(PHP 5 >= 5.5.0, PHP 7) Scale an image using the given new width and height

(PHP 4, PHP 5, PHP 7) Apply a gamma correction to a GD image

(PHP 4 >= 4.0.1, PHP 5, PHP 7) Create a new image from file or URL

(PHP 5 >= 5.2.2, PHP 7) Captures the whole screen

(PHP 4 >= 4.0.6, PHP 5, PHP 7) Set the style for line drawing

(PHP 4 >= 4.0.4, PHP 5, PHP 7) Create a new image from the image stream in the string

(PHP 5 >= 5.5.0, PHP 7) Concat two matrices (as in doing many ops in one go)

(PHP 4 >= 4.3.2, PHP 5, PHP 7) Should antialias functions be used or not

(PHP 4, PHP 5, PHP 7) Draw a string horizontally

(PHP 4 >= 4.3.0, PHP 5, PHP 7) Set the alpha blending flag to use the bundled libgd layering effects