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Updated to work with <24 bit BMP

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Subject:Updated to work with <24 bit BMP
Summary:Updated code
Messages:1
Author:Roger
Date:2011-07-24 14:00:17
 

  1. Updated to work with <24 bit BMP   Reply   Report abuse  
Picture of Roger Roger - 2011-07-24 14:00:18
Hi,

I updated the function 'ImageCreateFromBMP'

Found here: http://php.net/manual/en/function.imagecreate.php

and renamed to 'imagecreatefrombmp' and now it works with all BMPs not just 24 bit ;-)

/*********************************************/
/* Fonction: ImageCreateFromBMP */
/* Author: DHKold */
/* Contact: admin@dhkold.com */
/* Date: The 15th of June 2005 */
/* Version: 2.0B */
/*********************************************/
function imagecreatefrombmp($filename)
{
//Ouverture du fichier en mode binaire
if (! $f1 = fopen($filename,"rb")) return FALSE;

//1 : Chargement des ent&#65533;tes FICHIER
$FILE = unpack("vfile_type/Vfile_size/Vreserved/Vbitmap_offset", fread($f1,14));
if ($FILE['file_type'] != 19778) return FALSE;

//2 : Chargement des ent&#65533;tes BMP
$BMP = unpack('Vheader_size/Vwidth/Vheight/vplanes/vbits_per_pixel'.
'/Vcompression/Vsize_bitmap/Vhoriz_resolution'.
'/Vvert_resolution/Vcolors_used/Vcolors_important', fread($f1,40));
$BMP['colors'] = pow(2,$BMP['bits_per_pixel']);
if ($BMP['size_bitmap'] == 0) $BMP['size_bitmap'] = $FILE['file_size'] - $FILE['bitmap_offset'];
$BMP['bytes_per_pixel'] = $BMP['bits_per_pixel']/8;
$BMP['bytes_per_pixel2'] = ceil($BMP['bytes_per_pixel']);
$BMP['decal'] = ($BMP['width']*$BMP['bytes_per_pixel']/4);
$BMP['decal'] -= floor($BMP['width']*$BMP['bytes_per_pixel']/4);
$BMP['decal'] = 4-(4*$BMP['decal']);
if ($BMP['decal'] == 4) $BMP['decal'] = 0;

//3 : Chargement des couleurs de la palette
$PALETTE = array();
if ($BMP['colors'] < 16777216)
{
$PALETTE = unpack('V'.$BMP['colors'], fread($f1,$BMP['colors']*4));
}

//4 : Cr&#65533;ation de l'image
$IMG = fread($f1,$BMP['size_bitmap']);
$VIDE = chr(0);

$res = imagecreatetruecolor($BMP['width'],$BMP['height']);
$P = 0;
$Y = $BMP['height']-1;
while ($Y >= 0)
{
$X=0;
while ($X < $BMP['width'])
{
if ($BMP['bits_per_pixel'] == 24)
$COLOR = unpack("V",substr($IMG,$P,3).$VIDE);
elseif ($BMP['bits_per_pixel'] == 16)
{
$COLOR = unpack("n",substr($IMG,$P,2));
$COLOR[1] = $PALETTE[$COLOR[1]+1];
}
elseif ($BMP['bits_per_pixel'] == 8)
{
$COLOR = unpack("n",$VIDE.substr($IMG,$P,1));
$COLOR[1] = $PALETTE[$COLOR[1]+1];
}
elseif ($BMP['bits_per_pixel'] == 4)
{
$COLOR = unpack("n",$VIDE.substr($IMG,floor($P),1));
if (($P*2)%2 == 0) $COLOR[1] = ($COLOR[1] >> 4) ; else $COLOR[1] = ($COLOR[1] & 0x0F);
$COLOR[1] = $PALETTE[$COLOR[1]+1];
}
elseif ($BMP['bits_per_pixel'] == 1)
{
$COLOR = unpack("n",$VIDE.substr($IMG,floor($P),1));
if (($P*8)%8 == 0) $COLOR[1] = $COLOR[1] >>7;
elseif (($P*8)%8 == 1) $COLOR[1] = ($COLOR[1] & 0x40)>>6;
elseif (($P*8)%8 == 2) $COLOR[1] = ($COLOR[1] & 0x20)>>5;
elseif (($P*8)%8 == 3) $COLOR[1] = ($COLOR[1] & 0x10)>>4;
elseif (($P*8)%8 == 4) $COLOR[1] = ($COLOR[1] & 0x8)>>3;
elseif (($P*8)%8 == 5) $COLOR[1] = ($COLOR[1] & 0x4)>>2;
elseif (($P*8)%8 == 6) $COLOR[1] = ($COLOR[1] & 0x2)>>1;
elseif (($P*8)%8 == 7) $COLOR[1] = ($COLOR[1] & 0x1);
$COLOR[1] = $PALETTE[$COLOR[1]+1];
}
else
return FALSE;
imagesetpixel($res,$X,$Y,$COLOR[1]);
$X++;
$P += $BMP['bytes_per_pixel'];
}
$Y--;
$P+=$BMP['decal'];
}

//Fermeture du fichier
fclose($f1);

return $res;
}