PHP 7.0.6 Released

imageflip

(PHP 5 >= 5.5.0, PHP 7)

imageflipFlips an image using a given mode

Description

bool imageflip ( resource $image , int $mode )

Flips the image image using the given mode.

Parameters

image

An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().

mode

Flip mode, this can be one of the IMG_FLIP_* constants:

Constant Meaning
IMG_FLIP_HORIZONTAL Flips the image horizontally.
IMG_FLIP_VERTICAL Flips the image vertically.
IMG_FLIP_BOTH Flips the image both horizontally and vertically.

Return Values

Returns TRUE on success or FALSE on failure.

Examples

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($imIMG_FLIP_VERTICAL);

// Output
imagejpeg($im);
imagedestroy($im);
?>

The above example will output something similar to:

Output of example: Vertically flipped image

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($imIMG_FLIP_HORIZONTAL);

// Output
imagejpeg($im);
imagedestroy($im);
?>

The above example will output something similar to:

Output of example: Horizontally flipped image

Notes

Note: This function is only available if PHP is compiled with the bundled version of the GD library.

User Contributed Notes

Daniel Klein
2 months ago
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);
  }
}
?>
To Top