note 86214 added to function.imagecreatefromwbmp

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.

	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;
	}
----
Server IP: 89.248.170.61
Probable Submitter: 87.208.85.212
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Manual Page -- http://www.php.net/manual/en/function.imagecreatefromwbmp.php
Edit        -- https://master.php.net/note/edit/86214
Del: integrated  -- https://master.php.net/note/delete/86214/integrated
Del: useless     -- https://master.php.net/note/delete/86214/useless
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Del: non-english -- https://master.php.net/note/delete/86214/non-english
Del: in docs     -- https://master.php.net/note/delete/86214/in+docs
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