If you're using PHP < 5.5 you can use this code to add the same functionality. If you pass the wrong $mode in it will silently fail. You might want to add your own error handling for this case.
<?php
if (!function_exists('imageflip')) {
define('IMG_FLIP_HORIZONTAL', 0);
define('IMG_FLIP_VERTICAL', 1);
define('IMG_FLIP_BOTH', 2);
function imageflip($image, $mode) {
switch ($mode) {
case IMG_FLIP_HORIZONTAL: {
$max_x = imagesx($image) - 1;
$half_x = $max_x / 2;
$sy = imagesy($image);
$temp_image = imageistruecolor($image)? imagecreatetruecolor(1, $sy): imagecreate(1, $sy);
for ($x = 0; $x < $half_x; ++$x) {
imagecopy($temp_image, $image, 0, 0, $x, 0, 1, $sy);
imagecopy($image, $image, $x, 0, $max_x - $x, 0, 1, $sy);
imagecopy($image, $temp_image, $max_x - $x, 0, 0, 0, 1, $sy);
}
break;
}
case IMG_FLIP_VERTICAL: {
$sx = imagesx($image);
$max_y = imagesy($image) - 1;
$half_y = $max_y / 2;
$temp_image = imageistruecolor($image)? imagecreatetruecolor($sx, 1): imagecreate($sx, 1);
for ($y = 0; $y < $half_y; ++$y) {
imagecopy($temp_image, $image, 0, 0, 0, $y, $sx, 1);
imagecopy($image, $image, 0, $y, 0, $max_y - $y, $sx, 1);
imagecopy($image, $temp_image, 0, $max_y - $y, 0, 0, $sx, 1);
}
break;
}
case IMG_FLIP_BOTH: {
$sx = imagesx($image);
$sy = imagesy($image);
$temp_image = imagerotate($image, 180, 0);
imagecopy($image, $temp_image, 0, 0, 0, 0, $sx, $sy);
break;
}
default: {
return;
}
}
imagedestroy($temp_image);
}
}
?>
imageflip
(PHP 5 >= 5.5.0, PHP 7, PHP 8)
imageflip — Flips an image using a given mode
参数
-
image -
由图象创建函数(例如imagecreatetruecolor())返回的图象资源。
-
mode -
Flip mode, this can be one of the
IMG_FLIP_*constants:Constant Meaning IMG_FLIP_HORIZONTALFlips the image horizontally. IMG_FLIP_VERTICALFlips the image vertically. IMG_FLIP_BOTHFlips the image both horizontally and vertically.
返回值
成功时返回 true， 或者在失败时返回 false。
更新日志
| 版本 | 说明 |
|---|---|
| 8.0.0 |
image expects a GdImage
instance now; previously, a resource was expected.
|
范例
Example #1 Flips an image vertically
This example uses the IMG_FLIP_VERTICAL
constant.
<?php
// File
$filename = 'phplogo.png';
// Content type
header('Content-type: image/png');
// Load
$im = imagecreatefrompng($filename);
// Flip it vertically
imageflip($im, IMG_FLIP_VERTICAL);
// Output
imagejpeg($im);
imagedestroy($im);
?>
以上例程的输出类似于：
Example #2 Flips the image horizontally
This example uses the IMG_FLIP_HORIZONTAL constant.
<?php
// File
$filename = 'phplogo.png';
// Content type
header('Content-type: image/png');
// Load
$im = imagecreatefrompng($filename);
// Flip it horizontally
imageflip($im, IMG_FLIP_HORIZONTAL);
// Output
imagejpeg($im);
imagedestroy($im);
?>
以上例程的输出类似于：
User Contributed Notes
Daniel Klein
04-Feb-2016 01:26