xref: /utopia/UTPA2-700.0.x/modules/mfe/drv/mfe_ex/cModel/msRateCtrl.c (revision 53ee8cc121a030b8d368113ac3e966b4705770ef)

//<MStar Software>
//******************************************************************************
// MStar Software
// Copyright (c) 2010 - 2012 MStar Semiconductor, Inc. All rights reserved.
// All software, firmware and related documentation herein ("MStar Software") are
// intellectual property of MStar Semiconductor, Inc. ("MStar") and protected by
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//    modification/derivatives thereof is transferred to you under Terms.
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// 2. You understand that MStar Software might include, incorporate or be
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//******************************************************************************
//<MStar Software>
//////////////////////////////////////////////////////////////////////////
// MStar simple rate control
//////////////////////////////////////////////////////////////////////////

#include "MFE_chip.h"
#include "mfe_type.h"
#include "mfe_common.h"
#include "ms_dprintf.h"

#include "mdrv_mfe_math.h"

#include "msRateCtrl.h"
#if defined(_MFE_T8_)&&defined(_MIPS_PLATFORM_)&&!defined(_KERNEL_MODE_)
#include <stdlib.h>
#include <stdio.h>
#endif



// H264
    // Spec limitation is [1, 51]
	#define MSRC_MAX_QP_H264        48UL
	#define MSRC_MIN_QP_H264        12UL
	#define FRAMESKIP_THR_QP_H264   40UL
// MPEG-4, H263
    // Spec limitation is [1, 31]
	#define MSRC_MAX_QP_MPEG4        28UL
	#define MSRC_MIN_QP_MPEG4        1UL
	#define FRAMESKIP_THR_QP_MPEG4   20UL

//! How many seconds of frames are responsible for compensation of bitrate usage.
#define CBR_DEPUTY_SECOND     1UL
#define CVBR_DEPUTY_SECOND    3UL
#define VBR_DEPUTY_SECOND     10UL

#define MIN_DEPUTY_FACTOR     10UL

//! Default I-frame weighting over inter-frame
// #define IFRAME_WEIGHT   2UL
// #define PFRAME_WEIGHT   1UL
#define IFRAME_WEIGHT   8UL
#define PFRAME_WEIGHT   4UL
#define BFRAME_WEIGHT	3UL



#ifdef _SUPPORT_MBLEVEL_RC_
	#define MBACT_NORMALIZATION_FACTOR 2UL
	//#define FLAT_AREA_VAR_THR          5UL
	#define SPEC_QP_DIFF_LIMIT         2UL // Spec limitation
	#define USE_INT_PREC
	// Below are used when USE_INT_PREC
	#define SCALE_BITS                 6UL
	#define SCALE_ACT                  6UL
#endif

//////////////////////////////////////////////////////////////////////////
// global variables
//////////////////////////////////////////////////////////////////////////
#if 0//ndef _USE_EXT_RCDATA_
	CVBRRateControl g_cvbrContext;
	CVBRRCInfo g_cvbrInfo;
	MS_S32 g_cvbrFrameSkip;
#endif

//private:
MS_S32 cvbr_ComputeFrameQStep(CVBRRateControl* ct, MS_S32 nFrameType);	// Return the target 'QStep'
MS_S32 cvbr_ComputeMbQP(CVBRRateControl* ct, MS_S32 mb_idx);	// Return the target 'QP'

MS_S32 rcQP2Qstep(CVBRRateControl* ct, MS_S32 QP);
MS_S32 rcQstep2QP(CVBRRateControl* ct, MS_S32 QstepX32);

/*
void output_MBR_reg(void* hd, CVBRRateControl* ct)
{
    if (ct->m_nVPMbRow>0 && ct->m_nVPSize<=0)
        sd_output(hd, 0, 2, "reg_mfe_g_er_mode");
    else if (ct->m_nVPMbRow<=0 && ct->m_nVPSize>0)
        sd_output(hd, 1, 2, "reg_mfe_g_er_mode");
    else if (ct->m_nVPMbRow>0 && ct->m_nVPSize>0)
        sd_output(hd, 2, 2, "reg_mfe_g_er_mode");
    else
        sd_output(hd, 3, 2, "reg_mfe_g_er_mode");
    if (ct->m_nVPMbRow==1)
        sd_output(hd, 0, 2, "reg_mfe_g_er_mby");
    else if (ct->m_nVPMbRow==2)
        sd_output(hd, 1, 2, "reg_mfe_g_er_mby");
    else if (ct->m_nVPMbRow==4)
        sd_output(hd, 2, 2, "reg_mfe_g_er_mby");
    else if (ct->m_nVPMbRow==8)
        sd_output(hd, 3, 2, "reg_mfe_g_er_mby");
    else
        sd_output(hd, 0, 2, "reg_mfe_g_er_mby");
}
*/

void cvbr_InitRateControl(CVBRRateControl* ct, CVBRRCInfo* pRCInfo)
{
	MS_S32 i, j;

	ct->m_nFrameCount = 0;

	MS_ASSERT(pRCInfo->nWidth<=MAX_MB_WIDTH*16);
	if (pRCInfo->rcMethod==CONST_QUALITY)
		MS_ASSERT(pRCInfo->rcGranularity==FRAMELEVELRC);
	// Copy parameters, no error checking yet.
	ct->m_nCodecType = pRCInfo->nCodecType;
	ct->m_nWidth = pRCInfo->nWidth;
	ct->m_nHeight = pRCInfo->nHeight;
/*
	if (pRCInfo->fTargetFrameRate - (MS_S32)pRCInfo->fTargetFrameRate != 0) {
		switch ((MS_S32)pRCInfo->fTargetFrameRate) {
		case 14:	// 14.985
			ct->m_nTargetFrameRateNum = 15000;
			ct->m_nTargetFrameRateDeNum = 1001;
			break;
		case 23:	// 23.976
			ct->m_nTargetFrameRateNum = 24000;
			ct->m_nTargetFrameRateDeNum = 1001;
			break;
		case 29:	// 29.97
			ct->m_nTargetFrameRateNum = 30000;
			ct->m_nTargetFrameRateDeNum = 1001;
			break;
		default:
			MS_ASSERT(0);
		}
	}
*/
	//2010/01/21 because LG GP3 no support MS_FLOAT operation, so only support 29.97 now.
	//if fps is 29.97, fTargetFrameRate_is_float =1
	if (pRCInfo->fTargetFrameRate_is_float==1) {
			ct->m_nTargetFrameRateNum = 30000;
			ct->m_nTargetFrameRateDeNum = 1001;
	}
	else {
		ct->m_nTargetFrameRateNum = pRCInfo->int_fTargetFrameRate;
		ct->m_nTargetFrameRateDeNum = 1;
	}

	ct->m_nTargetFrameRateInt = ct->m_nTargetFrameRateNum / ct->m_nTargetFrameRateDeNum;
	ct->m_nBitrate = pRCInfo->nBitrate;
	ct->m_nMaxBitrate = pRCInfo->nMaxBitrate;
	ct->m_nConstQP = pRCInfo->nConstQP;
	ct->m_nVPSize = pRCInfo->nVPSize;
	ct->m_nVPMbRow = pRCInfo->nVPMbRow;
	ct->m_bFixedFrameRate = pRCInfo->bFixedFrameRate;
	ct->m_nPCount = pRCInfo->nPCount;
	ct->m_nBCount = pRCInfo->nBCount;
	ct->m_rcGranularity = pRCInfo->rcGranularity;
	ct->m_rcMethod = pRCInfo->rcMethod;
	// More bitrate checking
	if (ct->m_rcMethod==CONSTRAINED_VARIABLE_BITRATE) {
		if (ct->m_nBitrate==0)
			ct->m_nBitrate = (MS_S32)(ct->m_nMaxBitrate *6/10);
		if (ct->m_nMaxBitrate==0)
			ct->m_nMaxBitrate = (MS_S32)(ct->m_nBitrate * 14/10);
	ct->m_nMaxOffset = (MS_S32)MFE_DIV_S64((MS_S64)(ct->m_nMaxBitrate - ct->m_nBitrate)*ct->m_nTargetFrameRateDeNum, ct->m_nTargetFrameRateNum) ;
//	ct->m_nMaxOffset = (MS_S32)((MS_S64)(ct->m_nMaxBitrate - ct->m_nBitrate)*ct->m_nTargetFrameRateDeNum / ct->m_nTargetFrameRateNum);

		if (ct->m_rcGranularity==FRAMELEVELRC)
			ct->m_nMaxOffset = (ct->m_nMaxOffset) >> 2;
	}
	else {
		ct->m_nMaxBitrate = 0;  // Don't care
	}

	// Derived
	ct->m_nAvgBitsPerFrame = (MS_S32)MFE_DIV_S64((MS_S64)ct->m_nBitrate*ct->m_nTargetFrameRateDeNum, ct->m_nTargetFrameRateNum) ;
	//ct->m_nAvgBitsPerFrame = (MS_S32)((MS_S64)ct->m_nBitrate *ct->m_nTargetFrameRateDeNum / ct->m_nTargetFrameRateNum);

    if (ct->m_nPCount == -1) {
        // infinite P, no B
        // lim((1 + m_nPCount) / (IFRAME_WEIGHT + PFRAME_WEIGHT * m_nPCount)) = 1 / 4
        i = 1;
        j = 4;
    }
    else {
        i = 1+ct->m_nPCount*(1+ct->m_nBCount);
        j = IFRAME_WEIGHT + PFRAME_WEIGHT*ct->m_nPCount + BFRAME_WEIGHT*(ct->m_nPCount*ct->m_nBCount);
    }

    ct->m_nBitsPerFrame[0] = (MS_S32)MFE_DIV_S64((MS_S64)ct->m_nBitrate*ct->m_nTargetFrameRateDeNum*IFRAME_WEIGHT*i, (MS_S64)j*ct->m_nTargetFrameRateNum);
    ct->m_nBitsPerFrame[1] = (MS_S32)MFE_DIV_S64((MS_S64)ct->m_nBitrate*ct->m_nTargetFrameRateDeNum*PFRAME_WEIGHT*i, (MS_S64)j*ct->m_nTargetFrameRateNum);
    ct->m_nBitsPerFrame[2] = (MS_S32)MFE_DIV_S64((MS_S64)ct->m_nBitrate*ct->m_nTargetFrameRateDeNum*BFRAME_WEIGHT*i, (MS_S64)j*ct->m_nTargetFrameRateNum);
#ifdef _SUPPORT_MBLEVEL_RC_
	ct->m_nMbWidth = (ct->m_nWidth+15)>>4;
#endif

	// QP, QStep: min, max
	if (ct->m_nCodecType==REG_ENC_MODE_MPG4 || ct->m_nCodecType==REG_ENC_MODE_H263) {
		ct->m_nMinQP = MSRC_MIN_QP_MPEG4;
		ct->m_nMaxQP = MSRC_MAX_QP_MPEG4;
		ct->m_nMinQStep = rcQP2Qstep(ct, MSRC_MIN_QP_MPEG4)-1;
		ct->m_nMaxQStep = rcQP2Qstep(ct, MSRC_MAX_QP_MPEG4);
		ct->m_nFrameSkipThrQP = FRAMESKIP_THR_QP_MPEG4;
	}
	else {
		ct->m_nMinQP = MSRC_MIN_QP_H264;
		ct->m_nMaxQP = MSRC_MAX_QP_H264;
		ct->m_nMinQStep = rcQP2Qstep(ct, MSRC_MIN_QP_H264)-1;
		ct->m_nMaxQStep = rcQP2Qstep(ct, MSRC_MAX_QP_H264);
		ct->m_nFrameSkipThrQP = FRAMESKIP_THR_QP_H264;
		MS_ASSERT(ct->m_nCodecType==REG_ENC_MODE_H264);
	}

	// Bitrate usage monitoring
	ct->m_nMinDeputyCount = (ct->m_nTargetFrameRateNum*CBR_DEPUTY_SECOND)/ct->m_nTargetFrameRateDeNum;
	ct->m_nTargetFullness = ct->m_nBitrate >> 1;
	ct->m_nBufFullness = ct->m_nTargetFullness;
	switch (ct->m_rcMethod) {
		case VARIABLE_BITRATE:
			ct->m_nDeputyCount = (ct->m_nTargetFrameRateNum*VBR_DEPUTY_SECOND)/ct->m_nTargetFrameRateDeNum;
			break;
		case CONSTRAINED_VARIABLE_BITRATE:
			ct->m_BitrateGauge = MfeDrvMemMalloc(ct->m_nTargetFrameRateInt * sizeof(MS_S32), (const MS_S8*)("m_BitrateGauge"));
			if (ct->m_BitrateGauge) {
				memset(ct->m_BitrateGauge, 0, ct->m_nTargetFrameRateInt * sizeof(MS_S32));

				ct->m_BitrateGauge[0] = ct->m_nBitsPerFrame[0];
				for (i = 1; i < ct->m_nTargetFrameRateInt; i++) {
					ct->m_BitrateGauge[i] = ct->m_nBitsPerFrame[1];
					for (j = 0; j < ct->m_nBCount; j++, i++) {
						if (i == ct->m_nTargetFrameRateInt)
							break;
						ct->m_BitrateGauge[i] = ct->m_nBitsPerFrame[2];
					}
				}
			}
			ct->m_nDeputyCount = (ct->m_nTargetFrameRateNum*CVBR_DEPUTY_SECOND)/ct->m_nTargetFrameRateDeNum;
			ct->m_nGaugeCount = ct->m_nTargetFrameRateInt;
			ct->m_nGaugeIndex = 0;
			ct->m_nGaugeBitrate = (MS_S32)MFE_DIV_S64((MS_S64)ct->m_nBitrate*ct->m_nTargetFrameRateDeNum*ct->m_nGaugeCount, ct->m_nTargetFrameRateNum) ;
			//ct->m_nGaugeBitrate = (MS_S32)((MS_S64)ct->m_nBitrate*ct->m_nTargetFrameRateDeNum*ct->m_nGaugeCount) / ct->m_nTargetFrameRateNum;
			break;
		case CONST_BITRATE:
		default:
	ct->m_nDeputyCount = (MS_S32)MFE_DIV_S64((MS_S64)ct->m_nTargetFrameRateNum*CBR_DEPUTY_SECOND,ct->m_nTargetFrameRateDeNum) ;
	//ct->m_nDeputyCount = (MS_S32)((MS_S64)ct->m_nTargetFrameRateNum*CBR_DEPUTY_SECOND)/ct->m_nTargetFrameRateDeNum;
			break;
	}

	ct->m_nFrameCount = 0;
	ct->m_nTotalBits = 0;
	ct->m_nLastFrameAvgQStep[0] = ct->m_nLastFrameAvgQStep[1] = ct->m_nLastFrameBits = 0;
	ct->m_nLongTermQP64 = 0;

	ct->m_nTotalMB = (ct->m_nWidth>>4)*(ct->m_nHeight>>4);
#if 0//ndef _USE_EXT_RCDATA_
	g_cvbrFrameSkip = 0;
#endif


//	ms_dprintk(DRV_L3,"[CVBRRC] InitRateControl: w=%d, h=%d, FPS=%2.3f, FixedFPS=%d, Bitrate=%d\n",
//		ct->m_nWidth, ct->m_nHeight, (MS_FLOAT)ct->m_nTargetFrameRateNum/ct->m_nTargetFrameRateDeNum,
//		ct->m_bFixedFrameRate, ct->m_nBitrate);




}


void cvbr_CloseRateControl(CVBRRateControl* ct)
{
    if (ct->m_rcMethod == CONSTRAINED_VARIABLE_BITRATE) {
        if (ct->m_BitrateGauge) {
            MfeDrvMemFree((void**)&ct->m_BitrateGauge, (const MS_S8*)("m_BitrateGauge"));
            ct->m_BitrateGauge = NULL;
        }
    }
}

// FieldType: 0--Progressive, 1--First field, 2--second field.
MS_S32 cvbr_InitFrame(CVBRRateControl* ct, MS_S32 nFrameType, MS_S8 FieldType)
{
	MS_S32 nDeputyCount = 0;
	MS_S32 delta = 0, nRtnQP;

	if (FieldType==0||FieldType==1)
		ct->m_bIsBotField = 0;
	else
		ct->m_bIsBotField = 1;	// FieldType is 2

	ct->m_nFrameType = nFrameType;
	ct->m_nLastVPBits = 0;
	ct->m_nNewPacket = 0;

	// Target frame bitcount
	if (FieldType!=2)
	{
		if (ct->m_nFrameCount>0) {
			// 1. Determine the number of future frame to compensate for current bitrate mismatch.
			if (ct->m_nFrameCount>ct->m_nDeputyCount*MIN_DEPUTY_FACTOR)
				nDeputyCount = ct->m_nDeputyCount;
			else if (ct->m_nFrameCount<ct->m_nMinDeputyCount)
				nDeputyCount = ct->m_nMinDeputyCount;
			else
				nDeputyCount = ct->m_nMinDeputyCount +
				(ct->m_nFrameCount-ct->m_nMinDeputyCount)*(ct->m_nDeputyCount-ct->m_nMinDeputyCount)/(ct->m_nDeputyCount*MIN_DEPUTY_FACTOR-ct->m_nMinDeputyCount);
			// 2. Calculate the bitcount that this frame should be compensate for.
			if (ct->m_rcMethod==CONST_BITRATE) {
			delta = (MS_S32)MFE_DIV_S64((MS_S64)(ct->m_nBufFullness-ct->m_nTargetFullness)*ct->m_nTargetFrameRateDeNum, ct->m_nTargetFrameRateNum) ;
		       //delta = (MS_S32)((MS_S64)(ct->m_nBufFullness-ct->m_nTargetFullness)*ct->m_nTargetFrameRateDeNum)/ct->m_nTargetFrameRateNum;


// 			delta = (ct->m_nBufFullness>ct->m_nTargetFullness) ?
// 				(MS_S32)((ct->m_nBufFullness-ct->m_nTargetFullness)/ct->m_fTargetFrameRate) : ct->m_nBufFullness-ct->m_nTargetFullness;
			}
			else if (ct->m_rcMethod==CONSTRAINED_VARIABLE_BITRATE) {
				delta = (ct->m_nBufFullness-ct->m_nTargetFullness) / nDeputyCount;
				if (delta<-ct->m_nMaxOffset)
					delta = -ct->m_nMaxOffset;
			}
			else if (ct->m_rcMethod==VARIABLE_BITRATE) {
				delta = (ct->m_nBufFullness-ct->m_nTargetFullness) / nDeputyCount;
				if (delta>0 && ((ct->m_nLastFrameAvgQStep[0]<<6)>ct->m_nLongTermQP64))
					delta = delta>>1;  // Make it more variable bitrate to allow better quality
			}
			// 3. Finally, calculate the target bitcount.
			if (ct->m_nPCount==0) {
				ct->m_nTargetBits = ct->m_nBitsPerFrame[0] - delta;
			}
			else {
				switch (nFrameType) {
			case I_VOP:
				ct->m_nTargetBits = ct->m_nBitsPerFrame[0] - delta;
				break;
			case P_VOP:
				ct->m_nTargetBits = ct->m_nBitsPerFrame[1] - delta;
				break;
			case B_VOP:
				ct->m_nTargetBits = ct->m_nBitsPerFrame[2] - delta;
				break;
				}
			}
			if (ct->m_nTargetBits<=(ct->m_nAvgBitsPerFrame>>3))
				ct->m_nTargetBits = (ct->m_nAvgBitsPerFrame>>3);  // Target bitcount must>0 for ComputeFrameQP()
		}
		else {
			ct->m_nTargetBits = ct->m_nBitsPerFrame[0];    // Must be I-frame
		}

		/* Return initial frame QP */

		ct->m_nFrameQStep = cvbr_ComputeFrameQStep(ct, nFrameType);

		ct->m_nLastFrameAvgQStep[0] = ct->m_nLastFrameAvgQStep[1] = 0;
		ct->m_nLastFrameBits = 0;

#ifdef _SUPPORT_MBLEVEL_RC_
		ct->m_nTargetMbBits = ct->m_nTargetBits / ct->m_nTotalMB;
#endif
	}
	else {	// bottom field
		MS_S32 nTargetBits;
		ct->m_nFrameQStep = ct->m_nLastFrameAvgQStep[0] / ((ct->m_nTotalMB>>1)-1);
#ifdef _SUPPORT_MBLEVEL_RC_
		nTargetBits = ct->m_nTargetBits - ct->m_nLastFrameBits;
		if (nTargetBits<ct->m_nTargetBits>>3)
			nTargetBits = ct->m_nTargetBits>>3;
		ct->m_nTargetMbBits = nTargetBits / (ct->m_nTotalMB>>1);
#endif
	}

#ifdef _SUPPORT_MBLEVEL_RC_
	ct->m_nMBN = 0;
	if (ct->m_nTargetMbBits<1)
		ct->m_nTargetMbBits = 1;
#endif

	nRtnQP = rcQstep2QP(ct, ct->m_nFrameQStep);
	//ct->m_nFrameQStep = rcQP2Qstep(ct, nRtnQP);

//	ms_dprintk(DRV_L3,"[CVBRRC] %5d%s[%s] InitFrame: TargetBits %7d InitQP %2d Buffer %7d Deputy=%d\n",
//		ct->m_nFrameCount, FieldType==0?"F":(FieldType==1?"T":"B"), nFrameType==I_VOP?"I":(nFrameType==P_VOP?"P":"B"),
//		(MS_S32)(ct->m_nTargetBits), nRtnQP, ct->m_nBufFullness, nDeputyCount);

	return nRtnQP;
}

MS_S32 cvbr_UpdateFrame(CVBRRateControl* ct, MS_S32 totalUsedBits, MS_S8 bDummyFrame, MS_S8 FieldType)
{
	MS_S32 frameskip = 0;

	// Update counter
	ct->m_nTotalBits += totalUsedBits;
	ct->m_nLastFrameBits += totalUsedBits;
       if(ct->m_nBufFullness < MAX_BUF_FULL)
	  ct->m_nBufFullness += totalUsedBits;
	if (FieldType!=1) {
		ct->m_nFrameCount++;
		ct->m_nLastTargetBits = ct->m_nTargetBits;

		if (!bDummyFrame) {
			ct->m_nLastFrameAvgQStep[0] = (ct->m_nLastFrameAvgQStep[0]+ct->m_nLastFrameAvgQStep[1]) / (FieldType==0 ? ct->m_nTotalMB-1 : ct->m_nTotalMB-2);
			// Variable bitrate
			if (ct->m_rcMethod==VARIABLE_BITRATE)
				ct->m_nLongTermQP64 += ((ct->m_nLastFrameAvgQStep[0]<<6)-ct->m_nLongTermQP64) / ct->m_nFrameCount;
			else if (ct->m_rcMethod==CONSTRAINED_VARIABLE_BITRATE) {
				if (ct->m_nFrameCount==1)
					ct->m_nLongTermQP64 = ct->m_nLastFrameAvgQStep[0]<<6;
				else
					ct->m_nLongTermQP64 = (ct->m_nLongTermQP64*(ct->m_nDeputyCount-1) + (ct->m_nLastFrameAvgQStep[0]<<6)) / ct->m_nDeputyCount;
			}
		}
		else {
			ct->m_nLastFrameAvgQStep[0] = ct->m_nFrameQStep;
		}

		if (ct->m_rcMethod==CONSTRAINED_VARIABLE_BITRATE) {
			ct->m_nGaugeBitrate -= ct->m_BitrateGauge[ct->m_nGaugeIndex];
			ct->m_nGaugeBitrate += totalUsedBits;
			ct->m_BitrateGauge[ct->m_nGaugeIndex] = totalUsedBits;
			ct->m_nGaugeIndex++;
			if (ct->m_nGaugeIndex==ct->m_nGaugeCount)
				ct->m_nGaugeIndex = 0;
		}

		// Update buffer status
		ct->m_nBufFullness -= ct->m_nAvgBitsPerFrame;
	}


	// Check if next skipped frame(s) needed
	if (FieldType!=1 && !ct->m_bFixedFrameRate && !bDummyFrame)
	{
		if (ct->m_rcMethod==CONSTRAINED_VARIABLE_BITRATE || ct->m_rcMethod==VARIABLE_BITRATE) {
			if (   ct->m_nLongTermQP64>(rcQP2Qstep(ct, ct->m_nFrameSkipThrQP)<<6)
				&& ct->m_nLastFrameBits >= (ct->m_nLastTargetBits<<1) ) {
					//frameskip = (ct->m_nLastFrameBits / ct->m_nLastTargetBits)-1;
					frameskip = (MS_S32)((ct->m_nLastFrameBits - ct->m_nLastTargetBits) / ct->m_nAvgBitsPerFrame - 1);
					if (frameskip<0)
						frameskip = 0;
					else if (frameskip>ct->m_nMaxFrozenFrame)
						frameskip = ct->m_nMaxFrozenFrame;
			}
		}
		else if (ct->m_rcMethod==CONST_BITRATE) {
			if (ct->m_nLastFrameAvgQStep[0]>rcQP2Qstep(ct, ct->m_nFrameSkipThrQP)) {
				// Actual fullness is updated after encoding dummy-P frame
				MS_S32 nBufFullness = ct->m_nBufFullness;
				while (nBufFullness > ct->m_nTargetFullness) {
					nBufFullness = (MS_S32)(nBufFullness - ct->m_nAvgBitsPerFrame);
					frameskip += 1;
				}
			}
		}
	}
/*
#ifdef DEBUG
	if (frameskip > 255)
	{
		fprintf (stderr, "Warning: frameskip > 255\n");
	}
	if (FieldType!=1){
	    MS_S64 tmp_bitrate ;
	    tmp_bitrate= (MS_S32)MFE_DIV_S64((MS_S64)ct->m_nTotalBits*ct->m_nTargetFrameRateNum, ct->m_nFrameCount*ct->m_nTargetFrameRateDeNum) ;

//	    ms_dprintk(DRV_L3,"[CVBRRC] UpdateFrame(%7d bits, %3d%%) AvgQ=%2d LTQ=%2d Bitrate=%8d frameskip=%2d\n",
//		ct->m_nLastFrameBits, (ct->m_nLastFrameBits-ct->m_nTargetBits)*100/ct->m_nTargetBits, rcQstep2QP(ct, ct->m_nLastFrameAvgQStep[0]),
//		(MS_S32)(ct->m_nLongTermQP64+32)>>6,(MS_S32)tmp_bitrate, frameskip);
	}

//	DEBUG_RC(("[CVBRRC]       UpdateFrame(%7d bits, %3d%%) AvgQ=%2d LTQ=%2d Bitrate=%8d frameskip=%2d\n",
//	totalUsedBits, (totalUsedBits-ct->m_nTargetBits)*100/ct->m_nTargetBits, ct->m_nLastFrameAvgQStep[0],
//	(MS_S32)ct->m_fLongTermQP, ct->m_nGaugeBitrate, frameskip));
#endif
*/
	return frameskip;
}

#define SMOOTH_PERIOD	1UL
#define INIT_QP_FACTOR	720UL
#define MIN_INIT_QP		1UL
#define MAX_INIT_QP		15UL

/* Return target QPStep */
MS_S32 cvbr_ComputeFrameQStep(CVBRRateControl* ct, MS_S32 nFrameType)
{
	MS_S32 newQPStep=0;
	MS_S64 buf_rest;
	MS_S32 buf_rest_pic;
	MS_S32 frames_left;
	MS_S32 nAdjust;

	MS_S32 bitrate = ct->m_nBitrate;
	MS_S32 targetFPS_DeNum =  ct->m_nTargetFrameRateDeNum;
	MS_S32 targetFPS_Num =  ct->m_nTargetFrameRateNum;
	MS_S32 TotalMB = ct->m_nTotalMB;
	MS_S32 frame_count = ct->m_nFrameCount;

	// For the very first frame, guess one qp!
	if (ct->m_nFrameCount==0) {
		MS_S32 nbpMb, newQP;
		if (ct->m_rcMethod==CONST_QUALITY) {
			newQP = ct->m_nConstQP;
			newQPStep = rcQP2Qstep(ct, newQP);	// So that frame qp will be exactly ct->m_nConstQP
		}
		else {
	              nbpMb= (MS_S32)MFE_DIV_S64((MS_S64)bitrate*targetFPS_DeNum, TotalMB*targetFPS_Num) +1 ;
	          //nbpMb = (MS_S32)((MS_S64)ct->m_nBitrate*ct->m_nTargetFrameRateDeNum)/(ct->m_nTotalMB*ct->m_nTargetFrameRateNum) + 1;
			newQP = INIT_QP_FACTOR / nbpMb;
			if (newQP<MIN_INIT_QP)
				newQP = MIN_INIT_QP;
			else if (newQP>MAX_INIT_QP)
				newQP = MAX_INIT_QP;
			newQPStep = newQP<<QS_SHIFT_FACTOR;
		}

		ct->m_nMaxFrozenFrame = newQP>>1;
		if (ct->m_nMaxFrozenFrame>15)
			ct->m_nMaxFrozenFrame=15;
		return newQPStep;
	}

	if (ct->m_rcMethod==CONST_QUALITY)
		return rcQP2Qstep(ct, ct->m_nConstQP);

	if (ct->m_rcMethod==CONST_BITRATE) {
	       buf_rest= MFE_DIV_S64((MS_S64)frame_count*targetFPS_DeNum*bitrate, targetFPS_Num) ;
          //buf_rest = (((MS_S64)ct->m_nFrameCount*ct->m_nTargetFrameRateDeNum*ct->m_nBitrate)/ct->m_nTargetFrameRateNum);

		buf_rest += (SMOOTH_PERIOD*ct->m_nBitrate) - ct->m_nTotalBits;

		newQPStep = ct->m_nLastFrameAvgQStep[0];
		frames_left = (SMOOTH_PERIOD * ct->m_nTargetFrameRateNum) / ct->m_nTargetFrameRateDeNum;
		//if (frames_left > 0)
		{
			MS_S32 dQP;
			buf_rest_pic = (MS_S32)MFE_DIV_S64(buf_rest , frames_left);
			dQP = ct->m_nLastFrameAvgQStep[0]>>3;
			if (ct->m_nLastFrameBits > (buf_rest_pic*9)>>3) {
				newQPStep = ct->m_nLastFrameAvgQStep[0]+dQP;
			}
			else if (ct->m_nLastFrameBits < (buf_rest_pic*7)>>3) {
				newQPStep = ct->m_nLastFrameAvgQStep[0]-dQP;
			}
		}
	}

	else if (ct->m_rcMethod==CONSTRAINED_VARIABLE_BITRATE) {
 		MS_S32 nLowBound, nHighBound;
		nAdjust = ct->m_nLongTermQP64>>2;
		nLowBound = (ct->m_nLongTermQP64 - nAdjust) >> 6;
		nHighBound = (ct->m_nLongTermQP64 + nAdjust) >> 6;
		if (ct->m_nPCount>0 && nFrameType==I_VOP) {
			newQPStep = ct->m_nLastFrameAvgQStep[0];
			if (ct->m_nGaugeBitrate<ct->m_nBitrate)
				newQPStep = newQPStep-(1<<QS_SHIFT_FACTOR);
			newQPStep = MSRC_MAX((1<<QS_SHIFT_FACTOR), newQPStep);
			newQPStep = MSRC_MIN((12<<QS_SHIFT_FACTOR), newQPStep);
		}
		else {
			MS_S64 tmp;
	              tmp= MFE_DIV_S64((MS_S64)ct->m_nLongTermQP64 * MFE_DIV_S64(ct->m_nTotalBits,ct->m_nFrameCount), ct->m_nTargetBits) ;
                 //tmp = ct->m_nLongTermQP64 * (ct->m_nTotalBits/ct->m_nFrameCount) /ct->m_nTargetBits);
			MS_ASSERT((tmp >> 6) < (((MS_S64)1)<<31));
	              newQPStep=  (MS_S32)(
				  	MFE_DIV_S64((MS_S64)ct->m_nLongTermQP64 * MFE_DIV_S64(ct->m_nTotalBits,ct->m_nFrameCount),
				  	             ct->m_nTargetBits)  >>6) ;
	//newQPStep = (MS_S32)((ct->m_nLongTermQP64 * (ct->m_nTotalBits/ct->m_nFrameCount) / ct->m_nTargetBits) >> 6);
			if (ct->m_nLastFrameBits>ct->m_nLastTargetBits) {
				nAdjust = ((ct->m_nLastFrameBits-ct->m_nLastTargetBits)/ct->m_nMaxOffset) + (1<<QS_SHIFT_FACTOR);
				if (nAdjust>(3<<QS_SHIFT_FACTOR)) nAdjust=(3<<QS_SHIFT_FACTOR);
				if ((ct->m_nLastFrameAvgQStep[0]<<6) > ct->m_nLongTermQP64) {  // Danger! Make it more aggressive
					nHighBound = ct->m_nLastFrameAvgQStep[0]+nAdjust;
					newQPStep = ct->m_nLastFrameAvgQStep[0]+nAdjust;
				}
				else {
					nHighBound += nAdjust;
					newQPStep += nAdjust;
				}
			}
			else if (ct->m_nGaugeBitrate>ct->m_nBitrate) {
				if (newQPStep < ct->m_nLastFrameAvgQStep[0])
					newQPStep = ct->m_nLastFrameAvgQStep[0];
				if ((newQPStep<<6) < ct->m_nLongTermQP64)
					newQPStep = ct->m_nLongTermQP64>>6;
			}
			else {
				if ((newQPStep<<6) >= ct->m_nLongTermQP64)
					newQPStep = (ct->m_nLongTermQP64>>6)-1;
				if (ct->m_nTargetFullness>ct->m_nBufFullness) {
					nAdjust = (ct->m_nTargetFullness-ct->m_nBufFullness) / (MS_S32)ct->m_nBitrate;
					newQPStep -= nAdjust;
				}
			}
		}
		newQPStep = MSRC_MIN(nHighBound, newQPStep);
		newQPStep = MSRC_MAX(nLowBound, newQPStep);
	}
	else if (ct->m_rcMethod==VARIABLE_BITRATE) {
		MS_S32 nLowBound, nHighBound;
		if (ct->m_nPCount>0 && nFrameType==I_VOP) {
			newQPStep = ct->m_nLastFrameAvgQStep[0];
			if ((ct->m_nLastFrameAvgQStep[0]<<6) > ct->m_nLongTermQP64)
				newQPStep = newQPStep-(1<<QS_SHIFT_FACTOR);
		}
		else {
			MS_S32 nAdjLTQ;
			MS_S64 tmp;
			if (ct->m_nFrameCount>=ct->m_nTargetFrameRateInt || ct->m_nPCount==0) {
	              tmp=  MFE_DIV_S64(
				  	(MS_S64)ct->m_nLongTermQP64 * MFE_DIV_S64(ct->m_nTotalBits,ct->m_nFrameCount),
				  	ct->m_nAvgBitsPerFrame) ;
                 //tmp = ct->m_nLongTermQP64 * (ct->m_nTotalBits/ct->m_nFrameCount) / ct->m_nAvgBitsPerFrame;
				MS_ASSERT((tmp >> 6) < (((MS_S64)1)<<31));

	              nAdjLTQ=  (MS_S32)(MFE_DIV_S64(
				  	(MS_S64)ct->m_nLongTermQP64 * MFE_DIV_S64(ct->m_nTotalBits,ct->m_nFrameCount),
				  	ct->m_nAvgBitsPerFrame)   >>6) ;
	//nAdjLTQ = (MS_S32)((ct->m_nLongTermQP64 * (ct->m_nTotalBits/ct->m_nFrameCount) / ct->m_nAvgBitsPerFrame) >> 6);

			}
			else {
				nAdjLTQ = ct->m_nLongTermQP64>>6;   // Wait for stabilization
			}
			MS_ASSERT(ct->m_nTargetBits>0);
			newQPStep = (nAdjLTQ * ct->m_nAvgBitsPerFrame) / ct->m_nTargetBits;

			nAdjust = MSRC_MAX((2<<QS_SHIFT_FACTOR), (MS_S32)(nAdjLTQ)>>2);
			nLowBound = (MS_S32)(nAdjLTQ) - nAdjust;
			nHighBound = (MS_S32)(nAdjLTQ) + nAdjust;
			if (ct->m_nLastFrameBits>ct->m_nLastTargetBits) {
				nAdjust = (MS_S32)(ct->m_nLastFrameBits/ct->m_nLastTargetBits);
				if (nAdjust>2) nAdjust=2;
				nHighBound += nAdjust;
			}

			if (ct->m_nAvgBitsPerFrame>ct->m_nTargetBits) {
				newQPStep = MSRC_MIN(nHighBound, newQPStep);
			}
			else {
				newQPStep = MSRC_MAX(nLowBound, newQPStep);
			}
		}
	}

	return newQPStep;
}

// MS_S32 QP2QSTEP32[52] = {	// QP2Qstep(QP) * 32
// 	20,
// 	22, 26, 28, 32, 36, 40, 44, 52, 56, 64,
// 	72, 80, 88, 104, 112, 128, 144, 160, 176, 208,
// 	224, 256, 288, 320, 352, 416, 448, 512, 576, 640,
// 	704, 832, 896, 1024, 1152, 1280, 1408, 1664, 1792, 2048,
// 	2304, 2560, 2816, 3328, 3584, 4096, 4608, 5120, 5632, 6656,
// 	7168,
// };
MS_S32 rcQP2Qstep(CVBRRateControl* ct,  MS_S32 QP)
{
    if (ct->m_nCodecType==REG_ENC_MODE_H264)
    {
        MS_S32 i;
        MS_S32 Qstep;
        static const MS_S32 QP2QSTEP[6] = { 20, 22, 26, 28, 32, 36 };

        Qstep = QP2QSTEP[QP % 6];
        for( i=0; i<(QP/6); i++)
            Qstep *= 2;

        return Qstep;
    }
    else
    {
        return QP<<QS_SHIFT_FACTOR;
    }

    return 0;   // Should never entering this.
}

MS_S32 rcQstep2QP(CVBRRateControl* ct, MS_S32 QstepX32)
{
    if (ct->m_nCodecType==REG_ENC_MODE_H264)
    {
        MS_S32 q_per = 0, q_rem = 0;

        //  MS_ASSERT( QstepX32 >= QP2QSTEP[0] && QstepX32 <= QP2QSTEP[51]);
        if( QstepX32 <= ct->m_nMinQStep)
            return ct->m_nMinQP;
        else if (QstepX32 > ct->m_nMaxQStep)
            return ct->m_nMaxQP;

        while( QstepX32 > rcQP2Qstep(ct, 5) )
        {
            QstepX32 >>= 1;
            q_per += 1;
        }

        if (QstepX32 <= 21)
        {
            //QstepX32 = 20;
            q_rem = 0;
        }
        else if (QstepX32 <= 24)
        {
            //QstepX32 = 22;
            q_rem = 1;
        }
        else if (QstepX32 <= 27)
        {
            //QstepX32 = 26;
            q_rem = 2;
        }
        else if (QstepX32 <= 30)
        {
            //QstepX32 = 28;
            q_rem = 3;
        }
        else if (QstepX32 <= 34)
        {
            //QstepX32 = 32;
            q_rem = 4;
        }
        else
        {
            //QstepX32 = 36;
            q_rem = 5;
        }

        return (q_per * 6 + q_rem);
    }
    else if (ct->m_nCodecType==REG_ENC_MODE_MPG4 || ct->m_nCodecType==REG_ENC_MODE_H263)
    {
        if( QstepX32 <= ct->m_nMinQStep)
            return ct->m_nMinQP;
        else if (QstepX32 > ct->m_nMaxQStep)
            return ct->m_nMaxQP;

        return QstepX32>>QS_SHIFT_FACTOR;
    }

    return 0;   // Should never entering this.
}

#ifdef _SUPPORT_MBLEVEL_RC_

#define DUMP_FRAME_NO -1L //140
// Each MB must call this routine once
MS_S32 cvbr_InitMB(CVBRRateControl* ct, MS_S32 nVar, const MS_S32 nPrevQP, const MS_S32 nBits, MS_S32 IsIntra, MS_S32 IsP4MV, MS_S32 BPredType, MS_S32 nResetDQ)
{
#ifdef USE_INT_PREC
	MS_S32 nAvgAct, nActj, nNBits=0;
#else
	MS_FLOAT fAvgAct, fActj, fNBits;
#endif
	MS_S32 QStep, RtnQP, nVariance;
//        MS_S32 TgtQP;
	MS_BOOL bChangeQP = 0;
	MS_S32 nMBX, nMBY;

#ifdef RAND_INPUT
	nVariance = nVar = rand()%128;
	//IsIntra = (rand()%4)==0 ? 1 : 0;
	//Is4MV = (rand()%4)==0 ? 1 : 0;
#else
	nVariance = nVar;
#endif

//     if (ct->m_nFrameCount == DUMP_FRAME_NO)
//         printf("ct->m_nMBN = %d (MBX, MBY) = (%2d, %2d), nBits = %d\n", ct->m_nMBN, ct->m_nMBN%ct->m_nMbWidth, ct->m_nMBN/ct->m_nMbWidth, nBits);

// 	if (ct->m_rcGranularity==FRAMELEVELRC) {
// 		return rcQstep2QP(ct->m_nFrameQStep);
// 	}

	if (ct->m_nMBN==0) { // Initialization
		ct->m_nSumAct = 0;
		ct->m_nTargetUsedBits = 0;
	}

	if (ct->m_nMBN>0)
	{ // Previous MB updating: Last MB is not counted!
		// Update QP
		ct->m_nPrevTopQP[(ct->m_nMBN-1)%ct->m_nMbWidth] = nPrevQP;
		ct->m_nLastFrameAvgQStep[ct->m_bIsBotField] += rcQP2Qstep(ct, nPrevQP);

		// SW simulation hw pipeline: Update bit usage history
		if (ct->m_nMBN<3)
			ct->m_nUsedBits[ct->m_nMBN-1] = nBits;
		else {
			ct->m_nUsedBits[0] = ct->m_nUsedBits[1];
			ct->m_nUsedBits[1] = nBits;
		}
	}

	if (ct->m_nMBN>1)	// HW pipeline: See below nNBits (or fNBits) calculation
		ct->m_nTargetUsedBits += ct->m_nTargetMbBits;

	// Update history
	if (nVariance==0) nVariance = 1;
	ct->m_nSumAct += nVariance;

	// QP calculation
	ct->m_nNewPacket = 0; // Default
	if (ct->m_nMBN<2) {
		RtnQP = rcQstep2QP(ct, ct->m_nFrameQStep);
	}
	else
	{
		if (ct->m_nCodecType==REG_ENC_MODE_MPG4 && (!IsIntra) && ((ct->m_nFrameType==P_VOP&&IsP4MV)||(ct->m_nFrameType==B_VOP&&BPredType==0))) {
			RtnQP = nPrevQP;	// Not allowing DQ!=0
		}
		else {
#ifdef USE_INT_PREC
			nNBits = (ct->m_nUsedBits[0]<<SCALE_BITS) / ct->m_nTargetUsedBits;
			//MS_ASSERT(nNBits<(1<<(SCALE_BITS+6)));
			if (nNBits>=(1<<(SCALE_BITS+6)))
				nNBits = (1<<(SCALE_BITS+6)) - 1;
			nAvgAct = ct->m_nSumAct / (ct->m_nMBN+1);
			nActj = (((nVariance<<1) + nAvgAct) << SCALE_ACT) / (nVariance + (nAvgAct<<1));
			// Target QStep
			if (ct->m_nFrameType==I_VOP)
				QStep = (MS_S32)(((MS_S64)ct->m_nFrameQStep * nActj) >> SCALE_ACT);
			else
				QStep = (MS_S32)(((MS_S64)ct->m_nFrameQStep * nActj * nNBits) >> (SCALE_ACT+SCALE_BITS));
#else
			fNBits = (MS_FLOAT)ct->m_nUsedBits[0] / ct->m_nTargetUsedBits;
			fAvgAct = (MS_FLOAT)ct->m_nSumAct / (ct->m_nMBN+1);
			fActj = ((nVariance*MBACT_NORMALIZATION_FACTOR) + fAvgAct) / (nVariance + (fAvgAct*MBACT_NORMALIZATION_FACTOR));
			// Target QStep
			if (ct->m_nFrameType==I_VOP)
				QStep = (MS_S32)(ct->m_nFrameQStep * fActj);
			else
				QStep = (MS_S32)(ct->m_nFrameQStep * fActj * fNBits);
#endif
			// 		if (QStep<(1<<QS_SHIFT_FACTOR))
			// 			QStep = (1<<QS_SHIFT_FACTOR);
			MS_ASSERT(QStep>=0 && QStep<(1<<20));

			// Target QP
			RtnQP = rcQstep2QP(ct, QStep);
			// Refinement: Phase 1, top and left MB-QP limitation
			if (ct->m_nMBN >= ct->m_nMbWidth) {
				if (RtnQP > ct->m_nPrevTopQP[ct->m_nMBN%ct->m_nMbWidth] + TOP_QP_DIFF_LIMIT) {
					RtnQP = ct->m_nPrevTopQP[ct->m_nMBN%ct->m_nMbWidth] + SPEC_QP_DIFF_LIMIT;
					bChangeQP = 1;
				}
				else if (RtnQP < ct->m_nPrevTopQP[ct->m_nMBN%ct->m_nMbWidth] - TOP_QP_DIFF_LIMIT) {
					RtnQP = ct->m_nPrevTopQP[ct->m_nMBN%ct->m_nMbWidth] - SPEC_QP_DIFF_LIMIT;
					bChangeQP = 1;
				}
			}
			if (RtnQP > nPrevQP + LEFT_QP_DIFF_LIMIT) {
				RtnQP = nPrevQP + SPEC_QP_DIFF_LIMIT;
				bChangeQP = 1;
			}
			else if (RtnQP < nPrevQP - LEFT_QP_DIFF_LIMIT) {
				RtnQP = nPrevQP - SPEC_QP_DIFF_LIMIT;
				bChangeQP = 1;
			}
			// Refinement: Phase 2, spec QP range limitation
			RtnQP = MSRC_MAX(ct->m_nMinQP, RtnQP);
			RtnQP = MSRC_MIN(ct->m_nMaxQP, RtnQP);
#if 0	// Don't need this because QP is bounded by rcQstep2QP(),
			// and if TOP_QP_DIFF_LIMIT and BOTTOM_QP_DIFF_LIMIT >=2, there is no way to have +-1.
			// Refinement: Phase 3, MPEG-4 B-frame limitation
			if (ct->m_nCodecType==REG_ENC_MODE_MPG4 && ct->m_nFrameType==B_VOP /*&& RtnQP!=nPrevQP*/) {
				if (RtnQP-nPrevQP==-1 || RtnQP-nPrevQP==1)
					RtnQP = nPrevQP;
			}
#endif
			// Avoid frequent QP changing
			if (!bChangeQP)
				RtnQP = nPrevQP; // Reset
		}

		//DEBUG_RC(("  [CVBRRC] %d : NBits=%d, AvgAct=%d\n", ct->m_nMBN, (MS_S32)fNBits, (MS_S32)fAvgAct ));

		//////////////////////////////////////////////////////////////////////////
		// er_en
		if (ct->m_nVPSize) {
			if (ct->m_nUsedBits[0]-ct->m_nLastVPBits>=ct->m_nVPSize) {
				if (ct->m_nVPMbRow) {
					nMBX = ct->m_nMBN%ct->m_nMbWidth;
					nMBY = ct->m_nMBN/ct->m_nMbWidth;
					if (nMBX==0 && nMBY>0 && (nMBY%ct->m_nVPMbRow)==0) {
						ct->m_nNewPacket = 1;
						ct->m_nLastVPBits = ct->m_nUsedBits[0];
					}
				}
				else {
					ct->m_nNewPacket = 1;
					ct->m_nLastVPBits = ct->m_nUsedBits[0];
				}
			}
		}
		else if (ct->m_nVPMbRow) {
			nMBX = ct->m_nMBN%ct->m_nMbWidth;
			nMBY = ct->m_nMBN/ct->m_nMbWidth;
			if (nMBX==0 && nMBY>0 && (nMBY%ct->m_nVPMbRow)==0) {
				ct->m_nNewPacket = 1;
				ct->m_nLastVPBits = ct->m_nUsedBits[0];
			}
		}
	}

	if (ct->m_rcGranularity==FRAMELEVELRC) {
		RtnQP = rcQstep2QP(ct, ct->m_nFrameQStep);
	}

	ct->m_nMBN++;
	if (ct->m_rcMethod==CONST_QUALITY)
		return ct->m_nConstQP;
	MS_ASSERT(RtnQP<=ct->m_nMaxQP && RtnQP>=ct->m_nMinQP);
	return RtnQP;
}

#else	// _SUPPORT_MBLEVEL_RC_ not defined

MS_S32 cvbr_InitMB(CVBRRateControl* ct, MS_S32 nVar, const MS_S32 nPrevQP, const MS_S32 nBits, MS_S32 IsIntra, MS_S32 IsP4MV, MS_S32 BPredType, MS_S32 nResetDQ)
{
	if (ct->m_nMBN>0)
		ct->m_nLastFrameAvgQStep[ct->m_bIsBotField] += rcQP2Qstep(nPrevQP);
	if (ct->m_rcMethod==CONST_QUALITY)
		return ct->m_nConstQP;
	return rcQstep2QP(ct->m_nFrameQStep);
}

#endif // _SUPPORT_MBLEVEL_RC_