Bildfunktioner
Image Filters
See images.Filter for how to apply these filters to an image.
Brightness
Syntax
images.Brightness PERCENTAGE
Brightness creates a filter that changes the brightness of an image. The percentage parameter must be in range (-100, 100).
ColorBalance
Syntax
images.ColorBalance PERCENTAGERED PERCENTAGEGREEN PERCENTAGEBLUE
ColorBalance creates a filter that changes the color balance of an image. The percentage parameters for each color channel (red, green, blue) must be in range (-100, 500).
Colorize
Syntax
images.Colorize HUE SATURATION PERCENTAGE
Colorize creates a filter that produces a colorized version of an image. The hue parameter is the angle on the color wheel, typically in range (0, 360). The saturation parameter must be in range (0, 100). The percentage parameter specifies the strength of the effect, it must be in range (0, 100).
Contrast
Syntax
images.Contrast PERCENTAGE
Contrast creates a filter that changes the contrast of an image. The percentage parameter must be in range (-100, 100).
Gamma
Syntax
images.Gamma GAMMA
Gamma creates a filter that performs a gamma correction on an image. The gamma parameter must be positive. Gamma = 1 gives the original image. Gamma less than 1 darkens the image and gamma greater than 1 lightens it.
GaussianBlur
Syntax
images.GaussianBlur SIGMA
GaussianBlur creates a filter that applies a gaussian blur to an image.
Grayscale
Syntax
images.Grayscale
Grayscale creates a filter that produces a grayscale version of an image.
Hue
Syntax
images.Hue SHIFT
Hue creates a filter that rotates the hue of an image. The hue angle shift is typically in range -180 to 180.
Invert
Syntax
images.Invert
Invert creates a filter that negates the colors of an image.
Pixelate
Syntax
images.Pixelate SIZE
Pixelate creates a filter that applies a pixelation effect to an image.
Saturation
Syntax
images.Saturation PERCENTAGE
Saturation creates a filter that changes the saturation of an image.
Sepia
Syntax
images.Sepia PERCENTAGE
Sepia creates a filter that produces a sepia-toned version of an image.
Sigmoid
Syntax
images.Sigmoid MIDPOINT FACTOR
Sigmoid creates a filter that changes the contrast of an image using a sigmoidal function and returns the adjusted image. It’s a non-linear contrast change useful for photo adjustments as it preserves highlight and shadow detail.
UnsharpMask
Syntax
images.UnsharpMask SIGMA AMOUNT THRESHOLD
UnsharpMask creates a filter that sharpens an image. The sigma parameter is used in a gaussian function and affects the radius of effect. Sigma must be positive. Sharpen radius roughly equals 3 * sigma. The amount parameter controls how much darker and how much lighter the edge borders become. Typically between 0.5 and 1.5. The threshold parameter controls the minimum brightness change that will be sharpened. Typically between 0 and 0.05.
Other Functions
Filter
Syntax
IMAGE | images.Filter FILTERS…
Can be used to apply a set of filters to an image:
{{ $img := $img | images.Filter (images.GaussianBlur 6) (images.Pixelate 8) }}
Also see the Filter Method.
ImageConfig
Parses the image and returns the height, width, and color model.
Syntax
images.ImageConfig PATH
{{ with (imageConfig "favicon.ico") }}
favicon.ico: {{.Width}} x {{.Height}}
{{ end }}