Notebook-Scanner

Background

On my website I'd like to incorporate more diagrams and drawings to make my article explanations clearer. However, I find drawing things out with a mouse to be such a pain that I won't do it, even though it looks much better than a drawing on paper. As such I developed this program as a way to digitize my notebook paper drawings; they look much better digitized and it provides me the ability to easily rearrange things if need be.

While my main use-case is for digitizing diagrams, it also works quite well as a normal scanner with results comparable to Google's scanner (i'm not making the bold claim that it's as good as Google's, but for scanning notebooks it's comparable).

Test Image Results

Original Image	Scanned Output

Original Image	Scanned Output

My Scanner	Google Scanner

Using the Program

Color Limitations

Only the colors of pure black, red, blue, and green are supported by the program. This is simply because I don't have a need for more than this, however you could pretty easily modify the k-means++ classifier to support more colors.

Image Taking Recommendations

If you want only the writing and not the notebook lines scanned, you may have some trouble depending on your notebook paper; my primary notebook happens to have relatively light horizontal lines which makes the process easier. If you have thick lines I'd recomend writing in pen, as well as taking your picture close enough so no auto-cropping is needed. You will also probably need to use manual mode (flag explained below).

Example of Running the Program

python3 scan.py test_images/test_color.jpg --colors r,g,b,bl --output test_color_output

Program Flags

Flag	Description	Default
--output	string Output image filename (saves as .png).	ink
--manual	bool Opens an interactive window with a slider to manually select the brightness threshold. • s: Confirm selection • q: Quits program.	False
--transparent	bool Saves the output .png image with a transparent background instead of a white one.	False
--crop_only	bool Only performs the perspective warp/cropping to the notebook paper; skips all further image processing.	False
--colors	tuple Specify which pen colors are present. Arguments: r, g, b, bl (Red, Green, Blue, Black).	bl
--ink	string Determines how black writing is processed: • og: Samples original ink colors • gray: Converts ink to grayscale • bw: Forces pure black • std: Standard processed ink	std
--help, -h	Show the help message and exit.	—