# oxipng

> Losslessly improve compression of PNG files.
> More information: <https://github.com/shssoichiro/oxipng>.

- Compress a PNG file (overwrites the file by default):

`oxipng {{path/to/file.png}}`

- Compress a PNG file and save the output to a new file:

`oxipng --out {{path/to/output.png}} {{path/to/file.png}}`

- Compress all PNG files in the current directory using multiple threads:

`oxipng "*.png"`

- Compress a file with a set optimization level (default is 2):

`oxipng --opt {{0|1|2|3|4|5|6|max}} {{path/to/file.png}}`

- Set the PNG interlacing type (`0` removes interlacing, `1` applies Adam7 interlacing, `keep` preserves existing interlacing; default is `0`):

`oxipng --interlace {{0|1|keep}} {{path/to/file.png}}`

- Perform additional optimization on images with an alpha channel:

`oxipng --alpha {{path/to/file.png}}`

- Use the much slower but stronger Zopfli compressor with max optimization:

`oxipng --zopfli --opt max {{path/to/file.png}}`

- Strip all non-critical metadata chunks:

`oxipng --strip all {{path/to/file.png}}`