# PNG-FI Portable Network Graphics

Extensions: `.png`

A PNG format based on the Freeimage library.

This format supports grayscale, RGB and RGBA images.

The freeimage plugin requires a freeimage binary. If this binary not available on the system, it can be downloaded manually from <https://github.com/imageio/imageio-binaries> by either

- the command line script `imageio_download_bin freeimage`

- the Python method `imageio.plugins.freeimage.download()`

## Parameters for reading

ignoregammabool

  Avoid gamma correction. Default True.

## Parameters for saving

compression{0, 1, 6, 9}

  The compression factor. Higher factors result in more compression at the cost of speed. Note that PNG compression is always lossless. Default 9.

quantizeint

  If specified, turn the given RGB or RGBA image in a paletted image for more efficient storage. The value should be between 2 and 256. If the value of 0 the image is not quantized.

interlacedbool

  Save using Adam7 interlacing. Default False.