Color operations¶
Modules to perform color operations on an existing image.
colormap¶
Apply a colormap onto a grayscale image.
This is expected to be passed after creating a spectral index, which transforms the image bands into an index ranging from -1 to 1. Applying a colormap enables better visualization of this range of data.
image Transformation¶
Transforms the internal image object from 1 dimension (grayscale) to 3 dimensions (RGB).
Props¶
imageColormap¶
- Image object, required
Note: make sure you pass format: GL.RGB along with the colormap image;
otherwise the colormap will map the source grayscale image to a different
grayscale image.
The imageColormap image is expected to start as a two-dimensional image that
gradually changes color horizontally through the image. The left side of the
image is expected to correspond to -1, and the right is expected to correspond
to 1.
A collection of colormaps is hosted in the deck.gl-raster repository, but any
image can be used as the colormap. The color value will be chosen horizontally.
For example, for a value of 0, the middle pixel value, horizontally, of the
image will be chosen.
Many colormaps are in assets/colormaps in PNG format, derived from Matplotlib
and rio-tiler. To visualize them, see colormap
documentation.
To use them, you can use the jsdelivr CDN, e.g.:
https://cdn.jsdelivr.net/gh/kylebarron/deck.gl-raster/assets/colormaps/{colormap_name}.png