Applies an image filter to the image.
The preset options are:
INVERT
Inverts the colors in the image. No parameter is used.
GRAY
Converts the image to grayscale. No parameter is used.
THRESHOLD
Converts the image to black and white. Pixels with a grayscale value above a given threshold are converted to white. The rest are converted to black. The threshold must be between 0.0 (black) and 1.0 (white). If no value is specified, 0.5 is used.
OPAQUE
Sets the alpha channel to be entirely opaque. No parameter is used.
POSTERIZE
Limits the number of colors in the image. Each color channel is limited to the number of colors specified. Values between 2 and 255 are valid, but results are most noticeable with lower values. The default value is 4.
BLUR
Blurs the image. The level of blurring is specified by a blur radius. Larger values increase the blur. The default value is 4. A gaussian blur is used in P2D
mode. A box blur is used in WEBGL
mode.
ERODE
Reduces the light areas. No parameter is used.
DILATE
Increases the light areas. No parameter is used.
Ejemplos
Sintaxis
filter(filterType, [filterParam])
Parámetros
either THRESHOLD, GRAY, OPAQUE, INVERT, POSTERIZE, ERODE, DILATE or BLUR.
parameter unique to each filter.