# Adjustment
Perform operations similar to those in image-editing applications.
# Background &bg=
Sets the background color of the image. Supports a variety of color formats. In addition to the 140 color names supported by all modern browsers (listed here), it also accepts hexadecimal RGB and RBG alpha formats.
Valid hexadecimal formats:
- 3 digit RGB:
CCC - 4 digit ARGB (alpha):
5CCC - 6 digit RGB:
CCCCCC - 8 digit ARGB (alpha):
55CCCCCC
More info: Issue #81 - Background setting(opens new window).
# Blur &blur=
Adds a blur effect to the image. When used without a value (&blur), performs a fast, mild blur of the
output image. When a value is provided, performs a slower, more accurate Gaussian blur.
Use values between 0.3 and 1000, representing the sigma of the Gaussian mask, where sigma = 1 + radius / 2.
More info: Issue #69 - Allow blur transformation (with radius parameter)(opens new window).
# Contrast &con=
Adjusts the image contrast. Use values between -100 and +100, where 0 represents no change.
# Filter &filt=
Applies a filter effect to the image. Accepts greyscale, sepia, duotone or negate.
TIP
You can use &start and &stop to define the duotone colors. By default, it will use
&start=C83658 and
&stop=D8E74F.
# Gamma &gam=
Adjusts the image gamma. Use values between 1.0 and 3.0. The default value is 2.2, a suitable
approximation for sRGB images.
# Modulate &mod=New!
Transforms the image using brightness, saturation and hue rotation. Use &mod=[brightness multiplier], [saturation multiplier],[hue degrees] to define the below adjustments at once.
# Brightness &mod=
Adjusts the brightness of the image. A multiplier greater than 1 will increase brightness, while a multiplier less than 1 will decrease the brightness.
# Saturation &sat=
Adjusts the saturation of the image. A multiplier greater than 1 will increase saturation, while a multiplier less than 1 will decrease the saturation.
# Hue rotation &hue=
Applies a hue rotation to the image. A positive hue rotation increases the hue value, while a negative rotation decreases the hue value.
Values are given in degrees, there is no minimum or maximum value; &hue=N evaluates to N modulo
360.
# Sharpen &sharp=
Sharpen the image. Performs an accurate sharpen of the L channel in the LAB color space. Use in combination with
&sharpf= and &sharpj= to control the level of sharpening in "flat" and "jagged" areas.
# Tint &tint=New!
Tint the image using the provided chroma while preserving the image luminance. See here for the supported color formats.
← Orientation Format →









