Linux command
ppmdither 命令
文本
涉及管道、覆盖或删除，执行前请先确认路径和参数。
常用示例
Dither image
ppmdither [input.ppm] > [output.ppm]
Specify colors per channel
ppmdither -red [4] -green [4] -blue [4] [input.ppm] > [output.ppm]
Floyd-Steinberg dithering
ppmdither -fs [input.ppm] > [output.ppm]
说明
ppmdither reduces the number of colors in a PPM image using dithering, which simulates unavailable colors by arranging available colors in patterns that appear blended at a distance. The number of levels per color channel can be specified independently for red, green, and blue. The default uses ordered dithering, while the -fs option selects Floyd-Steinberg error diffusion dithering which generally produces higher quality results with less visible patterning. Unlike quantization (ppmquant), dithering does not choose optimal colors but distributes error across neighboring pixels. Part of the Netpbm toolkit.
参数
- -red _N_
- Red channel levels.
- -green _N_
- Green channel levels.
- -blue _N_
- Blue channel levels.
- -fs
- Floyd-Steinberg dithering.
FAQ
What is the ppmdither command used for?
ppmdither reduces the number of colors in a PPM image using dithering, which simulates unavailable colors by arranging available colors in patterns that appear blended at a distance. The number of levels per color channel can be specified independently for red, green, and blue. The default uses ordered dithering, while the -fs option selects Floyd-Steinberg error diffusion dithering which generally produces higher quality results with less visible patterning. Unlike quantization (ppmquant), dithering does not choose optimal colors but distributes error across neighboring pixels. Part of the Netpbm toolkit.
How do I run a basic ppmdither example?
Run `ppmdither [input.ppm] > [output.ppm]` in a terminal, then adjust file names, paths, flags, or remote targets for your system.
What does -red _N_ do in ppmdither?
Red channel levels.