JpgToBmp
来源：互联网 发布：java工程师个人技能 编辑：程序博客网 时间：2024/06/15 23:47
#include <stdio.h>
#include <alloc.h>
#include <math.h>
#define PI 3.1415927
#define widthbytes(i) ((i + 31) / 32 * 4 )
int sampleYH, sampleYV, sampleUH, sampleUV, sampleVH, sampleVV;
int HYtoU, VYtoU, HYtoV, VYtoV;
int YinMCU, UinMCU, VinMCU;
int compressnum = 0, Qt[3][64], codepos[4][16], codelen[4][16];
int *YQt, *UQt, *VQt ;
unsigned char compressindex[3], YDCindex, YACindex, UVDCindex, UVACindex;
unsigned char HufTabindex, And[9] = {0, 1, 3, 7, 0xf, 0x1f, 0x3f, 0x7f, 0xff};
unsigned int codevalue[4][256], hufmax[4][16], hufmin[4][16];
int bitpos = 0, curbyte = 0, run = 0, value = 0, MCUbuffer[10 * 64], blockbuffer[64];
int ycoef = 0, ucoef = 0, vcoef = 0, intervalflag = 0, interval = 0, restart = 0;
long Y[4 * 64], U[4 * 64], V[4 * 64], QtZMCUbuffer[10 * 64];
unsigned long imgwidth = 0, imgheight = 0, width =0, height = 0, linebytes;
int Z[8][8] = {{0, 1, 5, 6, 14, 15, 27, 28},
{2, 4, 7, 13, 16, 26, 29, 42},
{3, 8, 12, 17, 25, 30, 41, 43},
{9, 11, 18, 24, 31, 40, 44, 53},
{10, 19, 23, 32, 39, 45, 52, 54},
{20, 22, 33, 38, 46, 51, 55, 60},
{21, 34, 37, 47, 50, 56, 59, 61},
{35, 36, 48, 49, 57, 58, 62, 63}};
struct{
unsigned char type[2] ;
long size ;
long reserved ;
long offset ;
}head;
struct{
long size ;
long width ;
long height ;
int plane ;
int bitcount ;
long compression ;
long imagesize ;
long xpels ;
long ypels ;
long colorused ;
long colorimportant ;
}bmp ;
void error(char * s)
{
printf("%s/n", s) ;
exit(1) ;
}
void initialize( FILE * fp )
{
unsigned char *p, *q, hfindex, qtindex, number ;
int i, j, k, finish =0, huftab1, huftab2, huftabindex, count ;
unsigned int length, flag ;
fread(& flag, sizeof(unsigned int), 1, fp) ;
if(flag != 0xd8ff) /*SOI wrong 匹配SOI*/
error("Error Jpg File format SOI !") ;
while(! finish)
{
fread(& flag, sizeof(unsigned int), 1, fp) ; /*读取标记头*/
fread(&length, sizeof(unsigned int), 1, fp) ;
length = ((length << 8) | (length >> 8)) - 2 ; /*读取段长度 高低位调整*/
switch(flag)
{
case 0xe0ff: /*APPO 段*/
fseek(fp, length, 1) ;
break ;
case 0xdbff: /* DQT */
p = malloc(length) ;
fread(p, length, 1, fp) ; /* P指向（Pq,Tq) 共一个字节 Pq表精度 Tq表示 量化表编号 */
qtindex = (* p) & 0x0f ; /* 求Tq 用低四 */
q = p + 1 ; /* 量化表中第一个值 之字形排列 */
if(length + 2 <80) /* 量化表个数为1时 */
for(i = 0; i < 64; i ++)
Qt[qtindex][i] = (int) * (q ++) ;
else{
for(i = 0; i < 64; i ++)
Qt[qtindex][i] = (int) * (q ++) ;
qtindex = * (q ++ ) & 0x0f ; /* 求第二个量化表编号 */
for(i = 0; i < 64; i ++)
Qt[qtindex][i] = (int) * (q ++) ;
}
free(p) ;
break ;
case 0xc0ff: /* Start of Frame */
p = malloc(length) ;
fread(p, length, 1, fp) ; /* P指向SOF中 P */
imgheight = ((* (p + 1)) << 8) + (* (p + 2)) ; /* 图像高度 需要交换字节高低位顺序 */
imgwidth = ((* (p + 3)) << 8) + (* (p + 4)) ;
compressnum = * (p + 5) ; /* Frame 中成分个数 1代表灰度图 3代表真彩图 */
if((compressnum != 1) && (compressnum != 3))
error("Error Jpg File format SOF !") ;
if(compressnum == 3)
{
compressindex[0] = * (p + 6) ; /* Frame 成份 */
sampleYH = (* (p + 7)) >> 4 ; /* 对应成分水平取样因子 */
sampleYV = (* (p + 7)) & 0x0f ; /* 垂直取样因子 */
YQt = (int *) Qt[* (p + 8)] ; /* Y量化表编号 */
compressindex[1] = * (p + 9) ; /* 第二个成分 */
sampleUH = (*(p + 10)) >> 4 ;
sampleUV = (* (p + 10)) & 0x0f ;
UQt = (int *) Qt[* ( p + 11)] ;
compressindex[2] = * (p + 12) ;
sampleVH = (*(p + 13)) >> 4 ;
sampleVV = (* (p + 13)) & 0x0f ;
VQt = (int *) Qt[* (p + 14)] ; /* V成分量化表编号 */
}
else /* 灰度图像时 */
{
compressindex[0] = * (p + 6) ;
sampleYH = (* (p + 7)) >> 4 ;
sampleYV = (* (p + 7)) & 0x0f ;
YQt = (int *) Qt[* (p + 8)] ;
compressindex[1] = * (p + 6) ;
sampleUH = 1 ; /* U V 成分无效 */
sampleUV = 1;
UQt = (int *) Qt[* (p + 8)] ;
compressindex[2] = * (p + 6) ;
sampleVH = 1 ;
sampleVV = 1;
VQt = (int *) Qt[* (p + 8)] ;
}
free(p) ;
break ;
case 0xc4ff: /* DHT 段 */
p = malloc(length + 1) ;
fread(p, length,1, fp) ; /* P指向（Tc,Th）Tco 0rxj DC用HUF表 为1 指AC用HUF表 */
p[length] = 0xff ; /* 结尾标识 */
if(length + 2 < 0xd0) /* 只有一个DHT表时*/
{
huftab1 = (int) (*p) >> 4 ; /* huftab1 = Tc */
huftab2 = (int) (*p) & 0x0f ; /* huftab2 = Th */
huftabindex = huftab1 *2 + huftab2 ; /* huf表编号 */
q = p + 1 ;
for(i = 0; i < 16; i ++)
codelen[huftabindex][i] = (int) (* (q ++)) ;/* 第i字节表示了i位长的 Huffman代码的个数(i= 1到16)*/
j = 0 ;
for(i = 0; i < 16; i ++)
if(codelen[huftabindex][i] != 0)
{
k = 0 ;
while(k < codelen[huftabindex][i]) /*提取codelen[huftabindex][i]个i位长度编码*/
{
codevalue[huftabindex][k + j] = (int) (* (q ++)) ;/* 编码值*/
k ++ ;
} /*end while */
j += k ; /* 表的长度 (字节数) = 这 16 个数字之和*/
} /* end if */
i = 0 ;
while(codelen[huftabindex][i] == 0) /* 长度为i的编码没有*/
i ++ ;
for(j = 0; j < i; j ++)
{
hufmin[huftabindex][j] = 0 ; /* i位长度没有编码则编码最小值和最大值都置0 */
hufmax[huftabindex][j] = 0 ;
} /*end for */
hufmin[huftabindex][i] = 0 ; /* 编码最小值从0开始 */
hufmax[huftabindex][i] = codelen[huftabindex][i] - 1 ; /* 最大值与最小值的差值用hufmax 表示*/
for(j = i + 1; j < 16; j ++)
{
hufmin[huftabindex][j] = (hufmax[huftabindex][j - 1] + 1) << 1 ; /* 计算i位长度编码值 f(i)=2*(f(i-1)+1)*/
hufmax[huftabindex][j] = hufmin[huftabindex][j] + codelen[huftabindex][j] - 1 ; /* i位编码的最大编码值*/
} /* end ofr */
codepos[huftabindex][0] = 0 ; /* 编码值位置 */
for(j = 1; j < 16; j ++)
codepos[huftabindex][j] = codelen[huftabindex][j - 1] + codepos[huftabindex][j - 1] ; /* 前一编码位置+前一编码位长度 */
}
else
{
hfindex = * p ;
while(hfindex != 0xff)
{
huftab1 = (int) hfindex >> 4 ; /* huftab1 = Tc */
huftab2 = (int) hfindex & 0x0f ; /* huftab2 = Th */
huftabindex = huftab1 *2 + huftab2 ; /* huf表编号 */
q = p + 1 ;
count = 0 ;
for(i = 0; i < 16; i ++)
{
codelen[huftabindex][i] = (int) (* (q ++)) ;
count += codelen[huftabindex][i] ; /* 表的字节长度 */
} /* end for */
count += 17 ; /* Tc Th 及16个长度的字节 共17字节*/
j = 0 ;
for(i = 0; i < 16; i ++)
if(codelen[huftabindex][i] != 0) /* 以下内容同上处一个表时的处理*/
{
k = 0 ;
while(k < codelen[huftabindex][i])
{
codevalue[huftabindex][k + j] = (int) (* (q ++)) ;
k ++ ;
} /*end while */
j += k ;
} /*end if */
i = 0 ;
while(codelen[huftabindex][i] == 0)
i ++ ;
for(j = 0; j < i; j ++)
{
hufmin[huftabindex][j] = 0 ;
hufmax[huftabindex][j] = 0 ;
} /*end for */
hufmin[huftabindex][i] = 0 ;
hufmax[huftabindex][i] = codelen[huftabindex][i] - 1 ;
for(j = i + 1; j < 16; j ++)
{
hufmin[huftabindex][j] = (hufmax[huftabindex][j - 1] + 1) << 1 ;
hufmax[huftabindex][j] = hufmin[huftabindex][j] + codelen[huftabindex][j] - 1 ;
} /*end for */
codepos[huftabindex][0] = 0 ;
for(j = 1; j < 16; j ++)
codepos[huftabindex][j] = codelen[huftabindex][j - 1] + codepos[huftabindex][j - 1] ;
p += count ; /* p偏移至下一DHT表*/
hfindex = * p ;
} /* end while */
p -= length ;
} /*end else */
free(p) ;
break ;
case 0xddff: /* DRI 段 */
p = malloc(length) ;
fread(p, length, 1, fp) ;
restart = ((* p) << 8) | (* (p + 1)) ; /* MCU个数 字节顺序调整得结果 */
free(p) ;
break ;
case 0xdaff: /* start of scan 段 */
p = malloc(length * sizeof(unsigned char)) ;
fread(p, length, 1, fp) ;
number = * p ; /* Frame中成分的个数Ns */
if(number != compressnum)
error("Error Jpg File format here !") ;
q = p + 1 ; /* q为成分编号Csn */
for(i = 0; i <compressnum; i ++)
{
if(* q == compressindex[0]) /* 成分编号对应Y成分 */
{
YDCindex = (* (q + 1)) >> 4 ; /* Y成分DC编码表编号为YDCindex=Tdn */
YACindex = ((* (q + 1)) & 0x0f) + 2 ; /* Y成分AC编码表编号 */
} /* end if */
else
{
UVDCindex = (* (q + 1)) >> 4 ; /* U V DC编码表编号 */
UVACindex = ((* (q + 1)) & 0x0f) + 2 ;
} /*end else*/
q += 2 ;
} /* end for */
finish = 1 ;
free(p) ;
break ;
case 0xd9ff: /* EＯＩ */
error("Error Jpg File format EOI !") ;
break ;
default:
if((flag & 0xf000) != 0xd000)
fseek(fp, length, 1) ;
break ;
} /*end switch */
} /*end while */
} /* end initialize */
void makebmpheader(FILE * fp)
{
int i, j ;
unsigned long colorbits = 24, imagebytes ;
linebytes = widthbytes(colorbits * imgwidth) ;
imagebytes = (unsigned long) imgheight * linebytes ;
head.type[0] = 'B' ;
head.type[1] = 'M' ;
head.size = imagebytes + 0x36 ;
head.reserved = 0;
head.offset = 0x36 ;
fwrite(& head, sizeof(head), 1, fp) ;
bmp.size = 0x28 ; /* 40 bytes */
bmp.width = (long) imgwidth ;
bmp.height = (long) imgheight ;
bmp.plane = 1L ; /* 规定为１ */
bmp.bitcount = colorbits ;
bmp.compression = 0 ;
bmp.imagesize = imagebytes ;
bmp.xpels = 0xece ; /*???????????? */
bmp.ypels = 0xec4 ;
bmp.colorused = 0;
bmp.colorimportant = 0 ;
fwrite(&bmp, sizeof(bmp), 1, fp) ;
for(j = 0; j < imgheight; j ++ )
for(i = 0; i < linebytes; i ++ ) /*先全部置数据为0*/
fputc(0, fp) ;
}
void idct(long *p, int k)
{
long x, x0, x1, x2, x3, x4, x5, x6, x7 ;
x1 = p[k * 4] << 1 ;
x2 = p[k * 6] ;
x3 = p[k * 2] ;
x4 = p[k * 1] ;
x5 = p[k * 7] ;
x6 = p[k * 5] ;
x7 = p[k * 3] ;
x0 = (p[0] << 11) + 1024 ;
x= 565 * (x4 + x5) ;
x4 = x + 2276 * x4;
x5 = x- 3406 * x5 ;
x = 2408 * (x6 + x7) ;
x6 = x- 799 * x6 ;
x7 = x- 4017 * x7 ;
x = 1108 * (x3 + x2) ;
x2 = x- 3784 * x2 ;
x3 = x+ 1568 * x3 ;
x = x6 ;
x6 = x5 + x7 ;
x5 -= x7 ;
x7 = x0 + x1 ;
x0 -= x1 ;
x1 = x + x4 ;
x4 -= x ;
x = x5 ;
x5 = x7 - x3;
x7 += x3 ;
x3 = x0 + x2 ;
x0 -= x2 ;
x2 = ( 181 * (x4 + x) + 128) >> 8 ;
x4 = (181 * (x4 - x) + 128) >> 8 ;
p[0] = (x7 + x1) >> 11 ;
p[k * 1] = (x3 + x2) >> 11 ;
p[k * 2] = (x0 + x4) >> 11 ;
p[k * 3] = (x5 + x6) >> 11 ;
p[k * 4] = (x5 - x6) >> 11 ;
p[k * 5] = (x0 - x4) >> 11 ;
p[k * 6] = (x3 - x2) >> 11 ;
p[k * 7] = (x7 - x1) >> 11 ;
} /* end idct */
void IDCTint(long * metrix)
{
int i ;
for(i= 0; i < 8; i ++)
idct(metrix + 8 * i, 1) ;
for(i = 0; i< 8; i ++)
idct(metrix + i, 8) ;
}/* end IDCTint */
void IQtZBlock(int *s, long *d, int *pQt, int correct)
{
int i, j, tag ;
long *pbuffer, buffer[8][8] ;
for(i = 0; i < 8; i ++)
for(j = 0; j < 8; j ++)
{
tag = Z[i][j] ;
buffer[i][j] = (long) s[tag] * (long) pQt[tag] ;
}/* end for */
pbuffer = (long *) buffer ;
IDCTint(pbuffer) ;
for(i = 0; i < 8; i ++)
for(j = 0; j < 8; j ++)
d[i * 8 + j] = (buffer[i][j] >> 3) + correct ;
} /* end IQtBlock */
void IQtZMCU(int xx, int yy, int offset, int *pQt, int correct)
{
int i, j, *pMCUBuffer ;
long *pQtZMCUBuffer ;
pMCUBuffer = MCUbuffer + offset ;
pQtZMCUBuffer = QtZMCUbuffer + offset ;
for(i = 0; i < yy; i ++)
for(j = 0; j < xx; j ++)
IQtZBlock(pMCUBuffer + (i * xx + j) * 64, pQtZMCUBuffer + (i * xx + j) * 64, pQt, correct) ;
} /* end IQtZMCU */
void getYUV(int xx, int yy, long *buf, int offset)
{
int i, j, k, n ;
long *pQtZMCU ;
pQtZMCU = QtZMCUbuffer + offset ;
for(i = 0; i < yy; i ++)
for(j = 0; j < xx; j ++)
for(k = 0; k < 8; k ++)
for(n = 0; n < 8; n ++)
buf[(i * 8 + k) * sampleYH * 8 + j * 8 + n] = *pQtZMCU ++ ;
} /* end getYUV */
void savebmp(FILE *fp)
{
int i, j ;
unsigned char r, g, b;
long y, u, v, rr, gg, bb ;
for(i = 0; i < sampleYV * 8; i ++)
{
if((height + i) < imgheight)
{
fseek(fp, (unsigned long) (imgheight - height - i - 1) * linebytes + 3 * width + 54, 0) ;
for(j = 0; j < sampleYH * 8; j ++)
{
if((width + j) < imgwidth)
{
y = Y[i * 8 * sampleYH + j] ;
u = U[(i / VYtoU) * 8 * sampleYH + j / HYtoU] ;
v = V[(i / VYtoV) * 8 * sampleYH + j / HYtoV] ;
rr = ((y << 8) + 359 * v) >> 8 ;
gg = (( y << 8) - 88 * u - 183 * v) >> 8 ;
bb = (( y << 8) + 301 * u) >> 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 ;
fputc(b, fp) ;
fputc(g, fp) ;
fputc(r, fp) ;
} /* end if */
else
break ;
} /* end for */
} /* end if */
else
break ;
} /* end for */
} /* end savebmp */
void decode(FILE *fp1, FILE *fp2)
{
int Yinbuf, Uinbuf, Vinbuf ;
YinMCU = sampleYH * sampleYV ; /* y 分量在MCU中数据单元个数 数据单元 8*8阵*/
UinMCU = sampleUH * sampleUV ;
VinMCU = sampleVH * sampleVV ; /* v 分量在MCU中数据单元个数*/
HYtoU = sampleYH / sampleUH ; /* 水平方向y:u */
VYtoU = sampleYV / sampleUV ; /* 垂直方向y:u */
HYtoV = sampleYH / sampleVH ; /* 水平方向y:v */
VYtoV = sampleYH / sampleVV ;
Yinbuf = 0 ;
Uinbuf = YinMCU * 64 ; /* U分量在 MCU 中样点 */
Vinbuf = (YinMCU + UinMCU) * 64 ;
while(DecodeMCUBlock(fp1))
{
interval ++ ;
if((restart) && (interval % restart == 0))
intervalflag = 1 ;
else
intervalflag = 0 ;
IQtZMCU(sampleYH, sampleYV, Yinbuf, YQt, 128) ;
IQtZMCU(sampleUH, sampleUV, Uinbuf, UQt, 0) ;
IQtZMCU(sampleVH, sampleVV, Vinbuf, VQt, 0) ;
getYUV(sampleYH, sampleYV, Y, Yinbuf) ;
getYUV(sampleUH, sampleUV, U, Uinbuf) ;
getYUV(sampleVH, sampleVV, V, Vinbuf) ;
savebmp(fp2) ;
width += sampleYH * 8 ;
if(width >= imgwidth)
{
width = 0;
height += sampleYV * 8 ;
} /* end if */
if((width == 0) && (height >= imgheight))
break ;
} /*end while */
} /* end decode */
int HufBlock(FILE *fp, unsigned char dchufindex, unsigned char achufindex)
{
int i, count = 0 ;
HufTabindex = dchufindex ;
if(DecodeElement(fp) != 1)
return 0 ;
blockbuffer[count ++] = value ;
HufTabindex = achufindex ;
while(count < 64)
{
if(DecodeElement(fp) != 1)
return 0 ;
if((run == 0) && (value == 0))
{
for(i = count; i < 64; i ++)
blockbuffer[i] = 0 ;
count = 64 ;
} /* end if */
else
{
for(i = 0; i < run; i ++)
blockbuffer[count ++] = 0 ;
blockbuffer[count ++] = value ;
} /* end else */
} /* end while */
return 1 ;
} /* end HufBlock */
int DecodeMCUBlock(FILE *fp)
{
int i, j, *pMCUBuffer ;
if(intervalflag)
{
fseek(fp, 2, 1) ;
ycoef = ucoef = vcoef = 0 ;
bitpos = 0;
curbyte = 0 ;
} /* end if */
switch(compressnum){
case 3:
pMCUBuffer = MCUbuffer ;
for(i = 0; i < sampleYH * sampleYV; i ++)
{
if(HufBlock(fp, YDCindex, YACindex) != 1)
return 0 ;
blockbuffer[0] += ycoef ;
ycoef = blockbuffer[0] ;
for(j = 0; j < 64; j++)
*pMCUBuffer ++ = blockbuffer[j] ;
} /* end for */
for(i = 0; i < sampleUH * sampleUV; i++)
{
if(HufBlock(fp, UVDCindex, UVACindex) != 1)
return 0 ;
blockbuffer[0] += ucoef ;
ucoef = blockbuffer[0] ;
for(j = 0; j < 64; j++)
*pMCUBuffer ++ = blockbuffer[j] ;
} /* end for */
for(i = 0; i < sampleVH * sampleVV; i ++)
{
if(HufBlock(fp, UVDCindex, UVACindex) != 1)
return 0 ;
blockbuffer[0] += vcoef ;
vcoef = blockbuffer[0] ;
for(j = 0; j < 64; j ++)
*pMCUBuffer ++ = blockbuffer[j] ;
} /* end for*/
break ;
case 1:
pMCUBuffer = MCUbuffer ;
if(HufBlock(fp, YDCindex, YACindex) != 1)
return 0 ;
blockbuffer[0] += ycoef ;
ycoef = blockbuffer[0] ;
for(j = 0; j < 64 ; j ++)
*pMCUBuffer ++ = blockbuffer[j] ;
for(i = 0; i < 128; i ++)
*pMCUBuffer ++ = 0 ;
break ;
default:
error("Error Jpg File format! default") ;
} /* end switch */
return (1) ;
} /* end DecodeMCUBlock */
unsigned char readbyte(FILE *fp)
{
unsigned char c ;
c = fgetc(fp) ;
if(c == 0xff) /* 读入非0xff字节 */
fgetc(fp) ;
bitpos = 8 ;
curbyte = c;
return c ;
} /* end readbyte */
int DecodeElement(FILE *fp)
{
int codelength ;
long thiscode, tempcode ;
unsigned int temp, news ;
unsigned char hufbyte, runsize, tempsize, sign ;
unsigned char newbyte, lastbyte ;
if(bitpos >= 1)
{
bitpos -- ;
thiscode = (unsigned char) curbyte >> bitpos ;
curbyte = curbyte & And[bitpos] ;
} /* end if */
else
{
lastbyte = readbyte(fp) ;
bitpos -- ;
newbyte = curbyte & And[bitpos] ;
thiscode = lastbyte >> 7 ;
curbyte = newbyte ;
} /* end else */
codelength = 1 ;
while((thiscode < hufmin[HufTabindex][codelength - 1])
||(codelen[HufTabindex][codelength - 1] == 0)
||(thiscode > hufmax[HufTabindex][codelength - 1]))
{
if(bitpos >= 1)
{
bitpos -- ;
tempcode = (unsigned char) curbyte >> bitpos ;
curbyte = curbyte & And[bitpos] ;
} /* end if */
else
{
lastbyte = readbyte(fp) ;
bitpos -- ;
newbyte = curbyte & And[bitpos] ;
tempcode = (unsigned char) lastbyte >> 7 ;
curbyte = newbyte ;
} /* end else */
thiscode = (thiscode << 1) + tempcode ;
codelength ++ ;
if(codelength > 16)
error("Error Jpg File format! this") ;
} /* end while */
temp = thiscode - hufmin[HufTabindex][codelength - 1] + codepos[HufTabindex][codelength - 1] ;
hufbyte = (unsigned char) codevalue[HufTabindex][temp] ;
run = (int) (hufbyte >> 4) ;
runsize = hufbyte & 0x0f ;
if(runsize == 0)
{
value = 0 ;
return 1 ;
} /* end if */
tempsize = runsize ;
if(bitpos >= runsize)
{
bitpos -= runsize ;
news = (unsigned char) curbyte >> bitpos ;
curbyte = curbyte & And[bitpos] ;
} /* end if */
else
{
news = curbyte ;
tempsize -= bitpos ;
while(tempsize > 8)
{
lastbyte = readbyte(fp) ;
news =(news << 8) + (unsigned char) lastbyte ;
tempsize -= 8 ;
} /* end while */
lastbyte = readbyte(fp) ;
bitpos -= tempsize ;
news = (news << tempsize) + (lastbyte >> bitpos) ;
curbyte = lastbyte & And[bitpos] ;
} /* end else */
sign = news >> (runsize - 1) ;
if(sign)
value = news ;
else
{
news = news ^ 0xffff ;
temp = 0xffff << runsize ;
value = -(int) (news ^ temp) ;
} /* end else */
return 1 ;
} /* DecodeElement */
main( )
{
FILE *fp1, *fp2 ;
if((fp1 = fopen("Winter.jpg", "rb")) == NULL)
error("Can not open Jpg File in main! ") ;
if((fp2 = fopen("Winter.bmp", "wb")) == NULL)
error("Can not create Bmp File in main!") ;
initialize(fp1) ;
makebmpheader(fp2) ;
decode(fp1, fp2) ;
fclose(fp1) ;
fclose(fp2) ;
} /* end main */
