image resize

PImage img1=loadImage("XXX.png"); 

PImage img2 = createImage(img1.width,img1.height); 

img2.copy(img1,0,0,img1.width,img1.height,0,0,img1.width,img1.height); 

img1.resize(img1.width/2,img1.height); 

img1.copy(img2,0,0,img2.width,img2.height,0,0,img1.width,img1.height); 

img1.resize(img1.width/2,0);  // 1/2 x 1/2 ??