image - imagecreatefrombmp not working on php -

i trying half size of bmp image php. pho gd doesnt have imagecreatefrombmp have include seperate function. code doesnt seems working. works jpeg. here code should display half image of bmp image test.bmp

<?php   if (!function_exists("imagecreatefrombmp")) {     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 stuff?             $header = substr( $header, 32 );             // width             $width = hexdec( substr( $header, 0, 2 ) );             // remove stuff?             $header = substr( $header, 8 );             // height             $height = hexdec( substr( $header, 0, 2 ) );             unset( $header );         }         $x = 0;         $y = 1;         $image = imagecreatetruecolor( $width, $height );         foreach( $body $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;     } } // file , new size $filename = 'wheat.bmp'; $percent = 0.5;  // content type header('content-type: image/bmp');  // new sizes list($width, $height) = getimagesize($filename); $newwidth = $width * $percent; $newheight = $height * $percent;  // load $thumb = imagecreatetruecolor($newwidth, $newheight); $source = imagecreatefrombmp($filename);  // resize imagecopyresized($thumb, $source, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);  // output imagejpeg($thumb); ?> 

try imagecreatefromwbmp(). right function convert images bmp file.