GD library does not work

Hello,

I am a complete beginner with php, please apologize stupid questions and erroneous posting , thanx

PHP5 and GD seems to be installed correctly in my system. I use Ubuntu Linux, 7.04, Apache2:

GD Support 	enabled
GD Version 	2.0 or higher
FreeType Support 	enabled
FreeType Linkage 	with freetype
FreeType Version 	2.2.1
T1Lib Support 	enabled
GIF Read Support 	enabled
GIF Create Support 	enabled
JPG Support 	enabled
PNG Support 	enabled
WBMP Support 	enabled

Code (markup):

My knowledge of php is poor, the following code has been copied from the web.

General php functions seem to work in my system, but I have problems with the GD library. The only reasonable thing I get is if I try:

$im = @ImageCreateFromJPEG ("IMG_001.jpg"); 
if(!$im) {
        $img_handle = ImageCreate (200, 20) or die ("Cannot Create image");
        $back_color = ImageColorAllocate ($img_handle, 0, 10, 10);
    $txt_color = ImageColorAllocate ($img_handle, 235, 235, 51);
        ImageString ($img_handle, 10, 25, 5,  "Image Not Found", $txt_color);
    ImagePng ($img_handle); }
Else {
    echo "GD library: Image is Found"; }

Code (markup):

The browser says:

GD library: Image is Found

Code (markup):

Problems start immediately with GD library. Issuing:

createthumb('IMG_001.jpg','tn_IMG_001.jpg',100,100);

Code (markup):

The browser says:

Fatal error: Call to undefined function createthumb() in /home/yngve/public_html/index.php on line 89

Code (markup):

Trying the following, the browser replies with garbage:

$height = 300;
$width = 300;
$im = ImageCreate($width, $height);
$bck = ImageColorAllocate($im, 10,110,100);
$white = ImageColorAllocate($im, 255, 255, 255);
ImageFill($im, 0, 0, $bck);
ImageLine($im, 0, 0, $width, $height, $white);
for($i=0;$i<=299;$i=$i+10) {
ImageLine($im, 0, $i, $width, $height, $white); }    
ImagePNG($im);

Code (markup):

The browser replies with garbage:

�PNG  ��� IHDR��,��,���C�6���PLTE nd������� EIDATh�Ř_h��g�3S�쎒�1]�#E6M�0�Z�a�lb�@)

Code (markup):

So, please, any advice is appreciated.
According to the phpinfo() GD, is installed properly on my Linux Ubuntu Feisty Fawn 7.04, Apache2.
However using GD functions there seems to be a problem. On the other hand, pdp commands outside GD seems OK.

Thanx a lot.

 

createthumb() is not a PHP function. It probably has been defined somewhere on the page where you found the rest of the code.

And the garbage is actually your image. The reason you cannot see it properly is because you're not sending the appropriate content type header.

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

PHP:

 

Thanx a lot for the quick and clear reply. However, there is still a problem. When I include the code suggested I get an error message. The error message suggests that "header is already sent". I therefore move the code suggested to the start of the file. I put the following code on line 4:

<? header('Content-Type: image/png'); ?>

Code (markup):

However, the browser replies:

Warning: Cannot modify header information - headers already sent by (output started at /home/yngve/public_html/index.php:4) in /home/yngve/public_html/index.php on line 4

Code (markup):

The code producing garbage is this:

$height = 300;
$width = 300;
$im = ImageCreate($width, $height);
$bck = ImageColorAllocate($im, 10,110,100);
$white = ImageColorAllocate($im, 255, 255, 255);
ImageFill($im, 0, 0, $bck);
ImageLine($im, 0, 0, $width, $height, $white);
for($i=0;$i<=299;$i=$i+10) {
ImageLine($im, 0, $i, $width, $height, $white); }    
ImagePNG($im); 

Code (markup):

(I removed createthumb(), of course.)

And the image still comes out as garbage characters. Greatful for further advice

 

Make sure you call the header() function before sending ANY output to the browser. No HTML, no white spaces, nothing...

 

Thanks for having the patience with a n00b

You are quite right, of course, the problem is not in the GD library. When I just put header and the drawing commands in a separate file, it gives a nice picture. it seems I have not yet understood how to enter the php-GD library code into my HTML.

The start of my file now looks like this.

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
[COLOR="Red"]<? header('Content-Type: image/png'); ?>[/COLOR]

	<META HTTP-EQUIV="CONTENT-TYPE" CONTENT="text/html; charset=utf-8">
	<TITLE></TITLE>
	<META NAME="GENERATOR" CONTENT="OpenOffice.org 2.2  (Linux)">
	<META NAME="CREATED" CONTENT="20070704;17040300">
	<META NAME="CHANGEDBY" CONTENT="auth">
	<META NAME="CHANGED" CONTENT="20070705;9455500">
	<STYLE TYPE="text/css">
	<!--
		@page { size: 21cm 29.7cm; margin: 2cm }
		P { margin-bottom: 0.21cm }
	-->
	</STYLE>
</HEAD>

Code (markup):

However, I still get:

Warning: Cannot modify header information - headers already sent by (output started at /home/yngve/public_html/index.php:4) in /home/yngve/public_html/index.php on line 4

Code (markup):

 

Read my post again - send the header BEFORE sending ANY output to the browser.

This:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>

HTML:

... is HTML.


But then again, you cannot inset images the way you're trying to do it. You have t make a separate file which ONLY sends the image data, and include this using the HTML <img> tag.

<img src="script.php" />

HTML:

 

That did it! I can only extend my deepest thanx and a virtual beer to nico_swd. Now the picture appears on the screen.

You really saved me a lot of time! This forum rocks.

(I tried to put the <? header('Content-Type: image/png'); ?> on the very first line of the file, but got another error message. - Sorry, I forgot that one.)


My only small question now does not belong to this thread and I may come back about it if I don't solve it: Why does the picture appear on the right hand edge of the screen?

However, if there is a simple answer to that one too, please shoot!

$height = 300;
$width = 300;
$im = ImageCreate($width, $height);
$bck = ImageColorAllocate($im, 10,110,100);
$white = ImageColorAllocate($im, 255, 255, 255);
ImageFill($im, 0, 0, $bck);
ImageLine($im, 0, 0, $width, $height, $white);
for($i=0;$i<=299;$i=$i+10) {
ImageLine($im, 0, $i, $width, $height, $white); }    
ImagePNG($im);

Code (markup):

Thanx again !