pygmt.grdmix

pygmt.grdmix(grid=None, outgrid=None, *, construct=None, deconstruct=None, normalize=None, verbose=None, coltypes=None, **kwargs)

Blending and transforming grids and images.

This function will perform various operations involving images and grids. We either use an alpha grid, image, or constant to add a new alpha (transparency) layer to the image given as raster1, or we will blend the two raster1 and raster2 (grids or images) using the weights for raster1 and the complementary 1 - weights for raster2 and save to outgrid. Alternatively, we will deconstruct an image into its component (red, green, blue or gray) grid layers or we construct an image from its normalized component grids. All operations support adjusting the final color image via an intensity grid, converting a color image to monochrome, or strip off the alpha layer. All raster?, alpha, intensity and weights files must have the same dimensions. The optional alpha, intensity and weights files may be replaced by constant values instead.

Full option list at https://docs.generic-mapping-tools.org/latest/grdmix.html

Aliases:

• C = construct

• D = deconstruct

• G = outgrid

• N = normalize

• V = verbose

• f = coltypes

Parameters

• grid (str or xarray.DataArray or list) – raster?. The file name of the input grid(s) or the grid(s) loaded as a single DataArray. If only one is given and construct is not set then raster1 must be an image. If two are given then raster1 and raster2 must both be either images or grids. If three are given then they must all be grids and construct must be set.

• outgrid (str or None) – The name for the output raster. For images, use one of these extensions: tif (GeoTIFF), gif, png, jpg, bmp, or ppm. For grids, see Grid File Formats.

• construct (bool) – Construct an output image from one or three normalized input grids; these grids must all have values in the 0-1 range only (see normalize="i" if they don’t).

• deconstruct (bool) – Deconstruct a single image into one or three output grids. An extra grid will be written if the image contains an alpha (transparency layer). All grids written will reflect the original image values in the 0-255 range exclusively; however, you can use normalize="o" to normalize the values to the 0-1 range. The output names uses the name template given by outgrid which must contain the C-format string “%c”. This code is replaced by the codes R, G, B and A for color images and g, A for gray-scale images.

• normalize (str) – [i|o][divisor]. Normalize all input grids from 0-255 to 0-1 and all output grids from 0-1 to 0-255. To only turn on normalization for input or output, use normalize="i" or normalize="o" instead. To divide by another value than 255, append an optional divisor.

• region (str or list) – Required if this is the first plot command. xmin/xmax/ymin/ymax[+r][+uunit]. Specify the region of interest.

• verbose (bool or str) –

  Select verbosity level [Default is w], which modulates the messages written to stderr. Choose among 7 levels of verbosity:

  • q - Quiet, not even fatal error messages are produced

  • e - Error messages only

  • w - Warnings [Default]

  • t - Timings (report runtimes for time-intensive algorithms);

  • i - Informational messages (same as verbose=True)

  • c - Compatibility warnings

  • d - Debugging messages

• coltypes (str) – [i|o]colinfo. Specify data types of input and/or output columns (time or geographical data). Full documentation is at https://docs.generic-mapping-tools.org/latest/gmt.html#f-full.