#include <u.h>#include <libc.h>#include <libg.h>#include <fb.h>int filter(unsigned char *);void map(PICFILE *, PICFILE *, int (*)(unsigned char *), int);main(int argc, char *argv[]){ PICFILE *in, *out; argc=getflags(argc, argv, ""); if(argc!=1 && argc!=2) usage("[picture]"); in=picopen_r(argc==2?argv[1]:"IN"); if(in==0){ perror(argc==2?argv[1]:"IN"); exits("open input"); } out=picopen_w("OUT", PIC_SAMEARGS(in)); if(out==0){ perror("OUT"); exits("creat output"); } map(in, out, filter, NWIN); exits(0);}#define new(t, n) ((t *)emalloc((n)*sizeof(t)))char *emalloc(int n){ char *v=malloc(n); if(v==0){ fprint(2, "Out of space\n"); exits("no space"); } return v;}struct line{ unsigned char *left; unsigned char *read; unsigned char *eread; unsigned char *right; unsigned char *cursor;};void getline(PICFILE *, struct line *, struct line *);void dupline(struct line *, struct line *);/* * Neighbourhood mapping from picture in to out. Each pixel of out * is written with some funcion of an n by n neighbourhood of in. * rou is called once for each channel of each output pixel. Its * argument is an n by n array of unsigned chars containing one channel * of the neighbourhood surrounding the corresponding input pixel. * Pixels on in's boundary are replicated to provide neighbours * for pixels close to the edge. * Should take a mask argument to indicate what channels to operate on. */void map(PICFILE *in, PICFILE *out, int (*rou)(unsigned char *), int n){ int j; unsigned char *p, *q; int nchan=PIC_NCHAN(in); int i; unsigned char *op, *eout, *buf, *box=new(unsigned char, n*n); unsigned char *outline=new(unsigned char, PIC_WIDTH(in)*nchan); int y; struct line *line, t; eout=outline+PIC_WIDTH(in)*nchan; line=new(struct line, n); line[0].left=buf=new(unsigned char, n*(PIC_WIDTH(in)+n-1)*nchan); for(i=0;i!=n;i++){ if(i) line[i].left=line[i-1].right; line[i].read=line[i].left+(n/2)*nchan; line[i].eread=line[i].read+PIC_WIDTH(in)*nchan; line[i].right=line[i].left+(PIC_WIDTH(in)+n-1)*nchan; } getline(in, &line[n/2], &line[n/2]); for(i=0;i!=n/2;i++) dupline(&line[i], &line[n/2]); for(i=n/2+1;i<n-1;i++) getline(in, &line[i], &line[i-1]); for(y=0;y!=PIC_WIDTH(in);y++){ getline(in, &line[n-1], &line[n-2]); for(i=0;i!=n;i++) line[i].cursor=line[i].left; for(op=outline;op!=eout;op++){ q=box; for(i=0;i!=n;i++){ p=line[i].cursor++; for(j=0;j!=n;j++){ *q++=*p; p+=nchan; } } *op=(*rou)(box); } picwrite(out, (char *)outline); t=line[0]; for(i=1;i!=n;i++) line[i-1]=line[i]; line[n-1]=t; } free((char *)box); free((char *)outline); free((char *)buf); free((char *)line);}/* * read a line from the input picture into the buffer described by lp, * replicating pixels at each end. if at eof, copy line mp. */void getline(PICFILE *f, struct line *lp, struct line *mp){ register unsigned char *p, *q; if(!picread(f, (char *)lp->read)) dupline(lp, mp); else{ p=lp->read; q=p+f->nchan; while(p!=lp->left) *--p = *--q; p=lp->eread; q=p-f->nchan; while(p!=lp->right) *p++ = *q++; }}/* * copy line mp into lp */void dupline(struct line *lp, struct line *mp){ memcpy((char *)lp->left, (char *)mp->left, mp->right-mp->left);}
#include <u.h>
#include <libc.h>
#include <libg.h>
#include <fb.h>
int filter(unsigned char *);
void map(PICFILE *, PICFILE *, int (*)(unsigned char *), int);
main(int argc, char *argv[]){
PICFILE *in, *out;
argc=getflags(argc, argv, "");
if(argc!=1 && argc!=2) usage("[picture]");
in=picopen_r(argc==2?argv[1]:"IN");
if(in==0){
perror(argc==2?argv[1]:"IN");
exits("open input");
}
out=picopen_w("OUT", PIC_SAMEARGS(in));
if(out==0){
perror("OUT");
exits("creat output");
}
map(in, out, filter, NWIN);
exits(0);
}
#define new(t, n) ((t *)emalloc((n)*sizeof(t)))
char *emalloc(int n){
char *v=malloc(n);
if(v==0){
fprint(2, "Out of space\n");
exits("no space");
}
return v;
}
struct line{
unsigned char *left;
unsigned char *read;
unsigned char *eread;
unsigned char *right;
unsigned char *cursor;
};
void getline(PICFILE *, struct line *, struct line *);
void dupline(struct line *, struct line *);
/*
* Neighbourhood mapping from picture in to out. Each pixel of out
* is written with some funcion of an n by n neighbourhood of in.
* rou is called once for each channel of each output pixel. Its
* argument is an n by n array of unsigned chars containing one channel
* of the neighbourhood surrounding the corresponding input pixel.
* Pixels on in's boundary are replicated to provide neighbours
* for pixels close to the edge.
* Should take a mask argument to indicate what channels to operate on.
*/
void map(PICFILE *in, PICFILE *out, int (*rou)(unsigned char *), int n){
int j;
unsigned char *p, *q;
int nchan=PIC_NCHAN(in);
int i;
unsigned char *op, *eout, *buf, *box=new(unsigned char, n*n);
unsigned char *outline=new(unsigned char, PIC_WIDTH(in)*nchan);
int y;
struct line *line, t;
eout=outline+PIC_WIDTH(in)*nchan;
line=new(struct line, n);
line[0].left=buf=new(unsigned char, n*(PIC_WIDTH(in)+n-1)*nchan);
for(i=0;i!=n;i++){
if(i) line[i].left=line[i-1].right;
line[i].read=line[i].left+(n/2)*nchan;
line[i].eread=line[i].read+PIC_WIDTH(in)*nchan;
line[i].right=line[i].left+(PIC_WIDTH(in)+n-1)*nchan;
}
getline(in, &line[n/2], &line[n/2]);
for(i=0;i!=n/2;i++) dupline(&line[i], &line[n/2]);
for(i=n/2+1;i<n-1;i++) getline(in, &line[i], &line[i-1]);
for(y=0;y!=PIC_WIDTH(in);y++){
getline(in, &line[n-1], &line[n-2]);
for(i=0;i!=n;i++) line[i].cursor=line[i].left;
for(op=outline;op!=eout;op++){
q=box;
for(i=0;i!=n;i++){
p=line[i].cursor++;
for(j=0;j!=n;j++){
*q++=*p;
p+=nchan;
}
}
*op=(*rou)(box);
}
picwrite(out, (char *)outline);
t=line[0];
for(i=1;i!=n;i++) line[i-1]=line[i];
line[n-1]=t;
}
free((char *)box);
free((char *)outline);
free((char *)buf);
free((char *)line);
}
/*
* read a line from the input picture into the buffer described by lp,
* replicating pixels at each end. if at eof, copy line mp.
*/
void getline(PICFILE *f, struct line *lp, struct line *mp){
register unsigned char *p, *q;
if(!picread(f, (char *)lp->read)) dupline(lp, mp);
else{
p=lp->read;
q=p+f->nchan;
while(p!=lp->left) *--p = *--q;
p=lp->eread;
q=p-f->nchan;
while(p!=lp->right) *p++ = *q++;
}
}
/*
* copy line mp into lp
*/
void dupline(struct line *lp, struct line *mp){
memcpy((char *)lp->left, (char *)mp->left, mp->right-mp->left);
}