Monthly Archives: September 2012

Can’t plot or use imagesc in Octave

If you get a lot of gnuplot errors when trying to plot or use imagesc or imshow in Octave, Try installing gnuplot-x11 in Ubuntu, type at Terminal: sudo apt-get install gnuplot-x11

ImageMagick suggested compile options

These options were used to compile ImageMagick 6.7.9-3 and 6.8.0-4. Before compiling, I urge you to ensure libjasper-dev is installed, so that you can manipulate JPEG2000 images. Try typing: sudo apt-get install libjasper-dev libpng-dev Then, type: ./configure –with-modules –with-gslib –with-wmf –with-perl –with-rsvg –with-gvc Note: you can add HDRI by adding this option above: –enable-hdri […]

Compiled program, and now “file or directory not found” after “make install”

Sometimes a compiled program puts itself (or a soft link) on /usr/local/bin or a similar directory listed under echo $PATH, but it won’t actually be found until you log off and on (or worst case, reboot). Try that if your newly compiled program won’t run.

Compute & Display Histogram with Imagemagick

In Terminal/Command Prompt, type: convert input.jpg histogram:png:- | display jpg:- where input.jpg is an image in ANY format that you want to display the histogram