Add notes for 2018-12-03

content/posts/2018-12.md

@@ -80,4 +80,61 @@ or(
 )
 ```
 
+## 2018-12-03
+
+- I looked at the DSpace Ghostscript issue more and it seems to only affect certain PDFs...
+- I can successfully generate a thumbnail for another recent item ([10568/98394](https://hdl.handle.net/10568/98394)), but not for [10568/98930](https://hdl.handle.net/10568/98390)
+- Even manually on my Arch Linux desktop with ghostscript 9.26-1 and the `pngalpha` device, I can generate a thumbnail for the first one (10568/98394):
+
+```
+$ gs -q -dQUIET -dSAFER -dBATCH -dNOPAUSE -dNOPROMPT -dMaxBitmap=500000000 -dAlignToPixels=0 -dGridFitTT=2 -sDEVICE=pngalpha -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -r72x72 -dFirstPage=1 -dLastPage=1 -sOutputFile=/tmp/out%d -f/home/aorth/Desktop/Info\ Note\ Mainstreaming\ gender\ and\ social\ differentiation\ into\ CCAFS\ research\ activities\ in\ West\ Africa-converted.pdf
+```
+
+- So it seems to be something about the PDFs themselves, perhaps related to alpha support?
+- The first item (10568/98394) has the following information:
+
+```
+$ identify Info\ Note\ Mainstreaming\ gender\ and\ social\ differentiation\ into\ CCAFS\ research\ activities\ in\ West\ Africa-converted.pdf\[0\]
+Info Note Mainstreaming gender and social differentiation into CCAFS research activities in West Africa-converted.pdf[0]=>Info Note Mainstreaming gender and social differentiation into CCAFS research activities in West Africa-converted.pdf PDF 595x841 595x841+0+0 16-bit sRGB 107443B 0.000u 0:00.000
+identify: CorruptImageProfile `xmp' @ warning/profile.c/SetImageProfileInternal/1746.
+```
+
+- And wow, I can't even run ImageMagick's `identify` on the first page of the second item (10568/98930):
+
+```
+$ identify Food\ safety\ Kenya\ fruits.pdf\[0\]
+zsh: abort (core dumped)  identify Food\ safety\ Kenya\ fruits.pdf\[0\]
+```
+
+- But with GraphicsMagick's `identify` it works:
+
+```
+$ gm identify Food\ safety\ Kenya\ fruits.pdf\[0\]
+DEBUG: FC_WEIGHT didn't match
+Food safety Kenya fruits.pdf PDF 612x792+0+0 DirectClass 8-bit 1.4Mi 0.000u 0m:0.000002s
+```
+
+- Interesting that ImageMagick's `identify` *does* work if you do not specify a page, perhaps as [alluded to in the recent Ghostscript bug report](https://bugs.ghostscript.com/show_bug.cgi?id=699815):
+
+```
+$ identify Food\ safety\ Kenya\ fruits.pdf
+Food safety Kenya fruits.pdf[0] PDF 612x792 612x792+0+0 16-bit sRGB 64626B 0.010u 0:00.009
+Food safety Kenya fruits.pdf[1] PDF 612x792 612x792+0+0 16-bit sRGB 64626B 0.010u 0:00.009
+Food safety Kenya fruits.pdf[2] PDF 612x792 612x792+0+0 16-bit sRGB 64626B 0.010u 0:00.009
+Food safety Kenya fruits.pdf[3] PDF 612x792 612x792+0+0 16-bit sRGB 64626B 0.010u 0:00.009
+Food safety Kenya fruits.pdf[4] PDF 612x792 612x792+0+0 16-bit sRGB 64626B 0.010u 0:00.009
+identify: CorruptImageProfile `xmp' @ warning/profile.c/SetImageProfileInternal/1746.
+```
+
+- As I expected, ImageMagick cannot generate a thumbnail, but GraphicsMagick can (though it looks like crap):
+
+```
+$ convert Food\ safety\ Kenya\ fruits.pdf\[0\] -thumbnail 600x600 -flatten Food\ safety\ Kenya\ fruits.pdf.jpg
+zsh: abort (core dumped)  convert Food\ safety\ Kenya\ fruits.pdf\[0\] -thumbnail 600x600 -flatten
+$ gm convert Food\ safety\ Kenya\ fruits.pdf\[0\] -thumbnail 600x600 -flatten Food\ safety\ Kenya\ fruits.pdf.jpg
+DEBUG: FC_WEIGHT didn't match
+```
+
+- I inspected the troublesome PDF using [jhove](http://jhove.openpreservation.org/) and noticed that it is using `ISO PDF/A-1, Level B` and the other one doesn't list a profile, though I don't think this is relevant
+
 <!-- vim: set sw=2 ts=2: -->

docs/2018-12/index.html

@@ -21,7 +21,7 @@ I noticed that there is another issue with PDF thumbnails on CGSpace, and I see
 " />
 <meta property="og:type" content="article" />
 <meta property="og:url" content="https://alanorth.github.io/cgspace-notes/2018-12/" /><meta property="article:published_time" content="2018-12-02T02:09:30&#43;02:00"/>
-<meta property="article:modified_time" content="2018-12-02T10:57:41&#43;02:00"/>
+<meta property="article:modified_time" content="2018-12-02T17:55:32&#43;02:00"/>
 
 <meta name="twitter:card" content="summary"/>
 <meta name="twitter:title" content="December, 2018"/>
@@ -48,9 +48,9 @@ I noticed that there is another issue with PDF thumbnails on CGSpace, and I see
   "@type": "BlogPosting",
   "headline": "December, 2018",
   "url": "https://alanorth.github.io/cgspace-notes/2018-12/",
-  "wordCount": "463",
+  "wordCount": "875",
   "datePublished": "2018-12-02T02:09:30&#43;02:00",
-  "dateModified": "2018-12-02T10:57:41&#43;02:00",
+  "dateModified": "2018-12-02T17:55:32&#43;02:00",
   "author": {
     "@type": "Person",
     "name": "Alan Orth"
@@ -200,6 +200,71 @@ DEBUG: FC_WEIGHT didn't match
 )
 </code></pre>
 
+<h2 id="2018-12-03">2018-12-03</h2>
+
+<ul>
+<li>I looked at the DSpace Ghostscript issue more and it seems to only affect certain PDFs&hellip;</li>
+<li>I can successfully generate a thumbnail for another recent item (<a href="https://hdl.handle.net/10568/98394"><sup>10568</sup>&frasl;<sub>98394</sub></a>), but not for <a href="https://hdl.handle.net/10568/98390"><sup>10568</sup>&frasl;<sub>98930</sub></a></li>
+<li>Even manually on my Arch Linux desktop with ghostscript 9.26-1 and the <code>pngalpha</code> device, I can generate a thumbnail for the first one (<sup>10568</sup>&frasl;<sub>98394</sub>):</li>
+</ul>
+
+<pre><code>$ gs -q -dQUIET -dSAFER -dBATCH -dNOPAUSE -dNOPROMPT -dMaxBitmap=500000000 -dAlignToPixels=0 -dGridFitTT=2 -sDEVICE=pngalpha -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -r72x72 -dFirstPage=1 -dLastPage=1 -sOutputFile=/tmp/out%d -f/home/aorth/Desktop/Info\ Note\ Mainstreaming\ gender\ and\ social\ differentiation\ into\ CCAFS\ research\ activities\ in\ West\ Africa-converted.pdf
+</code></pre>
+
+<ul>
+<li>So it seems to be something about the PDFs themselves, perhaps related to alpha support?</li>
+<li>The first item (<sup>10568</sup>&frasl;<sub>98394</sub>) has the following information:</li>
+</ul>
+
+<pre><code>$ identify Info\ Note\ Mainstreaming\ gender\ and\ social\ differentiation\ into\ CCAFS\ research\ activities\ in\ West\ Africa-converted.pdf\[0\]
+Info Note Mainstreaming gender and social differentiation into CCAFS research activities in West Africa-converted.pdf[0]=&gt;Info Note Mainstreaming gender and social differentiation into CCAFS research activities in West Africa-converted.pdf PDF 595x841 595x841+0+0 16-bit sRGB 107443B 0.000u 0:00.000
+identify: CorruptImageProfile `xmp' @ warning/profile.c/SetImageProfileInternal/1746.
+</code></pre>
+
+<ul>
+<li>And wow, I can&rsquo;t even run ImageMagick&rsquo;s <code>identify</code> on the first page of the second item (<sup>10568</sup>&frasl;<sub>98930</sub>):</li>
+</ul>
+
+<pre><code>$ identify Food\ safety\ Kenya\ fruits.pdf\[0\]
+zsh: abort (core dumped)  identify Food\ safety\ Kenya\ fruits.pdf\[0\]
+</code></pre>
+
+<ul>
+<li>But with GraphicsMagick&rsquo;s <code>identify</code> it works:</li>
+</ul>
+
+<pre><code>$ gm identify Food\ safety\ Kenya\ fruits.pdf\[0\]
+DEBUG: FC_WEIGHT didn't match
+Food safety Kenya fruits.pdf PDF 612x792+0+0 DirectClass 8-bit 1.4Mi 0.000u 0m:0.000002s
+</code></pre>
+
+<ul>
+<li>Interesting that ImageMagick&rsquo;s <code>identify</code> <em>does</em> work if you do not specify a page, perhaps as <a href="https://bugs.ghostscript.com/show_bug.cgi?id=699815">alluded to in the recent Ghostscript bug report</a>:</li>
+</ul>
+
+<pre><code>$ identify Food\ safety\ Kenya\ fruits.pdf
+Food safety Kenya fruits.pdf[0] PDF 612x792 612x792+0+0 16-bit sRGB 64626B 0.010u 0:00.009
+Food safety Kenya fruits.pdf[1] PDF 612x792 612x792+0+0 16-bit sRGB 64626B 0.010u 0:00.009
+Food safety Kenya fruits.pdf[2] PDF 612x792 612x792+0+0 16-bit sRGB 64626B 0.010u 0:00.009
+Food safety Kenya fruits.pdf[3] PDF 612x792 612x792+0+0 16-bit sRGB 64626B 0.010u 0:00.009
+Food safety Kenya fruits.pdf[4] PDF 612x792 612x792+0+0 16-bit sRGB 64626B 0.010u 0:00.009
+identify: CorruptImageProfile `xmp' @ warning/profile.c/SetImageProfileInternal/1746.
+</code></pre>
+
+<ul>
+<li>As I expected, ImageMagick cannot generate a thumbnail, but GraphicsMagick can (though it looks like crap):</li>
+</ul>
+
+<pre><code>$ convert Food\ safety\ Kenya\ fruits.pdf\[0\] -thumbnail 600x600 -flatten Food\ safety\ Kenya\ fruits.pdf.jpg
+zsh: abort (core dumped)  convert Food\ safety\ Kenya\ fruits.pdf\[0\] -thumbnail 600x600 -flatten
+$ gm convert Food\ safety\ Kenya\ fruits.pdf\[0\] -thumbnail 600x600 -flatten Food\ safety\ Kenya\ fruits.pdf.jpg
+DEBUG: FC_WEIGHT didn't match
+</code></pre>
+
+<ul>
+<li>I inspected the troublesome PDF using <a href="http://jhove.openpreservation.org/">jhove</a> and noticed that it is using <code>ISO PDF/A-1, Level B</code> and the other one doesn&rsquo;t list a profile, though I don&rsquo;t think this is relevant</li>
+</ul>
+
 <!-- vim: set sw=2 ts=2: -->
 
   

docs/sitemap.xml

@@ -4,7 +4,7 @@
   
   <url>
     <loc>https://alanorth.github.io/cgspace-notes/2018-12/</loc>
-    <lastmod>2018-12-02T10:57:41+02:00</lastmod>
+    <lastmod>2018-12-02T17:55:32+02:00</lastmod>
   </url>
   
   <url>
@@ -199,7 +199,7 @@
   
   <url>
     <loc>https://alanorth.github.io/cgspace-notes/</loc>
-    <lastmod>2018-12-02T10:57:41+02:00</lastmod>
+    <lastmod>2018-12-02T17:55:32+02:00</lastmod>
     <priority>0</priority>
   </url>
   
@@ -210,7 +210,7 @@
   
   <url>
     <loc>https://alanorth.github.io/cgspace-notes/tags/notes/</loc>
-    <lastmod>2018-12-02T10:57:41+02:00</lastmod>
+    <lastmod>2018-12-02T17:55:32+02:00</lastmod>
     <priority>0</priority>
   </url>
   
@@ -222,13 +222,13 @@
   
   <url>
     <loc>https://alanorth.github.io/cgspace-notes/posts/</loc>
-    <lastmod>2018-12-02T10:57:41+02:00</lastmod>
+    <lastmod>2018-12-02T17:55:32+02:00</lastmod>
     <priority>0</priority>
   </url>
   
   <url>
     <loc>https://alanorth.github.io/cgspace-notes/tags/</loc>
-    <lastmod>2018-12-02T10:57:41+02:00</lastmod>
+    <lastmod>2018-12-02T17:55:32+02:00</lastmod>
     <priority>0</priority>
   </url>