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Ah, it seems the attached images from my last email were too big for
the email list.<br>
Sending again without the images...<br>
<br>
<div class="moz-cite-prefix">On 4/01/2015 12:22 pm, Cameron Shorter
wrote:<br>
</div>
<blockquote
cite="mid:CABqeU+gAy6AwtC_rL9NWk2qv9sE7vSF2GijtmmELobA_xxS6-w@mail.gmail.com"
type="cite">
<div dir="ltr">
<div>
<div><br>
</div>
Angelos noticed that the size of the images within our docs
directory seems to have increased recently as quickstarts are
getting updated.<br>
In our recent IRC meeting, it was suggested that maybe we
could reduce image sizes, either by compressing png images
(without loss of quality) or by switching to jpg images (with
minimal loss of quality).<br>
<br>
So I've done some tests of the image directory under a few
different scenarios, using the command-line imagemagic to
convert images. Command used:<br>
convert -resize 800x600 -quality 85 tilemill_projectinfo.png
tilemill_projectinfo.jpg; rm tilemill_projectinfo.png<br>
<br>
Directory sizes as below.<br>
<br>
</div>
<div>My conclusions:<br>
</div>
<div>* Yes, we can save some space from converting PNG to JPG,
but it would result in degradation of image quality, so we
should keep source images in original PNG format.<br>
</div>
<div>* For the docs copied onto the ISO image, we could write a
script which converts png->jpg (with reduced quality), but
keep high quality images on our website at <a
moz-do-not-send="true" href="http://live.osgeo.org">http://live.osgeo.org</a>
. (This shouldn't be our first choice, as ideally our website
and iso should have the same docs, and we should try to keep
the docs on the iso at best quality available).<br>
</div>
<div><br>
du -sh trunk/doc/images*<br>
161M images-osgeolive8.0 (Not sure why last release was so
big)<br>
90M images-osgeolive8.5a3 (current osgeolive8.5a3
directory)<br>
89M images_optipng (compress png to png. Not much to save.
using optipng -o5)<br>
64M images_jpg (png to jpg, no compression)<br>
34M images_50jpg (png to jpg, 50% compression)<br>
52M images_85jpg (png to jpg, 85% compression)<br>
45M images_85jpg800x600 (png to jpg, 85% compression,
resize 1024x768 screenshots to 800x600)<br>
<br>
</div>
<div>The level of image degradation from compression seems to
vary between screen shots.<br>
</div>
<div>The GeoNetwork images don't look too good when compressed:<br>
<br>
</div>
<div>Original PNG image:<br>
</div>
<div><image><br>
<br>
</div>
<div>Compressed 85% JPG:<br>
<image><br>
</div>
<div><br>
</div>
<div>Compressed 50% JPG:<br>
<image><br>
</div>
<div><br>
The GRASS images seem to compress better:<br>
</div>
<div>Original PNG:<br>
<image><br>
</div>
<div><br>
<br>
Compressed 85% JPG:<br>
<image><br>
<br>
<br>
Compressed 50% JPG:<br>
<image><br>
<br>
<br>
<br>
<div>
<div dir="ltr">
<div>-- </div>
<div>Cameron Shorter,</div>
<div>Software and Data Solutions Manager</div>
<div>LISAsoft</div>
<div>Suite 112, Jones Bay Wharf,</div>
<div>26 - 32 Pirrama Rd, Pyrmont NSW 2009</div>
<div><br>
</div>
<div>P <a moz-do-not-send="true"
href="tel:%2B61%202%209009%205000"
value="+61290095000" target="_blank">+61 2 9009 5000</a>,
W <a moz-do-not-send="true"
href="http://www.lisasoft.com" target="_blank">www.lisasoft.com</a>,
F <a moz-do-not-send="true"
href="tel:%2B61%202%209009%205099"
value="+61290095099" target="_blank">+61 2 9009 5099</a></div>
</div>
</div>
</div>
</div>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Cameron Shorter,
Software and Data Solutions Manager
LISAsoft
Suite 112, Jones Bay Wharf,
26 - 32 Pirrama Rd, Pyrmont NSW 2009
P +61 2 9009 5000, W <a class="moz-txt-link-abbreviated" href="http://www.lisasoft.com">www.lisasoft.com</a>, F +61 2 9009 5099</pre>
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