Crop
Controls how the image is aligned.
Alignment position &a=
How the image should be aligned when &fit=cover
or &fit=contain
is set. The &w=
and &h=
parameters should also be specified.
Position-based
Controls the starting location of the crop. When &fit=contain
is set, it determines how the image is positioned inside its box.
Valid positions:
center
: defaulttop
right
bottom
left
top-left
bottom-left
bottom-right
top-right
For more information, please see the suggestion on our GitHub issue tracker: Issue #24 - Aligning.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&h=300&fit=cover&a=top">
![Alignment position](https://wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&h=300&fit=cover&a=top)
Focal point &a=focal
You can be more specific about the alignment using a focal point. This can be set using a horizontal (&fpx=
) and vertical (&fpy=
) offset decimal value (a float between 0.0
and 1.0
, inclusive). The default value is 0.5
, or the center of the image.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&h=300&fit=cover&a=focal&fpy=0.45">
![Focal point](https://wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&w=300&h=300&fit=cover&a=focal&fpy=0.45)
Smart crop &a=[entropy,attention]
An experimental strategy-based approach to crop the image by removing boring parts. This only works with &fit=cover
.
More info: Issue #90 - Add support for smart crop.
Valid strategies:
entropy
: focus on the region with the highest Shannon entropy.attention
: focus on the region with the highest luminance frequency, color saturation and presence of skin tones.
<img src="//wsrv.nl/?url=wsrv.nl/puppy.jpg&w=300&h=300&fit=cover&a=attention">
![Smart crop](https://wsrv.nl/?url=wsrv.nl/puppy.jpg&w=300&h=300&fit=cover&a=attention)
Rectangle crop &c[x,y,w,h]=
Crops the image to specific dimensions after any other resize operations.
Use percentage values (denoted by a value ending with %
) to crop a relative portion of the image.
TIP
You can use &precrop
, for a pre-resize crop behaviour. See Issue #176 - Combine cropping with resizing for more information.
<img src="//wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&cx=680&cy=500&cw=300&ch=300">
![Rectangle crop](https://wsrv.nl/?url=wsrv.nl/lichtenstein.jpg&cx=680&cy=500&cw=300&ch=300)
Trim &trim=
Trim "boring" pixels from all edges that contain values within a similarity of the top-left pixel. Trimming occurs before any resize operation. Use values between 1
and 254
to define a tolerance level to trim away similar color values. You also can specify just &trim
, which defaults to a tolerance level of 10
.
More info: Issue #39 - able to remove black/white whitespace.
<img src="//wsrv.nl/?url=wsrv.nl/transparency_demo.png&w=300&trim=10">
![Trim](https://wsrv.nl/?url=wsrv.nl/transparency_demo.png&w=300&trim=10)