PSTREAM_CONFIGURATION stre
 
     NegotiatedVideoFormat = 0;
     memcpy(&StreamConfig, streamConfig, sizeof(StreamConfig));
+    OriginalVideoBitrate = streamConfig->bitrate;
     RemoteAddrString = strdup(serverInfo->address);
     
     // FEC only works in 16 byte chunks, so we must round down

src/Limelight-internal.h

@@ -21,6 +21,7 @@ extern AUDIO_RENDERER_CALLBACKS AudioCallbacks;
 extern int NegotiatedVideoFormat;
 extern volatile int ConnectionInterrupted;
 extern int HighQualitySurroundEnabled;
+extern int OriginalVideoBitrate;
 
 #ifndef UINT24_MAX
 #define UINT24_MAX 0xFFFFFF

src/SdpGenerator.c

@@ -362,7 +362,8 @@ static PSDP_OPTION getAttributesList(char*urlSafeAddr) {
         }
 
         if (AppVersionQuad[0] >= 7) {
-            if (StreamConfig.bitrate > HIGH_BITRATE_THRESHOLD && audioChannelCount > 2) {
+            // Decide to use HQ audio based on the original video bitrate, not the HEVC-adjusted value
+            if (OriginalVideoBitrate >= HIGH_BITRATE_THRESHOLD && audioChannelCount > 2) {
                 // Enable high quality mode for surround sound
                 err |= addAttributeString(&optionHead, "x-nv-audio.surround.AudioQuality", "1");