PHP Velho Oeste 2024

imagecreatefromwbmp

(PHP 4 >= 4.0.1, PHP 5, PHP 7, PHP 8)

imagecreatefromwbmpCreate a new image from file or URL

Description

imagecreatefromwbmp(string $filename): GdImage|false

imagecreatefromwbmp() returns an image identifier representing the image obtained from the given filename.

Note: WBMP images are Wireless Bitmaps, not Windows Bitmaps. The latter can be loaded with imagecreatefrombmp().

Tip

A URL can be used as a filename with this function if the fopen wrappers have been enabled. See fopen() for more details on how to specify the filename. See the Supported Protocols and Wrappers for links to information about what abilities the various wrappers have, notes on their usage, and information on any predefined variables they may provide.

Parameters

filename

Path to the WBMP image.

Return Values

Returns an image object on success, false on errors.

Changelog

Version Description
8.0.0 On success, this function returns a GDImage instance now; previously, a resource was returned.

Examples

Example #1 Example to handle an error during loading of a WBMP

<?php
function LoadWBMP($imgname)
{
/* Attempt to open */
$im = @imagecreatefromwbmp($imgname);

/* See if it failed */
if(!$im)
{
/* Create a blank image */
$im = imagecreatetruecolor(150, 30);
$bgc = imagecolorallocate($im, 255, 255, 255);
$tc = imagecolorallocate($im, 0, 0, 0);

imagefilledrectangle($im, 0, 0, 150, 30, $bgc);

/* Output an error message */
imagestring($im, 1, 5, 5, 'Error loading ' . $imgname, $tc);
}

return
$im;
}

header('Content-Type: image/vnd.wap.wbmp');

$img = LoadWBMP('bogus.image');

imagewbmp($img);
imagedestroy($img);
?>
add a note add a note

User Contributed Notes 4 notes

up
12
clambert at whitecrown dot net
22 years ago
WBMP images are Wireless Bitmaps, not Windows Bitmaps. WBMP is used for bandwidth constrained, black and white, limited devices such as PDAs and Cell Phones.
up
8
AeroX @ aerox-studios
15 years ago
.bmp is just hex encoded RGB values.
All you need to do is open in binary mode and seperate the header from the body.
Decode the width and height from the header.
Then create the image pixel by pixel from the RGB values in the body.

function imagecreatefrombmp( $filename )
{
    $file = fopen( $filename, "rb" );
    $read = fread( $file, 10 );
    while( !feof( $file ) && $read != "" )
    {
        $read .= fread( $file, 1024 );
    }
    $temp = unpack( "H*", $read );
    $hex = $temp[1];
    $header = substr( $hex, 0, 104 );
    $body = str_split( substr( $hex, 108 ), 6 );
    if( substr( $header, 0, 4 ) == "424d" )
    {
        $header = substr( $header, 4 );
        // Remove some stuff?
        $header = substr( $header, 32 );
        // Get the width
        $width = hexdec( substr( $header, 0, 2 ) );
        // Remove some stuff?
        $header = substr( $header, 8 );
        // Get the height
        $height = hexdec( substr( $header, 0, 2 ) );
        unset( $header );
    }
    $x = 0;
    $y = 1;
    $image = imagecreatetruecolor( $width, $height );
    foreach( $body as $rgb )
    {
        $r = hexdec( substr( $rgb, 4, 2 ) );
        $g = hexdec( substr( $rgb, 2, 2 ) );
        $b = hexdec( substr( $rgb, 0, 2 ) );
        $color = imagecolorallocate( $image, $r, $g, $b );
        imagesetpixel( $image, $x, $height-$y, $color );
        $x++;
        if( $x >= $width )
        {
            $x = 0;
            $y++;
        }
    }
    return $image;
}
up
7
alexander at alexauto dot nl
15 years ago
AeroX created a nice example, but it only works at specific imagesizes because bmp uses fully 32-bit lines. To prevent failures (different colors, pixel-shifting per line), the solution is to skip the padding, inserted after color-pixels on the line. His implementation did cutting the padding into the image-data, causing wrong colors, pixel-shifting per line and also an large memory-consumption.

I improved this script to the next implementation. The readability of a image is checked by a other function, so it doesn't take part in this script.
Suggestions? Please let me know.

<?php
   
public function imagecreatefrombmp($p_sFile)
    {
       
//    Load the image into a string
       
$file    =    fopen($p_sFile,"rb");
       
$read    =    fread($file,10);
        while(!
feof($file)&&($read<>""))
           
$read    .=    fread($file,1024);
       
       
$temp    =    unpack("H*",$read);
       
$hex    =    $temp[1];
       
$header    =    substr($hex,0,108);
       
       
//    Process the header
        //    Structure: http://www.fastgraph.com/help/bmp_header_format.html
       
if (substr($header,0,4)=="424d")
        {
           
//    Cut it in parts of 2 bytes
           
$header_parts    =    str_split($header,2);
           
           
//    Get the width        4 bytes
           
$width            =    hexdec($header_parts[19].$header_parts[18]);
           
           
//    Get the height        4 bytes
           
$height            =    hexdec($header_parts[23].$header_parts[22]);
           
           
//    Unset the header params
           
unset($header_parts);
        }
       
       
//    Define starting X and Y
       
$x                =    0;
       
$y                =    1;
       
       
//    Create newimage
       
$image            =    imagecreatetruecolor($width,$height);
       
       
//    Grab the body from the image
       
$body            =    substr($hex,108);

       
//    Calculate if padding at the end-line is needed
        //    Divided by two to keep overview.
        //    1 byte = 2 HEX-chars
       
$body_size        =    (strlen($body)/2);
       
$header_size    =    ($width*$height);

       
//    Use end-line padding? Only when needed
       
$usePadding        =    ($body_size>($header_size*3)+4);
       
       
//    Using a for-loop with index-calculation instaid of str_split to avoid large memory consumption
        //    Calculate the next DWORD-position in the body
       
for ($i=0;$i<$body_size;$i+=3)
        {
           
//    Calculate line-ending and padding
           
if ($x>=$width)
            {
               
//    If padding needed, ignore image-padding
                //    Shift i to the ending of the current 32-bit-block
               
if ($usePadding)
                   
$i    +=    $width%4;
               
               
//    Reset horizontal position
               
$x    =    0;
               
               
//    Raise the height-position (bottom-up)
               
$y++;
               
               
//    Reached the image-height? Break the for-loop
               
if ($y>$height)
                    break;
            }
           
           
//    Calculation of the RGB-pixel (defined as BGR in image-data)
            //    Define $i_pos as absolute position in the body
           
$i_pos    =    $i*2;
           
$r        =    hexdec($body[$i_pos+4].$body[$i_pos+5]);
           
$g        =    hexdec($body[$i_pos+2].$body[$i_pos+3]);
           
$b        =    hexdec($body[$i_pos].$body[$i_pos+1]);
           
           
//    Calculate and draw the pixel
           
$color    =    imagecolorallocate($image,$r,$g,$b);
           
imagesetpixel($image,$x,$height-$y,$color);
           
           
//    Raise the horizontal position
           
$x++;
        }
       
       
//    Unset the body / free the memory
       
unset($body);
       
       
//    Return image-object
       
return $image;
    }
?>
up
-1
php at webdecker dot de
14 years ago
To get the horizontal and vertical resolution you could add some lines to the previous code of alexander. BMP stores the resolution in pixels per meter. To get it as pixels per inch (dpi) you have to multiply the value by 0.0254.

<?php
   
public function imagecreatefrombmp($p_sFile)
    {
           
// ...
            // ... insert after the lines where you get width and height...

            //    Get the horz. resolution in pixel per meter, 4 bytes
           
$dpix = hexdec($header_parts[39]. $header_parts[38]) * 0.0254;
           
           
//    Get the vert. resolution in pixel per meter, 4 bytes
           
$dpiy = hexdec($header_parts[43]. $header_parts[42]) * 0.0254;

           
// ... rest of the code...

           
return ($image, $dpix, $dpiy);
    }          
?>
To Top