Installation:
# Needed for processing JPG/PNG files
apt-get install libjpeg62 libpng
apt-get install imagemagickTroubleshooting:
Need to install imagemagick:
Validation failed: Avatar Failed to manipulate with MiniMagick, maybe it is not an image? Original Error: ImageMagick/GraphicsMagick is not installed
libpng/libjpeg not installed:
A NoMethodError occurred in avatar#update:
private method `format' called for #<MiniMagick::Tool::Identify:0x007f8914a9afe8>