Someone posted a function to implement imagecreatefrom bmp()but it
fails in imagecreatedfro mgd() in my test. Can the author check to see
if theres a typo? Its very useful if it will work!
Brian
"Erwin Bon" <ernie@verkerk. nl> wrote in message news:<3fc9d260$ 0$4671$1b62eedf @news.euronet.n l>...[color=blue]
> Hello,
>
> I need to be able to read windows bitmap files (*.bmp) into the GD-functions
> in order to create a jpg-file from it. Is such a thing possible. I seem te
> be unable to find the required functions.
>
> Hope you can help me.
>
> Regards, Erwin[/color]
The GD library doesn't support .BMP files for some reason. I've
written a function that converts .BMP files to .GD, a very simple
format that GD uses.
The following code implements imagecreatefrom bmp(). It first convert
the BMP to GD, saving it to a temporary location, then open the image
using imagecreatefrom gd().
<?
function ConvertBMP2GD($ src, $dest = false) {
if(!($src_f = fopen($src, "rb"))) {
return false;
}
if(!($dest_f = fopen($dest, "wb"))) {
return false;
}
$header = unpack("vtype/Vsize/v2reserved/Voffset", fread($src_f,
14));
$info = unpack("Vsize/Vwidth/Vheight/vplanes/vbits/Vcompression/Vimagesize/Vxres/Vyres/Vncolor/Vimportant",
fread($src_f, 40));
extract($info);
extract($header );
if($type != 0x4D42) { // signature "BM"
return false;
}
$palette_size = $offset - 54;
$ncolor = $palette_size / 4;
$gd_header = "";
// true-color vs. palette
$gd_header .= ($palette_size == 0) ? "\xFF\xFE" : "\xFF\xFF";
$gd_header .= pack("n2", $width, $height);
$gd_header .= ($palette_size == 0) ? "\x01" : "\x00";
if($palette_siz e) {
$gd_header .= pack("n", $ncolor);
}
// no transparency
$gd_header .= "\xFF\xFF\xFF\x FF";
fwrite($dest_f, $gd_header);
if($palette_siz e) {
$palette = fread($src_f, $palette_size);
$gd_palette = "";
$j = 0;
while($j < $palette_size) {
$b = $palette{$j++};
$g = $palette{$j++};
$r = $palette{$j++};
$a = $palette{$j++};
$gd_palette .= "$r$g$b$a";
}
$gd_palette .= str_repeat("\x0 0\x00\x00\x00", 256 - $ncolor);
fwrite($dest_f, $gd_palette);
}
$scan_line_size = (($bits * $width) + 7) >> 3;
$scan_line_alig n = ($scan_line_siz e & 0x03) ? 4 - ($scan_line_siz e &
0x03) : 0;
for($i = 0, $l = $height - 1; $i < $height; $i++, $l--) {
// BMP stores scan lines starting from bottom
fseek($src_f, $offset + (($scan_line_si ze + $scan_line_alig n) *
$l));
$scan_line = fread($src_f, $scan_line_size );
if($bits == 24) {
$gd_scan_line = "";
$j = 0;
while($j < $scan_line_size ) {
$b = $scan_line{$j++ };
$g = $scan_line{$j++ };
$r = $scan_line{$j++ };
$gd_scan_line .= "\x00$r$g$b ";
}
}
else if($bits == 8) {
$gd_scan_line = $scan_line;
}
else if($bits == 4) {
$gd_scan_line = "";
$j = 0;
while($j < $scan_line_size ) {
$byte = ord($scan_line{ $j++});
$p1 = chr($byte >> 4);
$p2 = chr($byte & 0x0F);
$gd_scan_line .= "$p1$p2";
} $gd_scan_line = substr($gd_scan _line, 0, $width);
}
else if($bits == 1) {
$gd_scan_line = "";
$j = 0;
while($j < $scan_line_size ) {
$byte = ord($scan_line{ $j++});
$p1 = chr((int) (($byte & 0x80) != 0));
$p2 = chr((int) (($byte & 0x40) != 0));
$p3 = chr((int) (($byte & 0x20) != 0));
$p4 = chr((int) (($byte & 0x10) != 0));
$p5 = chr((int) (($byte & 0x08) != 0));
$p6 = chr((int) (($byte & 0x04) != 0));
$p7 = chr((int) (($byte & 0x02) != 0));
$p8 = chr((int) (($byte & 0x01) != 0));
$gd_scan_line .= "$p1$p2$p3$p4$p 5$p6$p7$p8";
} $gd_scan_line = substr($gd_scan _line, 0, $width);
}
fwrite($dest_f, $gd_scan_line);
}
fclose($src_f);
fclose($dest_f) ;
return true;
}
function imagecreatefrom bmp($filename) {
$tmp_name = tempnam("/tmp", "GD");
if(ConvertBMP2G D($filename, $tmp_name)) {
$img = imagecreatefrom gd($tmp_name);
unlink($tmp_nam e);
return $img;
} return false;
}
$img = imagecreatefrom bmp("test24bit. bmp");
imagejpeg($img, "test.jpg") ;
?>
<img src="test.jpg">
fails in imagecreatedfro mgd() in my test. Can the author check to see
if theres a typo? Its very useful if it will work!
Brian
"Erwin Bon" <ernie@verkerk. nl> wrote in message news:<3fc9d260$ 0$4671$1b62eedf @news.euronet.n l>...[color=blue]
> Hello,
>
> I need to be able to read windows bitmap files (*.bmp) into the GD-functions
> in order to create a jpg-file from it. Is such a thing possible. I seem te
> be unable to find the required functions.
>
> Hope you can help me.
>
> Regards, Erwin[/color]
The GD library doesn't support .BMP files for some reason. I've
written a function that converts .BMP files to .GD, a very simple
format that GD uses.
The following code implements imagecreatefrom bmp(). It first convert
the BMP to GD, saving it to a temporary location, then open the image
using imagecreatefrom gd().
<?
function ConvertBMP2GD($ src, $dest = false) {
if(!($src_f = fopen($src, "rb"))) {
return false;
}
if(!($dest_f = fopen($dest, "wb"))) {
return false;
}
$header = unpack("vtype/Vsize/v2reserved/Voffset", fread($src_f,
14));
$info = unpack("Vsize/Vwidth/Vheight/vplanes/vbits/Vcompression/Vimagesize/Vxres/Vyres/Vncolor/Vimportant",
fread($src_f, 40));
extract($info);
extract($header );
if($type != 0x4D42) { // signature "BM"
return false;
}
$palette_size = $offset - 54;
$ncolor = $palette_size / 4;
$gd_header = "";
// true-color vs. palette
$gd_header .= ($palette_size == 0) ? "\xFF\xFE" : "\xFF\xFF";
$gd_header .= pack("n2", $width, $height);
$gd_header .= ($palette_size == 0) ? "\x01" : "\x00";
if($palette_siz e) {
$gd_header .= pack("n", $ncolor);
}
// no transparency
$gd_header .= "\xFF\xFF\xFF\x FF";
fwrite($dest_f, $gd_header);
if($palette_siz e) {
$palette = fread($src_f, $palette_size);
$gd_palette = "";
$j = 0;
while($j < $palette_size) {
$b = $palette{$j++};
$g = $palette{$j++};
$r = $palette{$j++};
$a = $palette{$j++};
$gd_palette .= "$r$g$b$a";
}
$gd_palette .= str_repeat("\x0 0\x00\x00\x00", 256 - $ncolor);
fwrite($dest_f, $gd_palette);
}
$scan_line_size = (($bits * $width) + 7) >> 3;
$scan_line_alig n = ($scan_line_siz e & 0x03) ? 4 - ($scan_line_siz e &
0x03) : 0;
for($i = 0, $l = $height - 1; $i < $height; $i++, $l--) {
// BMP stores scan lines starting from bottom
fseek($src_f, $offset + (($scan_line_si ze + $scan_line_alig n) *
$l));
$scan_line = fread($src_f, $scan_line_size );
if($bits == 24) {
$gd_scan_line = "";
$j = 0;
while($j < $scan_line_size ) {
$b = $scan_line{$j++ };
$g = $scan_line{$j++ };
$r = $scan_line{$j++ };
$gd_scan_line .= "\x00$r$g$b ";
}
}
else if($bits == 8) {
$gd_scan_line = $scan_line;
}
else if($bits == 4) {
$gd_scan_line = "";
$j = 0;
while($j < $scan_line_size ) {
$byte = ord($scan_line{ $j++});
$p1 = chr($byte >> 4);
$p2 = chr($byte & 0x0F);
$gd_scan_line .= "$p1$p2";
} $gd_scan_line = substr($gd_scan _line, 0, $width);
}
else if($bits == 1) {
$gd_scan_line = "";
$j = 0;
while($j < $scan_line_size ) {
$byte = ord($scan_line{ $j++});
$p1 = chr((int) (($byte & 0x80) != 0));
$p2 = chr((int) (($byte & 0x40) != 0));
$p3 = chr((int) (($byte & 0x20) != 0));
$p4 = chr((int) (($byte & 0x10) != 0));
$p5 = chr((int) (($byte & 0x08) != 0));
$p6 = chr((int) (($byte & 0x04) != 0));
$p7 = chr((int) (($byte & 0x02) != 0));
$p8 = chr((int) (($byte & 0x01) != 0));
$gd_scan_line .= "$p1$p2$p3$p4$p 5$p6$p7$p8";
} $gd_scan_line = substr($gd_scan _line, 0, $width);
}
fwrite($dest_f, $gd_scan_line);
}
fclose($src_f);
fclose($dest_f) ;
return true;
}
function imagecreatefrom bmp($filename) {
$tmp_name = tempnam("/tmp", "GD");
if(ConvertBMP2G D($filename, $tmp_name)) {
$img = imagecreatefrom gd($tmp_name);
unlink($tmp_nam e);
return $img;
} return false;
}
$img = imagecreatefrom bmp("test24bit. bmp");
imagejpeg($img, "test.jpg") ;
?>
<img src="test.jpg">
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