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[evoheyax]

So after researching how to solve captcha, thanks to the programmers who don't want to disclose their better methods and my low amount of time to find a better method, the only thing that came up was finding the darkest pixel, which does actually work pretty well. So heres some javascript code that does just that:

function rgbToHsl(r, g, b) {
    r /= 255, g /= 255, b /= 255;
    var max = Math.max(r, g, b),
        min = Math.min(r, g, b);
    var h, s, l = (max + min) / 2;

    if (max == min) {
        h = s = 0; // achromatic
    } else {
        var d = max - min;
        s = l > 0.5 ? d / (2 - max - min) : d / (max + min);
        switch (max) {
            case r:
                h = (g - b) / d + (g < b ? 6 : 0);
                break;
            case g:
                h = (b - r) / d + 2;
                break;
            case b:
                h = (r - g) / d + 4;
                break;
        }
        h /= 6;
    }

    return ({
        h: h,
        s: s,
        l: l,
    });
}

function solve_captcha(url, callback) {
	var captcha = new Image();
	captcha.src = url;
	//alert(url);
	
	captcha.onload = function(){
		var canvas = document.createElement('canvas');
		canvas.width  = 200;
		canvas.height = 200;
		
		var context = canvas.getContext("2d");
		context.drawImage(captcha, 0, 0);
	
		var imgData = context.getImageData(0, 0, 200, 200);

		var pixel = 0;
		var darkest_pixel_lightness = 100;
		var darkest_pixel_location = 0;
		for (var i = 0; i < imgData.data.length; i += 4) {
			red = imgData.data[i + 0];
			green = imgData.data[i + 1];
			blue = imgData.data[i + 2];
			alpha = imgData.data[i + 3];

							// skip transparent/semiTransparent pixels
			if (alpha < 230) {
				continue;
			}
			
			var hsl = rgbToHsl(red, green, blue);
			var lightness = hsl.l;

			if (lightness < darkest_pixel_lightness) {
				darkest_pixel_lightness = lightness;
				darkest_pixel_location = pixel;
			}

			pixel++;
		}
		
		var y = Math.floor(darkest_pixel_location/200);
		var x = darkest_pixel_location-(y*200);
		
		callback(x,y);
	}
}

to use this call a function like this:

captcha_url = 'http://www.neopets.com/captcha_show.phtml?_x_pwned=6f3b55f8983a417085e91ee632b8219b'; // feed live chaptcha link in here
					
solve_captcha(captcha_url, function(x, y) {
    alert('x: '+x+' & y: '+y); // alerts x and y coordinate of where it will click
}

To break it down, you can get the url from the buy page of the captcha, and when inputted into this function along with a callback function, it will do the following:

 

1. Create a new image

2. Set the src of the image to the url of the captcha

3. When the image has loaded, create a new canvas

4. Set height and width of canvas

5. get canvas context.

6. Draw image to canvas context from the image we created in step 1 and 2

6. Get image data from the context (pixel by pixel RGB colors + alpha)

7. Loop through each pixel, converting each pixel to hsl, which gives us the light/dark percentage we need.

8. If we find a pixel darker then any other pixel so far, we save that pixel in the darkest_pixel_variable. If it finds an even darker pixel, that old value will be overridden.

9. Based on the darkest pixel, calculate the x and y coordinate of that pixel

10. Return the x and y to your callback function

 

And your done. I hope this can be helpful to someone trying to learn how to solve captchas