Color quantization. Specifies color-quantization attributes for GIF output conversion.
quantize= *
type*[, *
dither*[, *
numColors*[, *
colorList*]]]
type |
{adaptive|web|mac} Specifies the palette type. Set to adaptive to calculate an optimal palette for the image. Set to web or mac to choose a pre-defined palette.
Note: The mac pallet type is only supported for GIF and PNG8 formats but not for GIF-Alpha and PNG8-Alpha formats. |
dither |
{diffuse|off} Specifies the dithering options. Set to diffuse for Floyd-Steinberg error diffusion Set to off to disable dithering. |
numColors |
Number of output colors (2-256) Specifies how many colors are included in the adaptive palette. |
colorList |
A comma-separated list of forced RGB colors in hex6 format Lets you specify colors to include in an adaptive palette. If the number of colors specified is less than numColors , additional colors are calculated based on the image content. |
Request attribute. Applies regardless of current layer setting. Used only if fmt=gif
, fmt=gif-alpha
, fmt=png8
, or fmt=png8-alpha
. Ignored otherwise.
The colors specified with colorList
must consist of RGB values in hex6 format (see color without 0x
prefix. No other color specifiers are permitted. numColors
must be between 2-256.
quantize=adaptive,diffuse,256
Generate a GIF thumbnail using the web
palette and no dithering:
http:// *
server*/myRootId/myImageId?req=tmb&fmt=gif&quantize=web,off
Convert image to a bi-tonal GIF with key-color transparency and force colors to black and white:
http:// *
server*/myRootId/myImageId?fmt=gif-alpha&wid=100&quantize=adaptive,off,2,000000,ffffff