openCL slows down complex command

Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
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adam7288
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Joined: 2018-09-15T19:13:46-07:00
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openCL slows down complex command

Post by adam7288 » 2019-05-09T20:56:21-07:00

Hello - I clearly am in over my head. Before I invest in multi core CPU's to address my needs, I want to make sure I there is no way to speed up the following command (for processing images to fax format):

convert <filename> -auto-orient -background "#FFFFFF" -resize 1728x2200 -gravity center -extent 1728x2200 -monochrome -threshold 80% -despeckle -depth 1 -set units PixelsPerInch -density 204x196 -compress FAX -format tiff <outputfilename>

When I compile for OpenCL on a newish (Geforce 960) gpu, the command executes 5x slower. Would be great if I could speed this up using gpu power instead of buying lots of cpus.

adam7288
Posts: 6
Joined: 2018-09-15T19:13:46-07:00
Authentication code: 1152

Re: openCL slows down complex command

Post by adam7288 » 2019-05-09T21:49:59-07:00

Update: I compiled with debug on.

Once I compile for "release" the result is that OpenCL does not get used in the above command. Any way to have imagemagick get used to speed it up?

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