/home/edulekha/studygroup.edulekha.com/ow_libraries/wideimage/vendor/de77/BMP.php
<?php
/**
* @author Gasper Kozak
* @copyright 2007-2011
This file is part of WideImage.
WideImage is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
WideImage is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with WideImage; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
* @package Internal/Mappers
**/
/**
* External code for BMP
*
* Adapted for use in WideImage. Code used with permission from the original author de77.
* http://de77.com/php/read-and-write-bmp-in-php-imagecreatefrombmp-imagebmp
*
* @author de77
* @license MIT
* @url de77.com
* @version 21.08.2010
*
* @package Internal/Mappers
*/
class WideImage_vendor_de77_BMP
{
public static function imagebmp(&$img, $filename = false)
{
$wid = imagesx($img);
$hei = imagesy($img);
$wid_pad = str_pad('', $wid % 4, "\0");
$size = 54 + ($wid + $wid_pad) * $hei * 3; //fixed
//prepare & save header
$header['identifier'] = 'BM';
$header['file_size'] = self::dword($size);
$header['reserved'] = self::dword(0);
$header['bitmap_data'] = self::dword(54);
$header['header_size'] = self::dword(40);
$header['width'] = self::dword($wid);
$header['height'] = self::dword($hei);
$header['planes'] = self::word(1);
$header['bits_per_pixel'] = self::word(24);
$header['compression'] = self::dword(0);
$header['data_size'] = self::dword(0);
$header['h_resolution'] = self::dword(0);
$header['v_resolution'] = self::dword(0);
$header['colors'] = self::dword(0);
$header['important_colors'] = self::dword(0);
if ($filename)
{
$f = fopen($filename, "wb");
foreach ($header AS $h)
{
fwrite($f, $h);
}
//save pixels
for ($y=$hei-1; $y>=0; $y--)
{
for ($x=0; $x<$wid; $x++)
{
$rgb = imagecolorat($img, $x, $y);
fwrite($f, self::byte3($rgb));
}
fwrite($f, $wid_pad);
}
fclose($f);
}
else
{
foreach ($header AS $h)
{
echo $h;
}
//save pixels
for ($y=$hei-1; $y>=0; $y--)
{
for ($x=0; $x<$wid; $x++)
{
$rgb = imagecolorat($img, $x, $y);
echo self::byte3($rgb);
}
echo $wid_pad;
}
}
return true;
}
public static function imagecreatefromstring($data)
{
//read header
$pos = 0;
$header = substr($data, 0, 54);
$pos = 54;
if (strlen($header) < 54)
return false;
$header = unpack( 'c2identifier/Vfile_size/Vreserved/Vbitmap_data/Vheader_size/' .
'Vwidth/Vheight/vplanes/vbits_per_pixel/Vcompression/Vdata_size/'.
'Vh_resolution/Vv_resolution/Vcolors/Vimportant_colors', $header);
if ($header['identifier1'] != 66 or $header['identifier2'] != 77)
{
return false;
//die('Not a valid bmp file');
}
if (!in_array($header['bits_per_pixel'], array(24, 32, 8, 4, 1)))
{
return false;
//die('Only 1, 4, 8, 24 and 32 bit BMP images are supported');
}
$bps = $header['bits_per_pixel']; //bits per pixel
$wid2 = ceil(($bps/8 * $header['width']) / 4) * 4;
$colors = pow(2, $bps);
$wid = $header['width'];
$hei = $header['height'];
$img = imagecreatetruecolor($header['width'], $header['height']);
//read palette
if ($bps < 9)
{
for ($i=0; $i<$colors; $i++)
{
$palette[] = self::undword(substr($data, $pos, 4));
$pos += 4;
}
}
else
{
if ($bps == 32)
{
imagealphablending($img, false);
imagesavealpha($img, true);
}
$palette = array();
}
//read pixels
for ($y=$hei-1; $y>=0; $y--)
{
$row = substr($data, $pos, $wid2);
$pos += $wid2;
$pixels = self::str_split2($row, $bps, $palette);
for ($x=0; $x<$wid; $x++)
{
self::makepixel($img, $x, $y, $pixels[$x], $bps);
}
}
return $img;
}
public static function imagecreatefrombmp($filename)
{
return self::imagecreatefromstring(file_get_contents($filename));
}
private static function str_split2($row, $bps, $palette)
{
switch ($bps)
{
case 32:
case 24: return str_split($row, $bps/8);
case 8: $out = array();
$count = strlen($row);
for ($i=0; $i<$count; $i++)
{
$out[] = $palette[ ord($row[$i]) ];
}
return $out;
case 4: $out = array();
$count = strlen($row);
for ($i=0; $i<$count; $i++)
{
$roww = ord($row[$i]);
$out[] = $palette[ ($roww & 240) >> 4 ];
$out[] = $palette[ ($roww & 15) ];
}
return $out;
case 1: $out = array();
$count = strlen($row);
for ($i=0; $i<$count; $i++)
{
$roww = ord($row[$i]);
$out[] = $palette[ ($roww & 128) >> 7 ];
$out[] = $palette[ ($roww & 64) >> 6 ];
$out[] = $palette[ ($roww & 32) >> 5 ];
$out[] = $palette[ ($roww & 16) >> 4 ];
$out[] = $palette[ ($roww & 8) >> 3 ];
$out[] = $palette[ ($roww & 4) >> 2 ];
$out[] = $palette[ ($roww & 2) >> 1 ];
$out[] = $palette[ ($roww & 1) ];
}
return $out;
}
}
private static function makepixel($img, $x, $y, $str, $bps)
{
switch ($bps)
{
case 32 : $a = ord($str[0]);
$b = ord($str[1]);
$c = ord($str[2]);
$d = 256 - ord($str[3]); //TODO: gives imperfect results
$pixel = $d*256*256*256 + $c*256*256 + $b*256 + $a;
imagesetpixel($img, $x, $y, $pixel);
break;
case 24 : $a = ord($str[0]);
$b = ord($str[1]);
$c = ord($str[2]);
$pixel = $c*256*256 + $b*256 + $a;
imagesetpixel($img, $x, $y, $pixel);
break;
case 8 :
case 4 :
case 1 : imagesetpixel($img, $x, $y, $str);
break;
}
}
private static function byte3($n)
{
return chr($n & 255) . chr(($n >> 8) & 255) . chr(($n >> 16) & 255);
}
private static function undword($n)
{
$r = unpack("V", $n);
return $r[1];
}
private static function dword($n)
{
return pack("V", $n);
}
private static function word($n)
{
return pack("v", $n);
}
}