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1、将JPEG文件转换为BMP文件#include <stdio.h>#include <malloc.h>#include <math.h>#include <stdlib.h>#define PI 3.1415927 #define widthbytes(i) (i+31)/32*4) int sampleYH,sampleYV,sampleUH,sampleUV,sampleVH,sampleVV; int HYtoU,VYtoU,HYtoV,VYtoV,YinMCU,UinMCU,VinMCU; int compressnum=0,Qt364,*YQt,*U
2、Qt,*VQt,codepos416,codelen416; unsigned char compressindex3,YDCindex,YACindex,UVDCindex,UVACindex; unsigned char HufTabindex,And9=0,1,3,7,0xf,0x1f,0x3f,0x7f,0xff; unsigned int codevalue4256,hufmax416,hufmin416; int bitpos=0,curbyte=0,run=0,value=0,MCUbuffer10*64,blockbuffer64; int ycoef=0,ucoef=0,vc
3、oef=0,intervalflag=0,interval=0,restart=0; long Y4*64,U4*64,V4*64,QtZMCUbuffer10*64; unsigned long imgwidth=0,imgheight=0,width=0,height=0,linebytes; int Z88=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
4、,37,47,50,56,59,61,35,36,48,49,57,58,62,63; struct unsigned char type2; 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
5、 *s) printf(%sn,s); exit(1); void makebmpheader(FILE *fp) int i,j; unsigned long colorbits,imagebytes; colorbits=24; linebytes=widthbytes(colorbits*imgwidth); imagebytes=(unsigned long)imgheight*linebytes; head.type0=B;head.type1=M; head.size=imagebytes+0x36; head.reserved=0; head.offset=0x36; fwrit
6、e(&head,sizeof(head),1,fp); bmp.size=0x28; bmp.width=(long)imgwidth; bmp.height=(long)imgheight; bmp.plane=1L; bmp.bitcount=colorbits; pression=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
7、+) for(i=0;i<linebytes;i+) fputc(0,fp); 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) error(Error Jpg File format!); while(!finish) fread
8、(&flag,sizeof(unsigned int),1,fp); fread(&length,sizeof(int),1,fp); length=(length<<8)|(length>>8)-2; switch(flag) case 0xe0ff: fseek(fp,length,1);break; case 0xdbff: p=malloc(length); fread(p,length,1,fp); qtindex=(*p)&0x0f; q=p+1; if(length+2<80) for(i=0;i<64;i+) Qtqtindexi=(int)*(q+);
9、 else for(i=0;i<64;i+) Qtqtindexi=(int)*(q+); qtindex=*(q+)&0x0f; for(i=0;i<64;i+) Qtqtindexi=(int)*(q+); free(p);break; case 0xc0ff: p=malloc(length); fread(p,length,1,fp); imgheight=(*(p+1)<<8)+(*(p+2); imgwidth=(*(p+3)<<8)+(*(p+4); compressnum=*(p+5); if(compressnum!=1)&(compressnum!=
10、3) error(Error Jpg File format!); if(compressnum=3) compressindex0=*(p+6); sampleYH=(*(p+7)>>4; sampleYV=(*(p+7)&0x0f; YQt=(int *)Qt*(p+8); compressindex1=*(p+9); sampleUH=(*(p+10)>>4; sampleUV=(*(p+10)&0x0f; UQt=(int *)Qt*(p+11); compressindex2=*(p+12); sampleVH=(*(p+13)>>4; sampleVV=(*
11、(p+13)&0x0f; VQt=(int *)Qt*(p+14); else compressindex0=*(p+6); sampleYH=(*(p+7)>>4; sampleYV=(*(p+7)&0x0f; YQt=(int *)Qt*(p+8); compressindex1=*(p+6); sampleUH=1; sampleUV=1; UQt=(int *)Qt*(p+8); compressindex2=*(p+6); sampleVH=1; sampleVV=1; VQt=(int *)Qt*(p+8); free(p);break; case 0xc4ff: p=ma
12、lloc(length+1); fread(p,length,1,fp); plength=0xff; if(length+2<0xd0) huftab1=(int)(*p)>>4; huftab2=(int)(*p)&0x0f; huftabindex=huftab1*2+huftab2; q=p+1; for(i=0;i<16;i+) codelenhuftabindexi=(int)(*(q+); j=0; for(i=0;i<16;i+) if(codelenhuftabindexi!=0) k=0; while(k<codelenhuftabindexi) c
13、odevaluehuftabindexk+j=(int)(*(q+); k+; j+=k; i=0; while(codelenhuftabindexi=0) i+; for(j=0;j<i;j+) hufminhuftabindexj=0; hufmaxhuftabindexj=0; hufminhuftabindexi=0; hufmaxhuftabindexi=codelenhuftabindexi-1; for(j=i+1;j<16;j+) hufminhuftabindexj=(hufmaxhuftabindexj-1+1)<<1; hufmaxhuftabindex
14、j=hufminhuftabindexj+codelenhuftabindexj-1; codeposhuftabindex0=0; for(j=1;j<16;j+) codeposhuftabindexj=codelenhuftabindexj-1+codeposhuftabindexj-1; else hfindex=*p; while(hfindex!=0xff) huftab1=(int)hfindex>>4; huftab2=(int)hfindex&0x0f; huftabindex=huftab1*2+huftab2; q=p+1; count=0; for(i=0;
15、i<16;i+) codelenhuftabindexi=(int)(*(q+); count+=codelenhuftabindexi; count+=17; j=0; for(i=0;i<16;i+) if(codelenhuftabindexi!=0) k=0; while(k<codelenhuftabindexi) codevaluehuftabindexk+j=(int)(*(q+); k+; j+=k; i=0; while(codelenhuftabindexi=0) i+; for(j=0;j<i;j+) hufminhuftabindexj=0; hufma
16、xhuftabindexj=0; hufminhuftabindexi=0; hufmaxhuftabindexi=codelenhuftabindexi-1; for(j=i+1;j<16;j+) hufminhuftabindexj=(hufmaxhuftabindexj-1+1)<<1; hufmaxhuftabindexj=hufminhuftabindexj+codelenhuftabindexj-1; codeposhuftabindex0=0; for(j=1;j<16;j+) codeposhuftabindexj=codelenhuftabindexj-1+c
17、odeposhuftabindexj-1; p+=count; hfindex=*p; p-=length; free(p);break; case 0xddff: p=malloc(length); fread(p,length,1,fp); restart=(*p)<<8)|(*(p+1); free(p);break; case 0xdaff: p=malloc(length*sizeof(unsigned char); fread(p,length,1,fp); number=*p; if(number!=compressnum) error(Error Jpg File fo
18、rmat!); q=p+1; for(i=0;i<compressnum;i+) if(*q=compressindex0) YDCindex=(*(q+1)>>4; YACindex=(*(q+1)&0x0f)+2; else UVDCindex=(*(q+1)>>4; UVACindex=(*(q+1)&0x0f)+2; q+=2; finish=1; free(p);break; case 0xd9ff: error(Error Jpg File format!);break; default: if(flag&0xf000)!=0xd000) fseek(fp,le
19、ngth,1); break; 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=Yi*8*sampleYH+j; u=U(i/VYtoU)*8*
20、sampleYH+j/HYtoU; v=V(i/VYtoV)*8*sampleYH+j/HYtoV; /*rr=y+(359*v)>>8;gg=y-(88*u-183*v)>>8);bb=(y<<8)+301*u)>>8; */rr=(long)(y+1.402*v);gg=(long)(y-0.34414*u-0.71414*v);bb=(long)(y+1.772*u);r=(unsigned char)rr; g=(unsigned char)gg; b=(unsigned char)bb; if(rr&0xffffff00) if (rr>255)
21、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); else break; else break; unsigned char readbyte(FILE *fp) unsigned char c; c=fgetc(fp); if(c=0xff) fgetc(fp); bit
22、pos=8; curbyte=c; return c; int DecodeElement(FILE *fp) int codelength; long thiscode,tempcode; unsigned int temp,new; unsigned char hufbyte,runsize,tempsize,sign; unsigned char newbyte,lastbyte; if(bitpos>=1) bitpos-; thiscode=(unsigned char)curbyte>>bitpos; curbyte=curbyte&Andbitpos; else la
23、stbyte=readbyte(fp); bitpos-; newbyte=curbyte&Andbitpos; thiscode=lastbyte>>7; curbyte=newbyte; codelength=1; while(thiscode<hufminHufTabindexcodelength-1)| (codelenHufTabindexcodelength-1=0)| (thiscode>hufmaxHufTabindexcodelength-1) if(bitpos>=1) bitpos-; tempcode=(unsigned char)curbyte&g
24、t>bitpos; curbyte=curbyte&Andbitpos; else lastbyte=readbyte(fp); bitpos-; newbyte=curbyte&Andbitpos; tempcode=(unsigned char)lastbyte>>7; curbyte=newbyte; thiscode=(thiscode<<1)+tempcode; codelength+; if(codelength>16) error(Error Jpg File format!); temp=thiscode-hufminHufTabindexcodelen
25、gth-1+codeposHufTabindexcodelength-1; hufbyte=(unsigned char)codevalueHufTabindextemp; run=(int)(hufbyte>>4); runsize=hufbyte&0x0f; if(runsize=0) value=0; return 1; tempsize=runsize; if(bitpos>=runsize) bitpos-=runsize; new=(unsigned char)curbyte>>bitpos; curbyte=curbyte&Andbitpos; else ne
26、w=curbyte; tempsize-=bitpos; while(tempsize>8) lastbyte=readbyte(fp); new=(new<<8)+(unsigned char)lastbyte; tempsize-=8; lastbyte=readbyte(fp); bitpos-=tempsize; new=(new<<tempsize)+(lastbyte>>bitpos); curbyte=lastbyte&Andbitpos; sign=new>>(runsize-1); if(sign) value=new; else new=
27、new0xffff; temp=0xffff<<runsize; value=-(int)(newtemp); return 1; int HufBlock(FILE *fp,unsigned char dchufindex, unsigned char achufindex) int i,count=0; HufTabindex=dchufindex; if(DecodeElement(fp)!=1) return 0; blockbuffercount+=value; HufTabindex=achufindex; while (count<64) if(DecodeEleme
28、nt(fp)!=1) return 0; if(run=0)&(value=0) for(i=count;i<64;i+) blockbufferi=0; count=64; else for(i=0;i<run;i+) blockbuffercount+=0; blockbuffercount+=value; return 1; int DecodeMCUBlock(FILE *fp) int i,j,*pMCUBuffer; if(intervalflag) fseek(fp,2,1); ycoef=ucoef=vcoef=0; bitpos=0; curbyte=0; switc
29、h(compressnum) case 3: pMCUBuffer=MCUbuffer; for(i=0;i<sampleYH*sampleYV;i+) if(HufBlock(fp,YDCindex,YACindex)!=1) return 0; blockbuffer0=blockbuffer0+ycoef; ycoef=blockbuffer0; for(j=0;j<64;j+) *pMCUBuffer+=blockbufferj; for(i=0;i<sampleUH*sampleUV;i+) if(HufBlock(fp,UVDCindex,UVACindex)!=1)
30、return 0; blockbuffer0=blockbuffer0+ucoef; ucoef=blockbuffer0; for(j=0;j<64;j+) *pMCUBuffer+=blockbufferj; for(i=0;i<sampleVH*sampleVV;i+) if(HufBlock(fp,UVDCindex,UVACindex)!=1) return 0; blockbuffer0=blockbuffer0+vcoef; vcoef=blockbuffer0; for(j=0;j<64;j+) *pMCUBuffer+=blockbufferj; break; c
31、ase 1: pMCUBuffer=MCUbuffer; if(HufBlock(fp,YDCindex,YACindex)!=1) return 0; blockbuffer0=blockbuffer0+ycoef; ycoef=blockbuffer0; for(j=0;j<64;j+) *pMCUBuffer+=blockbufferj; for(i=0;i<128;i+) *pMCUBuffer+=0; break; default: error(Error Jpg File format); return(1); void idct(long *p,int k) long x
32、,x0,x1,x2,x3,x4,x5,x6,x7; x1=pk*4<<11;x2=pk*6;x3=pk*2;x4=pk*1; x5=pk*7;x6=pk*5;x7=pk*3;x0=(p0<<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-
33、x3;x7+=x3;x3=x0+x2;x0-=x2; x2=(181*(x4+x)+128)>>8;x4=(181*(x4-x)+128)>>8; p0=(x7+x1)>>11;pk*1=(x3+x2)>>11; pk*2=(x0+x4)>>11;pk*3=(x5+x6)>>11; pk*4=(x5-x6)>>11;pk*5=(x0-x4)>>11; pk*6=(x3-x2)>>11;pk*7=(x7-x1)>>11; void IDCTint(long *metrix) int i; for(i=0;i<8;
34、i+) idct(metrix+8*i,1); for(i=0;i<8;i+) idct(metrix+i,8); void IQtZBlock(int *s,long *d,int *pQt,int correct) int i,j,tag; long *pbuffer,buffer88; for(i=0;i<8;i+) for(j=0;j<8;j+) tag=Zij; bufferij=(long)stag*(long)pQttag; pbuffer=(long *)buffer; IDCTint(pbuffer); for(i=0;i<8;i+) for(j=0;j<
35、8;j+) di*8+j=(bufferij>>3)+correct; 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)*
36、64,pQt,correct); 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+; void decode(FILE *fp1,FILE *fp2) int Yinbuf,Uinbuf,Vinbuf; YinMCU
37、=sampleYH*sampleYV; UinMCU=sampleUH*sampleUV; VinMCU=sampleVH*sampleVV; HYtoU=sampleYH/sampleUH; VYtoU=sampleYV/sampleUV; HYtoV=sampleYH/sampleVH; VYtoV=sampleYV/sampleVV; Yinbuf=0;Uinbuf=YinMCU*64; Vinbuf=(YinMCU+UinMCU)*64; while(DecodeMCUBlock(fp1) interval+; if(restart)&(interval%restart=0) inte
38、rvalflag=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; if(width=0)&(h
