diff --git a/src/codec/SkHeifCodec.cpp b/src/codec/SkHeifCodec.cpp
index 008c129..1067511 100644
--- a/src/codec/SkHeifCodec.cpp
+++ b/src/codec/SkHeifCodec.cpp
@@ -279,6 +279,7 @@
         return kInvalidInput;
     }
 
+    fSwizzler.reset(nullptr);
     this->allocateStorage(dstInfo);
 
     int rows = this->readRows(dstInfo, dst, dstRowBytes, dstInfo.height(), options);
@@ -355,6 +356,12 @@
         return kInvalidInput;
     }
 
+    if (options.fSubset) {
+        this->initializeSwizzler(dstInfo, options);
+    } else {
+        fSwizzler.reset(nullptr);
+    }
+
     this->allocateStorage(dstInfo);
 
     return kSuccess;