PHP GD Functions

This function creates a WBMP file in $file from the $image which is created by imagecreate or imagecreatetruecolor, for example.

PALETTE IMAGE

is the designation term for images with a small number of colors.

For this type of image, a maximum of 256 colors are accepted.

TRUECOLOR IMAGE

is the designation term for images with a great number of colors.

For this type of image, a maximum of 16,777,216 colors are accepted.

This function returns TRUE on success or FALSE on failure.

However, if libgd fails to output the image, this function returns TRUE.

The WBMP (Wireless Application Protocol Bitmap Format)

(shortened to Wireless Bitmap and with file extension .wbmp) is a monochrome graphics file format optimized for mobile computing devices.

WBMP images are monochrome (black & white) so that the image size is kept to a minimum.

A black pixel is denoted by 0 and a white pixel is denoted by 1.

From Wikipedia, the free encyclopedia.

The WBMP (Wireless Application Protocol Bitmap Format)

comes from the "X Window System", (UNIX and Linux), and is used to store small images such as cursors and icons used in the X graphical interface.

Its support has been removed in major browsers on the Windows™ environment.

However such support is maintained in the most common editors, (GIMP, PhotoShop and PaintShop).


<?php

bool imagewbmp imagewbmp( GdImage $image, 
                                 resource|string|null $file = null, 
                                                          ?int $foreground_color = null )

where,

$image = The image identifier 

$file = The path or stream resource 
           ( SEE the below TABLE ) 
          
$foreground_color = The foreground color obtained 
                              from imagecolorallocate

?>

$image

The image identifier.

$file

The path or stream resource.

$file can reference a local file or, (configuration permitting), a remote file using one of the supported stream wrappers:

STREAM WRAPPERS	MEANING
file://	LOCAL File System
http://	URL HTTP
ftp://	URL FTP
php://	I/O streams
zlib://	Data Compression stream
data://	DATA (RFC-2397)
glob://	Find Filenames
phar://	PHP Archive
ssh2://	Secure Shell 2
rar://	RAR
ogg://	Audio
expect://	Interaction of stream processes
ed48

If not set or null, the raw image stream will be output directly.

$foreground_color

The foreground color.

The default foreground color is black.

The $foreground_color is nullabe since PHP 8.0.0.

EXERCISE


<?php

echo 'PHP VERSION: ' . PHP_VERSION . '<br><br>';

$var = getcwd();

define('PBWWP', 'file://' . $var . '/wbmp/');

echo PBWWP . '<br><br>';
// STREAM WRAPPER MODE

$im01 = imagecreatetruecolor (50, 50);
$black = imagecolorallocate($im01, 0, 0, 0);
$white = imagecolorallocate($im01, 255, 255, 255);

$img_file_name = PBWWP . 'WBMP 001 01.wbmp';

$quality01 = 60;

$bool01 = imagewbmp($im01, $img_file_name, $black);

if ($bool01 == TRUE)
{
$mess01 = 'The image was created
                <br>BUT CAN NOT be displayed!';
echo '$bool01 = ';
var_dump($bool01);
echo '<br><br>' . $mess01;
imagedestroy($im01);
}
else
{
$mess01 = 'The image COULD NOT BE CREATED!';
echo $mess01;
}

?>

RESULT

WBMP 001 01.wbmp

$bool01 = bool(true)

The image was created
BUT CAN NOT be displayed!

EXERCISE


<?php

// Try this code

echo 'PHP VERSION: ' . PHP_VERSION . '<br><br>';

$im02 = imagecreate (50, 50);
$blue = imagecolorallocate($im02, 0, 0, 255);
$green = imagecolorallocate($im02, 0, 255, 0);
$white = imagecolorallocate($im02, 255, 255, 255);

$img_file_name = NULL;

$quality02 = 60;

$bool02 = imagewbmp($im02, $img_file_name, $blue);

if ($bool02 == TRUE)
{
$mess02 = 'The image was created
           <br>BUT CAN NOT be displayed!<br>';
echo '<br><br>$bool02 = ';
var_dump($bool02);
echo '<br><br>' . $mess02;
imagedestroy($im02);
}
else
{
$mess02 = 'The image COULD NOT BE CREATED!';
echo $mess02;
}

?>