Not sure this is the right stackexchange site but seems to be the place with the most question about Alfresco I can find so here goes.
Have Alfresco Community Edition 4.2.d installed on a RHEL5 64bit box (mainly default install bar using MySQL as a database locally). Uploading PDFs to the documentLibrary is fine and thumbnail previews and flash previews are generating. If the PDF has been processed by ABBYY OCR (which we have running on a separate server and is used to OCR scanned PDFs) then the flash preview generates fine but the thumbnail is incredibly dark and looks as if it has been attacked by a can of spray paint.
I initially thought it could be a ghostscript issue but have updated that to 9.14 and still getting this issue. I have also tried playing around with ImageMagik but I can't get a nice clear thumbnail to generate. I am guessing it is a switch in the convert command that Alfresco is using but I am struggling to work out a combination of switches that will work and then where Alfresco would store these parameters. Or indeed what switches are currently being used.
I was wondering if anyone had seen this behaviour before with ImageMagik previews in Alfresco 4.2.d? It seems something unique to PDFs that have been through the OCR process so I am guessing I will need to create a separate transformation for them at a later stage.
EDIT: So it was suggested that a later version of ImageMagick and GS should resolve it. I have therefore installed GS 9.14 and IM 6.8.9-0 (both compiled form source). Running the following from a command line:
convert /root/test1.pdf[0] /root/test1.png
results in a crystal clear image thumbnail preview. Thinking I was on to a winner I have amended the following lines in alfresco-global.properties to point to the system location of GS and IM:
img.root=/usr
img.dyn=${img.root}/lib
img.exe=${img.root}/bin/convert
img.gslib = /usr/local/share/ghostscript/9.14/lib/
and alfresco loads. However the thumbnail preview generated by Alfresco using the new version of IM and GS does not result in nice clean previews.
I am guessing that Alfresco is passing some command line switch during the conversion that is undoing the good work of the later versions of these programs. Does anyone know where the switches for thumbnail creation might be stored in Alfresco?
