[x265] [PATCH] Fix lowpassdct negative shift operator

[Pavan Tarun Chakka Venkata]

>From 465d64623a692f73f0bb87d3b14b07eba0d97c37 Mon Sep 17 00:00:00 2001
From: Pavan Tarun <pavan.tarun at multicorewareinc.com>
Date: Tue, 13 Aug 2024 15:27:44 +0530
Subject: [PATCH] Fix lowpassdct negative shift operator

---
 source/common/lowpassdct.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/source/common/lowpassdct.cpp b/source/common/lowpassdct.cpp
index 0dc10a6aa..b1c75bc7c 100644
--- a/source/common/lowpassdct.cpp
+++ b/source/common/lowpassdct.cpp
@@ -58,7 +58,7 @@ static void lowPassDct8_c(const int16_t* src, int16_t*
dst, intptr_t srcStride)
     }

     // replace first coef with total block average
-    dst[0] = totalSum >> (-1 + (X265_DEPTH - 8));
+    dst[0] = (X265_DEPTH == 8) ? (totalSum << 1) : (totalSum >>
((X265_DEPTH - 9)));
 }

 static void lowPassDct16_c(const int16_t* src, int16_t* dst, intptr_t
srcStride)
@@ -83,7 +83,7 @@ static void lowPassDct16_c(const int16_t* src, int16_t*
dst, intptr_t srcStride)
     {
         memcpy(&dst[i * 16], &coef[i * 8], 8 * sizeof(int16_t));
     }
-    dst[0] = static_cast<int16_t>(totalSum >> (1 + (X265_DEPTH - 8)));
+    dst[0] = static_cast<int16_t>(totalSum >> (1 + (X265_DEPTH - 8)));
 }

 static void lowPassDct32_c(const int16_t* src, int16_t* dst, intptr_t
srcStride)
@@ -108,7 +108,7 @@ static void lowPassDct32_c(const int16_t* src, int16_t*
dst, intptr_t srcStride)
     {
         memcpy(&dst[i * 32], &coef[i * 16], 16 * sizeof(int16_t));
     }
-    dst[0] = static_cast<int16_t>(totalSum >> (3 + (X265_DEPTH - 8)));
+    dst[0] = static_cast<int16_t>(totalSum >> (3 + (X265_DEPTH - 8)));
 }

 namespace X265_NS {
-- 
2.46.0
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