像素Pixel

交付 · Delivery

像素是空间采样的点——把画面切成网格之后,每一个格子就是一个像素。

  • 格子外没有信息:网格的密度就是空间分辨率;格子没采到的细节永久丢失(见 采样、空间分辨率与时间分辨率)。
  • 像素是数值不是小方块:每个像素是一组数值(R, G, B),调色改的就是这些数值的映射(见 映射(调色))。
  • 放大不发明的部分:把 480p 放大到 4K,网格不会变密——插值只能猜,不能还原没采到的细节。

A pixel is a point of spatial sampling — cut the picture into a grid and each cell is one pixel.

  • Nothing outside the grid: grid density is spatial resolution; detail the grid never sampled is gone for good (see Sampling, Spatial vs Temporal Resolution).
  • A pixel is numbers, not a tiny square: each pixel is a set of values (R, G, B); grading re-maps exactly those numbers (see Mapping).
  • Upscaling invents nothing: blowing 480p up to 4K does not densify the grid — interpolation only guesses; it cannot restore what was never sampled.