| Extracted from Pike v7.8 release 700 at 2013-06-08.

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Image
Image.PNG

# Method Image.PNG.encode()

Method encode

  `string encode(Image.Image image)`
  `string encode(Image.Image image, mapping options)`

Description

  Encodes a PNG image.

Parameter `options`

  `"alpha" : Image.Image` | Use this image as alpha channel (Note: PNG alpha channel is grey. The values are calculated by (r+2g+b)/4.)
  `"palette" : Image.Colortable` | Use this as palette for pseudocolor encoding (Note: encoding with alpha channel and pseudocolor at the same time are not supported)
  `"zlevel" : int(0..9)` | The level of z-compression to be applied. Default is 8.
  `"zstrategy" : int` | The type of LZ77 strategy to be used. Possible values are Gz.DEFAULT_STRATEGY , Gz.FILTERED , Gz.HUFFMAN_ONLY , Gz.RLE , Gz.FIXED . Default is Gz.DEFAULT_STRATEGY .

See also

  __decode

Note

  Please read some about PNG files.