# Requirements

The package is built on PHP. PHP is a popular general-purpose scripting language that is especially suited to web development. As a consequence, the package can be installed and deployed on most server configurations.

  • PHP 7.2, or superior

The package also requires the installation of these image optimization tools:

  • gifsicle (opens new window)
    • -O3, Optimize output GIF animations for space, try several optimization methods.
  • jpegoptim (opens new window)
    • --strip-all, Strip all (Comment & Exif) markers from output file. (NOTE! by default only Comment & Exif markers are kept, everything else is discarded)
    • --all-progressive, Force all output files to be progressive.
    • --max=92, Sets the maximum image quality factor. This option will reduce quality of those source files that were saved using higher quality setting. While files that already have lower quality setting will be compressed using the lossless optimization method.
  • jpegtran (opens new window)
    • -optimize, perform optimization of entropy encoding parameters.
    • -progressive, create progressive JPEG file.
  • optipng (opens new window), PNG optimizer that recompresses image files to a smaller file size, without losing any information.
  • pngout (opens new window), it optimizes the file size of .PNG files losslessly.
  • pngquant (opens new window), the conversion reduces file sizes significantly (often as much as 70%) and preserves full alpha transparency.

If a tool is not installed, then the specific optimization step is ignored; and the process continues with the next available tool.

As an alternative, if the tools cannot be installed or you prefer to avoid the installation of tools, a Dockerfile is provided to build a Docker image to run the command xt-mio. In this case, Docker services must be available on the server.