Linux command
pamshadedrelief 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
Create shaded relief
pamshadedrelief [heightmap.pam] > [relief.pam]
Apply gamma correction
pamshadedrelief -gamma [2.0] [heightmap.pam] > [relief.pam]
Pipe to pamtopnm
pamshadedrelief [heightmap.pam] | pamtopnm > [relief.ppm]
Render and encode
pamshadedrelief [heightmap.pam] | pnmtopng > [relief.png]
说明
pamshadedrelief reads a Netpbm PAM file containing a grayscale height map and produces a PAM image rendered as a shaded relief, simulating illumination of a 3D terrain by a virtual light source. Each output pixel encodes the brightness derived from the local slope of the height field, giving a hill-shading effect similar to topographic maps. The input must be a one-channel (grayscale) PAM image; sample values are interpreted as elevations. The illumination angle is fixed by the program. Output samples are gamma-corrected with -gamma so the contrast of the relief can be tuned without re-rendering the source data.
参数
- -gamma _VALUE_
- Apply gamma correction to the output. Values greater than 1 increase contrast in dark areas; values less than 1 reduce it. Default is 1.0.
FAQ
What is the pamshadedrelief command used for?
pamshadedrelief reads a Netpbm PAM file containing a grayscale height map and produces a PAM image rendered as a shaded relief, simulating illumination of a 3D terrain by a virtual light source. Each output pixel encodes the brightness derived from the local slope of the height field, giving a hill-shading effect similar to topographic maps. The input must be a one-channel (grayscale) PAM image; sample values are interpreted as elevations. The illumination angle is fixed by the program. Output samples are gamma-corrected with -gamma so the contrast of the relief can be tuned without re-rendering the source data.
How do I run a basic pamshadedrelief example?
Run `pamshadedrelief [heightmap.pam] > [relief.pam]` in a terminal, then adjust file names, paths, flags, or remote targets for your system.
What does -gamma _VALUE_ do in pamshadedrelief?
Apply gamma correction to the output. Values greater than 1 increase contrast in dark areas; values less than 1 reduce it. Default is 1.0.