Firstly, I use the camera to capture the users’ video. And use the code to capture people’s outline and fill it with black shadow.

Then, I write a randomly falling down letters generator. It produces randomly letters in the random position in the top. The letters will fall down if it doesn’t meet the black shadow.

Here’s code link:https://github.com/doukooo/textrain

import processing.video.*;

Capture video;
PImage show;
float threshold=50;
PFont f;

void setup(){
f=createFont("Arial",16,true);
size(320,240);
video=new Capture(this,width,height,50);
video.start();
}
int i=0,j=0;
int count=1;
FallLetter[] fallLet=new FallLetter[1];
FallLetter[] newFallLet;
void draw(){
if(video.available()){
video.read();
}
loadPixels();
video.loadPixels();
for(int x=0;x<video.width;x++)
{
for(int y=0;y<video.height;y++)
{
int loc=x+y*video.width;
color cur=video.pixels[loc];
float num=brightness(cur);
if(num>threshold)
{
pixels[loc]=color(255);
}
else
{
pixels[loc]=color(0);
}
}
}
updatePixels();
delay(50);
textFont(f,14);
fill(150,123,0);
int randI=int(random(640));
int randCh=int(random(65,90));
newFallLet=new FallLetter[count];
//deal with every letter
for(int n=0;n<count;n++)
{
if(n==count-1)
newFallLet[n]=new FallLetter(randI,randCh);
else
newFallLet[n]=fallLet[n];
char show=newFallLet[n].GetCh();
int xLoc=newFallLet[n].GetxLoc();
int yLoc=newFallLet[n].GetyLoc();
if(yLoc!=240)
{
text(show,xLoc,yLoc);
//if(red(pixels[xLoc+yLoc*width])==0&&green(pixels[xLoc+yLoc*width])==0&&blue(pixels[xLoc+yLoc*width])==0)
if(yLoc>0)
{
if(brightness(pixels[xLoc+yLoc*width])<100)
newFallLet[n].UpdateY(-1);
else
{
newFallLet[n].UpdateY(1);
}
}
}
}
fallLet=new FallLetter[count];
fallLet=newFallLet;
count++;

}
class FallLetter{

int xLocation,yLocation=10,ch;
char chShow;
FallLetter(int xLoc,int word)
{
xLocation=xLoc;
chShow=char(word);
}
//falling y position update
void UpdateY(int yLoc)
{
yLocation+=yLoc;
}
//get the position and char of the instance
int GetxLoc()
{
return xLocation;
}
int GetyLoc()
{
return yLocation;
}
char GetCh()
{
return chShow;
}
}