This useful web application allows you to pick colors from an image either by uploading it or by giving its url. This was very useful when writing an article.
Researchers at Caltech made the animations below which show the seasonal deformation and subsidence of Earth’s surface, respectively, as a result of groundwater extraction and refilling. This occurs when soil and earth layers are compacted and undergo subsidence due to the decrease of upward hydrostatic pressure balancing the weight of the layers.
Surface deformation and subsidence of Earth’s surface is measured using Interferometric Synthetic Aperture Radar (ISAR). ISAR is also used for natural hazard assessment. This includes applications to regions of volcanic, tectonic (e.g. faults and mountains), and construction activities.
source: Caltech
A few commands I use frequently but sometimes forget.
pdftk *.pdf cat output out.pdf
convert -density 150 input.pdf -quality 90 output.png
mogrify -resize 640x480 *.{png|jpeg}
convert input.png -crop 0x4000 output.png
convert -delay 10 -loop 0 *.png animation.gif
