diff --git a/codec/decoder/core/inc/decoder_context.h b/codec/decoder/core/inc/decoder_context.h
index fe79c9fb..347ed878 100644
--- a/codec/decoder/core/inc/decoder_context.h
+++ b/codec/decoder/core/inc/decoder_context.h
@@ -400,6 +400,8 @@ SWelsCabacCtx   pCabacCtx[WELS_CONTEXT_COUNT];
 PWelsCabacDecEngine   pCabacDecEngine;
 double dDecTime;
 SDecoderStatistics sDecoderStatistics;// For real time debugging
+int32_t iMbEcedNum;
+int32_t iMbNum;
 int32_t iECMVs[16][2];
 PPicture pECRefPic[16];
 unsigned long long uiTimeStamp;
diff --git a/codec/decoder/core/src/decoder_core.cpp b/codec/decoder/core/src/decoder_core.cpp
index 82d7d6cb..e978c2c2 100644
--- a/codec/decoder/core/src/decoder_core.cpp
+++ b/codec/decoder/core/src/decoder_core.cpp
@@ -1683,7 +1683,8 @@ static void WriteBackActiveParameters (PWelsDecoderContext pCtx) {
 int32_t ConstructAccessUnit (PWelsDecoderContext pCtx, uint8_t** ppDst, SBufferInfo* pDstInfo) {
   int32_t iErr;
   PAccessUnit pCurAu = pCtx->pAccessUnitList;
-
+  pCtx->iMbEcedNum = 0;
+  pCtx->iMbNum = 0;
   pCtx->bAuReadyFlag = false;
   pCtx->bLastHasMmco5 = false;
   bool bTmpNewSeqBegin = CheckNewSeqBeginAndUpdateActiveLayerSps (pCtx);
diff --git a/codec/decoder/core/src/error_concealment.cpp b/codec/decoder/core/src/error_concealment.cpp
index 4a867ef7..c667e107 100644
--- a/codec/decoder/core/src/error_concealment.cpp
+++ b/codec/decoder/core/src/error_concealment.cpp
@@ -82,6 +82,8 @@ void DoErrorConFrameCopy (PWelsDecoderContext pCtx) {
   uint32_t uiHeightInPixelY = (pCtx->pSps->iMbHeight) << 4;
   int32_t iStrideY = pDstPic->iLinesize[0];
   int32_t iStrideUV = pDstPic->iLinesize[1];
+  pCtx->iMbNum = pCtx->pSps->iMbWidth * pCtx->pSps->iMbHeight;
+  pCtx->iMbEcedNum = pCtx->iMbNum;
   if ((pCtx->eErrorConMethod == ERROR_CON_FRAME_COPY) && (pCtx->pCurDqLayer->sLayerInfo.sNalHeaderExt.bIdrFlag))
     pSrcPic = NULL; //no cross IDR method, should fill in data instead of copy
   if (pSrcPic == NULL) { //no ref pic, assign specific data to picture
@@ -105,10 +107,10 @@ void DoErrorConSliceCopy (PWelsDecoderContext pCtx) {
   if ((pCtx->eErrorConMethod == ERROR_CON_SLICE_COPY) && (pCtx->pCurDqLayer->sLayerInfo.sNalHeaderExt.bIdrFlag))
     pSrcPic = NULL; //no cross IDR method, should fill in data instead of copy
 
-  int32_t iMbNum = pCtx->pSps->iMbWidth * pCtx->pSps->iMbHeight;
+  pCtx->iMbNum = pCtx->pSps->iMbWidth * pCtx->pSps->iMbHeight;
   //uint8_t *pDstData[3], *pSrcData[3];
   bool* pMbCorrectlyDecodedFlag = pCtx->pCurDqLayer->pMbCorrectlyDecodedFlag;
-  int32_t iMbEcedNum = 0;
+  pCtx->iMbEcedNum = 0;
   //Do slice copy late
   int32_t iMbXyIndex;
   uint8_t* pSrcData, *pDstData;
@@ -118,7 +120,7 @@ void DoErrorConSliceCopy (PWelsDecoderContext pCtx) {
     for (int32_t iMbX = 0; iMbX < iMbWidth; ++iMbX) {
       iMbXyIndex = iMbY * iMbWidth + iMbX;
       if (!pMbCorrectlyDecodedFlag[iMbXyIndex]) {
-        iMbEcedNum++;
+        pCtx->iMbEcedNum++;
         if (pSrcPic != NULL) {
           iSrcStride = pSrcPic->iLinesize[0];
           //Y component
@@ -156,10 +158,6 @@ void DoErrorConSliceCopy (PWelsDecoderContext pCtx) {
       } //!pMbCorrectlyDecodedFlag[iMbXyIndex]
     } //iMbX
   } //iMbY
-
-  if (!pCtx->bFreezeOutput)
-    pCtx->sDecoderStatistics.uiAvgEcRatio = (pCtx->sDecoderStatistics.uiAvgEcRatio * pCtx->sDecoderStatistics.uiEcFrameNum)
-                                            + ((iMbEcedNum * 100) / iMbNum) ;
 }
 
 //Do error concealment using slice MV copy method
@@ -368,9 +366,9 @@ void DoErrorConSliceMVCopy (PWelsDecoderContext pCtx) {
   PPicture pDstPic = pCtx->pDec;
   PPicture pSrcPic = pCtx->pPreviousDecodedPictureInDpb;
 
-  int32_t iMbNum = pCtx->pSps->iMbWidth * pCtx->pSps->iMbHeight;
+  pCtx->iMbNum = pCtx->pSps->iMbWidth * pCtx->pSps->iMbHeight;
   bool* pMbCorrectlyDecodedFlag = pCtx->pCurDqLayer->pMbCorrectlyDecodedFlag;
-  int32_t iMbEcedNum = 0;
+  pCtx->iMbEcedNum = 0;
   int32_t iMbXyIndex;
   uint8_t* pDstData;
   uint32_t iDstStride = pDstPic->iLinesize[0];
@@ -395,7 +393,7 @@ void DoErrorConSliceMVCopy (PWelsDecoderContext pCtx) {
     for (int32_t iMbX = 0; iMbX < iMbWidth; ++iMbX) {
       iMbXyIndex = iMbY * iMbWidth + iMbX;
       if (!pMbCorrectlyDecodedFlag[iMbXyIndex]) {
-        iMbEcedNum++;
+        pCtx->iMbEcedNum++;
         if (pSrcPic != NULL) {
           DoMbECMvCopy (pCtx, pDstPic, pSrcPic, iMbXyIndex, iMbX, iMbY, &sMCRefMem);
         } else { //pSrcPic == NULL
@@ -422,10 +420,6 @@ void DoErrorConSliceMVCopy (PWelsDecoderContext pCtx) {
       } //!pMbCorrectlyDecodedFlag[iMbXyIndex]
     } //iMbX
   } //iMbY
-
-  if (!pCtx->bFreezeOutput)
-    pCtx->sDecoderStatistics.uiAvgEcRatio = (pCtx->sDecoderStatistics.uiAvgEcRatio * pCtx->sDecoderStatistics.uiEcFrameNum)
-                                            + ((iMbEcedNum * 100) / iMbNum) ;
 }
 
 //Mark erroneous frame as Ref Pic into DPB
diff --git a/codec/decoder/plus/src/welsDecoderExt.cpp b/codec/decoder/plus/src/welsDecoderExt.cpp
index b9c8dcba..f0320121 100644
--- a/codec/decoder/plus/src/welsDecoderExt.cpp
+++ b/codec/decoder/plus/src/welsDecoderExt.cpp
@@ -385,6 +385,8 @@ DECODING_STATE CWelsDecoder::DecodeFrame2 (const unsigned char* kpSrc,
     const int kiSrcLen,
     unsigned char** ppDst,
     SBufferInfo* pDstInfo) {
+  m_pDecContext->iMbEcedNum = 0;
+  m_pDecContext->iMbNum = 0;
   if (CheckBsBuffer (m_pDecContext, kiSrcLen)) {
     return dsOutOfMemory;
   }
@@ -464,10 +466,6 @@ DECODING_STATE CWelsDecoder::DecodeFrame2 (const unsigned char* kpSrc,
     if ((m_pDecContext->eErrorConMethod != ERROR_CON_DISABLE) && (pDstInfo->iBufferStatus == 1)) {
       //TODO after dec status updated
       m_pDecContext->iErrorCode |= dsDataErrorConcealed;
-      if (m_pDecContext->eErrorConMethod == ERROR_CON_FRAME_COPY)
-
-        m_pDecContext->sDecoderStatistics.uiAvgEcRatio = (m_pDecContext->sDecoderStatistics.uiAvgEcRatio *
-            m_pDecContext->sDecoderStatistics.uiEcFrameNum) + 100;
 
       //
       if ((m_pDecContext->sDecoderStatistics.uiWidth != (unsigned int) pDstInfo->UsrData.sSystemBuffer.iWidth)
@@ -482,6 +480,7 @@ DECODING_STATE CWelsDecoder::DecodeFrame2 (const unsigned char* kpSrc,
         ResetDecStatNums (&m_pDecContext->sDecoderStatistics);
         m_pDecContext->sDecoderStatistics.uiDecodedFrameCount++;
       }
+      m_pDecContext->sDecoderStatistics.uiAvgEcRatio = m_pDecContext->iMbEcedNum == 0 ? (m_pDecContext->sDecoderStatistics.uiAvgEcRatio * m_pDecContext->sDecoderStatistics.uiEcFrameNum) :((m_pDecContext->sDecoderStatistics.uiAvgEcRatio * m_pDecContext->sDecoderStatistics.uiEcFrameNum) + ((m_pDecContext->iMbEcedNum * 100) / m_pDecContext->iMbNum));
       m_pDecContext->sDecoderStatistics.uiEcFrameNum++;
       m_pDecContext->sDecoderStatistics.uiAvgEcRatio = m_pDecContext->sDecoderStatistics.uiAvgEcRatio /
           m_pDecContext->sDecoderStatistics.uiEcFrameNum;