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Code Issues Projects Releases Wiki Activity

Update notes for 2017-03-03

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Alan Orth
2017-03-03 18:40:38 +02:00
parent 644e443069
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@ -36,7 +36,7 @@
<p></p>
<ul>
<li>This results in discolored thumbnails, sRGB and CMYK:</li>
<li>This results in discolored thumbnails when compared to the original PDF, for example sRGB and CMYK:</li>
</ul>
<p><img src="https://alanorth.github.io/cgspace-notes/cgspace-notes/2017/03/thumbnail-srgb.jpg" alt="Thumbnail in sRGB colorspace" /></p>
@ -45,7 +45,29 @@
<ul>
<li>I filed an issue for the color space thing: <a href="https://jira.duraspace.org/browse/DS-3517">DS-3517</a></li>
&lt;/ul&gt;</description>
&lt;/ul&gt;
&lt;h2 id=&#34;2017-03-03&#34;&gt;2017-03-03&lt;/h2&gt;
&lt;ul&gt;
&lt;li&gt;I created a patch for DS-3517 and made a pull request against upstream &lt;code&gt;dspace-5_x&lt;/code&gt;: &lt;a href=&#34;https://github.com/DSpace/DSpace/pull/1669&#34;&gt;https://github.com/DSpace/DSpace/pull/1669&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;Looks like &lt;code&gt;-colorspace sRGB&lt;/code&gt; alone isn&amp;rsquo;t enough, we need to use profiles:&lt;/li&gt;
&lt;/ul&gt;
&lt;pre&gt;&lt;code&gt;$ convert -thumbnail 300x300 -flatten -profile /opt/brew/Cellar/ghostscript/9.20/share/ghostscript/9.20/iccprofiles/default_cmyk.icc -profile /opt/brew/Cellar/ghostscript/9.20/share/ghostscript/9.20/iccprofiles/default_rgb.icc alc_contrastes_desafios.pdf\[0\] alc_contrastes_desafios.pdf.jpg
&lt;/code&gt;&lt;/pre&gt;
&lt;ul&gt;
&lt;li&gt;This is a great resource describing the color stuff: &lt;a href=&#34;http://www.imagemagick.org/Usage/formats/#profiles&#34;&gt;http://www.imagemagick.org/Usage/formats/#profiles&lt;/a&gt;&lt;/li&gt;
&lt;li&gt;Somehow we need to detect the color system being used by the input file and handle each case differently&lt;/li&gt;
&lt;li&gt;This is trivial with &lt;code&gt;identify&lt;/code&gt; (even by the &lt;a href=&#34;http://im4java.sourceforge.net/api/org/im4java/core/IMOps.html#identify&#34;&gt;Java ImageMagick API&lt;/a&gt;):&lt;/li&gt;
&lt;/ul&gt;
&lt;pre&gt;&lt;code&gt;$ identify -format &#39;%r\n&#39; alc_contrastes_desafios.pdf\[0\]
DirectClass CMYK
$ identify -format &#39;%r\n&#39; Africa\ group\ of\ negotiators.pdf\[0\]
DirectClass sRGB Alpha
&lt;/code&gt;&lt;/pre&gt;</description>
</item>
<item>