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.
<img src="//wsrv.nl/?url=wsrv.nl/transparency_demo.png&w=400&bg=black">
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).
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&blur=5">
Contrast &con=
Adjusts the image contrast. Use values between -100 and +100, where 0 represents no change.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&con=25">
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.
<img src="//wsrv.nl/?url=wsrv.nl/zebra.jpg&w=300&h=300&fit=cover&a=focal&fpx=0.6&filt=duotone">
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.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&gam=3">
Modulate &mod=
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.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&mod=2">
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.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&sat=0.5">
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.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&hue=90">
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.
Use values between 0.000001 and 10, representing the sigma of the Gaussian mask, where sigma = 1 + radius / 2. When used without parameters, performs a fast, mild sharpen of the output image.
The level of sharpening to apply to "flat" (&sharpf=) and "jagged" (&sharpj=) areas needs to be given in the range of 0 and 1000000.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&sharp=3">
Tint &tint=
Tint the image using the provided chroma while preserving the image luminance. See here for the supported color formats.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&tint=red">