www.pudn.com > bmp2jpeg&jpegcoding.rar > compress.c
//////////////////////////////////////////////////////////////
//Name:compress.c
//Purpose: Run length algorithm and Jpeg decoding
//Author: phoenix, CS, TshingHua, Beijing, P.R.C.
//Email: bjlufengjun@www.163.net or lufengjun@hotmail.com
//Date:April 3, 1998
//header file
#include "bmp.h"
#include "jpeg.h"
#include "memory.h"
#include "math.h"
#include "stdio.h"
//macro definition
#define WIDTHBYTES(i) ((i+31)/32*4)
#define PI 3.1415926535
//define return value of function
#define FUNC_OK 0
#define FUNC_MEMORY_ERROR 1
#define FUNC_FILE_ERROR 2
#define FUNC_FORMAT_ERROR 3
//function declaration
int PASCAL WinMain (HANDLE, HANDLE, LPSTR, int);
LRESULT CALLBACK MainWndProc(HWND , UINT,WPARAM, LPARAM);
BOOL LoadPcxFile(HWND hWnd,char *BmpFileName);
void ReadPcxLine(unsigned char *p,FILE *fp);
//////////////////////////////////////////////////
//Jpeg functions
BOOL LoadJpegFile(HWND hWnd,char *BmpFileName);
void showerror(int funcret);
int InitTag();
void InitTable();
int Decode();
int DecodeMCUBlock();
int HufBlock(BYTE dchufindex,BYTE achufindex);
int DecodeElement();
void IQtIZzMCUComponent(short flag);
void IQtIZzBlock(short *s ,int * d,short flag);
void GetYUV(short flag);
void StoreBuffer();
BYTE ReadByte();
void Initialize_Fast_IDCT();
void Fast_IDCT(int * block);
void idctrow(int * blk);
void idctcol(int * blk);
//////////////////////////////////////////////////
//global variable declaration
BITMAPFILEHEADER bf;
BITMAPINFOHEADER bi;
HPALETTE hPalette=NULL;
HBITMAP hBitmap=NULL;
HGLOBAL hImgData=NULL;
DWORD NumColors;
DWORD LineBytes;
DWORD ImgWidth=0 , ImgHeight=0;
unsigned int PcxBytesPerLine;
LPSTR lpPtr;
//////////////////////////////////////////////////
//variables used in jpeg function
short SampRate_Y_H,SampRate_Y_V;
short SampRate_U_H,SampRate_U_V;
short SampRate_V_H,SampRate_V_V;
short H_YtoU,V_YtoU,H_YtoV,V_YtoV;
short Y_in_MCU,U_in_MCU,V_in_MCU;
unsigned char *lpJpegBuf;
unsigned char *lp;
short qt_table[3][64];
short comp_num;
BYTE comp_index[3];
BYTE YDcIndex,YAcIndex,UVDcIndex,UVAcIndex;
BYTE HufTabIndex;
short *YQtTable,*UQtTable,*VQtTable;
BYTE And[9]={0,1,3,7,0xf,0x1f,0x3f,0x7f,0xff};
short code_pos_table[4][16],code_len_table[4][16];
unsigned short code_value_table[4][256];
unsigned short huf_max_value[4][16],huf_min_value[4][16];
short BitPos,CurByte;
short rrun,vvalue;
short MCUBuffer[10*64];
int QtZzMCUBuffer[10*64];
short BlockBuffer[64];
short ycoef,ucoef,vcoef;
BOOL IntervalFlag;
short interval=0;
int Y[4*64],U[4*64],V[4*64];
DWORD sizei,sizej;
short restart;
static long iclip[1024];
static long *iclp;
///////////////////////////////////////////////////////////
int PASCAL WinMain (HANDLE hInstance, HANDLE hPrevInstance,
LPSTR lpszCmdLine, int nCmdShow)
{
MSG msg;
WNDCLASS wndclass;
HWND hWnd;
if ( ! hPrevInstance ){
wndclass.style = CS_HREDRAW | CS_VREDRAW;
wndclass.lpfnWndProc = MainWndProc;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = hInstance;
wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wndclass.hCursor = LoadCursor (NULL, IDC_ARROW);
wndclass.hbrBackground = GetStockObject (WHITE_BRUSH);
wndclass.lpszMenuName = "BMPMENU";
wndclass.lpszClassName = "phoenix ip system";
}
if ( ! RegisterClass (&wndclass) )
return FALSE;
hWnd = CreateWindow ("phoenix ip system","Run length algorithm and Jpeg decoding",
WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,CW_USEDEFAULT,
CW_USEDEFAULT, CW_USEDEFAULT, NULL,NULL,
hInstance, NULL);
if (!hWnd)
return FALSE;
ShowWindow (hWnd, SW_SHOWMAXIMIZED);
UpdateWindow (hWnd);
while ( GetMessage (&msg, NULL, 0, 0) ){
TranslateMessage (&msg);
DispatchMessage (&msg);
}
return msg.wParam;
}
////////////////////////////////////////////////////////////////
LRESULT CALLBACK MainWndProc(HWND hWnd, UINT message,WPARAM wParam, LPARAM lParam)
{
static HDC hDC,hMemDC;
PAINTSTRUCT ps;
switch (message){
case WM_PAINT:
{
hDC = BeginPaint(hWnd, &ps);
if (hBitmap)
{
hMemDC = CreateCompatibleDC(hDC);
if (hPalette)
{
SelectPalette (hDC, hPalette, FALSE);
SelectPalette (hMemDC, hPalette, FALSE);
RealizePalette (hDC);
}
SelectObject(hMemDC, hBitmap);
BitBlt(hDC, 0, 0, ImgWidth,ImgHeight, hMemDC, 0, 0, SRCCOPY);
DeleteDC(hMemDC);
}
EndPaint(hWnd, &ps);
break;
}
case WM_DESTROY: //注意释放内存和位图，调色板句柄
if(hBitmap!=NULL)
DeleteObject(hBitmap);
if(hPalette!=NULL)
DeleteObject(hPalette);
if(hImgData!=NULL){
GlobalUnlock(hImgData);
GlobalFree(hImgData);
}
PostQuitMessage (0);
return 0;
case WM_COMMAND:
switch (wParam){
case IDM_RUNLENGTH:
//注意重新分配内存和调色板，位图句柄时，先释放原来的
if(hBitmap!=NULL){
DeleteObject(hBitmap);
hBitmap=NULL;
}
if(hPalette!=NULL){
DeleteObject(hPalette);
hPalette=NULL;
}
if(hImgData!=NULL){
GlobalUnlock(hImgData);
GlobalFree(hImgData);
hImgData=NULL;
}
if(LoadPcxFile(hWnd,"c:\\test.pcx")) //成功，则重画窗口
InvalidateRect(hWnd,NULL,TRUE);
break;
case IDM_JPEG:
//注意重新分配内存和调色板，位图句柄时，先释放原来的
if(hBitmap!=NULL){
DeleteObject(hBitmap);
hBitmap=NULL;
}
if(hPalette!=NULL){
DeleteObject(hPalette);
hPalette=NULL;
}
if(hImgData!=NULL){
GlobalUnlock(hImgData);
GlobalFree(hImgData);
hImgData=NULL;
}
if(LoadJpegFile(hWnd,"c:\\test.jpg")) //成功，则重画窗口
InvalidateRect(hWnd,NULL,TRUE);
break;
case IDM_EXIT:
SendMessage(hWnd,WM_DESTROY,0,0L);
break;
}
break;
}
return DefWindowProc (hWnd, message, wParam, lParam);
}
////////////////////////////////////////////////////////////////
BOOL LoadPcxFile (HWND hWnd,char *PcxFileName)
{
//pcx header
typedef struct{
char manufacturer;
char version;
char encoding;
char bits_per_pixel;
WORD xmin,ymin;
WORD xmax,ymax;
WORD hres;
WORD vres;
char palette[48];
char reserved;
char colour_planes;
WORD bytes_per_line;
WORD palette_type;
char filler[58];
} PCXHEAD;
FILE *PCXfp;
PCXHEAD header;
LOGPALETTE *pPal;
HPALETTE hPrevPalette;
HDC hDc;
HLOCAL hPal;
DWORD ImgSize;
DWORD BufSize;
LPBITMAPINFOHEADER lpImgData;
DWORD i;
LONG x,y;
int PcxTag;
unsigned char LineBuffer[6400];
LPSTR lpPtr;
HFILE hfbmp;
if((PCXfp=fopen(PcxFileName,"rb"))==NULL){
MessageBox(hWnd,"File c:\\test.pcx not found!","Error Message",MB_OK|MB_ICONEXCLAMATION);
return FALSE;
}
fread((char*)&header,1,sizeof(PCXHEAD),PCXfp);
if(header.manufacturer!=0x0a){
MessageBox(hWnd,"Not a valid Pcx file!","Error Message",MB_OK|MB_ICONEXCLAMATION);
fclose(PCXfp);
return FALSE;
}
fseek(PCXfp,-769L,SEEK_END);
PcxTag=fgetc(PCXfp)&0xff;
if(PcxTag!=12){
MessageBox(hWnd,"Not a 256 colors Pcx file!","Error Message",MB_OK|MB_ICONEXCLAMATION);
fclose(PCXfp);
return FALSE;
}
//create new bitmapfileheader and bitmapinfoheader
memset((char *)&bf,0,sizeof(BITMAPFILEHEADER));
memset((char *)&bi,0,sizeof(BITMAPINFOHEADER));
bi.biSize=sizeof(BITMAPINFOHEADER);
bi.biWidth=header.xmax-header.xmin+1;
bi.biHeight=header.ymax-header.ymin+1;
bi.biPlanes=1;
bi.biBitCount=8;
bi.biCompression=BI_RGB;
ImgWidth=bi.biWidth;
ImgHeight=bi.biHeight;
NumColors=256;
LineBytes=(DWORD)WIDTHBYTES(bi.biWidth*bi.biBitCount);
ImgSize=(DWORD)LineBytes*bi.biHeight;
bf.bfType=0x4d42;
bf.bfSize=sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER)+NumColors*sizeof(RGBQUAD)+ImgSize;
bf.bfOffBits=(DWORD)(NumColors*sizeof(RGBQUAD)+sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER));
if((hImgData=GlobalAlloc(GHND,(DWORD)(sizeof(BITMAPINFOHEADER)+
NumColors*sizeof(RGBQUAD)+ImgSize)))==NULL)
{
MessageBox(hWnd,"Error alloc memory!","ErrorMessage",MB_OK|
MB_ICONEXCLAMATION);
fclose(PCXfp);
return FALSE;
}
lpImgData=(LPBITMAPINFOHEADER)GlobalLock(hImgData);
memcpy(lpImgData,(char *)&bi,sizeof(BITMAPINFOHEADER));
lpPtr=(char *)lpImgData+sizeof(BITMAPINFOHEADER);
hPal=LocalAlloc(LHND,sizeof(LOGPALETTE) + NumColors* sizeof(PALETTEENTRY));
pPal =(LOGPALETTE *)LocalLock(hPal);
pPal->palNumEntries =256;
pPal->palVersion = 0x300;
for (i = 0; i < 256; i++) {
pPal->palPalEntry[i].peRed=(BYTE)fgetc(PCXfp);
pPal->palPalEntry[i].peGreen=(BYTE)fgetc(PCXfp);
pPal->palPalEntry[i].peBlue=(BYTE)fgetc(PCXfp);
pPal->palPalEntry[i].peFlags=(BYTE)0;
*(lpPtr++)=(unsigned char)pPal->palPalEntry[i].peBlue;
*(lpPtr++)=(unsigned char)pPal->palPalEntry[i].peGreen;
*(lpPtr++)=(unsigned char)pPal->palPalEntry[i].peRed;
*(lpPtr++)=0;
}
hPalette=CreatePalette(pPal);
LocalUnlock(hPal);
LocalFree(hPal);
hDc=GetDC(hWnd);
if(hPalette){
hPrevPalette=SelectPalette(hDc,hPalette,FALSE);
RealizePalette(hDc);
}
PcxBytesPerLine=(unsigned int)header.bytes_per_line;
fseek(PCXfp,(LONG)sizeof(PCXHEAD),SEEK_SET);
BufSize=bf.bfSize-sizeof(BITMAPFILEHEADER);
for(y=0;y>4;
SampRate_Y_V=(*(lp+9))&0x0f;
YQtTable=(short *)qt_table[*(lp+10)];
comp_index[1]=*(lp+11);
SampRate_U_H=(*(lp+12))>>4;
SampRate_U_V=(*(lp+12))&0x0f;
UQtTable=(short *)qt_table[*(lp+13)];
comp_index[2]=*(lp+14);
SampRate_V_H=(*(lp+15))>>4;
SampRate_V_V=(*(lp+15))&0x0f;
VQtTable=(short *)qt_table[*(lp+16)];
}
else{
comp_index[0]=*(lp+8);
SampRate_Y_H=(*(lp+9))>>4;
SampRate_Y_V=(*(lp+9))&0x0f;
YQtTable=(short *)qt_table[*(lp+10)];
comp_index[1]=*(lp+8);
SampRate_U_H=1;
SampRate_U_V=1;
UQtTable=(short *)qt_table[*(lp+10)];
comp_index[2]=*(lp+8);
SampRate_V_H=1;
SampRate_V_V=1;
VQtTable=(short *)qt_table[*(lp+10)];
}
lp+=llength;
break;
case M_DHT:
llength=MAKEWORD(*(lp+1),*lp);
if (llength<0xd0){
huftab1=(short)(*(lp+2))>>4; //huftab1=0,1
huftab2=(short)(*(lp+2))&0x0f; //huftab2=0,1
huftabindex=huftab1*2+huftab2;
lptemp=lp+3;
for (i=0; i<16; i++)
code_len_table[huftabindex][i]=(short)(*(lptemp++));
j=0;
for (i=0; i<16; i++)
if(code_len_table[huftabindex][i]!=0){
k=0;
while(k>4; //huftab1=0,1
huftab2=(short)hf_table_index&0x0f; //huftab2=0,1
huftabindex=huftab1*2+huftab2;
lptemp=lp+1;
ccount=0;
for (i=0; i<16; i++){
code_len_table[huftabindex][i]=(short)(*(lptemp++));
ccount+=code_len_table[huftabindex][i];
}
ccount+=17;
j=0;
for (i=0; i<16; i++)
if(code_len_table[huftabindex][i]!=0){
k=0;
while(k>4; //Y
YAcIndex=((*(lptemp+1))&0x0f)+2;
}
else{
UVDcIndex=(*(lptemp+1))>>4; //U,V
UVAcIndex=((*(lptemp+1))&0x0f)+2;
}
lptemp+=2;
}
lp+=llength;
finish=TRUE;
break;
case M_EOI:
return FUNC_FORMAT_ERROR;
break;
default:
if ((id&0xf0)!=0xd0){
llength=MAKEWORD(*(lp+1),*lp);
lp+=llength;
}
else lp+=2;
break;
} //switch
} //while
return FUNC_OK;
}
/////////////////////////////////////////////////////////////////
void InitTable()
{
short i,j;
sizei=sizej=0;
ImgWidth=ImgHeight=0;
rrun=vvalue=0;
BitPos=0;
CurByte=0;
IntervalFlag=FALSE;
restart=0;
for(i=0;i<3;i++)
for(j=0;j<64;j++)
qt_table[i][j]=0;
comp_num=0;
HufTabIndex=0;
for(i=0;i<3;i++)
comp_index[i]=0;
for(i=0;i<4;i++)
for(j=0;j<16;j++){
code_len_table[i][j]=0;
code_pos_table[i][j]=0;
huf_max_value[i][j]=0;
huf_min_value[i][j]=0;
}
for(i=0;i<4;i++)
for(j=0;j<256;j++)
code_value_table[i][j]=0;
for(i=0;i<10*64;i++){
MCUBuffer[i]=0;
QtZzMCUBuffer[i]=0;
}
for(i=0;i<64;i++){
Y[i]=0;
U[i]=0;
V[i]=0;
BlockBuffer[i]=0;
}
ycoef=ucoef=vcoef=0;
}
/////////////////////////////////////////////////////////////////////////
int Decode()
{
int funcret;
Y_in_MCU=SampRate_Y_H*SampRate_Y_V;
U_in_MCU=SampRate_U_H*SampRate_U_V;
V_in_MCU=SampRate_V_H*SampRate_V_V;
H_YtoU=SampRate_Y_H/SampRate_U_H;
V_YtoU=SampRate_Y_V/SampRate_U_V;
H_YtoV=SampRate_Y_H/SampRate_V_H;
V_YtoV=SampRate_Y_V/SampRate_V_V;
Initialize_Fast_IDCT();
while((funcret=DecodeMCUBlock())==FUNC_OK){
interval++;
if((restart)&&(interval % restart==0))
IntervalFlag=TRUE;
else
IntervalFlag=FALSE;
IQtIZzMCUComponent(0);
IQtIZzMCUComponent(1);
IQtIZzMCUComponent(2);
GetYUV(0);
GetYUV(1);
GetYUV(2);
StoreBuffer();
sizej+=SampRate_Y_H*8;
if(sizej>=ImgWidth){
sizej=0;
sizei+=SampRate_Y_V*8;
}
if ((sizej==0)&&(sizei>=ImgHeight))
break;
}
return funcret;
}
/////////////////////////////////////////////////////////////////////////////////////////
void GetYUV(short flag)
{
short H,VV;
short i,j,k,h;
int *buf;
int *pQtZzMCU;
switch(flag){
case 0:
H=SampRate_Y_H;
VV=SampRate_Y_V;
buf=Y;
pQtZzMCU=QtZzMCUBuffer;
break;
case 1:
H=SampRate_U_H;
VV=SampRate_U_V;
buf=U;
pQtZzMCU=QtZzMCUBuffer+Y_in_MCU*64;
break;
case 2:
H=SampRate_V_H;
VV=SampRate_V_V;
buf=V;
pQtZzMCU=QtZzMCUBuffer+(Y_in_MCU+U_in_MCU)*64;
break;
}
for (i=0;i>8;
gg=((y<<8)-159*u-220*v)>>8;
bb=((y<<8)+411*u-29*v)>>8;
R=(unsigned char)rr;
G=(unsigned char)gg;
B=(unsigned char)bb;
if (rr&0xffffff00) if (rr>255) R=255; else if (rr<0) R=0;
if (gg&0xffffff00) if (gg>255) G=255; else if (gg<0) G=0;
if (bb&0xffffff00) if (bb>255) B=255; else if (bb<0) B=0;
*lpbmp++=B;
*lpbmp++=G;
*lpbmp++=R;
}
else break;
}
}
else break;
}
}
///////////////////////////////////////////////////////////////////////////////
int DecodeMCUBlock()
{
short *lpMCUBuffer;
short i,j;
int funcret;
if (IntervalFlag){
lp+=2;
ycoef=ucoef=vcoef=0;
BitPos=0;
CurByte=0;
}
switch(comp_num){
case 3:
lpMCUBuffer=MCUBuffer;
for (i=0;i=1){
BitPos--;
thiscode=(BYTE)CurByte>>BitPos;
CurByte=CurByte&And[BitPos];
}
else{
lastbyte=ReadByte();
BitPos--;
newbyte=CurByte&And[BitPos];
thiscode=lastbyte>>7;
CurByte=newbyte;
}
codelen=1;
while ((thiscodehuf_max_value[HufTabIndex][codelen-1]))
{
if(BitPos>=1){
BitPos--;
tempcode=(BYTE)CurByte>>BitPos;
CurByte=CurByte&And[BitPos];
}
else{
lastbyte=ReadByte();
BitPos--;
newbyte=CurByte&And[BitPos];
tempcode=(BYTE)lastbyte>>7;
CurByte=newbyte;
}
thiscode=(thiscode<<1)+tempcode;
codelen++;
if(codelen>16)
return FUNC_FORMAT_ERROR;
} //while
temp=thiscode-huf_min_value[HufTabIndex][codelen-1]+code_pos_table[HufTabIndex][codelen-1];
hufexbyte=(BYTE)code_value_table[HufTabIndex][temp];
rrun=(short)(hufexbyte>>4);
runsize=hufexbyte&0x0f;
if(runsize==0){
vvalue=0;
return FUNC_OK;
}
tempsize=runsize;
if(BitPos>=runsize){
BitPos-=runsize;
valueex=(BYTE)CurByte>>BitPos;
CurByte=CurByte&And[BitPos];
}
else{
valueex=CurByte;
tempsize-=BitPos;
while(tempsize>8){
lastbyte=ReadByte();
valueex=(valueex<<8)+(BYTE)lastbyte;
tempsize-=8;
} //while
lastbyte=ReadByte();
BitPos-=tempsize;
valueex=(valueex<>BitPos);
CurByte=lastbyte&And[BitPos];
} //else
sign=valueex>>(runsize-1);
if(sign)
vvalue=valueex;
else{
valueex=valueex^0xffff;
temp=0xffff<255) ? 255 : i);
}
////////////////////////////////////////////////////////////////////////
void idctrow(int * blk)
{
int x0, x1, x2, x3, x4, x5, x6, x7, x8;
//intcut
if (!((x1 = blk[4]<<11) | (x2 = blk[6]) | (x3 = blk[2]) |
(x4 = blk[1]) | (x5 = blk[7]) | (x6 = blk[5]) | (x7 = blk[3])))
{
blk[0]=blk[1]=blk[2]=blk[3]=blk[4]=blk[5]=blk[6]=blk[7]=blk[0]<<3;
return;
}
x0 = (blk[0]<<11) + 128; // for proper rounding in the fourth stage
//first stage
x8 = W7*(x4+x5);
x4 = x8 + (W1-W7)*x4;
x5 = x8 - (W1+W7)*x5;
x8 = W3*(x6+x7);
x6 = x8 - (W3-W5)*x6;
x7 = x8 - (W3+W5)*x7;
//second stage
x8 = x0 + x1;
x0 -= x1;
x1 = W6*(x3+x2);
x2 = x1 - (W2+W6)*x2;
x3 = x1 + (W2-W6)*x3;
x1 = x4 + x6;
x4 -= x6;
x6 = x5 + x7;
x5 -= x7;
//third stage
x7 = x8 + x3;
x8 -= x3;
x3 = x0 + x2;
x0 -= x2;
x2 = (181*(x4+x5)+128)>>8;
x4 = (181*(x4-x5)+128)>>8;
//fourth stage
blk[0] = (x7+x1)>>8;
blk[1] = (x3+x2)>>8;
blk[2] = (x0+x4)>>8;
blk[3] = (x8+x6)>>8;
blk[4] = (x8-x6)>>8;
blk[5] = (x0-x4)>>8;
blk[6] = (x3-x2)>>8;
blk[7] = (x7-x1)>>8;
}
//////////////////////////////////////////////////////////////////////////////
void idctcol(int * blk)
{
int x0, x1, x2, x3, x4, x5, x6, x7, x8;
//intcut
if (!((x1 = (blk[8*4]<<8)) | (x2 = blk[8*6]) | (x3 = blk[8*2]) |
(x4 = blk[8*1]) | (x5 = blk[8*7]) | (x6 = blk[8*5]) | (x7 = blk[8*3])))
{
blk[8*0]=blk[8*1]=blk[8*2]=blk[8*3]=blk[8*4]=blk[8*5]
=blk[8*6]=blk[8*7]=iclp[(blk[8*0]+32)>>6];
return;
}
x0 = (blk[8*0]<<8) + 8192;
//first stage
x8 = W7*(x4+x5) + 4;
x4 = (x8+(W1-W7)*x4)>>3;
x5 = (x8-(W1+W7)*x5)>>3;
x8 = W3*(x6+x7) + 4;
x6 = (x8-(W3-W5)*x6)>>3;
x7 = (x8-(W3+W5)*x7)>>3;
//second stage
x8 = x0 + x1;
x0 -= x1;
x1 = W6*(x3+x2) + 4;
x2 = (x1-(W2+W6)*x2)>>3;
x3 = (x1+(W2-W6)*x3)>>3;
x1 = x4 + x6;
x4 -= x6;
x6 = x5 + x7;
x5 -= x7;
//third stage
x7 = x8 + x3;
x8 -= x3;
x3 = x0 + x2;
x0 -= x2;
x2 = (181*(x4+x5)+128)>>8;
x4 = (181*(x4-x5)+128)>>8;
//fourth stage
blk[8*0] = iclp[(x7+x1)>>14];
blk[8*1] = iclp[(x3+x2)>>14];
blk[8*2] = iclp[(x0+x4)>>14];
blk[8*3] = iclp[(x8+x6)>>14];
blk[8*4] = iclp[(x8-x6)>>14];
blk[8*5] = iclp[(x0-x4)>>14];
blk[8*6] = iclp[(x3-x2)>>14];
blk[8*7] = iclp[(x7-x1)>>14];
}