dct_jpeg.cpp

数据压缩课程设计的压缩编码实验题目,没有实际用处,只能用于演示变化过程.

#include<stdio.h>
#include<stdlib.h>
#include<math.h>
#define MX	8
const double PI=asin(1)*2.0;
int	*Addx=NULL;

struct MAT
{
	int row,col;
	double **pn;
};
/*************************/
bool	MulMatrix(MAT	a,MAT b,MAT &c)// a*b=c
{
	int i=0,j=0,k=0;
	double ex;
	if(a.col!=b.row){puts("error mul matrix (a,b): row != col");return false;}
	for(i=0;i<a.row;i++){
		for(j=0;j<b.col;j++){
			ex=0.0;
			for(k=0;k<a.col;k++){
				ex += a.pn[i][k] * b.pn[k][j];
			}
			c.pn[i][j]=ex; //printf("%8.3lf ",ex);
		}
		//puts("");
	}
	return true;
}
/*************************/
bool	PutMatrix(MAT a)
{
	int i,j;
	for(i=0;i<a.row;i++){
		for(j=0;j<a.col;j++){
			printf("%9.2lf",a.pn[i][j]);
		}
		printf("\n");
	}
	return true;
}
/*************************/
bool	GenMatrixA(MAT &a,MAT &at,int M)
{
	int i,j;
	double tmp=0.0;
	a.row=M;a.col=M;
	a.pn=(double**)malloc(sizeof(double*)*(a.row));
	at.row=M;at.col=M;
	at.pn=(double**)malloc(sizeof(double*)*(at.row));
	for(i=0;i<at.row;i++)at.pn[i]=(double*)malloc(sizeof(double)*(at.col));
	for(i=0;i<a.row;i++){
		a.pn[i]=(double*)malloc(sizeof(double)*(a.col));
		for(j=0;j<a.col;j++){
			if(i==0)a.pn[i][j]=sqrt(0.5);
			else a.pn[i][j]=1;
			a.pn[i][j]*=sqrt(2.0/M);
			tmp=PI;
			tmp=tmp * (2.0*j+1) * i / (2.0 * M);
			tmp=cos(tmp);
			a.pn[i][j]*=tmp;
			at.pn[j][i]=a.pn[i][j];
		}
	}
	return true;
}
bool	GenAddx(int n)
{
	int i,a=0,n2=n+n;
	Addx=(int*)malloc(sizeof(int)*(n2+1));
	Addx[0]=n2;
	for(i=1;i<=n;i++){
		Addx[i]=i*(i-1)/2;
	}
	for(;i<=n2;i++){
		Addx[i]=Addx[i-1]+n2-i+1;
	}
	return 0;
}

bool	ScanZZ(MAT a)
{
	int i,j,r,c,t;
	int Num=a.row * a.col;
	for(i=1;i<=Num;i++){
		for(j=Addx[0];j>=2;j--)if(Addx[j]<=i)break;
		r=i-Addx[j];
		c=j+(i-Addx[j]);
		if(j%2){
			t=r;r=c;c=t;
		}//odd number
	}
	return true;
}
///////////////////////////

int main()
{
	int i,j;
	FILE	*fp;
	MAT	a,at,b,c;
	fp=fopen("data.txt","rb");
	if(!fp){puts("Error open file");exit(0);}
	GenAddx(MX);
	for(i=0;i<=Addx[0];i++)printf("%d ",Addx[i]);puts("");
	GenMatrixA(a,at,MX);	
	//PutMatrix(a);puts("");

	fscanf(fp,"%d%d",&b.row,&b.col);
	b.pn=(double**)malloc(sizeof(double*)*(b.row));
	for(i=0;i<b.row;i++){
		b.pn[i]=(double*)malloc(sizeof(double)*(b.col));
		for(j=0;j<b.col;j++){
			fscanf(fp,"%lf",&b.pn[i][j]);
		}
	}
	//PutMatrix(b);puts("");

	c.row=a.row;
	c.col=b.col;
	c.pn=(double**)malloc(sizeof(double*)*(c.row));
	for(i=0;i<c.row;i++)c.pn[i]=(double*)malloc(sizeof(double)*(c.col));
	MulMatrix(a,b,c);
	MulMatrix(c,at,b);
	PutMatrix(b);


	return 0;
}