(PHP 5 >= 5.5.0, PHP 7)
imagecropauto — Crop an image automatically using one of the available modes
$image
[, int $mode = IMG_CROP_DEFAULT
[, float $threshold = .5
[, int $color = -1
]]] ) : resource
Automatically crops an image according to the given
mode.
imageРесурс изображения, возвращаемый одной из функций создания изображений, например, такой как imagecreatetruecolor().
modeOne of the following constants:
IMG_CROP_DEFAULTIMG_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_TRANSPARENTIMG_CROP_BLACKIMG_CROP_WHITEIMG_CROP_SIDESIMG_CROP_THRESHOLDthreshold and
color.
thresholdSpecifies 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.
Замечание: Before PHP 7.4.0, the bundled libgd used a somewhat different algorithm, so the same
thresholdyielded different results for system and bundled libgd.
colorEither an RGB color value or a palette index.
Used only in IMG_CROP_THRESHOLD mode.
Returns a cropped image resource on success или FALSE в случае возникновения ошибки.
If the complete image was cropped, imagecrop() returns FALSE.
| Версия | Описание |
|---|---|
| 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.
|
Пример #1 Proper handling of auto-cropping
As noted in the return value section, imagecropauto()
returns FALSE if the whole image
was cropped. In this example we have an image resource
$im which should be automatically cropped only if there
is something to crop; otherwise we want to proceed with the original image.
<?php
$cropped = imagecropauto($im, IMG_CROP_DEFAULT);
if ($cropped !== false) { // in case a new image resource was returned
imagedestroy($im); // we destroy the original image
$im = $cropped; // and assign the cropped image to $im
}
?>