JPG optimization
Download jpegoptim from https://github.com/tjko/jpegoptim
git clone git@github.com:tjko/jpegoptim.git
Install jpegoptim
./configure
make
make strip
make install
Use jpegoptim
# compress one file
jpegoptim file.jpg
# compress multiple files
jpegoptim file.jpg file1.jpg file2.jpg
Compress image to around 50k
jpegoptim file.jpg -size=50k --strip-all
Compress a folder of images
cd FOLDER
jpegoptim --size=250k *.jpg
PNG optimization
Download optiPNG from http://optipng.sourceforge.net/
Install optiPNG
cd <folder>
./configure
make
make install
Use optiPNG
optipng logo.png
optipng *.png
Imagemagick
https://www.imagemagick.org/script/install-source.php
git clone git@github.com:ImageMagick/ImageMagick.git
$ cd ImageMagick-7.0.7
$ ./configure
$ make
sudo make install
sudo ldconfig /usr/local/lib
# test
/usr/local/bin/convert logo: logo.gif
Convert file
https://www.imagemagick.org/script/convert.php
magick convert rose.jpg rose.png
Convert and resize image
magick convert rose.jpg -resize 50% rose.png
Optimization
convert puzzle.jpg -sampling-factor 4:2:0 -strip -quality 85 -interlace JPEG -colorspace sRGB puzzle_converted.jpg