Bryan Chung

The next test is to access each pixel in a bitmap and implement a very simple inverse filter. The image has three channels, red, green and blue and each has a resolution of 8 bits.

Test 1
Flash 8

import flash.display.BitmapData;
var bm:BitmapData = new BitmapData(Stage.width,
   Stage.height, false, 0xFF000000);
var mc1:MovieClip = this.createEmptyMovieClip("mc1",
   this.getNextHighestDepth());
var mc2:MovieClip = this.createEmptyMovieClip("mc2",
   this.getNextHighestDepth());
var ld:MovieClipLoader = new MovieClipLoader();

ld.addListener(this);
ld.loadClip("bear02.jpg", mc1);

function onLoadInit() {
	bm.draw(mc1);
	mc1.removeMovieClip();
	mc2.attachBitmap(bm, 1);
	playColour();
}

function onLoadError() {
	mc1.removeMovieClip();
	trace("load error");
}

function playColour() {
	for (var row:Number = 0; row<bm .height; row++) {
		for (var col:Number = 0; col<bm.width; col++) {
			var c:Number = bm.getPixel32(col, row);
			var r:Number = (c >> 16)& 0xFF;
			var g:Number = (c >> 8)& 0xFF;
			var b:Number = c & 0xFF;
			r = 255-r;
			g = 255-g;
			b = 255-b;
			c = (0xFF << 24)+(r << 16)+(g << 8)+b;
			bm.setPixel32(col, row, c);
		}
	}
}

Test 2
Processing

PImage img;

void setup() {
  size(200, 200);
  background(0);
  img = loadImage("bear02.jpg");
  noLoop();
}

void draw() {
  playColour();
  image(img,0,0);
}

void playColour() {
  for (int row=0; row<height ; row++) {
    for (int col=0; col<width; col++) {
      int n = row*width+col;
      color c = img.pixels[n];
      img.pixels[n] = color(255-red(c),255-green(c),255-blue(c));
    }
  }
  img.updatePixels();
}

Test 3
OpenCV

#include <cv.h>
#include <highgui.h>

int main(int argc, char** argv) {
   IplImage* bm = 0;
   int width, height, step, channel;
	bm = cvLoadImage("bear02.jpg");
	if (!bm) {
		exit(0);
	}
	width = bm->width;
	height = bm->height;
	step = bm->widthStep;
	channel = bm->nChannels;
	cvNamedWindow("win1", CV_WINDOW_AUTOSIZE);
	for (int row=0; row<height ; row++) {
		for (int col=0; col<width; col++) {
			uchar* tmp = &((uchar*)
                          (bm->imageData + row*step))[col*channel];
			tmp[0] = 255 - tmp[0]; // blue
			tmp[1] = 255 - tmp[1]; // green
			tmp[2] = 255 - tmp[2]; // red
		}
	}
	cvShowImage("win1", bm);
	cvWaitKey(0);
	cvReleaseImage(&bm);
	return 0;
}