diff --git a/media/codec2/sfplugin/CCodec.cpp b/media/codec2/sfplugin/CCodec.cpp
index 10a6896..d5fb9e3 100644
--- a/media/codec2/sfplugin/CCodec.cpp
+++ b/media/codec2/sfplugin/CCodec.cpp
@@ -1400,6 +1400,10 @@
             }
         }
 
+        if (config->mTunneled) {
+            config->mOutputFormat->setInt32("android._tunneled", 1);
+        }
+
         ALOGD("setup formats input: %s",
                 config->mInputFormat->debugString().c_str());
         ALOGD("setup formats output: %s",
diff --git a/media/codec2/sfplugin/CCodecBufferChannel.cpp b/media/codec2/sfplugin/CCodecBufferChannel.cpp
index cdd9275..ba3c9ca 100644
--- a/media/codec2/sfplugin/CCodecBufferChannel.cpp
+++ b/media/codec2/sfplugin/CCodecBufferChannel.cpp
@@ -1358,6 +1358,12 @@
                 }
             }
         }
+
+        int32_t tunneled = 0;
+        if (!outputFormat->findInt32("android._tunneled", &tunneled)) {
+            tunneled = 0;
+        }
+        mTunneled = (tunneled != 0);
     }
 
     // Set up pipeline control. This has to be done after mInputBuffers and
@@ -1853,10 +1859,21 @@
         }
     }
 
+    bool drop = false;
+    if (worklet->output.flags & C2FrameData::FLAG_DROP_FRAME) {
+        ALOGV("[%s] onWorkDone: drop buffer but keep metadata", mName);
+        drop = true;
+    }
+
     if (notifyClient && !buffer && !flags) {
-        ALOGV("[%s] onWorkDone: Not reporting output buffer (%lld)",
-              mName, work->input.ordinal.frameIndex.peekull());
-        notifyClient = false;
+        if (mTunneled && drop && outputFormat) {
+            ALOGV("[%s] onWorkDone: Keep tunneled, drop frame with format change (%lld)",
+                  mName, work->input.ordinal.frameIndex.peekull());
+        } else {
+            ALOGV("[%s] onWorkDone: Not reporting output buffer (%lld)",
+                  mName, work->input.ordinal.frameIndex.peekull());
+            notifyClient = false;
+        }
     }
 
     if (buffer) {
diff --git a/media/codec2/sfplugin/CCodecBufferChannel.h b/media/codec2/sfplugin/CCodecBufferChannel.h
index 5a2aca2..d2862bd 100644
--- a/media/codec2/sfplugin/CCodecBufferChannel.h
+++ b/media/codec2/sfplugin/CCodecBufferChannel.h
@@ -323,6 +323,8 @@
         return mCrypto != nullptr || mDescrambler != nullptr;
     }
     std::atomic_bool mSendEncryptedInfoBuffer;
+
+    std::atomic_bool mTunneled;
 };
 
 // Conversion of a c2_status_t value to a status_t value may depend on the