ref: e8d045ad53c0d2041e3b45f52251661b048ef1d4
dir: /codec/processing/src/backgrounddetection/BackgroundDetection.cpp/
/*!
* \copy
* Copyright (c) 2013, Cisco Systems
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*/
#include "BackgroundDetection.h"
WELSVP_NAMESPACE_BEGIN
#define LOG2_BGD_OU_SIZE (4)
#define LOG2_BGD_OU_SIZE_UV (LOG2_BGD_OU_SIZE-1)
#define BGD_OU_SIZE (1<<LOG2_BGD_OU_SIZE)
#define BGD_OU_SIZE_UV (BGD_OU_SIZE>>1)
#define BGD_THD_SAD (2*BGD_OU_SIZE*BGD_OU_SIZE)
#define BGD_THD_ASD_UV (4*BGD_OU_SIZE_UV)
#define LOG2_MB_SIZE (4)
#define OU_SIZE_IN_MB (BGD_OU_SIZE >> 4)
#define Q_FACTOR (8)
#define BGD_DELTA_QP_THD (3)
#define OU_LEFT (0x01)
#define OU_RIGHT (0x02)
#define OU_TOP (0x04)
#define OU_BOTTOM (0x08)
CBackgroundDetection::CBackgroundDetection (int32_t iCpuFlag) {
m_eMethod = METHOD_BACKGROUND_DETECTION;
WelsMemset (&m_BgdParam, 0, sizeof (m_BgdParam));
m_iLargestFrameSize = 0;
}
CBackgroundDetection::~CBackgroundDetection() {
WelsFree (m_BgdParam.pOU_array);
}
EResult CBackgroundDetection::Process (int32_t iType, SPixMap* pSrcPixMap, SPixMap* pRefPixMap) {
EResult eReturn = RET_INVALIDPARAM;
if (pSrcPixMap == NULL || pRefPixMap == NULL)
return eReturn;
m_BgdParam.pCur[0] = (uint8_t*)pSrcPixMap->pPixel[0];
m_BgdParam.pCur[1] = (uint8_t*)pSrcPixMap->pPixel[1];
m_BgdParam.pCur[2] = (uint8_t*)pSrcPixMap->pPixel[2];
m_BgdParam.pRef[0] = (uint8_t*)pRefPixMap->pPixel[0];
m_BgdParam.pRef[1] = (uint8_t*)pRefPixMap->pPixel[1];
m_BgdParam.pRef[2] = (uint8_t*)pRefPixMap->pPixel[2];
m_BgdParam.iBgdWidth = pSrcPixMap->sRect.iRectWidth;
m_BgdParam.iBgdHeight = pSrcPixMap->sRect.iRectHeight;
m_BgdParam.iStride[0] = pSrcPixMap->iStride[0];
m_BgdParam.iStride[1] = pSrcPixMap->iStride[1];
m_BgdParam.iStride[2] = pSrcPixMap->iStride[2];
int32_t iCurFrameSize = m_BgdParam.iBgdWidth * m_BgdParam.iBgdHeight;
if (m_BgdParam.pOU_array == NULL || iCurFrameSize > m_iLargestFrameSize) {
WelsFree (m_BgdParam.pOU_array);
m_BgdParam.pOU_array = AllocateOUArrayMemory (m_BgdParam.iBgdWidth, m_BgdParam.iBgdHeight);
m_iLargestFrameSize = iCurFrameSize;
}
if (m_BgdParam.pOU_array == NULL)
return eReturn;
BackgroundDetection (&m_BgdParam);
return RET_SUCCESS;
}
EResult CBackgroundDetection::Set (int32_t iType, void* pParam) {
if (pParam == NULL) {
return RET_INVALIDPARAM;
}
SBGDInterface* pInterface = (SBGDInterface*)pParam;
m_BgdParam.pBackgroundMbFlag = (int8_t*)pInterface->pBackgroundMbFlag;
m_BgdParam.pCalcRes = pInterface->pCalcRes;
return RET_SUCCESS;
}
inline SBackgroundOU* CBackgroundDetection::AllocateOUArrayMemory (int32_t iWidth, int32_t iHeight) {
int32_t iMaxOUWidth = (BGD_OU_SIZE - 1 + iWidth) >> LOG2_BGD_OU_SIZE;
int32_t iMaxOUHeight = (BGD_OU_SIZE - 1 + iHeight) >> LOG2_BGD_OU_SIZE;
return (SBackgroundOU*)WelsMalloc (iMaxOUWidth * iMaxOUHeight * sizeof (SBackgroundOU));
}
void CBackgroundDetection::GetOUParameters (SVAACalcResult* sVaaCalcInfo, int32_t iMbIndex, int32_t iMbWidth,
SBackgroundOU* pBgdOU) {
int32_t iSubSD[4];
uint8_t iSubMAD[4];
int32_t iSubSAD[4];
uint8_t (*pMad8x8)[4];
int32_t (*pSad8x8)[4];
int32_t (*pSd8x8)[4];
pSad8x8 = sVaaCalcInfo->pSad8x8;
pMad8x8 = sVaaCalcInfo->pMad8x8;
pSd8x8 = sVaaCalcInfo->pSumOfDiff8x8;
iSubSAD[0] = pSad8x8[iMbIndex][0];
iSubSAD[1] = pSad8x8[iMbIndex][1];
iSubSAD[2] = pSad8x8[iMbIndex][2];
iSubSAD[3] = pSad8x8[iMbIndex][3];
iSubSD[0] = pSd8x8[iMbIndex][0];
iSubSD[1] = pSd8x8[iMbIndex][1];
iSubSD[2] = pSd8x8[iMbIndex][2];
iSubSD[3] = pSd8x8[iMbIndex][3];
iSubMAD[0] = pMad8x8[iMbIndex][0];
iSubMAD[1] = pMad8x8[iMbIndex][1];
iSubMAD[2] = pMad8x8[iMbIndex][2];
iSubMAD[3] = pMad8x8[iMbIndex][3];
pBgdOU->iSD = iSubSD[0] + iSubSD[1] + iSubSD[2] + iSubSD[3];
pBgdOU->iSAD = iSubSAD[0] + iSubSAD[1] + iSubSAD[2] + iSubSAD[3];
pBgdOU->iSD = WELS_ABS (pBgdOU->iSD);
// get the max absolute difference (MAD) of OU and min value of the MAD of sub-blocks of OU
pBgdOU->iMAD = WELS_MAX (WELS_MAX (iSubMAD[0], iSubMAD[1]), WELS_MAX (iSubMAD[2], iSubMAD[3]));
pBgdOU->iMinSubMad = WELS_MIN (WELS_MIN (iSubMAD[0], iSubMAD[1]), WELS_MIN (iSubMAD[2], iSubMAD[3]));
// get difference between the max and min SD of the SDs of sub-blocks of OU
pBgdOU->iMaxDiffSubSd = WELS_MAX (WELS_MAX (iSubSD[0], iSubSD[1]), WELS_MAX (iSubSD[2], iSubSD[3])) -
WELS_MIN (WELS_MIN (iSubSD[0], iSubSD[1]), WELS_MIN (iSubSD[2], iSubSD[3]));
}
void CBackgroundDetection::ForegroundBackgroundDivision (vBGDParam* pBgdParam) {
int32_t iPicWidthInOU = pBgdParam->iBgdWidth >> LOG2_BGD_OU_SIZE;
int32_t iPicHeightInOU = pBgdParam->iBgdHeight >> LOG2_BGD_OU_SIZE;
int32_t iPicWidthInMb = (15 + pBgdParam->iBgdWidth) >> 4;
SBackgroundOU* pBackgroundOU = pBgdParam->pOU_array;
for (int32_t j = 0; j < iPicHeightInOU; j ++) {
for (int32_t i = 0; i < iPicWidthInOU; i++) {
GetOUParameters (pBgdParam->pCalcRes, (j * iPicWidthInMb + i) << (LOG2_BGD_OU_SIZE - LOG2_MB_SIZE), iPicWidthInMb,
pBackgroundOU);
pBackgroundOU->iBackgroundFlag = 0;
if (pBackgroundOU->iMAD > 63) {
pBackgroundOU++;
continue;
}
if ((pBackgroundOU->iMaxDiffSubSd <= pBackgroundOU->iSAD >> 3
|| pBackgroundOU->iMaxDiffSubSd <= (BGD_OU_SIZE * Q_FACTOR))
&& pBackgroundOU->iSAD < (BGD_THD_SAD << 1)) { //BGD_OU_SIZE*BGD_OU_SIZE>>2
if (pBackgroundOU->iSAD <= BGD_OU_SIZE * Q_FACTOR) {
pBackgroundOU->iBackgroundFlag = 1;
} else {
pBackgroundOU->iBackgroundFlag = pBackgroundOU->iSAD < BGD_THD_SAD ?
(pBackgroundOU->iSD < (pBackgroundOU->iSAD * 3) >> 2) :
(pBackgroundOU->iSD << 1 < pBackgroundOU->iSAD);
}
}
pBackgroundOU++;
}
}
}
inline int32_t CBackgroundDetection::CalculateAsdChromaEdge (uint8_t* pOriRef, uint8_t* pOriCur, int32_t iStride) {
int32_t ASD = 0;
int32_t idx;
for (idx = 0; idx < BGD_OU_SIZE_UV; idx++) {
ASD += *pOriCur - *pOriRef;
pOriRef += iStride;
pOriCur += iStride;
}
return WELS_ABS (ASD);
}
inline bool CBackgroundDetection::ForegroundDilation23Luma (SBackgroundOU* pBackgroundOU,
SBackgroundOU* pOUNeighbours[]) {
SBackgroundOU* pOU_L = pOUNeighbours[0];
SBackgroundOU* pOU_R = pOUNeighbours[1];
SBackgroundOU* pOU_U = pOUNeighbours[2];
SBackgroundOU* pOU_D = pOUNeighbours[3];
if (pBackgroundOU->iMAD > pBackgroundOU->iMinSubMad << 1) {
int32_t iMaxNbrForegroundMad;
int32_t iMaxNbrBackgroundMad;
int32_t aBackgroundMad[4];
int32_t aForegroundMad[4];
aForegroundMad[0] = (pOU_L->iBackgroundFlag - 1) & pOU_L->iMAD;
aForegroundMad[1] = (pOU_R->iBackgroundFlag - 1) & pOU_R->iMAD;
aForegroundMad[2] = (pOU_U->iBackgroundFlag - 1) & pOU_U->iMAD;
aForegroundMad[3] = (pOU_D->iBackgroundFlag - 1) & pOU_D->iMAD;
iMaxNbrForegroundMad = WELS_MAX (WELS_MAX (aForegroundMad[0], aForegroundMad[1]), WELS_MAX (aForegroundMad[2],
aForegroundMad[3]));
aBackgroundMad[0] = ((!pOU_L->iBackgroundFlag) - 1) & pOU_L->iMAD;
aBackgroundMad[1] = ((!pOU_R->iBackgroundFlag) - 1) & pOU_R->iMAD;
aBackgroundMad[2] = ((!pOU_U->iBackgroundFlag) - 1) & pOU_U->iMAD;
aBackgroundMad[3] = ((!pOU_D->iBackgroundFlag) - 1) & pOU_D->iMAD;
iMaxNbrBackgroundMad = WELS_MAX (WELS_MAX (aBackgroundMad[0], aBackgroundMad[1]), WELS_MAX (aBackgroundMad[2],
aBackgroundMad[3]));
return ((iMaxNbrForegroundMad > pBackgroundOU->iMinSubMad << 2) || (pBackgroundOU->iMAD > iMaxNbrBackgroundMad << 1
&& pBackgroundOU->iMAD <= (iMaxNbrForegroundMad * 3) >> 1));
}
return 0;
}
inline bool CBackgroundDetection::ForegroundDilation23Chroma (int8_t iNeighbourForegroundFlags,
int32_t iStartSamplePos, int32_t iPicStrideUV, vBGDParam* pBgdParam) {
static const int8_t kaOUPos[4] = {OU_LEFT, OU_RIGHT, OU_TOP, OU_BOTTOM};
int32_t aEdgeOffset[4] = {0, BGD_OU_SIZE_UV - 1, 0, iPicStrideUV* (BGD_OU_SIZE_UV - 1)};
int32_t iStride[4] = {iPicStrideUV, iPicStrideUV, 1, 1};
// V component first, high probability because V stands for red color and human skin colors have more weight on this component
for (int32_t i = 0; i < 4; i++) {
if (iNeighbourForegroundFlags & kaOUPos[i]) {
uint8_t* pRefC = pBgdParam->pRef[2] + iStartSamplePos + aEdgeOffset[i];
uint8_t* pCurC = pBgdParam->pCur[2] + iStartSamplePos + aEdgeOffset[i];
if (CalculateAsdChromaEdge (pRefC, pCurC, iStride[i]) > BGD_THD_ASD_UV) {
return 1;
}
}
}
// U component, which stands for blue color, low probability
for (int32_t i = 0; i < 4; i++) {
if (iNeighbourForegroundFlags & kaOUPos[i]) {
uint8_t* pRefC = pBgdParam->pRef[1] + iStartSamplePos + aEdgeOffset[i];
uint8_t* pCurC = pBgdParam->pCur[1] + iStartSamplePos + aEdgeOffset[i];
if (CalculateAsdChromaEdge (pRefC, pCurC, iStride[i]) > BGD_THD_ASD_UV) {
return 1;
}
}
}
return 0;
}
inline void CBackgroundDetection::ForegroundDilation (SBackgroundOU* pBackgroundOU, SBackgroundOU* pOUNeighbours[],
vBGDParam* pBgdParam, int32_t iChromaSampleStartPos) {
int32_t iPicStrideUV = pBgdParam->iStride[1];
int32_t iSumNeighBackgroundFlags = pOUNeighbours[0]->iBackgroundFlag + pOUNeighbours[1]->iBackgroundFlag +
pOUNeighbours[2]->iBackgroundFlag + pOUNeighbours[3]->iBackgroundFlag;
if (pBackgroundOU->iSAD > BGD_OU_SIZE * Q_FACTOR) {
switch (iSumNeighBackgroundFlags) {
case 0:
case 1:
pBackgroundOU->iBackgroundFlag = 0;
break;
case 2:
case 3:
pBackgroundOU->iBackgroundFlag = !ForegroundDilation23Luma (pBackgroundOU, pOUNeighbours);
// chroma component check
if (pBackgroundOU->iBackgroundFlag == 1) {
int8_t iNeighbourForegroundFlags = (!pOUNeighbours[0]->iBackgroundFlag) | ((!pOUNeighbours[1]->iBackgroundFlag) << 1)
| ((!pOUNeighbours[2]->iBackgroundFlag) << 2) | ((!pOUNeighbours[3]->iBackgroundFlag) << 3);
pBackgroundOU->iBackgroundFlag = !ForegroundDilation23Chroma (iNeighbourForegroundFlags, iChromaSampleStartPos,
iPicStrideUV, pBgdParam);
}
break;
default:
break;
}
}
}
inline void CBackgroundDetection::BackgroundErosion (SBackgroundOU* pBackgroundOU, SBackgroundOU* pOUNeighbours[]) {
if (pBackgroundOU->iMaxDiffSubSd <= (BGD_OU_SIZE * Q_FACTOR)) { //BGD_OU_SIZE*BGD_OU_SIZE>>2
int32_t iSumNeighBackgroundFlags = pOUNeighbours[0]->iBackgroundFlag + pOUNeighbours[1]->iBackgroundFlag +
pOUNeighbours[2]->iBackgroundFlag + pOUNeighbours[3]->iBackgroundFlag;
int32_t sumNbrBGsad = (pOUNeighbours[0]->iSAD & (-pOUNeighbours[0]->iBackgroundFlag)) + (pOUNeighbours[2]->iSAD &
(-pOUNeighbours[2]->iBackgroundFlag))
+ (pOUNeighbours[1]->iSAD & (-pOUNeighbours[1]->iBackgroundFlag)) + (pOUNeighbours[3]->iSAD &
(-pOUNeighbours[3]->iBackgroundFlag));
if (pBackgroundOU->iSAD * iSumNeighBackgroundFlags <= (3 * sumNbrBGsad) >> 1) {
if (iSumNeighBackgroundFlags == 4) {
pBackgroundOU->iBackgroundFlag = 1;
} else {
if ((pOUNeighbours[0]->iBackgroundFlag & pOUNeighbours[1]->iBackgroundFlag)
|| (pOUNeighbours[2]->iBackgroundFlag & pOUNeighbours[3]->iBackgroundFlag)) {
pBackgroundOU->iBackgroundFlag = !ForegroundDilation23Luma (pBackgroundOU, pOUNeighbours);
}
}
}
}
}
inline void CBackgroundDetection::SetBackgroundMbFlag (int8_t* pBackgroundMbFlag, int32_t iPicWidthInMb,
int32_t iBackgroundMbFlag) {
*pBackgroundMbFlag = iBackgroundMbFlag;
}
inline void CBackgroundDetection::UpperOUForegroundCheck (SBackgroundOU* pCurOU, int8_t* pBackgroundMbFlag,
int32_t iPicWidthInOU, int32_t iPicWidthInMb) {
if (pCurOU->iSAD > BGD_OU_SIZE * Q_FACTOR) {
SBackgroundOU* pOU_L = pCurOU - 1;
SBackgroundOU* pOU_R = pCurOU + 1;
SBackgroundOU* pOU_U = pCurOU - iPicWidthInOU;
SBackgroundOU* pOU_D = pCurOU + iPicWidthInOU;
if (pOU_L->iBackgroundFlag + pOU_R->iBackgroundFlag + pOU_U->iBackgroundFlag + pOU_D->iBackgroundFlag <= 1) {
SetBackgroundMbFlag (pBackgroundMbFlag, iPicWidthInMb, 0);
pCurOU->iBackgroundFlag = 0;
}
}
}
void CBackgroundDetection::ForegroundDilationAndBackgroundErosion (vBGDParam* pBgdParam) {
int32_t iPicStrideUV = pBgdParam->iStride[1];
int32_t iPicWidthInOU = pBgdParam->iBgdWidth >> LOG2_BGD_OU_SIZE;
int32_t iPicHeightInOU = pBgdParam->iBgdHeight >> LOG2_BGD_OU_SIZE;
int32_t iOUStrideUV = iPicStrideUV << (LOG2_BGD_OU_SIZE - 1);
int32_t iPicWidthInMb = (15 + pBgdParam->iBgdWidth) >> 4;
SBackgroundOU* pBackgroundOU = pBgdParam->pOU_array;
int8_t* pVaaBackgroundMbFlag = (int8_t*)pBgdParam->pBackgroundMbFlag;
SBackgroundOU* pOUNeighbours[4];//0: left; 1: right; 2: top; 3: bottom
pOUNeighbours[2] = pBackgroundOU;//top OU
for (int32_t j = 0; j < iPicHeightInOU; j ++) {
int8_t* pRowSkipFlag = pVaaBackgroundMbFlag;
pOUNeighbours[0] = pBackgroundOU;//left OU
pOUNeighbours[3] = pBackgroundOU + (iPicWidthInOU & ((j == iPicHeightInOU - 1) - 1)); //bottom OU
for (int32_t i = 0; i < iPicWidthInOU; i++) {
pOUNeighbours[1] = pBackgroundOU + (i < iPicWidthInOU - 1); //right OU
if (pBackgroundOU->iBackgroundFlag)
ForegroundDilation (pBackgroundOU, pOUNeighbours, pBgdParam, j * iOUStrideUV + (i << LOG2_BGD_OU_SIZE_UV));
else
BackgroundErosion (pBackgroundOU, pOUNeighbours);
// check the up OU
if (j > 1 && i > 0 && i < iPicWidthInOU - 1 && pOUNeighbours[2]->iBackgroundFlag == 1) {
UpperOUForegroundCheck (pOUNeighbours[2], pRowSkipFlag - OU_SIZE_IN_MB * iPicWidthInMb, iPicWidthInOU, iPicWidthInMb);
}
SetBackgroundMbFlag (pRowSkipFlag, iPicWidthInMb, pBackgroundOU->iBackgroundFlag);
// preparation for the next OU
pRowSkipFlag += OU_SIZE_IN_MB;
pOUNeighbours[0] = pBackgroundOU;
pOUNeighbours[2]++;
pOUNeighbours[3]++;
pBackgroundOU++;
}
pOUNeighbours[2] = pBackgroundOU - iPicWidthInOU;
pVaaBackgroundMbFlag += OU_SIZE_IN_MB * iPicWidthInMb;
}
}
void CBackgroundDetection::BackgroundDetection (vBGDParam* pBgdParam) {
// 1st step: foreground/background coarse division
ForegroundBackgroundDivision (pBgdParam);
// 2nd step: foreground dilation and background erosion
ForegroundDilationAndBackgroundErosion (pBgdParam);
}
WELSVP_NAMESPACE_END