在單色 LCD 上面利用 PWM 產生灰階的效果
source link: https://blog.gslin.org/archives/2023/01/18/11029/%e5%9c%a8%e5%96%ae%e8%89%b2-lcd-%e4%b8%8a%e9%9d%a2%e5%88%a9%e7%94%a8-pwm-%e7%94%a2%e7%94%9f%e7%81%b0%e9%9a%8e%e7%9a%84%e6%95%88%e6%9e%9c/
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在單色 LCD 上面利用 PWM 產生灰階的效果
Hacker News 上看到「Grayscale on 1-bit LCDs (2022) (zephray.me)」這篇，原文在「Grayscale on 1-bit LCDs」這篇，講在單色的 LCD (黑白的 LCD) 上利用 PWM 的方式來模擬出灰階的效果。
文章蠻有趣的，可以看到他一直在 tune，想辦法做出更多階的灰階效果：
不過其實更有趣的事情是在 Hacker News 的留言裡面，有人起手式就放大招：
My father Bryce Bayer studied this question fifty years ago at Eastman Kodak; his approach is known as ordered dithering:
https://en.wikipedia.org/wiki/Ordered_dithering
One is effectively posterizing a grayscale image, and his primary goal was to reduce artifacts drawing unwanted attention to the borders between poster levels.
With improvements in hardware other approaches to dithering took over. The last time I saw my father's pattern was on a DEC box logo. He moved to the color group at Kodak, and designed the "Bayer filter" used in digital cameras.
不只是提到大名鼎鼎的 Bryce Bayer，開頭直接就 "My father Bryce Bayer ..."。
搜了一下 syzygies 這個用戶名稱，看起來像是 Bryce Bayer 的兒子 Dave Bayer (維基百科也有條目：Dave Bayer)。
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