rgb delayed (solved)

afonso_castro

Helou.

whats the way to make a typical RGB delayed video fx.

thks!!

koogs

there's nothing built-in, you'll have to code it yourself

use a circular buffer.

store images as they become available.

copy current red pixels, old green pixels and older blue pixels to screen

(actually, thinking about it, you can store only the green and blue values from the pixels, 1 byte rather than 4. and if you store them in different buffers, the green buffer can be shorter than the blue)

| red (live, not stored)
|xxxxx| green (5 frames stored)
|xxxxxxxxxx| blue (10 frames stored)

(5 and 10 are just examples, adjust depending on delay)

afonso_castro

well, i need study the buffer.

some more ideas?

thks

jeremydouglass

@afonso_castro --

RGB delayed video

You mean this kind of effect, correct? https://vimeo.com/59434848

afonso_castro

Yes....i try it in diferents ways.....

is easy on Pd or max jitter

but.......

afonso_castro

my working about....some ideas?

import processing.video.*;

Capture cam;

PImage[] buffer;

int w = 640;

int h = 460;

int nFrames = 10;

int iWrite = 0, iRead = 1;

void setup(){
  size(640,480);
  cam = new Capture(this, w, h);
  cam.start();
  buffer = new PImage[nFrames];
}

void draw() {
  if(cam.available()) {
    cam.read();
    image(cam,0,0);

    buffer[iWrite] = cam.get();
    if(buffer[iRead] != null){
      tint(255,120);
      image(buffer[iRead], 0, 0);
    }
    iWrite++;
    iRead++;
    if(iRead >= nFrames-1){
      iRead = 0;
    }
    if(iWrite >= nFrames-1){
      iWrite = 0;
    }
  }       
}

kfrajer

Please edit your post and format your code. Select your code and press ctrl+o and have an empty line above and below your code.

Kf

kfrajer

I tried two ways. Below you will find two lines tagged with the key word Effect. Enable only one line at the time to see the results.

In a nutshell, it displays the latest video plus 9,7,5 frames before, each mask in the following sequence: R,G,B

EFFECT1: Final results sees the combination of the three color masks.
EFFECT2: More of a subtle color masking effect

Kf

import processing.video.*;

Capture cam;

PImage[] buffer;

int w = 640;
int h = 460;
int nFrames = 10;
int iWrite = 0, iRead = 1;

void setup() { 
  size(640, 480); 
  println(cam.list());
  cam = new Capture(this);//, width,height); 
  cam.start(); 
  buffer = new PImage[nFrames];
}

void draw() { 
  if (cam.available()) { 
    cam.read(); 
    displayImg(cam, 0xA0ffffff);  //EFECT1: disabled EFFECT2, below

    buffer[iWrite] = cam.get();

    int _iRead=iRead;

    if (buffer[_iRead] != null) {      
      displayImg(buffer[iRead], 0x80ff0000);//Gets red channel and applies an alpha of 0x80 or 128 decimal.
    }

    _iRead=nextPos(_iRead,2);

    if (buffer[_iRead] != null) {      
      displayImg(buffer[_iRead], 0x4000ff00); //Gets green channel
    }

    _iRead=nextPos(_iRead,2);

    if (buffer[_iRead] != null) {      
      displayImg(buffer[_iRead], 0x400000ff); //Gets blue channel
    }

    //displayImg(cam, 0xA0ffffff); //EFECT2: disabled EFFECT1, above



    iWrite++;
    iRead++;


    if (iRead == nFrames-1) {
      iRead = 0;
    }
    if (iWrite == nFrames-1) {
      iWrite = 0;
    }
  }
}

void displayImg(PImage in, int mask) {

  PImage cpy = in.get();
  cpy.loadPixels();
  for (int i=0; i<cpy.width*cpy.height; i++) {
    cpy.pixels[i] &=mask;   
  }
  cpy.updatePixels();
  image(cpy, 0, 0);
}

//Function to find next available proper position, simulating a ring structure
// cp: current position
// jump: Steps to jump from current position
// nFrames: Implicity needed, constrain value of position (aka. size of array)
int nextPos(int cp,int jump) {

  int vr=cp+jump;

  if(vr<nFrames)
  return vr;
  //NEXT nFrames=10 and jump=3
  //cp cp+jump  Returned
  // 7   10        0
  // 8   11        1
  // 9   12        2

  return vr-nFrames;
}

afonso_castro

i try to change the code....but i did not It........maybe Safari :(

I put the code in middle of the (``) but no work

sorry

koogs

`` are more for single lines of code

Edit the post, highlight the whole code, press Ctrl-o. The code will indent and should appear OK on a refresh.

afonso_castro

Well, i was working on sketch and this is the result.

some more ideas ?

tks

   import processing.video.*;

Capture cam;
PImage[] buffer;
Capture img;
int w = 640;
int h = 480;
int nFrames = 10;
int[] camR;
int iWrite = 0, iRead = 1;

void setup(){
  size(640,480);
  cam = new Capture(this, w, h);
  img = new Capture (this, w, h);
  cam.start();
 // for (int i = 0; i < w; i++) {

//for (int j = 0; j < h; j++) {



//int loc = (cam.width – i – 1) + j*cam.width;
// iWrite = int (red(cam.pixels[i + j*cam.width/255]));
//float b = brightness(cam.pixels[loc]);
}
  }
  buffer = new PImage[nFrames];
}

void draw() {
  if(cam.available()) {
    cam.read();
    img.read();
    //background(cam);

for (int i = 0; i < width;i++) 
  {
    for (int j = 0; j <height;j++) 
    {
      int loc = i + j*width;

      int pixelColour = cam.pixels[loc];

      float r = (pixelColour >> 16) & 0xff;
      float g = (pixelColour >> 8) & 0xff;
      float b = pixelColour & 0xff;
      r = (r*1.0);
      g = (g*1.0);
      b = (b*1.0);
       cam.pixels[loc] =  color(0,g,0); 
       img.pixels[loc] = color(r,g,b);        //img=cam;
      img.updatePixels();
      cam.updatePixels();
    }
  }

    buffer[iWrite] = cam.get();

    if(buffer[iRead] != null){
     // tint(255,200);
       image(buffer[iRead],0,0);
       //  tint(255,100);
      background(img);



   blend(buffer[iRead],0,0,w,h,0,0,w,h,LIGHTEST);
    updatePixels();

    }
    iWrite++;
    iRead++;
    if(iRead >= nFrames-1){
      iRead = 0;
    }
    if(iWrite >= nFrames-1){
      iWrite = 0;
    }
  }       
}

koogs

iWrite++;
iRead++;
if(iRead >= nFrames-1){
  iRead = 0;
}
if(iWrite >= nFrames-1){
  iWrite = 0;
}

can be rewritten using the % operator

iWrite = (iWrite++) % nFrames;
iRead = (iRead++) % nFrames;

GoToLoop

No need for double-reassigning the variables w/ the increment operator: L-)

iWrite = (iWrite + 1) % nFrames;
iRead  = (iRead  + 1) % nFrames;

afonso_castro

And finally, i made something like i`d like.

import processing.video.*;
Capture myCap;
Capture G;
Capture B;
int capW = 320;
int capH = 240;

int nDelayFrames = 10; // about 3 seconds
int nDelayFramesB = 21;
int currentFrame = nDelayFrames-1;
int currentFrameB = nDelayFramesB-1;
PImage frames[];
PImage framesB[];

void setup() {
  size (640, 480);
  myCap = new Capture(this, width, height);
  G = new Capture(this, width, height);
   B = new Capture(this, width, height);
  myCap.start();

  frames = new PImage[nDelayFrames];
  for (int i=0; i<nDelayFrames; i++) {
    frames[i] = createImage(width, height, ARGB);
  }
    framesB = new PImage[nDelayFramesB];
  for (int i=0; i<nDelayFramesB; i++) {
    framesB[i] = createImage(width, height, ARGB);
  } 
}

void draw() {
  if (myCap.available()) {
    myCap.read();
    G.read();
    B.read();
    for (int d = 0; d < width;d++) 
  {
    for (int j = 0; j <height;j++) 
    {
      int loc = d + j*width;

      int pixelColour = myCap.pixels[loc];

      float r = (pixelColour >> 16) & 0xff;
      float g = (pixelColour >> 8) & 0xff;
      float b = pixelColour & 0xff;
      r = (r*1.0);
      g = (g*1.0);
      b = (b*1.0);
       myCap.pixels[loc] =   color(r,g,b); 
       G.pixels[loc] = color(0,g*2,0); 
        B.pixels[loc] = color(0,0,b*2);  //img=cam;
      G.updatePixels();
        B.updatePixels();
      myCap.updatePixels();
    }
  }
    frames[currentFrame].loadPixels();
    arrayCopy (G.pixels, frames[currentFrame].pixels);
    frames[currentFrame].updatePixels();
    currentFrame = (currentFrame-1 + (nDelayFrames)) % nDelayFrames;

    framesB[currentFrameB].loadPixels();
    arrayCopy (B.pixels, framesB[currentFrameB].pixels);
    framesB[currentFrameB].updatePixels();
    currentFrameB = (currentFrameB-1 + nDelayFramesB) % nDelayFramesB;
  } 
 // tint(0,255,0,160);
  image (frames[currentFrame], 0, 0, width, height);
  //updatePixels();
   //tint(0,0,255,140);
  image (framesB[currentFrameB], 0, 0, width, height);
   tint(255,100);
  image(myCap,0,0,width, height);

  }

kittrick

Hi all, here is a version that is using blend modes instead of tints, the result is an image that is not as tinted and a little bit cleaner code.

    import processing.video.*;
    Capture rCap;
    Capture gCap;
    Capture bCap;
    
    int nDelayFrames = 10; // about 3 seconds
    int nDelayFramesB = 21;
    int currentFrame = nDelayFrames-1;
    int currentFrameB = nDelayFramesB-1;
    PImage frames[];
    PImage framesB[];
    
    void setup() {
      size (640, 480);
      rCap = new Capture(this, width, height);
      gCap = new Capture(this, width, height);
      bCap = new Capture(this, width, height);
      rCap.start();
    
      frames = new PImage[nDelayFrames];
      for (int i=0; i> 16) & 0xff;
            int g = (pixelColour >> 8) & 0xff;
            int b = pixelColour & 0xff;
            rCap.pixels[loc] = color(r, 0, 0); 
            gCap.pixels[loc] = color(0, g, 0); 
            bCap.pixels[loc] = color(0, 0, b);
            rCap.updatePixels();
            gCap.updatePixels();
            bCap.updatePixels();
          }
        }
        frames[currentFrame].loadPixels();
        arrayCopy (gCap.pixels, frames[currentFrame].pixels);
        frames[currentFrame].updatePixels();
        currentFrame = (currentFrame-1 + (nDelayFrames)) % nDelayFrames;
        framesB[currentFrameB].loadPixels();
        arrayCopy (bCap.pixels, framesB[currentFrameB].pixels);
        framesB[currentFrameB].updatePixels();
        currentFrameB = (currentFrameB-1 + nDelayFramesB) % nDelayFramesB;
      }
    
      blendMode(NORMAL);
      // RED
      image(rCap, 0, 0, width, height);
      blendMode(SCREEN);
      // BLUE
      image (framesB[currentFrameB], 0, 0, width, height);
      // GREEN
      image (frames[currentFrame], 0, 0, width, height);
    }

kfrajer

Hi @kittrick

Thanks for sharing your answer. However your code doesn't work. You are missing few lines as I have a mismatch curly bracket and there is no draw function in your code.

Kf