// exercice 1
// conversion en niveaux de gris
// version naive et version CIE

PImage ima = loadImage("ADD.png");
color c,nc;

colorMode(RGB,255,255,255);
size(ima.width,ima.height); 
image(ima,0,0);

for (int x=0;x<width-1;x++){
 for (int y=0;y<height-1;y++){
   c = get(x,y);
   //float gris = (red(c)+green(c)+blue(c))/3;
   float gCIE = 0.299*red(c)+0.587*green(c)+0.114*blue(c);
   //nc = color(gris,gris,gris);
   nc = color(gCIE,gCIE,gCIE);
   set(x,y,nc);
 }
}

//save("resuNAIF.png");
save("resuCIE.png");

/** EXERCICE 2
 Algorithme de Floyd et Sternberg
  P. Cubaud novembre 2007
**/
 
PImage ima;
float cr,gmini,gmaxi,seuil,erreur;
int x,y;
color nc;

ima = loadImage("lennaG.gif");
colorMode(RGB,255,255,255);
size(ima.width,ima.height); 
image(ima,0,0);

gmini = 255;
gmaxi = 0;
for (x=0;x<width;x++){
 for (y=0;y<height;y++){
    cr = red(get(x,y));
    if (gmini > cr){gmini = cr;}
    if (gmaxi < cr){gmaxi = cr;}
   }
  }
print(gmini);print(" ");print(gmaxi);println();
seuil = (gmini + gmaxi)/2;
for (x=0;x<width-1;x++){
 for (y=0;y<height-1;y++){
   cr = red(get(x,y));
   if (cr > seuil) { erreur =  - gmaxi + cr; set(x,y,color(255,255,255)) ;}
   else { erreur = cr - gmini; set(x,y,color(0,0,0)) ; }
   cr = red(get(x+1,y)); nc = color(cr+5*erreur/8,cr+5*erreur/8,cr+5*erreur/8);set(x+1,y,nc);
   cr = red(get(x,y+1)); nc = color(cr+1*erreur/8,cr+1*erreur/8,cr+1*erreur/8);set(x,y+1,nc);
   cr = red(get(x+1,y+1)); nc = color(cr+erreur/4, cr+erreur/4, cr+erreur/4);set(x+1,y+1,nc);
 }
}

/** EXERCICE 3
Morphing entre deux images de meme taille
 
 P. Cubaud novembre 2007
**/
 
PImage imaD, imaF, imaN;
int NIM = 80;
int x,y,k;
float cr,cg,cb;

void setup() {
  imaD = loadImage("depart.gif");
  imaF = loadImage("finale.gif");
  imaN = imaD.get();
  colorMode(RGB,255,255,255);
  size(imaD.width,imaD.height); 
  k = 0;
  //frameRate(1);
}

void draw() {
  for (x=0;x<imaD.width;x++){
   for (y=0;y<imaD.height;y++){
    cr = (k*red(imaF.get(x,y))+(NIM-1-k)*red(imaD.get(x,y)))/NIM;
    cg = (k*green(imaF.get(x,y))+(NIM-1-k)*green(imaD.get(x,y)))/NIM;
    cb = (k*blue(imaF.get(x,y))+(NIM-1-k)*blue(imaD.get(x,y)))/NIM;
    imaN.set(x,y,color(cr,cg,cb));
   }
  }
  image(imaN,0,0);
  k++;
  if (k == NIM) {k = 0; imaN = imaD.get();}
  println(k+" "+cr);
}