[GRASS-dev] [GRASS GIS] #3293: r.texture: very slow when size is increased

[GRASS GIS]

#3293: r.texture: very slow when size is increased
--------------------------+-----------------------------
  Reporter:  mlennert     |      Owner:  grass-dev@…
      Type:  enhancement  |     Status:  new
  Priority:  normal       |  Milestone:  7.4.0
 Component:  Raster       |    Version:  svn-trunk
Resolution:               |   Keywords:  r.texture speed
       CPU:  Unspecified  |   Platform:  Unspecified
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Comment (by mmetz):

 Replying to [ticket:3293 mlennert]:
 > Running
 >
 >
 > {{{
 > r.texture -a ortho_2001_t792_1m size=27 out=text_ortho_27
 > }}}
 >
 > in the NC demo data set took the following time:
 >
 >
 > {{{
 > real  339m54.922s
 > user  339m44.824s
 > sys   0m5.464s
 > }}}
 >
 > This seems excessively long, especially when the relevant literature
 cites common sizes of 20-50 (see #3210 for a discussion).

 Note that e.g. Haralick et al. (1973) did not use a moving window
 approach, instead texture measurements were calculated for selected blocks
 and the output is not a raster map but a single value for each texture
 measurement and each block.
 >
 > It would be great if this could somehow be accelerated.

 Maybe by processing moving windows in parallel, at the cost of allocating
 / freeing memory for each moving window.

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Ticket URL: <https://trac.osgeo.org/grass/ticket/3293#comment:1>
GRASS GIS <https://grass.osgeo.org>