imagecreate

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help at nanomc dot com
09-Nov-2005 03:29


// A simple XY graph 





<html>


<head>


        


 <title>XY Graph</title>





<h2>Practice XY Graph</h2>


</head>


<body>





<?php 


$left = 0;


$top = 0;


$x_size = 400;


$y_size = 400;





$char_width = 8;


$char_height = 11;





$x_start = $x_left + 100;


$y_start = $top + $char_height * 1.5;


$x_end = $x_start + $x_size;


$y_end = $y_start + $y_size;


$right = $x_start + $x_size + 40;


$bottom = $y_start + $y_size + $char_height * 1.5;





$graph_n = 100;


for($i = 0; $i < $graph_n; $i++ )


    {


    $graph_x[$i] = $i;


    $graph_y[$i] = $i * $i;


    }





    $min_x = 9e99;


    $min_y = 9e99;


    $max_x = -9e99;


    $max_y = -9e99;





    $avg_y = 0.0;


    


    for($i = 0; $i < $graph_n; $i++ )


        {


        if( $graph_x[$i] < $min_x )


            $min_x = $graph_x[$i];





        if( $graph_x[$i] > $max_x )


            $max_x = $graph_x[$i];





        if( $graph_y[$i] < $min_y )


            $min_y = $graph_y[$i];





        if( $graph_y[$i] > $max_y )


            $max_y = $graph_y[$i];





        $avg_y += $graph_y[$i];


        }


    


    $avg_y = $avg_y / $graph_n;





    $min_x = 0;


    $min_y = 0;


    $max_x += $max_x * 0.05;


    $max_y += $max_y * 0.05;





$image = ImageCreate($right - $left, $bottom - $top);


$background_color = imagecolorallocate($image, 255, 255, 255);


$text_color = imagecolorallocate($image, 233, 14, 91);





$grey = ImageColorAllocate($image, 204, 204, 204); 


$white = imagecolorallocate($image, 255, 255, 255);


$black = imagecolorallocate($image, 0, 0, 0);


$red = imagecolorallocate($image, 255, 0, 0);





imagerectangle($image, $left, $top, $right - 1, $bottom - 1, $black );


imagerectangle($image, $x_start, $y_start, $x_end, $y_end, $grey );





for($i = 0; $i < $graph_n; $i++ )


   {


   $pt_x = $x_start + ($x_end-$x_start)*($graph_x[$i]-$min_x)/($max_x-$min_x);


   $pt_y = $y_end - ($y_end - $y_start)*($graph_y[$i]-$min_y)/($max_y-$min_y);





 //  imagesetpixel( $image, $pt_x, $pt_y, $black );


   imagechar($image, 2, $pt_x - 3, $pt_y - 10, '.', $black);


   }





$string = sprintf("%2.5f", $max_y);


imagestring($image, 4, $x_start - strlen($string) * $char_width, $y_start - $char_width, $string, $black);





$string = sprintf("%2.5f", $min_y);


imagestring($image, 4, $x_start - strlen($string) * $char_width, $y_end - $char_height, $string, $black);





$string = sprintf("%2.5f", $min_x);


imagestring($image, 4, $x_start - (strlen($string) * $char_width)/2, $y_end, $string, $black);


    


$string = sprintf("%2.5f", $max_x);


imagestring($image, 4, $x_end - (strlen($string) * $char_width) / 2, $y_end, $string, $black);





$x_title = 'x axis';


$y_title = 'y axis';





imagestring($image, 4, $x_start + ($x_end - $x_start) / 2 - strlen($x_title) * $char_width / 2, $y_end, $x_title, $black);





imagestring($image, 4, $char_width, ($y_end - $y_start) / 2, $y_title, $black);





header('Content-type: image/png');


$filename = sprintf("%d.png", time());


ImagePNG($image,$filename);


ImageDestroy($image);





printf("<img src='%s'> ", $filename);


?> 





</body>


</html>

DHKold
16-Jun-2005 05:52


to create an image from a BMP file, I made this function, that return a resource like the others ImageCreateFrom function:



<?php

/*********************************************/

/* 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 enttes FICHIER

   $FILE = unpack("vfile_type/Vfile_size/Vreserved/Vbitmap_offset", fread($f1,14));

   if ($FILE['file_type'] != 19778) return FALSE;



 //2 : Chargement des enttes 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 : Cration 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;

}

?>

06-Jan-2005 05:30


This is how you can create a thumbnail with maximum height and width. This way it will fit nicely in a gallery table. In this example $im is the source image

<?

    //calculate thumb size

            $ow = imagesx($im);

            $oh = imagesy($im);

            $maxh = 100;

            $maxw = 150; 

            $new_h = $oh;

            $new_w = $ow;



            if($oh > $maxh || $ow > $maxw){

               $new_h = ($oh > $ow) ? $maxh : $oh*($maxw/$ow);

               $new_w = $new_h/$oh*$ow;

            }



            //create dst image

            $dst_img = ImageCreateTrueColor($new_w,$new_h);

            //resize and copy image

            ImageCopyResized($dst_img, $im, 0,0,0,0, $new_w, $new_h, ImageSX($im), ImageSY($im));    

            $function_image_new($dst_img,$galdir.$file);

?>

info at henrici dot biz
14-Aug-2004 01:27


To make the gd library available for Apache2/mod_php on Gentoo the following steps are required (and sufficient):

1) Add a USE flag for gd in "/etc/make.conf":

   USE="<other use flags> gd"

   A list of all of the USE flags can be found at: http://www.gentoo.org/dyn/use-index.xml

2) Re-emerge mod_php by executing "emerge mod_php"

3) Restart apache2 by executing "/etc/init.d/apache2 restart"



You need not uncomment the "extension=php_gd2.dll" line in "php.ini" as mentioned in a previous posting (since that line is only relevant for Windows).

cstevens at gencom dot us
21-Apr-2004 07:56


Here's how I resolved the "Fatal error: Call to undefined function: imagecreate()" error using Gentoo:



1) add a USE flag for gdb in /etc/make.conf

  

   USE="3dnow avi [whatever else you have] gdb"



   Note: here's a list of all of the USE flags:

   http://www.gentoo.org/dyn/use-index.xml



2) unmerged mod_php 



*Note* It could take awhile to "remerge" as it may need to compile several dependancies...do this during not production hours and have a backup if you absolutely cannot have downtime



   emerge -C mod_php



3) emerged mod_php



   emerge -p mod_php 

    # find out if it's going to take awhile



4) edit /etc/php/apach2-php4/php.ini

     uncomment the "extension=php_gd2.dll" line



5) Restart apache2



    /etc/init.d/apache2 restart



Hope this helps!



--

Cooper Stevenson

GenCom

http://www.gencom.us

foxlovr1 at cox dot net
13-Apr-2004 07:11


You can set it up so you can write a text which is controled from the URL.



Like this...



<?php

header("Content-type: image/png");

$im = @imagecreate(128, 16) or die("Cannot Initialize new GD image stream");

$bc = imagecolorallocate($im, 0, 255, 255);

$tc = imagecolorallocate($im, 0, 0, 0);

imagestring($im, 1, 4, 4,  $t, $tc);

imagepng($im);

imagedestroy($im);

?>



Then when you use the image, use this...



<img src="http://www.yourdomain.com/stuff/cool_image.php?t=Text">



This will create an image with a cyan background, and in black text it will say "Text"



EMail me at foxlovr1@cox.net or aquafox90@yahoo.com for comments/questions.

sjnorrie at hotmail dot com
04-Dec-2003 03:07


On windows.



When you get undefined function image* it means the gd library isnt being used. Check the php.ini file. Make sure the php_gd.dll isnt commented out. Restarting apache should result in the image functions working.

tassader at xmail dot cz
21-Oct-2003 11:55


It seems that imagecreate creates a grayscale image with gd2

tore at kyberheimen dot com
30-Aug-2002 05:33


GD UPGRADE PROBLEM:

I used imagecreate with gd 1.6 to make resized images of big photos. Then, when using the same script on gd 2.0, the colors got all wrong.

Using imagecreatetruecolor() fixed the problem!

php at silisoftware dot com
18-May-2002 01:17


Don't try and create an image with a really large width and/or height. First, $width x $height is (at least) the bytes of memory that need to be allocated. Secondly, if you exceed the range of int for either parameter, Apache crashes (before allocating any memory).

Don't ask how I figured this out ;)

robert at scpallas dot de
09-Feb-2002 12:09


The function ImageCreate() creates a PALETTE image.

The function ImageCreateFromJPEG() creates a TRUE COLOR image.



When you use GD 2.0 you will get an error when you try to use ImageCopy()

with one True color image and one Palette image.



Be sure to convert one of the images before using ImageCopy() or use ImageCreateTrueColor() instead of ImageCreate().

andrus at vnet dot ee
09-Jul-2001 12:09


Dont forget to use ImageDestoy after showed image. I forgot it, my webpage had about 15 pictures what was generated by GD and webserver died very fastly (server was Dual Xeon 900MHz and 4G RAM :[[ ). It died cos of not enough memory :\

wouter at rusman dot net
06-Jul-2001 08:31


to compile GD support on some linux distributions you have to include these with the ./configure command :


--with=gd=/usr --with-jpeg=/usr --with-png=/usr --with-zlib=/usr





(i had to include this on Redhat 6.1)


this becase the libraries are in /usr/lib instead of /lib

altype at bellsouth dot net
20-Apr-2001 07:13


ImagePNG($pic,"./dir/pic.png"); 





To save image as a file, I had to create a directory "dir" and CHMOD 777 to give read, write, and execute permission for everyone - or it wouldn't save it...

removethisbeforebayet at removethistooenseirb dot fr
09-Feb-2001 07:00


Pay attention to a problem I encountered.


Png images created with the PHP function seems to be very badly recognised by old browsers, especially -well, mainly - by IE 4.0 (crash of the browser).


I think this is probably due to the fact that, when IE 4.0 was released, the png format was either very recent, either not very used, because of the widespread jpeg and gif formats...


So, if you plan to dynamically create images for a web site to be seen by IE 4.0 users, think of it...


May'be the jpeg format will do the job better.

kim at kimmccall dot org
14-Dec-2000 08:22


How I fixed my "undefined function imagecreate()" problem:


I was having the same problem many have reported where most of PHP worked but the gd functions didn't.  I'd installed the RedHat rpm php-4.0.1pl2.  It said (phpinfo.php) that it had been configured with the '--with-gd=shared' option.  In my /usr/lib directory, I had both libgd.so.1.8.3 and libgd.a.  I decided to compile with the static library instead, so I downloaded the sources and built with all the same configuration flags except that I used --with-gd=/usr.  Now my gd library works!!!

rupert at complinet dot com
03-Aug-2000 03:19


one thing i've noticed is that if, after creating the image, you don't wash it with a background colour, shapes you create on top will 'bleed' to fill the image.

rolf dot winterscheidt at it-mannesmann dot de
25-Jul-2000 06:29


Since I needed some time to get something on my screen, here a small example of creating graphics:





<html>


<head>


</head>


<body>





<?php


$pic=ImageCreate(600,600);


$col1=ImageColorAllocate($pic,200,200,200);


$col2=ImageColorAllocate($pic,0,0,255);


ImageFilledRectangle($pic,1,1,100,100,$col2);


ImagePNG($pic,"pic.png");


ImageDestroy($pic);


?>


<img src="pic.png" border=0>


</body>


</html>





--


You create a color for the background ($col1, seems to be zero for the background) and one for the boxcolor. The image will be written to disk as pic.png and you get it via normal html-command "img src"... That's it.


Rolf

kb2ici at amsat dot org
29-Mar-2000 06:49


A sample php image program to create a clock





<?php


    header("Content-type: image/gif");





    $imSize        =    256;


    $clockSize        =    $imSize - 8;





    $today        =    getdate();


    $hour            =    $today[hours];


    $minutes        =    $today[minutes];


    $seconds        =    $today[seconds];


    if ($hour >= 12)


    {


        $hour    -=    12;


    }


    $hourDegress    =    $hour * 30;


    $hourDegress    +=    $minutes / 2;


    $minDegress    =    $minutes * 6;


    


    //*    the cordinate system stars at 3:00


    $hourDegress    -=    90;


    if ($hourDegress < 0)


    {


        $hourDegress    +=    360;


    }


    $minDegress    -=    90;


    if ($minDegress < 0)


    {


        $minDegress    +=    360;


    }


    


    //*    convert to radians


    $hourRadians    =    $hourDegress / 57.295779513082;


    $minRadians    =    $minDegress / 57.295779513082;


    


    $myImage        =    ImageCreate($imSize, $imSize);


    


    $white        =    ImageColorAllocate($myImage, 255, 255, 255);


    $black        =    ImageColorAllocate($myImage, 0, 0, 0);


//    $red            =    ImageColorAllocate($myImage, 255, 0, 0);


//    $green        =    ImageColorAllocate($myImage, 0, 255, 0);


    $blue            =    ImageColorAllocate($myImage, 0, 0, 255);





    ImageFill($myImage, 0, 0, $blue);


    Imageinterlace($myImage, 1);





    //*    draw the clock circle


    Imagearc($myImage, $imSize/2, $imSize/2, $clockSize, $clockSize, 0, 359, $white);





    //*    draw the hour hand


    $hourHandLen    =    ($clockSize / 2) * 0.6;


    $x2                =    $imSize/2 + ($hourHandLen * cos($hourRadians));


    $y2                =    $imSize/2 + ($hourHandLen * sin($hourRadians));


    ImageLine($myImage, $imSize/2, $imSize/2, $x2, $y2, $white);





    //*    draw the minute hand


    $minHandLen        =    ($clockSize / 2) * 0.9;


    $x2                =    $imSize/2 + ($minHandLen * cos($minRadians));


    $y2                =    $imSize/2 + ($minHandLen * sin($minRadians));


    ImageLine($myImage, $imSize/2, $imSize/2, $x2, $y2, $white);








    if ($minutes < 10)


    {


        $minutes    =    "0$minutes";


    }


    Imagestring($myImage, 3, 5, $imSize - 15, ($hour . ":" . $minutes), $white);





    Imagegif($myImage);





    Imagedestroy($myImage);


 


?>

phantom at t-p-l dot com
19-Feb-2000 03:11


after some experimenting I've come to the following concusions:


1) if you don't have GD when compiling PHP you have to recompile PHP to enable GD support..


2) imagepng() works the same way as imagegif() just creates png's ..


3) the first color you imagecolormatch becomes the background.. hmm.. 





hope this helps anyone =)

scott at mha dot ca
10-Feb-2000 03:49


okay .. listen .. if you are getting fatal errors attempting to use ImageCreate() then you most probably do not have GD installed .. Likewise, if you are getting fatal errors attempting to use ImageGIF() then you are most probably using a version of GD which does not support the GIF format.  Notice that in both of these examples that the problem has nothing to do with PHP or whether or not PHP "supports" any particular function.  You must have the GD image library installed to make images work.  It is as simple as that.  Furthermore, although current versions of GD do NOT support the GIF format, I know that old versions of GD (ie. version 1.3) do support the GIF format but they are probably illegal to use now because of the fuss that unisys has been making about it.

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