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.
imagecreatefromwbmp
(PHP 4 >= 4.0.1, PHP 5, PHP 7, PHP 8)
imagecreatefromwbmp — 新しい画像をファイルあるいは URL から作成する
説明
imagecreatefromwbmp() は、指定したファイル名から 得られたイメージを表すイメージ ID を返します。
注意: WBMP画像は、Windows bitmp ではなく、ワイヤレスビットマップです。 Windows bitmap は、imagecreatefrombmp() 関数を使って読み込むことができます。
ヒント
fopen wrappers が有効の場合、この関数のファイル名として URL を使用することができます。ファイル名の指定方法に関する詳細は fopen() を参照ください。 サポートするプロトコル/ラッパー には、さまざまなラッパーの機能やその使用法、 提供される定義済み変数などの情報がまとめられています。
パラメータ
-
filename -
WBMP 画像へのパス。
戻り値
成功した場合に画像オブジェクト、エラー時に false を返します。
例
例1 WBMP の作成時のエラーを処理する例
<?php
function LoadWBMP($imgname)
{
/* オープンします */
$im = @imagecreatefromwbmp($imgname);
/* 失敗したかどうかを調べます */
if(!$im)
{
/* 空の画像を作成します */
$im = imagecreatetruecolor(150, 30);
$bgc = imagecolorallocate($im, 255, 255, 255);
$tc = imagecolorallocate($im, 0, 0, 0);
imagefilledrectangle($im, 0, 0, 150, 30, $bgc);
/* エラーメッセージを出力します */
imagestring($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
User Contributed Notes 4 notes
clambert at whitecrown dot net ¶
23 years ago
AeroX @ aerox-studios ¶
16 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 $image;
}
alexander at alexauto dot nl ¶
16 years ago
AeroX created a nice example, but it only works at specific imagesizes because bmp uses fully 32-bit lines. To prevent failures (different colors, pixel-shifting per line), the solution is to skip the padding, inserted after color-pixels on the line. His implementation did cutting the padding into the image-data, causing wrong colors, pixel-shifting per line and also an large memory-consumption.
I improved this script to the next implementation. The readability of a image is checked by a other function, so it doesn't take part in this script.
Suggestions? Please let me know.
<?php
public function imagecreatefrombmp($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 $image;
}
?>
php at webdecker dot de ¶
14 years ago
To get the horizontal and vertical resolution you could add some lines to the previous code of alexander. BMP stores the resolution in pixels per meter. To get it as pixels per inch (dpi) you have to multiply the value by 0.0254.
<?php
public function imagecreatefrombmp($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);
}
?>
