/* * * DLWIC * * (c) Joonas Lehtinen (jole@jole.fi), TUCS, 1998 * */#include "gwic.h"/* Zerotree coding, decoding and stop condition *//* Continue scanning */int maxbytes;int stop_immediately;int cc() {  extern long BytesOutQM;     /* Number of bytes written at encoding stage */  if (!stop_immediately && maxbytes > BytesOutQM) {    code_bit(1,SCONT);    return 1;  } else {    if (stop_immediately) return 0;    code_bit(0,SCONT);    stop_immediately = 1;  }  return 0;}void scancode(U32 *coeff, int x, int y, heap2d *h, int n, int l,int fx,	  int fy,int lw,int lh){  int hv = *(*(h->lines + y)+x);  int state;  U32 *p;  U32 nthbit = 1 << (n-1);  int ch,cv,cd;  if (cc()) {    state = SNEWSIG + l;    if (l && (*(*(h->lines + fy)+fx) == n)) state += 16;    if (hv >= n) { /* There is something worth coding on this bitlevel n */      if (hv == n) 	code_bit(1,state);      if (l) {	/* Not on the top of pyramids */	p = h->width * y + coeff + x;	ch = *p; cd = *(p+lw); cv = *(p+lw-lh*h->width);		/* HORIZONTAL */	if ((ch&MASK) < (nthbit<<1)) {	  state  = SORISIGH + l;	  if ((cd&MASK) >= (nthbit<<1) || (cv&MASK) >= (nthbit<<1)) state +=16;	  code_bit((ch&MASK)>=nthbit?1:0,state);	  if ((ch&MASK) >= nthbit) {	    code_bit(ch&SIGN?1:0,SSIGN);	  }	} else 	  code_bit(ch&nthbit?1:0,SBIT);		/* DIAGONAL */	if ((cd&MASK) < (nthbit<<1)) {	  state  = SORISIGD + l;	  if ((ch&MASK) >= nthbit || (cv&MASK) >= (nthbit<<1)) state +=16;	  code_bit((cd&MASK)>=nthbit?1:0,state);	  if ((cd&MASK) >= nthbit) 	    code_bit(cd&SIGN?1:0,SSIGN);	} else 	  code_bit(cd&nthbit?1:0,SBIT);		/* VERTICAL */	if ((cv&MASK) < (nthbit<<1)) {	  state  = SORISIGV + l;	  if ((ch&MASK) >= nthbit || (cd&MASK) >= nthbit) state +=16;	  code_bit((cv&MASK)>=nthbit?1:0,state);	  if ((cv&MASK) >= nthbit) 	    code_bit(cv&SIGN?1:0,SSIGN);	} else 	  code_bit(cv&nthbit?1:0,SBIT);		if ((y<<1)<h->height) {	  scancode(coeff,x<<1,y<<1,h,n,l+1,x,y,lw<<1,lh<<1);	  scancode(coeff,(x<<1)+1,y<<1,h,n,l+1,x,y,lw<<1,lh<<1);	  scancode(coeff,x<<1,(y<<1)+1,h,n,l+1,x,y,lw<<1,lh<<1);	  scancode(coeff,(x<<1)+1,(y<<1)+1,h,n,l+1,x,y,lw<<1,lh<<1);	}      } else {	/* Top of the pyramids */	p = h->width * y + coeff + x;	ch = *p; 		if ((ch&MASK) < (nthbit<<1)) {	  code_bit((ch&MASK)>=nthbit?1:0,STOPLEVEL);	  if ((ch&MASK) >= nthbit) 	    code_bit(ch&SIGN?1:0,SSIGN);	} else 	  code_bit(ch&nthbit?1:0,SBIT);	scancode(coeff,x,y+lh,h,n,1,x,y,lw,lh);      }    } else code_bit(0,state);  }}/* Continue scanning */int cdc(){  if (stop_immediately) return 0;  if (!decode_bit(SCONT)) {    stop_immediately = 1;    return 0;  }  return 1;}void scandecode(U32 *coeff, int x, int y, heap2d *h, int n, 		int l,int fx, int fy,int lw,int lh){  int hv = *(*(h->lines + y)+x);  int state;  U32 *p;  U32 nthbit = 1 << (n-1);  int ch,cv,cd;  int ib=0;  if (cdc()) {    if (!hv) { /* There is something worth coding on this bitlevel n */      state = SNEWSIG + l;      if (l && (*(*(h->lines + fy)+fx) == n)) state += 16;      ib = decode_bit(state);    }    if (ib) hv = *(*(h->lines + y)+x) = n;    if (hv) {      /* Scan children */      if (l) {	p = h->width * y + coeff + x;	ch = *p; cd = *(p+lw); cv = *(p+lw-lh*h->width);	/* HORIZONTAL */	if (ch)	  *p = ch = (ch&(~nthbit)) | (decode_bit(SBIT) ? nthbit : 0) | (nthbit>>1);	else {	  state  = SORISIGH + l;	  if ((cd&MASK) >= (nthbit<<1) || (cv&MASK) >= (nthbit<<1)) state +=16;	  if (decode_bit(state)) 	    *p = ch = (decode_bit(SSIGN) ? SIGN : 0) | nthbit | (nthbit>>1);	}	/* DIAGONAL */	if (cd)	  *(p+lw) = cd = (cd&(~nthbit)) | (decode_bit(SBIT) ? nthbit : 0) | (nthbit>>1);	else {	  state  = SORISIGD + l;	  if ((ch&MASK) >= nthbit || (cv&MASK) >= (nthbit<<1)) state +=16;	  if(decode_bit(state)) 	    *(p+lw) = cd = (decode_bit(SSIGN) ? SIGN : 0) | nthbit | (nthbit>>1);	}	/* VERTICAL */	if (cv)	  *(p+lw-lh*h->width) = cv = (cv&(~nthbit)) | (decode_bit(SBIT) ? nthbit : 0) | (nthbit>>1);	else {	  state  = SORISIGV + l;	  if ((ch&MASK) >= nthbit || (cd&MASK) >= nthbit) state +=16;	  if(decode_bit(state)) 	    *(p+lw-lh*h->width) = cv = (decode_bit(SSIGN) ? SIGN : 0) | nthbit | (nthbit>>1);	}	if ((y<<1)<h->height) {	  scandecode(coeff,x<<1,y<<1,h,n,l+1,x,y,lw<<1,lh<<1);	  scandecode(coeff,(x<<1)+1,y<<1,h,n,l+1,x,y,lw<<1,lh<<1);	  scandecode(coeff,x<<1,(y<<1)+1,h,n,l+1,x,y,lw<<1,lh<<1);	  scandecode(coeff,(x<<1)+1,(y<<1)+1,h,n,l+1,x,y,lw<<1,lh<<1);	}      } else {	p = h->width * y + coeff + x;	ch = *p; 	/* TOPLEVEL */	if (ch)	  *p = ch = (ch&(~nthbit)) | (decode_bit(SBIT) ? nthbit : 0) | (nthbit>>1);	else 	  if(decode_bit(STOPLEVEL)) 	    *p = ch = (decode_bit(SSIGN) ? SIGN : 0) | nthbit | (nthbit>>1);    	scandecode(coeff,x,y+lh,h,n,1,x,y,lw,lh);      }    }   }}void zerotree_code(U32 *coeff, int width, int height, int levels, 		   int mbytes,  heap2d *heap, 		   int real_image_area){  int w,h,i,j,n;  stop_immediately = 0;  w = width >> levels;  h = height >> levels;  maxbytes = mbytes;    n = heap->max;  for(;n>0 && !stop_immediately; n--)     for (j=0; j<h && !stop_immediately; j++)       for (i=0; i<w && !stop_immediately; i++) 	scancode(coeff,i,j,heap,n,0,-1,-1,w,h);}U32 *zerotree_decode(int width, int height, int levels, int n){  U32 *coeff, *p;  int w,h,i,j;  heap2d *heap;  stop_immediately = 0;  MALLOC(coeff,width*height*sizeof(U32));    for(p=coeff, i=width*height; i; i--) *p++ = 0;  heap = gen_2d_heap(coeff, width, height, levels);    w = width >> levels;  h = height >> levels;    for(;n>0 && !stop_immediately; n--)     for (j=0; j<h && !stop_immediately; j++)       for (i=0; i<w && !stop_immediately; i++) 	scandecode(coeff,i,j,heap,n,0,-1,-1,w,h);  free(heap);    return coeff;}