# 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

ignoregamma : bool
  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.
quantize : int
  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.
interlaced : bool
  Save using Adam7 interlacing. Default False.