[gimp-web] content: update GIMP 2.10.22 news.

[Jehan <jehanp src gnome org>]

commit aaa901746fb7874660e3712efd9b2256a2b1968c
Author: Jehan <jehan girinstud io>
Date:   Sun Oct 4 17:28:26 2020 +0200

    content: update GIMP 2.10.22 news.
    
    Adding some screenshots and updating the text.

 .../gimp-palette-conversion.jpg                    | Bin 0 -> 265646 bytes
 .../heif-avif-high-bit-depth.jpg                   | Bin 0 -> 65798 bytes
 .../2020/2020-08_GIMP-2.10.22_Released/index.md    | 111 +++++++++++++++++----
 .../sample-merged-gegl-tool-options.jpg            | Bin 0 -> 159065 bytes
 4 files changed, 93 insertions(+), 18 deletions(-)
---
diff --git a/content/news/2020/2020-08_GIMP-2.10.22_Released/gimp-palette-conversion.jpg 
b/content/news/2020/2020-08_GIMP-2.10.22_Released/gimp-palette-conversion.jpg
new file mode 100644
index 00000000..23b9ff94
Binary files /dev/null and b/content/news/2020/2020-08_GIMP-2.10.22_Released/gimp-palette-conversion.jpg 
differ
diff --git a/content/news/2020/2020-08_GIMP-2.10.22_Released/heif-avif-high-bit-depth.jpg 
b/content/news/2020/2020-08_GIMP-2.10.22_Released/heif-avif-high-bit-depth.jpg
new file mode 100644
index 00000000..1ceddeb1
Binary files /dev/null and b/content/news/2020/2020-08_GIMP-2.10.22_Released/heif-avif-high-bit-depth.jpg 
differ
diff --git a/content/news/2020/2020-08_GIMP-2.10.22_Released/index.md 
b/content/news/2020/2020-08_GIMP-2.10.22_Released/index.md
index 6b0de15c..e7846205 100644
--- a/content/news/2020/2020-08_GIMP-2.10.22_Released/index.md
+++ b/content/news/2020/2020-08_GIMP-2.10.22_Released/index.md
@@ -28,15 +28,24 @@ format plug-ins.
 
 ### HEIF: improved HEIC and new AVIF support
 
-AVIF is the HEIF variant using AV1 compression (instead of HEIC in the
-same container format). This format was highly awaited as being an [open,
-royalty-free, video coding format](https://en.wikipedia.org/wiki/AV1)
-developed by the Alliance for Open Media.
+AVIF is the HEIF variant using AV1 compression (instead of HEVC in the
+same HEIF container format, which is the default and also called HEIC).
+This format was highly awaited as being an [open, royalty-free, video
+coding format](https://en.wikipedia.org/wiki/AV1) developed by the
+Alliance for Open Media.
 It is now supported by GIMP, both for import and export.
 
 Not only this, but HEIF files (both AV1 and HEIC) can now be imported
 and exported in high bit depth (10 and 12 bit per channel).
 
+<figure>
+<img src="{attach}heif-avif-high-bit-depth.jpg" alt="AVIF and high bit depth HEIF support"/>
+<figcaption>
+<em>GIMP 2.10.20 brings AVIF support, as well high-bit depth support.
+It will also import NCLX profiles and metadata.</em>
+</figcaption>
+</figure>
+
 And finally NCLX color profile and metadata will now be properly
 imported.
 
@@ -110,12 +119,49 @@ All filters implemented as GEGL operations now show a "*Sample merged*"
 checkbox in the Tool Options dockable (just below the "*Sample average*"
 option). This allows color picking visible colors when necessary.
 
+<figure>
+<img src="{attach}sample-merged-gegl-tool-options.jpg" alt="Sample merged in GEGL operations"/>
+<figcaption>
+<em>The new "Sample merged" options will allow to pick visible colors when relevant, for instance here with 
the "Colorize" operation.</em>
+</figcaption>
+</figure>
+
 ## Spyrogimp plug-in
 
 Spyrogimp (the official plug-in to draw spyrograph patterns) now works
 on Grayscale images too. Also its usage will now clutter less the undo
 history.
 
+## Improved indexed conversion
+
+This is actually a feature which came in with GIMP 2.10.20, but we
+forgot to mention it in the previous release note. So let's describe the
+changes here.
+
+The conversion to indexed image uses a median-cut algorithm to derive a
+suitable palette for the image. Such algorithm computes each index to be
+used as the average of colors in a 3D box in a color space, making the
+result value drift away from the extremes.
+This makes it nigh impossible to achieve pure white or black, even when
+the original image contained these colors, like in scans of printed
+documents and technical drawings.
+
+We now counteract the drift by snapping the whitest color to white and
+the blackest color to black if the resulting colors of median-cut are
+sufficiently close to white or black **and** if the original image
+already had some pure white or black.
+
+<figure>
+<img src="{attach}gimp-palette-conversion.jpg" alt="Comparison of palette creation"/>
+<figcaption>
+<em>Left is an original image in RGB, converted to a 6-palette indexed image in GIMP 2.10.18 (center) and 
2.10.20 or later (right).</em>
+</figcaption>
+</figure>
+
+*Note that the 2-color optimum palette case is special-cased not to use
+this modified algorithm as we already provide a dedicated "black and
+white (1-but) palette" option which would do the same thing.*
+
 # Configuration and defaults
 ## Sample merged default in Color Picker tool
 
@@ -215,35 +261,64 @@ format on GNU/Linux.
 
 ## GEGL and babl
 
-TODO
+As usual, GIMP release is accompanied by [babl](http://gegl.org/babl/)
+(0.1.78 and 0.1.80) and [GEGL](http://gegl.org/) (0.4.24 and 0.4.26)
+releases, with various bug fixes.
 
 ## Continuous Integration
 
 GIMP CI process now runs a `distcheck` step, hence producing a fully
-tested source tarball without human interaction.
+unit-tested source tarball without human interaction.
 
 Continuous builds of the development version (future GIMP 3) for Windows
 were already provided [since GIMP
 2.10.18](https://www.gimp.org/news/2020/02/24/gimp-2-10-18-released/#continuous-integration)
 but the downloadable archive was huge, containing many temporary files
-from the build process. We now implemented a new CI job with a
-slimmed-down and usable build. The following dynamic links will always
-return you the last successful development builds:
+from the build process and a wrapper to necessarily run at first launch.
+We now implemented a new CI job with a slimmed-down and hopefully usable
+build (if not please report, or better: send us patches!) and already
+fully set up with no first launch process. The idea came from the
+[Siril](http://www.siril.org/) project (astronomical image processing
+free software) after we helped them set up a cross-compilation CI,
+similar to ours, using [crossroad](https://pypi.org/project/crossroad/).
+A pretty good example of exchange between Free Software where some code
+goes from one project, to another where it is improved, then back to the
+original one. 🥳
+
+This will be very useful when asking people to test the development
+version as a lot of bugs are fixed on it (often just because the GTK+2
+toolkit is simply not maintained anymore whereas the development version
+using GTK+3 fixes the problem by itself). The following dynamic links
+will always return you the last successful development builds:
 
 * » [Last development build of GIMP for Windows
 64-bit](https://gitlab.gnome.org/GNOME/gimp/-/jobs/artifacts/master/download?job=win64-nightly) «
 * » [Last development build of GIMP for Windows
 32-bit](https://gitlab.gnome.org/GNOME/gimp/-/jobs/artifacts/master/download?job=win32-nightly) «
 
-These changes are all part of a more global work-in-progress to
-eventually automatize the release procedure, to be faster, easier and
-more trustworthy.
+*NOTE 0: test builds are for testing purpose only (as the name tells!).
+They have not been human-tested, it relies on very often modified
+development code and our automatic build process is still a bit young
+(which means there may even be bugs specific to the build). So do not
+use for production!*
+
+*NOTE 1: there are still a few known issues, such as missing GObject
+Introspection, i.e. that the Python 3/Javascript/Lua/Vala plug-ins won't
+work with this build (yet).*
+
+*Note 2: these builds are not provided with fancy installer nor any
+desktop integration (i.e. no shortcuts in menus, etc.). Just unzip the
+archive, and double-click `gimp.cmd` or `gimp-2.99.exe` files.*
+
+These changes are all part of a more global work-in-progress to improve
+development code testing as well as eventually automatize the release
+procedure, to be faster, easier and more trustworthy.
 
 # Contributors
 
-Contributors to this release are: TODO
+Contributors to this release are: Daniel Novomesky, David Russo, Elad Shahar, Ell, Jacob Boerema, Jehan, 
Liam Quin, Michael Natterer, Peter Oliver, luz.paz, sabri ünal, Sebastian Rasmussen, Simon McVittie, space 
pudim, Øyvind Kolås.
 
-Translators: TODO
+Translators: Alan Mortensen, Alexandre Prokoudine, Anders Jonsson, Andika Triwidada, Asier Sarasua 
Garmendia, Baurzhan Muftakhidinov, Boyuan Yang, Christian Kirbach, Daniel Mustieles, Jordi Mas, Julien 
Hardelin, Marco Ciampa, Milo Ivir, Piotr Drąg, Rodrigo Lledó, Sabri Ünal, sicklylife, Stephan Woidowski, Tim 
Sabsch, Yuri Chornoivan.
 
 We also thank lillolollo, nmat, and Michael Schumacher for triaging bug reports, and Julien Hardelin for 
updating the user manual.
 
@@ -276,10 +351,10 @@ During the same time span, specific work on the development version
   display resolutions).
 * Former Python 2 specific API (`pygimp`) has now been fully removed and
   all former Python plug-ins have been fully ported to Python 3 + new
-  GIMP 3 API (a work started over a year ago and now finished). The
-  new way to make Python plug-ins is streamlined, following the same
-  logics as for other supported languages (C/C++, Python 3, Lua, Vala
-  and Javascript so far).
+  GIMP 3 API (a work started over a year ago and now finished, with a
+  lot of help from Elad Shahar). The new way to make Python plug-ins is
+  streamlined, following the same logics as for other supported
+  languages (C/C++, Python 3, Lua, Vala and Javascript so far).
 * Some Wayland bug hunting done (still more to go).
 * GimpSpinScale styling improved and the new style is now unique (old
   non-compact style is not available anymore, unlike in GIMP 2.10.x).
diff --git a/content/news/2020/2020-08_GIMP-2.10.22_Released/sample-merged-gegl-tool-options.jpg 
b/content/news/2020/2020-08_GIMP-2.10.22_Released/sample-merged-gegl-tool-options.jpg
new file mode 100644
index 00000000..d8a38086
Binary files /dev/null and 
b/content/news/2020/2020-08_GIMP-2.10.22_Released/sample-merged-gegl-tool-options.jpg differ