imagecropauto
GdImage$image,
[int$mode = IMG_CROP_DEFAULT],
[float$threshold = 0.5],
[int$color = -1]
): GdImage|false
Automatically crops an image according to the given mode.
Parameters
- image
A GdImage object, returned by one of the image creation functions, such as imagecreatetruecolor.
- mode
-
One of the following constants:
- IMG_CROP_DEFAULT
-
Same as IMG_CROP_TRANSPARENT. Before PHP 7.4.0, the bundled libgd fell back to IMG_CROP_SIDES, if the image had no transparent color.
- IMG_CROP_TRANSPARENT
-
Crops out a transparent background.
- IMG_CROP_BLACK
-
Crops out a black background.
- IMG_CROP_WHITE
-
Crops out a white background.
- IMG_CROP_SIDES
-
Uses the 4 corners of the image to attempt to detect the background to crop.
- IMG_CROP_THRESHOLD
-
Crops an image using the given threshold and color.
- threshold
-
Specifies the tolerance in percent to be used while comparing the image color and the color to crop. The method used to calculate the color difference is based on the color distance in the RGB(a) cube.
Used only in IMG_CROP_THRESHOLD mode.
Note:
Before PHP 7.4.0, the bundled libgd used a somewhat different algorithm, so the same threshold yielded different results for system and bundled libgd.
- color
-
Either an RGB color value or a palette index.
Used only in IMG_CROP_THRESHOLD mode.
Return Values
Returns a cropped image object on success or false on failure. If the complete image was cropped, imagecrop returns false.
Changelog
| Version | Description |
| 8.0.0 | image expects a GdImage instance now; previously, a resource was expected. |
| 8.0.0 | On success, this function returns a GDImage instance now; previously, a resource was returned. |
| 7.4.0 | The behavior of imagecropauto() in the bundled libgd has been synced with that of system libgd: IMG_CROP_DEFAULT no longer falls back to IMG_CROP_SIDES and threshold-cropping now uses the same algorithm as system libgd. |
| 7.4.0 | The default value of mode has been changed to IMG_CROP_AUTO. Formerly, the default value has been -1 which corresponds to IMG_CROP_DEFAULT, but passing -1 is now deprecated. |