GraphicsPhotoshop

Miniature Photoshop which practices multiple fundamental image processing techniques.
Options include:

1. Color to Grayscale
   
2. 24 to 8 bit Color
   
3. Uniform Quantization (4 shades of blue, 8 shades of red, and 8 shades of green)
   
4. Populosity: find the 256 most popular colors, then map the original colors onto their closest chosen color
   
5. Dithering options:
   (1) Dithering
   (2) Naive Threshold Dithering: Dithering with a threshold of 0.5
   (3) Brightness Preserving Threshold Dithering: Using threshold dithering with a threshold chosen to keep the average brightness constant.
   (4) Random Dithering: Adding random values chosen uniformly from the range [-0.2,0.2], assuming that the input image intensity runs from 0 to 1 (scale appropriately)
   (5) Clustered Dithering: cluster dithering with the matrix shown below. The image pixels is compared to a threshold that depends on the dither matrix below. The pixel is drawn white if: I[x][y] >= mask[x%4][y%4]. The matrix is: [0.7059 0.3529 0.5882 0.2353 0.0588 0.9412 0.8235 0.4118 0.4706 0.7647 0.8824 0.1176 0.1765 0.5294 0.2941 0.6471]
   (6) Floyd-Steinberg Dithering: Dither using Floyd-Steinberg dithering (Distribution of error to four neighbors and zig-zag ordering).
   (7) Color Floyd-Steinberg Dithering: Quantize the original image(with color) and use Floyd-Steinberg dithering
   
6. Filtering options:
   (1) Box Filter (5x5)
   (2) Bartlett Filter (5x5)
   (3) Gaussian Filter (5x5)
   (4) Arbitrary-Size Gaussian Filter (nxn)
   
7. Image Resizing options:
   (1) Half size
   (2) Double size
   (3) Arbitrary Uniform Scale scale
   (4) Arbitrary Rotation
   
8. NPR Paint Method: Simplified version of 1998 SIGGRAPH Paper "Painterly Rendering with Curved Brush Strokes of Multiple Sizes"(https://mrl.nyu.edu/publications/painterly98/hertzmann-siggraph98.pdf) Gives image an oil painting like effect.