Doc: add gdalenhance.rst (fix #8137)

doc/requirements.txt

@@ -1,6 +1,6 @@
 # This file may be used to create an environment using:
 # $ pip install --upgrade -r <this file>
-sphinx
+sphinx < 7.0.0
 breathe
 sphinx_bootstrap_theme
 sphinxcontrib-bibtex
@@ -9,3 +9,4 @@ recommonmark
 sphinx-markdown-tables
 sphinxcontrib-spelling
 sphinxcontrib-jquery
+

doc/source/conf.py

@@ -57,6 +57,7 @@
 #
 html_theme_path = ["."]
 html_theme = "gdal_rtd"
+# html_theme = "classic"
 
 html_context = {
  "display_github": True,

doc/source/programs/gdalenhance.rst

@@ -0,0 +1,76 @@
+.. _gdalenhance:
+
+================================================================================
+gdalenhance
+================================================================================
+
+.. only:: html
+
+ Enhance raster images with LUT-based contrast enhancement.
+
+.. Index:: gdalenhance
+
+Synopsis
+--------
+
+.. code-block::
+
+ gdalenhance [--help-general]
+ [-of format] [-co "NAME=VALUE"]*
+ [-ot {Byte/Int16/UInt16/UInt32/Int32/Float32/Float64/
+ CInt16/CInt32/CFloat32/CFloat64}]
+ [-equalize]
+ [-config filename]
+ <src_raster> <dst_raster>
+
+Description
+-----------
+
+The :program:`gdalenhance` utility enhances the contrast of raster 
+images using the GDAL library. It reads the input_file and writes 
+the output to output_file.
+
+.. program:: gdalenhance
+
+.. include:: options/help_and_help_general.rst
+
+.. option:: -of format
+
+ Select the output format. The default is GeoTIFF (GTiff).
+
+.. include:: options/co.rst
+
+.. include:: options/ot.rst
+
+.. option:: -equalize
+
+ Get source image histogram, and compute equalization luts from
+ it, apply lut to the source image.
+
+.. option:: -config <filename> 
+
+ Apply custom LUT(look up table) to enhance the contrast of the image.
+ The number of lines in the LUT file should be equal to the number of bands
+ of the images.
+ Exmaple of LUT file:
+
+.. code-block::
+
+ 1:Band 0.0:ScaleMin 1.0:ScaleMax
+ 2:Band 0.0:ScaleMin 1.0:ScaleMax
+ 3:Band 0.0:ScaleMin 1.0:ScaleMax
+
+Example
+--------
+
+.. code-block::
+
+ gdalenhance -equalize rgb.tif rgb_equalize_enhance.tif
+
+apply equalization histogram to enhance the contrast of the image.
+
+.. code-block::
+
+ gdalenhance -config enhance_config rgb.tif rgb_custom_enhance.tif
+
+apply custom LUT (look up-table) to enhance the contrast of the image.

doc/source/programs/index.rst

@@ -33,6 +33,7 @@ Raster programs
  gdalbuildvrt
  gdal_contour
  gdaldem
+ gdalenhance
  rgb2pct
  pct2rgb
  gdalattachpct
@@ -72,6 +73,7 @@ Raster programs
  - :ref:`gdalbuildvrt`: Builds a VRT from a list of datasets.
  - :ref:`gdal_contour`: Builds vector contour lines from a raster elevation model.
  - :ref:`gdaldem`: Tools to analyze and visualize DEMs.
+ - :ref: `gdalenhance`: Performs image enhancement on raster.
  - :ref:`rgb2pct`: Convert a 24bit RGB image to 8bit paletted.
  - :ref:`pct2rgb`: Convert an 8bit paletted image to 24bit RGB.
  - :ref:`gdalattachpct`: Attach a color table to a raster file from an input file.