imagecropauto

(PHP 5 >= 5.5.0, PHP 7)

imagecropauto — Crop an image automatically using one of the available modes

설명

resource imagecropauto ( resource $image [, int $mode = -1 [, float $threshold = .5 [, int $color = -1 ]]] )

Automatically crops an image according to the given mode.

인수

image

imagecreatetruecolor() 등의 이미지 생성 함수에서 반환한 이미지 자원.

mode

One of the following constants:

IMG_CROP_DEFAULT: Attempts to use IMG_CROP_TRANSPARENT and if it fails it falls back to IMG_CROP_SIDES.
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.

color

Either an RGB color value or a palette index.

Used only in IMG_CROP_THRESHOLD mode.

반환값

Returns a cropped image resource on success실패 시 FALSE를 반환합니다. If no cropping would occur, or the complete image would be cropped, that is treated as failure, i.e. imagecrop() returns FALSE.

예제

Example #1 Proper handling of auto-cropping

As noted in the return value section, imagecropauto() returns FALSE when there is either nothing to crop or the whole image would be 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
}
?>

참고

imagecrop() - Crop an image to the given rectangle

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User Contributed Notes 2 notes

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raphael.deiana ¶

7 years ago


In some cases the use of the IMG_CROP_WHITE or IMG_CROP_BLACK does not work. The function returns FALSE. It is best to use the IMG_CROP_THRESHOLD mode and specify the color in fourth argument as in the example below :

<?php

$original_img = imagecreatefromjpeg($image_path);

// Use this :
$cropped_img_white = imagecropauto($original_img , IMG_CROP_THRESHOLD, null, 16777215);
// Rather than :
$cropped_img_white = imagecropauto($original_img , IMG_CROP_WHITE);

// AND

// Use this :
$cropped_img_black = imagecropauto($original_img , IMG_CROP_THRESHOLD, null, 0);
// Rather than :
$cropped_img_black = imagecropauto($original_img , IMG_CROP_BLACK);

?>

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Ray.Paseur sometimes uses Gmail ¶

7 years ago


Please see the note on ImageCrop() that describes an extraneous black line at the bottom of the cropped image.
http://php.net/manual/en/function.imagecrop.php#119537

Bug 67447 applies to ImageCropAuto(), too.
https://bugs.php.net/bug.php?id=67447

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