kword: an image > ascii converter

I have been tooling around with typewriter “ASCII art” style image reproduction for some time, well, since I acquired my typewriter.

I found several problems with existing image to ASCII generators for my application (reproducing digital images on a typewriter):

• Character set too small (lack of color depth)
• Character set too large (slows typing and adds false textures if asymmetrical characters are used, adds error)
• No custom font (assumes all fonts have same character gradient)
• Character set not weighed at all (character brightnesses should be measured and colors indexed for correct gamma)
• No image adjustments in-converter (monochrome balance, contrast, crop)
• No realtime preview of settings (such as line spacing, font, and line length)
• No dithering option (losing color depth, especially in highlights)

Is a picture worth a 1000 word ASCII image? #

I decided to write an ASCII image generator of my own. It runs in the browser using <canvas> and I call it kword.

Bottom left vs. center: kword optimization at work!

Features: #

• Custom character set
• Floyd-Steinberg dithering
• Measures and indexes character brightness per-font
• Realtime ASCII preview of all settings
• Font, size, print, dither, r, g, b, monochrome, line length, line height

To-do: #

• Curves
• Use font from image
• HDR (layered output)
• Subpixel rendering (each character split into regions for weighing, image upsampled *regions)
• Crop image
• Sliders for line length and line height

Try it #

kword - live demo

kword - source code

More screenshots / generated images #

1-bit Floyd-Steinberg dithering

Works on Presidents