Sha256: 0903b54a6e82d890ef9f96259bcbce6092c10e07c572cc9942a10e8e72030c09
Contents?: true
Size: 1.41 KB
Versions: 5
Compression:
Stored size: 1.41 KB
Contents
#
# Edge Detection.
#
# A high-pass filter sharpens an image. This program analyzes every
# pixel in an image in relation to the neighboring pixels to sharpen
# the image.
#
KERNEL = [ [ -1, -1, -1 ], [ -1, 9, -1 ], [ -1, -1, -1 ] ]
attr_reader :img
def setup
size(640, 360)
@img = load_image('moon.jpg') # Load the original image
noLoop
end
def draw
image(img, 0, 0) # Displays the image from point (0,0)
img.load_pixels
# Create an opaque image of the same size as the original
edge_img = create_image(img.width, img.height, RGB)
# Loop through every pixel in the image
(1 ... img.height - 1).each do |y|
(1 ... img.width - 1).each do |x|
sum = 0 # Kernel sum for this pixel
(-1 .. 1).each do |ky|
(-1 .. 1).each do |kx|
# Calculate the adjacent pixel for this kernel point
pos = (y + ky)*img.width + (x + kx)
# Image is grayscale, red/green/blue are identical
val = red(img.pixels[pos])
# Multiply adjacent pixels based on the kernel values
sum += KERNEL[ky+1][kx+1] * val
end
end
# For this pixel in the new image, set the gray value
# based on the sum from the kernel
edge_img.pixels[y*img.width + x] = color(sum, sum, sum)
end
end
# State that there are changes to edge_img.pixels[]
edge_img.update_pixels
image(edge_img, width/2, 0) # Draw the new image
end
Version data entries
5 entries across 5 versions & 1 rubygems