owncloud / core

		// read file header

		$meta = unpack('vtype/Vfilesize/Vreserved/Voffset', fread($fh, 14));

		// check for bitmap

		if ($meta['type'] != 19778) {

			trigger_error('imagecreatefrombmp: ' . $fileName . ' is not a bitmap!', E_USER_WARNING);

			return false;

		}

		// read image header

		$meta += unpack('Vheadersize/Vwidth/Vheight/vplanes/vbits/Vcompression/Vimagesize/Vxres/Vyres/Vcolors/Vimportant', fread($fh, 40));

		// read additional 16bit header

			// in rare cases filesize is equal to offset so we need to read physical size

			if ($meta['imagesize'] < 1) {

				$meta['imagesize'] = @filesize($fileName) - $meta['offset'];

				if ($meta['imagesize'] < 1) {

					trigger_error('imagecreatefrombmp: Can not obtain filesize of ' . $fileName . '!', E_USER_WARNING);

					return false;

				}

			}

		}

		// calculate colors