Image Dithering: Eleven Algorithms and Source Code
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Image Dithering: Eleven Algorithms and Source Code
1–10 of 65 posts
Re: Image Dithering: Eleven Algorithms and Source Code
#2This thesis on image dithering and noise shaping is one of the best works I've read on the subject: http://uwspace.uwaterloo.ca/bitstream/10012/3867/1/thesis.pd...
Re: Image Dithering: Eleven Algorithms and Source Code
#3I sense a disturbance in the force. It's as if 1,000 BitCam clones were just born.
Re: Image Dithering: Eleven Algorithms and Source Code
#4Back when I was at university, we had a computer graphics course. Each week we got new assignment that we needed to program, write to a floppy disk (it was before Internet became widely available) and give it to the prof next week.
Dithering was one of the assignments. We were required to implement black-white quantization and then Atkinson and Floyd-Steinberg. We were given the freedom to choose our own images.
During development at the dorm my favourite picture to debug on was pretty racy (think along the lines of full version of "Lena"). I totally did not intend to put it to the floppy disk...
Not only I got the 10 - the highest number of points for this assignment, I got +2 on top of that with the comment from prof: "for the choice of test images in the best tradition of the field".
Re: Image Dithering: Eleven Algorithms and Source Code
#5Back when I was at university, we had a computer graphics course. Each week we got new assignment that we needed to program, write to a floppy disk (it was before Internet became widely available) and give it to the prof next week. Dithering was one of the assignments. We were required to implement black-white quantization and then Atkinson and Floyd-Steinberg. We were given the freedom to choose our own images. Duri…
Gross.
Re: Image Dithering: Eleven Algorithms and Source Code
#6I don't know if it's some kind of nostalgia factor (since a lot of old 16-color EGA software used it, I think), but I find ordered dithering output strangely appealing. I have also used it sometimes where size mattered more than style on the assumption that GIF/PNG compression rates would be better on ordered dithers. ImageMagick can do a lot of dithering styles and it's fun to play with.
Re: Image Dithering: Eleven Algorithms and Source Code
#7This thesis on image dithering and noise shaping is one of the best works I've read on the subject: http://uwspace.uwaterloo.ca/bitstream/10012/3867/1/thesis.pd...
Professor Vanderkooy is a great source for dithering, and has some wonderful work on it too (ps. fellow uw student)
Re: Image Dithering: Eleven Algorithms and Source Code
#8Back when I was at university, we had a computer graphics course. Each week we got new assignment that we needed to program, write to a floppy disk (it was before Internet became widely available) and give it to the prof next week. Dithering was one of the assignments. We were required to implement black-white quantization and then Atkinson and Floyd-Steinberg. We were given the freedom to choose our own images. Duri…
Gross.
I understand your sentiment. I did not mean to glorify objectification of women with this story. Just something mildly funny that happened almost two decades ago, in a country without a strong tradition of feminism, to a 17-year old me who did not know any better then.
Re: Image Dithering: Eleven Algorithms and Source Code
#9This was a great read. Very approachable.
Re: Image Dithering: Eleven Algorithms and Source Code
#10> It also has uses when reducing 48 or 64bpp RAW-format digital photos to 24bpp RGB for editing.
The author touches upon it here, but I think it's worth generalizing further: If you have high or maybe infinite precision in your color values, dithering will look much nicer than simply rounding to the nearest value. A concrete example is a color gradient. If done naively with rounding, color bands will be clearly visible. With dithering, they will be almost impossible to see.
See for example: http://johanneshoff.com/dithering/