Sometimes (e.g. newspaper or compressing images) we have to reduce depth of our image to only 1 bit. We can do it simply by applying thresholding:
But the result is usually not satisfactory for us – it has large regions of the same color.
There is a better idea than thresholding when it comes to monochromatic images:
1. Take original image:
2. Apply gaussian noise:
3. Do thresholding:
After this procedure we have an image that creates illusion that it has more than 1 bit depth. It’s so called dithering.
I’ve found this idea in “Practical signal processing” written by Mark Owen.
I want to present 3 algorithms of computing Fibonacci numbers written in Haskell: exponential, linear and logarithmic.
1. When I use nautilus I’d like to type addresses by hand. In several Gnome themes this option is disabled. You can fix it:
- Launch gconf-editor
- Go to apps/nautilus/preferences
- Check always_use_location_entry
2. After updating Firestarter stops displaying information about blocked connections.
In order to fix:
- Open /etc/rsyslog.d/50-default.conf
-
Uncomment there:
#*.=info;*.=notice;*.=warn;\
# auth,authpriv.none;\
# cron,daemon.none;\
# mail,news.none -/var/log/messages
- Type sudo service rsyslog restart
3. In Gnome Unity some tray icons (like Firefox, QuickSynergy or Kadu) are not diplayed.
Type:
gsettings set com.canonical.Unity.Panel systray-whitelist "['all']" unity --replace