try this:
Code:

PImage b;

void setup() {
  size(256,192);  
}
 
void draw(){
 b = loadImage("a.jpg");
 image(b,0,0);
} 
 

You could also loadImage in the setup()

Thanks for the replies. I tried those options and they both work as expected. I was trying avoid placing the loadImage in void draw to avoid re-drawing the image each frame. But my problem is that I am loading images that are being rewritten/abstracted as a representation of binary code (ones and zeros being imported from a binary generator in pd via OSC). The image appears digit by digit, line by line as the binary numbers down the screen. This part of the code works with single images but I need to call up several images in sequence for this project. When the image has been completely drawn on the screen, a new image needs to be loaded and drawn over the previous image line by line. To test it I just set it up with two images that will switch back and forth.

I tried to do the following outside of void draw :

void changePic() {
 if(currentpic==0) {currentpic = 1; img = loadImage("b.jpg");}
 if(currentpic==1) {currentpic = 0; img = loadImage("a.jpg");}
}

Kevin McCoy and I got it to work. We brought the binary generator into processing, removed the data from pd coming via OSC all together and wrote a new "void imageNumber" for each image we need to call. It is easy to run through a sequence. If any one knows why a PImage variable cant be re-designated as we had tried to do in our first try please let me know.

thanks, working code follows (for some reason I cant to figure out how to post code as "code" with my browser so I have to paste it as it appears below):


int posx = 0;
int posy = 0;
int numdivx = 256;
int numdivy = 192;

int imageLink = 0;

int r;
String binseq;
int refPoint = 0;
boolean parsed = true;
char message;

PImage a;
PImage b;

//int currentpic = 0;
 

void setup() {
 //define PImages
a = loadImage("a.jpg");
b = loadImage("b.jpg");
//
 PFont fontA = loadFont("Verdana-6.vlw");
 textFont(fontA, 6);
 size(1024,768);
 frameRate(800);
 background(255);
 noStroke();
 fill(0);

}





// The font must be located in the sketch's
// "data" directory to load successfully
//fonty = loadFont("Verdana-12.vlw");

void draw() {
 
  if (parsed==false) {
    message = binseq.charAt(refPoint);
    refPoint+=1;
    //println(refPoint);
    if(refPoint>7) {refPoint = 0; parsed = true;}
    imageChooser();
   
  }
  if (parsed==true) {
     r = int(random(128, 256));
     binseq = binary(r);
     //println(binseq);
     parsed = false;
  }
}


void imageChooser() {
 if(imageLink==0) {imageOne();}
 if(imageLink==1) {imageTwo();}
}


void imageOne(){

 //fill(255,5);
 //rect(0,0,width,height);
 int msgval = message;
 if(msgval=='1'){
 fill(255);
 rect(width/numdivx*posx,height/numdivy*posy,width/numdivx,height/numdivy);
 fill(a.get(posx,posy),30);
 rect(width/numdivx*posx,height/numdivy*posy,width/numdivx,height/numdivy);
 fill(a.get(posx,posy));
 pushMatrix();
 translate(0,height/numdivy);
 text("1",width/numdivx*posx,height/numdivy*posy);
 popMatrix();
 } else{
   fill(255);
   rect(width/numdivx*posx,height/numdivy*posy,width/numdivx,height/numdivy);
   fill(a.get(posx,posy),30);
 rect(width/numdivx*posx,height/numdivy*posy,width/numdivx,height/numdivy);
   fill(a.get(posx,posy));
   pushMatrix();
   translate(0, height/numdivy);
   text("0",width/numdivx*posx,height/numdivy*posy);
   popMatrix();
 }
 
 posx+=1;
 if(posx==numdivx){
   if(posy==numdivy-1) {
     imageLink = 1;
   }
 }
 if(posx>numdivx) {posx = 0; posy+=1;}
 if(posy>numdivy-1) {posy = 0;}
}

void imageTwo(){
 //fill(255,5);
 //rect(0,0,width,height);
 int msgval = message;
 if(msgval=='1'){
 fill(255);
 rect(width/numdivx*posx,height/numdivy*posy,width/numdivx,height/numdivy);
 fill(a.get(posx,posy),30);
 rect(width/numdivx*posx,height/numdivy*posy,width/numdivx,height/numdivy);
 fill(b.get(posx,posy));
 pushMatrix();
 translate(0,height/numdivy);
 text("1",width/numdivx*posx,height/numdivy*posy);
 popMatrix();
 } else{
   fill(255);
   rect(width/numdivx*posx,height/numdivy*posy,width/numdivx,height/numdivy);
   fill(a.get(posx,posy),30);
 rect(width/numdivx*posx,height/numdivy*posy,width/numdivx,height/numdivy);
   fill(b.get(posx,posy));
   pushMatrix();
   translate(0, height/numdivy);
   text("0",width/numdivx*posx,height/numdivy*posy);
   popMatrix();
 }
 
 posx+=1;
 if(posx==numdivx){
   if(posy==numdivy-1) {
     imageLink = 0;
   }
 }
 if(posx>numdivx) {posx = 0; posy+=1;}
 if(posy>numdivy-1) {posy = 0;}
}