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+/* tvgen - draw pm5544-like television test cards.
+ * Copyright (C) 2007, 2009, Servaas Vandenberghe.
+ *
+ * The tvgen code below is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with tvgen: see the file COPYING. If not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ * tvgen-1.1/tvgen.asy
+ * This asy script generates pm5544-like television test cards. The image
+ * parameters were derived from a 1990 recording. The basic parameters
+ * conform to itu-r bt.470, bt.601, and bt.709. There is no unique image
+ * since local variants exist and parameters have varied over time.
+ */
+//papertype="a4";
+import plain;
+int verbose=settings.verbose/*+2*/; /* uncomment for debug info */
+
+/* tv dot coordinates --> PS points */
+pair tvps(real col, real row, real xd, real yd, int Nv) {
+ real psx, psy;
+ psx=col*xd; psy=(Nv-row)*yd;
+ return (psx,psy);
+}
+path tvrect(int lc, int tr, int rc, int br, real xd, real yd, int Nv) {
+ real lx, ty, rx, by;
+ pair[] z;
+
+ lx=lc*xd; ty=(Nv-tr)*yd;
+ rx=rc*xd; by=(Nv-br)*yd;
+ /* bl br tr tl */
+ z[0]=(lx, by);
+ z[1]=(rx, by);
+ z[2]=(rx, ty);
+ z[3]=(lx, ty);
+
+ return z[0]--z[1]--z[2]--z[3]--cycle;
+}
+
+/********************* image aspect ratio markers ********************/
+void rimarkers(real rimage, int Nh, int Nhc, int os, int Nvc, int Nsy, pen pdef, real xd, real yd, int Nv) {
+ int[] ridefN={ 4, 16 };
+ int[] ridefD={ 3, 9 };
+ int i;
+
+ for(i=0; i<2; ++i) {
+ real rid=ridefN[i]/ridefD[i];
+
+ if(rimage>rid) {
+ int off, offa, offb;
+
+ /* Nhdef=Nh/rimage*rid */
+ off=round(Nh/rimage*rid/2);
+ offa=off+os;
+ offb=off-os;
+ // write(offa,offb);
+
+ if(2*offa<Nh) {
+ int hy, tr, br;
+ path zz;
+
+ hy=floor(Nsy/3);
+ tr=Nvc-hy;
+ br=Nvc+hy;
+
+ zz=tvrect(Nhc+offb, tr, Nhc+offa, br, xd,yd,Nv);
+ //dot(zz);
+ fill(zz, p=pdef);
+ zz=tvrect(Nhc-offa, tr, Nhc-offb, br, xd,yd,Nv);
+ fill(zz, p=pdef);
+ }
+ }
+ } /* for i */
+ return;
+}
+
+/************* cross hatch: line pairing, center interlace test *************/
+void centerline(int[] coff, int[] coffa, int[] coffb, int Nhc, int divsx,
+ int os, int[] rcrowc, int Nvc, int divsy,
+ pair ccenter, real[] rcoff, pair[] rcright, pair[] rcleft,
+ pen pdef, real xd, real yd, int Nv) {
+ pair[] z;
+ int col;
+ pen pblack=pdef+gray(0.0), pwhite=pdef+gray(1.0);
+
+ z[0]=rcright[divsy];
+
+ col=Nhc+coff[0];
+ z[1]=tvps(col,rcrowc[divsy], xd,yd,Nv);
+ z[2]=tvps(col,rcrowc[divsy-1], xd,yd,Nv);
+ col=Nhc-coff[0];
+ z[3]=tvps(col,rcrowc[divsy-1], xd,yd,Nv);
+ z[4]=tvps(col,rcrowc[divsy], xd,yd,Nv);
+
+ z[5]=rcleft[divsy];
+ z[6]=rcleft[divsy+1];
+
+ z[7]=tvps(col,rcrowc[divsy+1], xd,yd,Nv);
+ z[8]=tvps(col,rcrowc[divsy+2], xd,yd,Nv);
+ col=Nhc+coff[0];
+ z[9]=tvps(col,rcrowc[divsy+2], xd,yd,Nv);
+ z[10]=tvps(col,rcrowc[divsy+1], xd,yd,Nv);
+
+ z[11]=rcright[divsy+1];
+ fill(z[1]--z[2]--z[3]--z[4] //--z[5]--z[6]
+ --arc(ccenter, z[5], z[6])
+ --z[7]--z[8]--z[9]--z[10] //--z[11]--z[0]
+ --arc(ccenter,z[11], z[0])
+ --cycle, p=pblack);
+
+ int i, maxoff, rows, tr, br;
+ path zz;
+
+ maxoff=floor(rcoff[divsy]);
+
+ /* center cross: vertical and horizontal centerline */
+ rows=min(Nvc-rcrowc[divsy-1], rcrowc[divsy+2]-Nvc);
+ tr=Nvc-rows;
+ br=Nvc+rows;
+ //write("centerline long: rows tr br ", rows, tr, br);
+ zz=tvrect(Nhc-os, tr, Nhc+os, br, xd,yd,Nv);
+ fill(zz, p=pwhite);
+ zz=tvrect(Nhc-maxoff,Nvc-1, Nhc+maxoff,Nvc+1, xd,yd,Nv);
+ fill(zz, p=pwhite);
+
+ /* vertical short lines */
+ rows=min(Nvc-rcrowc[divsy], rcrowc[divsy+1]-Nvc);
+ tr=Nvc-rows;
+ br=Nvc+rows;
+ if(verbose>1)
+ write("centerline: rows tr br ", rows, tr, br);
+ for(i=0; i<=divsx; ++i) {
+ int off;
+
+ off=coff[i];
+ if(off<maxoff) {
+ int offa, offb;
+ path zzv;
+ offa=coffa[i];
+ offb=coffb[i];
+
+ zzv=tvrect(Nhc+offb, tr, Nhc+offa, br, xd,yd,Nv);
+ fill(zzv, p=pwhite);
+ zzv=tvrect(Nhc-offa, tr, Nhc-offb, br, xd,yd,Nv);
+ fill(zzv, p=pwhite);
+ }
+ }
+ return;
+}
+
+/************************ topbw **************************************/
+void topbw(int[] coff, int Nhc, int os, int urow, int trow, int brow,
+ pair ccenter, pair rclt, pair rclb, pair rcrt, pair rcrb,
+ pen pdef, real xd, real yd, int Nv) {
+ pen pblack=pdef+gray(0.0), pwhite=pdef+gray(1.0);
+ pair[] ze;
+ path zext, zref, zint;
+ int off, col, cr;
+
+ off=ceil((coff[2]+coff[3])/2);
+ ze[0]=tvps(Nhc+off,trow, xd,yd,Nv);
+ ze[1]=rcrt;
+ ze[2]=rclt;
+ ze[3]=tvps(Nhc-off,trow, xd,yd,Nv);
+ ze[4]=tvps(Nhc-off,brow, xd,yd,Nv);
+ col=Nhc-coff[2]-os;
+ ze[5]=tvps(col,brow, xd,yd,Nv);
+ ze[6]=tvps(col,trow, xd,yd,Nv);
+ cr=col+3*os; /* reflection test black pulse */
+ zref=tvrect(col,trow, cr,brow, xd,yd,Nv);
+ ze[7]=tvps(cr,trow, xd,yd,Nv);
+ ze[8]=tvps(cr,brow, xd,yd,Nv);
+ ze[9]=tvps(Nhc+off,brow, xd,yd,Nv);
+ //dot(ze);
+
+ zext=ze[0] // --ze[1]--ze[2]
+ --arc(ccenter, ze[1], ze[2])
+ --ze[3]--ze[4]--ze[5]--ze[6]--ze[7]--ze[8]--ze[9]--cycle;
+
+ off=ceil((coff[1]+coff[2])/2);
+ zint=tvrect(Nhc-off,urow, Nhc+off,trow, xd,yd,Nv);
+
+ /* paths are completely resolved; no free endpoint conditions */
+ fill(zext^^reverse(zint), p=pwhite);
+ fill(zint, p=pblack);
+ fill(zref, p=pblack);
+
+ fill(arc(ccenter,rclt,rclb)--ze[4]--ze[3]--cycle, p=pblack);
+ fill(arc(ccenter,rcrb,rcrt)--ze[0]--ze[9]--cycle, p=pblack);
+ return;
+}
+
+/************************ testtone **************************************/
+/* x on circle -> return y>=0
+ * in:
+ * x x-coordinate relative to origin
+ * crad circle radius in y units, true size=crad*yd
+ */
+real testcircx(real x, real crad, real xd, real yd) {
+ real relx, phi, y;
+
+ relx=x*xd/yd/crad;
+ if(relx>1) {
+ phi=0;
+ } else {
+ phi=acos(relx);
+ }
+ y=crad*sin(phi); // or (x*xd)^2+(y*yd)^2=(crad*yd)^2
+
+ return y;
+}
+/* y on circle -> return x>=0 */
+real testcircy(real y, real crad, real xd, real yd) {
+ real rely, phi, x;
+
+ rely=y/crad;
+ if(rely>1) {
+ phi=pi/2;
+ } else {
+ phi=asin(rely);
+ }
+ x=crad*cos(phi)*yd/xd; // or (x*xd)^2+(y*yd)^2=(crad*yd)^2
+
+ return x;
+}
+
+/* brow>trow && xb>xt */
+void testtone(real Tt, int trow, int brow,
+ real ccol, real crow, real crad,
+ pen pdef, real xd, real yd, int Nv) {
+ int blocks, i;
+ real yt, xt, yb, xb, Ttt=Tt/2;
+ pair ccenter;
+
+ yt=crow-trow;
+ xt=testcircy(yt, crad, xd, yd);
+ yb=crow-brow;
+ xb=testcircy(yb, crad, xd, yd);
+ //write('#xt yt\t',xt,yt); write('#xb yb\t',xb,yb);
+
+ ccenter=tvps(ccol,crow, xd,yd,Nv);
+
+ blocks=floor(2*xb/Tt);
+
+ for(i=-blocks-1; i<=blocks; ++i) {
+ real tl, tr;
+ path zz;
+
+ tl=max(-xb,min(i*Ttt,xb)); /* limit [-xb..xb] */
+ tr=max(-xb,min((i+1)*Ttt,xb));
+
+ if(tl<-xt && tr<=-xt || tr>xt && tl>=xt) { /* top full circle */
+ pair[] z;
+ real yl, yr;
+
+ yl=testcircx(tl, crad, xd, yd);
+ yr=testcircx(tr, crad, xd, yd);
+
+ z[0]=tvps(ccol+tl,brow, xd,yd,Nv);
+ z[1]=tvps(ccol+tr,brow, xd,yd,Nv);
+ z[2]=tvps(ccol+tr,crow-yr, xd,yd,Nv);
+ z[3]=tvps(ccol+tl,crow-yl, xd,yd,Nv);
+
+ zz=z[0]--z[1]--arc(ccenter,z[2],z[3])--cycle;
+ } else if(tl<-xt) { /* tl in circel, tr not, partial */
+ pair[] z;
+ real yl;
+
+ yl=testcircx(tl, crad, xd, yd);
+
+ z[0]=tvps(ccol+tl,brow, xd,yd,Nv);
+ z[1]=tvps(ccol+tr,brow, xd,yd,Nv);
+ z[2]=tvps(ccol+tr,trow, xd,yd,Nv);
+ z[3]=tvps(ccol-xt,trow, xd,yd,Nv);
+ z[4]=tvps(ccol+tl,crow-yl, xd,yd,Nv);
+
+ zz=z[0]--z[1]--z[2]--arc(ccenter,z[3],z[4])--cycle;
+ } else if(tr>xt) { /* tr in circle, tl not, partial */
+ pair[] z;
+ real yr;
+
+ yr=testcircx(tr, crad, xd, yd);
+
+ z[0]=tvps(ccol+tl,brow, xd,yd,Nv);
+ z[1]=tvps(ccol+tr,brow, xd,yd,Nv);
+ z[2]=tvps(ccol+tr,crow-yr, xd,yd,Nv);
+ z[3]=tvps(ccol+xt,trow, xd,yd,Nv);
+ z[4]=tvps(ccol+tl,trow, xd,yd,Nv);
+ zz=z[0]--z[1]--arc(ccenter,z[2],z[3])--z[4]--cycle;
+ } else { /* full block */
+ pair[] z;
+
+ z[0]=tvps(ccol+tr,trow, xd,yd,Nv);
+ z[1]=tvps(ccol+tl,trow, xd,yd,Nv);
+ z[2]=tvps(ccol+tl,brow, xd,yd,Nv);
+ z[3]=tvps(ccol+tr,brow, xd,yd,Nv);
+ zz=z[0]--z[1]--z[2]--z[3]--cycle;
+ }
+
+ if(tl<tr) {
+ if(i%2 == 0) {
+ fill(zz, p=pdef+gray(0.0));
+ } else {
+ fill(zz, p=pdef+gray(0.75));
+ }
+ }
+ }
+ return;
+}
+
+/************************ color bars *************************************/
+void colorbars(int[] coff, int Nhc, int trow, int crow, int brow,
+ pair ccenter, pair rclt, pair rclb, pair rcrt, pair rcrb,
+ pen pdef, real xd, real yd, int Nv) {
+ real cI=0.75;
+ real[] cR={ cI, 0, 0, cI, cI, 0 };
+ real[] cG={ cI, cI, cI, 0, 0, 0 };
+ real[] cB={ 0, cI, 0, cI, 0, cI };
+ int cmax=2, poff, rows, i;
+
+ rows=brow-trow;
+ poff=0;
+ for(i=0; i<=cmax; ++i) {
+ int off;
+ int ii=2*i, il=cmax-i, ir=i+cmax+1;
+ path zzl, zzr;
+
+ off=ceil((coff[1+ii]+coff[2+ii])/2);
+ if(i!=0 && i<cmax) {
+ zzr=tvrect(Nhc+poff,trow, Nhc+off,brow, xd,yd,Nv);
+ zzl=tvrect(Nhc-off,trow, Nhc-poff,brow, xd,yd,Nv);
+ } else {
+ if(i==0) {
+ int col, pcol;
+ pair[] zl, zr;
+
+ col=Nhc+off;
+ pcol=Nhc+poff;
+ zr[0]=tvps(col,trow, xd,yd,Nv);
+ zr[1]=tvps(pcol,trow, xd,yd,Nv);
+ zr[2]=tvps(pcol,crow, xd,yd,Nv);
+ zr[3]=tvps(Nhc+coff[0],crow, xd,yd,Nv);
+ zr[4]=tvps(Nhc+coff[0],brow, xd,yd,Nv);
+ zr[5]=tvps(col,brow, xd,yd,Nv);
+ zzr=zr[0]--zr[1]--zr[2]--zr[3]--zr[4]--zr[5]--cycle;
+
+ col=Nhc-off;
+ pcol=Nhc-poff;
+ zl[0]=tvps(pcol,trow, xd,yd,Nv);
+ zl[1]=tvps(col,trow, xd,yd,Nv);
+ zl[2]=tvps(col,brow, xd,yd,Nv);
+ zl[3]=tvps(Nhc-coff[0],brow, xd,yd,Nv);
+ zl[4]=tvps(Nhc-coff[0],crow, xd,yd,Nv);
+ zl[5]=tvps(pcol,crow, xd,yd,Nv);
+ zzl=zl[0]--zl[1]--zl[2]--zl[3]--zl[4]--zl[5]--cycle;
+ } else {
+ int pcol;
+ pair[] zl, zr;
+
+ pcol=Nhc+poff;
+ zr[0]=tvps(pcol,brow, xd,yd,Nv);
+ zr[1]=rcrb;
+ zr[2]=rcrt;
+ zr[3]=tvps(pcol,trow, xd,yd,Nv);
+ zzr=zr[0]--arc(ccenter,zr[1],zr[2])--zr[3]--cycle;
+
+ pcol=Nhc-poff;
+ zl[0]=tvps(pcol,trow, xd,yd,Nv);
+ zl[1]=rclt;
+ zl[2]=rclb;
+ zl[3]=tvps(pcol,brow, xd,yd,Nv);
+ zzl=zl[0]--arc(ccenter,zl[1],zl[2])--zl[3]--cycle;
+ }
+ }
+ fill(zzr, p=pdef+rgb(cR[ir], cG[ir], cB[ir]));
+ fill(zzl, p=pdef+rgb(cR[il], cG[il], cB[il]));
+
+ poff=off;
+ }
+ return;
+}
+
+/************************ test frequencies ****************************/
+/* in
+ * theta rad
+ * freq 1/hdot
+ * step hdot
+ * out
+ * new phase theta
+ */
+real addphase(real theta, real freq, real step) {
+ real cycles, thetaret;
+ int coverflow;
+
+ cycles=freq*step;
+ coverflow=floor(abs(cycles));
+ if(coverflow>1) {
+ thetaret=0;
+ } else {
+ real dpi=2*pi;
+
+ cycles-=coverflow*sgn(cycles);
+ thetaret=theta+cycles*dpi; /* cycles=(-1 .. 1) */
+
+ if(thetaret>pi) {
+ thetaret-=dpi;
+ } else if(thetaret<-pi) {
+ thetaret-=dpi;
+ }
+ }
+
+ //write("addphase: ", step, theta, thetaret);
+ return thetaret;
+}
+
+void testfreqs(real[] ftones, int[] coff, int Nhc, int trow,int crow,int brow,
+ pair ccenter, pair rclt, pair rclb, pair rcrt, pair rcrb,
+ pen pdef, real xd, real yd, int Nv) {
+ int[] divc;
+ real[] divfl, divfr;
+ int i, divs, coffmax, off, divnext;
+ real fl, fr, thr, thl;
+
+ /* Segment info for PAL continental test card
+ * segment i extends from [divc[i] .. divc[i+1]) with frequency divf[i]
+ */
+ divs=2; // the number of segments on the right, total=2*divs+1
+ divc[0]=0;
+ for(i=0; i<=divs; ++i) {
+ int ii=i*2, il=divs-i, ir=divs+i;
+
+ divc[i+1]=ceil((coff[ii]+coff[ii+1])/2); /* xdot distance to center */
+
+ divfl[i]=ftones[divs-i];
+ divfr[i]=ftones[divs+i];
+ }
+ coffmax=divc[divs+1];
+
+ int trowlim=coff[0];
+ int tr;
+
+ tr=crow;
+
+ divnext=0;
+ fl=0;
+ fr=0;
+ thl=0;
+ thr=0;
+ // draw a vertical line at off..off+1
+ for(off=0; off<coffmax; ++off) {
+ real ampl, ampr;
+ int col;
+ path zz;
+
+ if(off==trowlim) {
+ tr=trow;
+ }
+
+ if(off == divc[divnext]) {
+ /* switch frequency: cycles=0.5*fcur+0.5*fnext */
+ thl=addphase(thl, fl, -0.5);
+ thr=addphase(thr, fr, 0.5);
+ fl=divfl[divnext];
+ fr=divfr[divnext];
+ thl=addphase(thl, fl, -0.5);
+ thr=addphase(thr, fr, 0.5);
+
+ ++divnext;
+ // thl=pi; thr=pi;
+ //write(off, fl, fr);
+ } else {
+ thl=addphase(thl, fl, -1);
+ thr=addphase(thr, fr, 1);
+ // thl=0; thr=0;
+ }
+
+ ampl=(1+sin(thl))/2;
+ ampr=(1+sin(thr))/2;
+ //write(off, thr, ampr);
+
+ col=Nhc-off-1;
+ zz=tvrect(col,tr, col+1,brow, xd,yd,Nv);
+ fill(zz, p=pdef+gray(ampl));
+ col=Nhc+off;
+ zz=tvrect(col,tr, col+1,brow, xd,yd,Nv);
+ fill(zz, p=pdef+gray(ampr));
+ }
+
+ pair[] z;
+ z[0]=tvps(Nhc-coffmax,trow, xd,yd,Nv);
+ z[1]=tvps(Nhc-coffmax,brow, xd,yd,Nv);
+ fill(z[0]--arc(ccenter,rclt,rclb)--z[1]--cycle, p=pdef+gray(0.0));
+ z[0]=tvps(Nhc+coffmax,brow, xd,yd,Nv);
+ z[1]=tvps(Nhc+coffmax,trow, xd,yd,Nv);
+ fill(z[0]--arc(ccenter,rcrb,rcrt)--z[1]--cycle, p=pdef+gray(0.0));
+ return;
+}
+
+/************************ gray bars **************************************/
+void graybars(int[] coff, int Nhc, int trow, int brow,
+ pair ccenter, pair rclt, pair rclb, pair rcrt, pair rcrb,
+ pen pdef, real xd, real yd, int Nv) {
+ int[] gs={0, 51, 102, 153, 204, 255};
+ int cmax=2, poff, rows, i;
+
+ rows=brow-trow;
+ poff=0;
+ for(i=0; i<=cmax; ++i) {
+ int off;
+ int ii=2*i, il=cmax-i, ir=i+cmax+1;
+ path zzl, zzr;
+
+ off=ceil((coff[1+ii]+coff[2+ii])/2);
+ if(i<cmax) {
+ zzl=tvrect(Nhc-off,trow, Nhc-poff,brow, xd,yd,Nv);
+ zzr=tvrect(Nhc+poff,trow, Nhc+off,brow, xd,yd,Nv);
+ } else {
+ int pcol;
+ pair zlt, zlb, zrt, zrb;
+
+ pcol=Nhc-poff;
+ zlt=tvps(pcol,trow, xd,yd,Nv);
+ zlb=tvps(pcol,brow, xd,yd,Nv);
+ zzl=zlt--arc(ccenter,rclt,rclb)--zlb--cycle;
+
+ pcol=Nhc+poff;
+ zrb=tvps(pcol,brow, xd,yd,Nv);
+ zrt=tvps(pcol,trow, xd,yd,Nv);
+ zzr=zrb--arc(ccenter,rcrb,rcrt)--zrt--cycle;
+ }
+ fill(zzl, p=pdef+gray(gs[il]/255));
+ fill(zzr, p=pdef+gray(gs[ir]/255));
+
+ poff=off;
+ }
+ return;
+}
+
+/************************ bottom bw **************************************/
+void bottombw(int off, int Nhc, int trow, int brow,
+ pair ccenter, pair rclt, pair rclb, pair rcrt, pair rcrb,
+ pen pdef, real xd, real yd, int Nv) {
+ int rows;
+ pair zt, zb;
+ path zz;
+
+ rows=brow-trow;
+ zz=tvrect(Nhc-off,trow, Nhc+off,brow, xd,yd,Nv);
+ fill(zz, p=pdef+gray(0.0));
+
+ zt=tvps(Nhc-off,trow, xd,yd,Nv);
+ zb=tvps(Nhc-off,brow, xd,yd,Nv);
+ fill(zt--arc(ccenter,rclt,rclb)--zb--cycle, p=pdef+gray(1.0));
+
+ zb=tvps(Nhc+off,brow, xd,yd,Nv);
+ zt=tvps(Nhc+off,trow, xd,yd,Nv);
+ fill(zb--arc(ccenter,rcrb,rcrt)--zt--cycle, p=pdef+gray(1.0));
+ return;
+}
+
+/************************ bottom circle **************************************/
+void bottomcirc(int off, int Nhc, int trow, real cx, real cy, real crad,
+ pair ccenter, pair rclt, pair rcrt,
+ pen pdef, real xd, real yd, int Nv) {
+ real cI=0.75;
+ real xl, yl, xr, yr, phil, phir;
+ pair ccleft, ccright;
+ pair[] z;
+
+ xl=Nhc-off-cx;
+ phil=acos(xl*xd/yd/crad);
+ yl=crad*sin(phil); // or (x*xd)^2+(y*yd)^2=(crad*yd)^2
+ ccleft=tvps(cx+xl,cy+yl, xd,yd,Nv);
+ //write(xl,yl);
+
+ xr=Nhc+off-cx;
+ phir=acos(xr*xd/yd/crad);
+ yr=crad*sin(phir);
+ ccright=tvps(cx+xr,cy+yr, xd,yd,Nv);
+
+ //dot(ccright); dot(ccleft);
+ // red center
+ z[0]=tvps(Nhc-off,trow, xd,yd,Nv);
+ z[1]=ccleft;
+ z[2]=ccright;
+ z[3]=tvps(Nhc+off,trow, xd,yd,Nv);
+ fill(z[0]--arc(ccenter,z[1],z[2])--z[3]--cycle, p=pdef+rgb(cI,0,0));
+
+ // yellow
+ z[0]=tvps(Nhc-off,trow, xd,yd,Nv);
+ z[1]=rclt;
+ z[2]=ccleft;
+ fill(z[0]--arc(ccenter,z[1],z[2])--cycle, p=pdef+rgb(cI,cI,0));
+ z[0]=tvps(Nhc+off,trow, xd,yd,Nv);
+ z[1]=ccright;
+ z[2]=rcrt;
+ fill(z[0]--arc(ccenter,z[1],z[2])--cycle, p=pdef+rgb(cI,cI,0));
+
+ return;
+}
+
+/****************************** PAL ears ***********************************
+ * left y R G B
+ * 0.55 98 162 140
+ * 0.5 103 128 191
+ * 0.5 152 128 64
+ * 0.45 157 93 115
+ * right
+ * 0.6 153 168 76
+ * 0.4 102 87 179
+ *
+ * in: dright= -1 left ear, +1 right ear
+ */
+void palears(int[] coff, int[] coffa, int[] coffb, int Nhc,
+ int[] rcrowt, int[] rcrowb, int Nvc, int divsy, int dright,
+ pen pdef, real xd, real yd, int Nv) {
+ /* the amplitude of (u,v) as seen on a vectorscope,
+ * max 0.296 Vn for 100% saturation in W and V ears.
+ * cvbs: 0.7*( y +/- |u+jv| ) = -0.24 .. 0.93 V
+ * maxima: ebu 75/0 bars 0.70, bbc 100/25 0.88, 100/0 bars 0.93
+ * burst: 0.150 Vcvbs, 21.4 IRE or 0.214 V normalized.
+ * luma: modulated for monochrome compatibility, 1990 version.
+ * choice: set amplitude of subcarrier equal to amplitude of colorburst.
+ */
+ real cI=0.214;
+
+ /* (u,v) for zero G-y, phase of -34.5 degrees */
+ real wr=0.299, wb=0.114, wg=1-wr-wb; /* wg=0.587, y=wr*R+wg*G+wb*B */
+ real wu=0.493, wv=0.877; /* u=wu*(B-y) v=wv*(R-y) */
+ real colu=wu*wg/wb, colv=-wv*wg/wr; /* for w=(G-y)/0.696 == 0 */
+
+ /* ears: U==0 W==0 W==0 U==0 */
+ real[] cyl={ 0.55, 0.5, 0.5, 0.45 };
+ real[] cul={ 0, colu, -colu, 0 };
+ real[] cvl={ -1, colv, -colv, 1 };
+
+ /* ears: V==0 W==0 W==0 V==0 */
+ real[] cyr={ 0.60, 0.5, 0.5, 0.40 };
+ real[] cur={ -1, colu, -colu, 1 };
+ real[] cvr={ 0, colv, -colv, 0 };
+
+ real[] cy, cu, cv;
+ pair[] z;
+ path[] zz;
+ int lcol, ccol, cicol, rcol, i;
+
+ if(dright>0) {
+ cy=cyr; cu=cur; cv=cvr;
+ } else {
+ cy=cyl; cu=cul; cv=cvl;
+ }
+
+ lcol=Nhc+dright*coffa[5];
+ ccol=Nhc+dright*coff[6];
+ cicol=Nhc+dright*coffa[6];
+ rcol=Nhc+dright*coffb[7];
+
+ int urow, trow, crow, brow, arow;
+ urow=rcrowb[divsy-5];
+ trow=rcrowt[divsy-3];
+ crow=Nvc;
+ brow=rcrowb[divsy+4];
+ arow=rcrowt[divsy+6];
+
+ z[0]=tvps(ccol,urow, xd,yd,Nv);
+ z[1]=tvps(ccol,trow, xd,yd,Nv);
+ z[2]=tvps(cicol,trow, xd,yd,Nv);
+ z[3]=tvps(cicol,crow, xd,yd,Nv);
+ z[4]=tvps(rcol,crow, xd,yd,Nv);
+ z[5]=tvps(rcol,urow, xd,yd,Nv);
+ zz[0]=z[0]--z[1]--z[2]--z[3]--z[4]--z[5]--cycle;
+
+ zz[1]=tvrect(lcol,urow, ccol,trow, xd,yd,Nv);
+ zz[2]=tvrect(lcol,brow, ccol,arow, xd,yd,Nv);
+
+ z[0]=tvps(ccol,arow, xd,yd,Nv);
+ z[1]=tvps(ccol,brow, xd,yd,Nv);
+ z[2]=tvps(cicol,brow, xd,yd,Nv);
+ z[3]=tvps(cicol,crow, xd,yd,Nv);
+ z[4]=tvps(rcol,crow, xd,yd,Nv);
+ z[5]=tvps(rcol,arow, xd,yd,Nv);
+ zz[3]=z[0]--z[1]--z[2]--z[3]--z[4]--z[5]--cycle;
+
+ for(i=0; i<4; ++i) {
+ real y, u, v, A, ph, By, Ry, Gy, R, G, B;
+
+ y=cy[i];
+ u=cu[i];
+ v=cv[i];
+
+ A=hypot(u,v);
+ ph= (u!=0 || v!=0) ? atan2(v,u) : 0.0;
+ if(v>=0) {
+ if(ph<0) ph=ph+pi;
+ } else {
+ if(ph>0) ph=ph-pi;
+ }
+ if(A>0) {
+ u=u/A*cI;
+ v=v/A*cI;
+ }
+
+ By=u/wu;
+ Ry=v/wv;
+ Gy=(-wr*Ry-wb*By)/wg;
+ //write(y,Gy,A,ph*180/pi);
+
+ R=Ry+y;
+ G=Gy+y;
+ B=By+y;
+ if(verbose > 1)
+ write(y,round(R*255),round(G*255),round(B*255));
+
+ fill(zz[i], p=pdef+rgb(R,G,B));
+ }
+ return;
+}
+
+/****************************** NTSC bars ***********************************
+ * amplitude equals color burst smpte (pm: -V +U)
+ * y campl sat R G B
+ * left 0.5 0.21 70% -I?
+ * right 0.5 0.17 60% +Q?
+ */
+void ntscbars(int[] coff, int[] coffa, int[] coffb, int Nhc,
+ int[] rcrowt, int[] rcrowb, int Nvc, int divsy, int dright,
+ pen pdef, real xd, real yd, int Nv) {
+ /* The amplitude of (i,q) as seen on a vectorscope,
+ * max 0.292 Vn for 100% saturation in I==0 ears.
+ * burst: 0.143 Vcvbs, 20 IRE or 0.200 V normalized.
+ * pedestal: (yp,up,vp)=(p,0,0)+(1-p)*(y,u,v), p=0.075.
+ * choice: equal amplitude for colorburst and subcarrier.
+ */
+ real campl=0.200/0.925;
+
+ /* wg=0.587, y=wr*R+wg*G+wb*B */
+ real wr=0.299, wb=0.114, wg=1-wr-wb;
+ /* iT : iq -> RyBy : rotation+scaling */
+ real iT11=0.95, iT12=0.62, iT21=-1.11, iT22=1.71;
+
+ /* bars -2 -1 0 1 2 */
+ real[] cyl={ 0.50, 0.50, 0, 0.50, 0.50 };
+ real[] cil={ 0, 0, 0, -1, 1 };
+ real[] cql={ -1, 1, 0, 0, 0 };
+ int[] offil={ 6, 7, 5, 7, 6 };
+
+ real cy, ci, cq;
+ int dri, dris, offi, lcol, rcol, i;
+
+ if(dright>=0) {
+ dris=1;
+ } else {
+ dris=-1;
+ }
+ if(dright<-2 || dright>2) {
+ dri=2;
+ } else {
+ dri=2+dright;
+ }
+
+ cy=cyl[dri]; ci=cil[dri]; cq=cql[dri];
+ offi=offil[dri];
+ lcol=Nhc+dris*coffa[offi];
+ rcol=Nhc+dris*coffb[offi+1];
+
+ real A, By, Ry, Gy, R, G, B;
+
+ A=hypot(ci,cq);
+ if(A>0) {
+ ci=ci/A*campl;
+ cq=cq/A*campl;
+ }
+ Ry=iT11*ci+iT12*cq;
+ By=iT21*ci+iT22*cq;
+ Gy=(-wr*Ry-wb*By)/wg;
+ //write(cy,Ry,Gy,By);
+
+ R=Ry+cy;
+ G=Gy+cy;
+ B=By+cy;
+ if(verbose > 1)
+ write(cy,ci,cq,round(R*255),round(G*255),round(B*255));
+
+ for(i=-divsy; i<=divsy; ++i) {
+ path zz;
+ int brow, trow;
+
+ if(i>-divsy) {
+ trow=rcrowb[divsy+i];
+ } else {
+ trow=floor((rcrowb[divsy+i]+rcrowt[divsy+i+1])/2);
+ }
+
+ if(divsy>i) {
+ brow=rcrowt[divsy+i+1];
+ } else {
+ brow=floor((rcrowb[divsy+i]+rcrowt[divsy+i+1])/2);
+ }
+
+ zz=tvrect(lcol,brow, rcol,trow, xd,yd,Nv);
+ fill(zz, p=pdef+rgb(R,G,B));
+ }
+
+ return;
+}
+
+
+/****************************** main ***********************************/
+/* Conversion to bitmap:
+ * EPSPNG='gs -dQUIET -dNOPAUSE -dBATCH -sDEVICE=png16m'
+ * asy -u bsys=2 -u colortv=1 -u os=1 -a Z tvgen
+ * $EPSPNG -r132x144 -g720x576 -sOutputFile=tvgen.png tvgen.eps
+ *
+ * asy -u bsys=2 -u colortv=1 -u os=1 tvgen
+ */
+int bsys=2, colortv=1, os=1;
+
+/* bsys: broadcast system
+ * bsys im aspect Nh
+ * 0 4/3 704 guaranteed analog broadcast itu-r bt.470
+ * 1 4/3 720 new broadcast, most TV station logos and animations
+ * 2 15/11 720 total aperture analog 4/3, 1.37 film DVDs
+ * 3 20/11 720 total aperture analog 16/9, 1.85 film DVDs
+ * 4 4/3 768 bsys=0, square dot analog broadcast
+ * 5 4/3 768 bsys=1, square dot cable TV info channel
+ * 6 131/96 786 bsys=2, total square dot broadcast camera
+ * 7 16/9 720 new broadcast 16/9, SD from HD-1440 or itu-r bt.709
+ * 8 4/3 704 525 analog broadcast itu-r bt.470 711*485
+ * 9 4/3 720 525 new broadcast
+ * 10 15/11 720 525 total aperture analog broadcast
+ * 11 16/9 1920 1250, 1080 square dot at 12.5 frames/second
+ * 12 4/3 1600 1250, 1200 square dot at 12.5 frames/second
+ *
+ * colortv:
+ * set 0 for monochrome crosshatch, 1 for pal ears, 2 for ntsc bars
+ *
+ * os: horizontal oversampling, typical values for 13.5MHz:
+ * 2 4/3 704*576, 15/11 720*576
+ * 4 4/3 720*480
+ * 5 4/3 704*480, 15/11 720*480, 4/3 768*576 14.4MHz
+ * 8 4/3 720*576, 20/11 720*576
+ * 12 704->768 rerastering
+ * 16 720->768 rerastering
+ */
+access settings;
+usersetting();
+
+if(bsys<0 || bsys>12 || colortv<0 || colortv>3 || os<=0 || os>16) {
+ write('Error: bad user input: bsys, colortv, os=\t', bsys, colortv, os);
+ abort('Bad option -u bsys=N ?');
+}
+
+int[] bNdot=
+ { 12, 16, 12, 16, 1, 1, 1, 64, 10, 8, 10, 1, 1 };
+int[] bDdot=
+ { 11, 15, 11, 11, 1, 1, 1, 45, 11, 9, 11, 1, 1 };
+int[] bNh=
+ { 704, 720, 720, 720, 768, 768, 786, 720, 704, 720, 720, 1920, 1600 };
+int[] bNv=
+ { 576, 576, 576, 576, 576, 576, 576, 576, 480, 480, 480, 1080, 1200 };
+real[] bfs=
+ { 13.5,13.5,13.5,13.5, 14.75,14.4,14.75,13.5, 13.5,13.5,13.5, 36, 30 };
+int[] bNsy=
+ { 42, 42, 42, 42, 42, 42, 42, 42, 34, 34, 34, 78, 90 };
+int[] bNsh=
+ { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+
+/* active lines for a 625 line frame
+ * The number of active video lines decreased around 1997.
+ * old: 3 run in + 575 visible + 3 run out = 581 lines
+ * new: 6 teletext and WSS + 575 visible
+ * Hence the image center shifted down by 3 lines. Thus
+ * old TV + new testcard = bottom is cut off,
+ * new TV + old testcard = top is cut off.
+ *
+ * To generate the old testcard either use Nv=582 Nsh=0 or Nv=576 Nsh=3.
+ *
+ * aspect ratio
+ * rimage=xsize/ysize rimage=rdot*Nh/Nv
+ * Nh=704 dots
+ * Nv=576 lines
+ * rd=ri*Nv/Nh=4/3*9/11=12/11
+ *
+ * Nv: 480=2^5*3*5 576=2^6*3^2
+ * Nh: 704=2^6*11 720=2^4*3^2*5
+ *
+ * horizontal line distance for pre 1997 test pattern
+ * top 8 lines, 13 squares of Ny=43 lines, bottom 9 lines
+ * top 12 lines, 13 squares of Ny=42 lines, bottom 18 lines
+ * pairs are from odd even field
+ * Interlace test: Ny must be odd for a cross-hatch without centerline.
+ *
+ * squares: ly=Nsy, lx=rd*Nsx, lx=ly ==> Nsx=Nsy/rd={ 39.4, 38.5 }
+ * x line width 230 ns -> 3 dots
+ * bottom 2.9us red -> 39.15 dots
+ *
+ * resolution DPI from image aspect ratio
+ * Rv=Nv/ly, ly=4in
+ * ri=Ni/Di, Ni={4,15,16} Di={3,11,9}
+ * lx=ri*ly
+ *
+ * Rh=Nh/lx=Di*(Nh/(Ni*ly))
+ * ==> ri=4/Di => Nh=k*16
+ * ri=15/Di => Nh=k*60
+ * ri=16/Di => Nh=k*64
+ *
+ * resolution DPI from dot aspect ratio, general algorithm,
+ *
+ * rd=Nd/Dd=ldx/ldy
+ *
+ * assume 1 dot = Nd x Dd square subdots at a resolution of k, in dpi, then
+ *
+ * ldx=Nd/k, ldy=Dd/k ==> Rh=k/Nd, Rv=k/Dd
+ *
+ * choosing k=m*Nd*Dd for integer Rh and Rv gives
+ *
+ * ldx=1/(m*Dd), ldy=1/(m*Nd), Rh=m*Dd, Rv=m*Nd
+ *
+ * and
+ *
+ * lx=Nh*ldx=Nh/(m*Dd), ly=Nv*ldy=Nv/(m*Nd)
+ *
+ * so choose m for the intended height Ly, in inch, as
+ *
+ * m=round(Nv/(Ly*Nd))
+ *
+ * which limits Ly<=Nv/Nd since Rv>=Nd.
+ */
+//cm=72/2.540005;
+real Ly, ly, lx, ysize, xsize, rimage, xd, yd, pwidth;
+int Nd, Dd, m, Nh, Nv, Nshift, Na, Nsy;
+real fs, Ttone;
+
+Nd=bNdot[bsys];
+Dd=bDdot[bsys]*os;
+Nh=bNh[bsys]*os;
+Nv=bNv[bsys];
+
+Ly=4; // 4 inch vertical size
+m=floor(0.5+Nv/(Ly*Nd));
+if(m<1) m=1;
+ly=Nv/(m*Nd);
+lx=Nh/(m*Dd);
+
+ysize=ly*1inch;
+xsize=lx*1inch;
+rimage=xsize/ysize;
+if(verbose > 1)
+ write('#Nd Dd m ri:\t', Nd, Dd, m, rimage);
+//size(xsize,ysize,Aspect); // should not have any effect
+
+Nsy=bNsy[bsys]; // grating size in lines 42,43, 34,35
+Nshift=bNsh[bsys]; // shift image up: pre 1997 =3, 2007 =0
+fs=1e6*bfs[bsys]*os;
+Na=0; // add 1,0,-1 to height of hor center squares for even Na+Nsy
+
+Ttone=fs/250e3; // period of ft=250 kHz, fs/ft=54
+real[] ftones={0.8e6/fs, 1.8e6/fs, 2.8e6/fs, 3.8e6/fs, 4.8e6/fs};
+
+xd=xsize/Nh;
+yd=ysize/Nv;
+pwidth=min(abs(xd),abs(yd));
+
+pen pdefault=squarecap+linewidth(pwidth);
+pen pblack=pdefault+gray(0.0);
+pen pwhite=pdefault+gray(1.0);
+
+/**** calculate grating repeats and size in tv dots ****/
+// horizontal lines
+int divsy, rdisty, Nvc, Nt, Nb;
+
+Nvc=floor(Nv/2)-Nshift;
+divsy=floor(((Nv-Na-2)/Nsy-1)/2); // (Nv-Na-2)/2-Nsy/2 dots for Nsy lengths
+rdisty=Na+Nsy*(1+2*divsy);
+Nt=Nvc-ceil(rdisty/2);
+Nb=Nv-Nt-rdisty;
+if(verbose > 1)
+ write('#divsy t b: \t',divsy,Nt,Nb);
+
+/* Nsyc: center square height
+ * line pairing test: verify distance of center to top and bot
+ * distance is odd ==> top=even/odd, cent=odd/even, bot=even/odd
+ *
+ * Nsyc odd: not possible
+ *
+ * Nsyc even:
+ * Nsyc/2 odd --> OK
+ * Nsyc/2 even --> stagger the raster one line upwards
+ *
+ * rcrowt top dist of hor line
+ * rcrowc true center for color info, distance to top of image.
+ * rcrowb bot dist of hor line
+ *
+ * Nt=Nvc-(offu+divsy*Nsy);
+ * Nb=Nv-( Nvc-(offd-divsy*Nsy) );
+ * ==> Nt+Nb=Nv-Nsyc-2*divsy*Nsy
+ */
+int Nsyc, offu, offd, Nyst=0, i;
+int[] rcrowt, rcrowc, rcrowb;
+
+Nsyc=Nsy+Na;
+offu=floor(Nsyc/2);
+offd=offu-Nsyc;
+if(Nsyc%2 != 0) {
+ Nyst=1;
+} else if(Nsyc%4 == 0) {
+ Nyst=1; /* stagger */
+}
+for(i=0; i<=divsy; ++i) {
+ int iu, id, ou, od, ru, rd;
+
+ iu=divsy-i;
+ id=divsy+i+1;
+
+ ou=offu+Nsy*i;
+ od=offd-Nsy*i;
+ if(verbose > 1)
+ write(ou,od);
+ rcrowc[iu]=Nvc-ou;
+ rcrowc[id]=Nvc-od;
+
+ ru=Nvc-(ou+Nyst);
+ rd=Nvc-(od+Nyst);
+
+ rcrowt[iu]=ru-1;
+ rcrowb[iu]=ru+1;
+
+ rcrowt[id]=rd-1;
+ rcrowb[id]=rd+1;
+}
+Nt=floor((rcrowt[0]+rcrowb[0])/2);
+Nb=Nv-Nt-Nsyc-2*Nsy*divsy;
+if(verbose > 1)
+ write('#st t b: \t',Nyst,Nt,Nb);
+
+/* vertical lines
+ * (Nh-2*os)/2-Nsx/2 dots available for divisions of Nsx dots.
+ * At least 5 dots margin left and right ==> use -10*os
+ */
+real lsq, Nsx;
+int divsx, Nhc, Nl;
+
+lsq=Nsy*yd;
+Nsx=lsq/xd;
+divsx=floor(((Nh-10*os)/Nsx-1)/2);
+Nhc=round(Nh/2);
+Nl=Nhc-round((1+2*divsx)*Nsx/2);
+if(verbose > 1)
+ write('#Nsx divsx Nl:\t',Nsx,divsx,Nl);
+
+/**** draw gray background ****/
+{
+ path zz;
+ //zz=tvrect(0,0, Nh,Nv, xd,yd,Nv);
+ /* keep white canvas for castellations */
+ zz=tvrect(Nl,Nt, Nh-Nl,Nv-Nb, xd,yd,Nv);
+ fill(zz, p=pdefault+gray(0.5));
+ //dot(zz);
+}
+/**** draw center circle ****/
+real cx, cy, crad;
+pair ccenter;
+path ccirc;
+cx=Nh/2;
+cy=Nv/2-Nshift;
+crad=6*Nsy;
+if(Nv%2 != 0) {
+ crad+=0.5;
+}
+ccenter=tvps(cx,cy, xd,yd,Nv);
+ccirc=circle(ccenter, crad*yd);
+if(colortv<=0) {
+ draw(ccirc, p=pwhite+linewidth(2*yd));
+}
+
+/****** draw 2*divsy+2 horizontal lines **********************************/
+real[] rcang, rcoff;
+pair[] rcright, rcleft;
+int i, iend=2*divsy+1;
+for(i=0; i<=iend; ++i) {
+ real y, phi, x;
+ path zzh;
+ pair zd;
+
+ zzh=tvrect(0,rcrowt[i], Nh,rcrowb[i], xd,yd,Nv);
+ fill(zzh, p=pwhite);
+
+ y=cy-rcrowc[i];
+ //write(roff);
+ if(abs(y)<crad) {
+ phi=asin(y/crad);
+ } else {
+ phi=pi/2;
+ }
+ rcang[i]=phi;
+ x=(crad*cos(phi))*yd/xd;
+ rcoff[i]=x;
+ zd=tvps(cx+x,cy-y, xd,yd,Nv);
+ rcright[i]=zd;
+ //dot(zd);
+ zd=tvps(cx-x,cy-y, xd,yd,Nv);
+ rcleft[i]=zd;
+}
+
+/****** draw 2*divsx+2 vertical lines ***************************/
+int[] coff, coffa, coffb;
+int poffa=0, ccenterwhite=divsx%2;
+for(i=0; i<=divsx; ++i) {
+ real cdist=(1+2*i)*Nsx;
+ int off, offa, offb;
+ path zzv;
+
+ off=round(cdist/2);
+ //write(cdist,off);
+ offa=off+os;
+ offb=off-os;
+
+ coff[i]=off;
+ coffa[i]=offa;
+ coffb[i]=offb;
+
+ //write(Nhc-offa);
+ zzv=tvrect(Nhc+offb,0, Nhc+offa,Nv, xd,yd,Nv);
+ fill(zzv, p=pwhite);
+ zzv=tvrect(Nhc-offa,0, Nhc-offb,Nv, xd,yd,Nv);
+ fill(zzv, p=pwhite);
+
+ /** top castellations, must end with black **/
+ if(i%2 == ccenterwhite) {
+ int j, jnum;
+
+ if(poffa == 0) {
+ poffa=-offb;
+ jnum=1;
+ } else {
+ jnum=2;
+ }
+
+ for(j=0; j<jnum; ++j) {
+ int lc, rc;
+ path zzc;
+
+ if(j==0) {
+ lc=Nhc+poffa;
+ rc=Nhc+offb;
+ } else {
+ lc=Nhc-offb;
+ rc=Nhc-poffa;
+ }
+
+ zzc=tvrect(lc,0, rc,Nt-1, xd,yd,Nv);
+ fill(zzc, p=pblack);
+ zzc=tvrect(lc,Nv-Nb+1, rc,Nv, xd,yd,Nv);
+ fill(zzc, p=pblack);
+ }
+ }
+
+ poffa=offa;
+}
+//write(coff);
+
+/** left and right castellations **/
+/* The bottom right red rectangle tests for a non causal color FIR
+ * filter in the receiver. The last 2..4 dots then typically appear
+ * colorless, green, or cyan.
+ *
+ * This comes from the fact that the chroma subcarrier is of lower
+ * bandwidth than luma and thus continues after the last active sample.
+ * These trailing (y,u,v) samples result from a signal to zero
+ * transition and depend on the transmit and receive filters. Samples
+ * from VHS, system B/G/D/K, system I, or a DVD player output are
+ * different. Nevertheless, a sharpening filter uses this data and so
+ * adds false color to the last dots.
+ */
+int lc, rc;
+iend=2*divsy+1;
+lc=Nhc-coffa[divsx];
+rc=Nhc+coffa[divsx];
+for(i=1; i<=iend; ++i) {
+ pen pcast;
+ if(i == iend && colortv>0) {
+ pcast=pdefault+rgb(0.75,0.0,0);
+ } else {
+ pcast=pblack;
+ }
+ if(i%2 == 1) {
+ int tr, br;
+ path zzc;
+
+ tr=rcrowb[i-1];
+ br=rcrowt[i];
+ zzc=tvrect( 0,tr, lc,br, xd,yd,Nv);
+ fill(zzc, p=pblack);
+ zzc=tvrect(rc,tr, Nh,br, xd,yd,Nv);
+ fill(zzc, p=pcast);
+ }
+}
+
+/****** markers for 4/3 aspect ratio ******/
+if(rimage>4/3)
+ rimarkers(rimage, Nh, Nhc, os, Nvc, Nsy, pwhite, xd, yd, Nv);
+
+/****** line pairing center ******/
+centerline(coff, coffa, coffb, Nhc, divsx, os, rcrowc, Nvc, divsy,
+ ccenter, rcoff, rcright, rcleft, pdefault, xd, yd, Nv);
+
+if(colortv>0) {
+ /* topbw structure */
+ topbw(coff, Nhc, os, rcrowc[divsy-5], rcrowc[divsy-4], rcrowc[divsy-3],
+ ccenter, rcleft[divsy-4], rcleft[divsy-3], rcright[divsy-4],
+ rcright[divsy-3], pdefault, xd, yd, Nv);
+
+ /* 250 kHz */
+ testtone(Ttone, rcrowc[divsy-3], rcrowc[divsy-2],
+ cx, cy, crad, pdefault, xd, yd, Nv);
+
+ /* color bars */
+ colorbars(coff, Nhc, rcrowc[divsy-2], rcrowc[divsy-1], rcrowc[divsy],
+ ccenter, rcleft[divsy-2], rcleft[divsy], rcright[divsy-2],
+ rcright[divsy], pdefault, xd, yd, Nv);
+
+ /* test frequencies */
+ testfreqs(ftones, coff, Nhc, rcrowc[divsy+1], rcrowc[divsy+2],
+ rcrowc[divsy+3], ccenter, rcleft[divsy+1], rcleft[divsy+3],
+ rcright[divsy+1],rcright[divsy+3], pdefault, xd, yd, Nv);
+
+ /* gray bars */
+ graybars(coff, Nhc, rcrowc[divsy+3], rcrowc[divsy+4], ccenter,
+ rcleft[divsy+3], rcleft[divsy+4],
+ rcright[divsy+3], rcright[divsy+4], pdefault, xd,yd,Nv);
+
+ /* PAL ears */
+ if(colortv==1) {
+ palears(coff,coffa,coffb, Nhc, rcrowt, rcrowb, Nvc, divsy, -1,
+ pdefault, xd, yd, Nv);
+ palears(coff,coffa,coffb, Nhc, rcrowt, rcrowb, Nvc, divsy, 1,
+ pdefault, xd, yd, Nv);
+ } else if(colortv==2) {
+ ntscbars(coff,coffa,coffb, Nhc, rcrowt, rcrowb, Nvc, divsy, -1,
+ pdefault, xd, yd, Nv);
+ ntscbars(coff,coffa,coffb, Nhc, rcrowt, rcrowb, Nvc, divsy, 1,
+ pdefault, xd, yd, Nv);
+ ntscbars(coff,coffa,coffb, Nhc, rcrowt, rcrowb, Nvc, divsy, -2,
+ pdefault, xd, yd, Nv);
+ ntscbars(coff,coffa,coffb, Nhc, rcrowt, rcrowb, Nvc, divsy, 2,
+ pdefault, xd, yd, Nv);
+ }
+
+ /* bottom wh - black - wh */
+ bottombw(round((coff[2]+coff[3])/2), Nhc, rcrowc[divsy+4], rcrowc[divsy+5],
+ ccenter, rcleft[divsy+4], rcleft[divsy+5],
+ rcright[divsy+4], rcright[divsy+5], pdefault, xd, yd, Nv);
+
+ /* bottom yellow red circle */
+ bottomcirc(coff[0], Nhc, rcrowc[divsy+5], cx, cy, crad,
+ ccenter, rcleft[divsy+5], rcright[divsy+5], pdefault, xd, yd, Nv);
+}
+
+/********************** set id *********************/
+{ /* dpi */
+ pair rpos=tvps(Nhc,round((rcrowc[divsy-4]+rcrowc[divsy-5])/2), xd,yd,Nv);
+ string iRhor, iRver, ires;
+ real Rh, Rv;
+
+ Rh=Nh/xsize*inch;
+ Rv=Nv/ysize*inch;
+ iRhor=format("%.4gx", Rh);
+ iRver=format("%.4gdpi", Rv);
+ ires=insert(iRver,0, iRhor);
+
+ /* size info */
+ int rowbot=round((rcrowc[divsy+4]+rcrowc[divsy+5])/2);
+ pair tpos=tvps(Nhc,rowbot, xd,yd,Nv);
+ string ihor, iver, itot, iasp, ifm;
+ real asp, fm;
+
+ ihor=format("%ix",Nh);
+ iver=format("%i ",Nv);
+ itot=insert(iver,0, ihor);
+ asp=xsize/ysize;
+ iasp=format("%.3g ",asp);
+ fm=fs/1e6;
+ ifm=format("%.4gMHz",fm);
+ itot=insert(iasp,0, itot);
+ itot=insert(ifm,0, itot);
+
+ /* size of square */
+ int rowNsy=round((rcrowc[divsy+5]+rcrowc[divsy+6])/2);
+ pair Npos=tvps(Nhc+round((coff[4]+coff[5])/2),rowNsy, xd,yd,Nv);
+ string iNsy=format("%i",Nsy);
+
+ pen pbw;
+ if(colortv>0) {
+ pbw=pdefault+gray(1.0);
+ } else {
+ pbw=pdefault+gray(0.0);
+ }
+ label(ires, rpos, p=pbw);
+ label(itot, tpos, p=pbw);
+ label(iNsy, Npos, p=pbw);
+ if(verbose > 1)
+ write('#res:\t', ires, itot, iNsy);
+}
+