creating image with php problem - php

my index.php file i have somethingk like :
<?php
session_start();
$_SESSION[some_value] = 1;
?>
<img src="image.php" alt="some image"/>
<?php
$_SESSION[some_value] = 0;
?>
my image.php file i have look like ( basic code ) :
<?php
session_start();
header("Content-Type: image/png");
$im = #imagecreate(400, 20)
or die("Cannot Initialize new GD image stream");
$background_color = imagecolorallocate($im, 255, 255, 255);
$text_color = imagecolorallocate($im, 233, 14, 91);
imagestring($im, 1, 5, 5,"session value is : {$_SESSION[some_value]}", $text_color);
imagepng($im);
imagedestroy($im);
?>
Now, when i load my index.php page in browser the value in image is session value is : 0, how to make it to show 1 and then code in index.php to set it to 0 ( adding in image.php code to set value to 0 is not what i'm looking for )

You run into problems because in your code both scripts do not share the memory of the session even if both are using the $_SESSION array.
That's by the nature of how and when PHP stores the values of the $_SESSION array.
Instead you need a shared store like a database or shared memory to exchange values between your scripts.

The problem is that the browser loads image.php after index.php is loaded.
You can do something like this:
<img src="image.php?some_value=<?php echo $_SESSION[some_value]; ?>" alt="some image"/>
But it depends on your particular purpose.

Related

PHP failure: imagejpeg and imagecreatefromjpeg

I check StackOverflow to see if this question has been answered, but didn't find anything corresponding to this.
Running Wampserver 3/Apache 2.4.18/PHP 7.0.4/MySQL 5.7.11. This simple example that I copied from StackOverflow doesn't work -- no image is displayed. Extension php_gd2 is enabled (get_extension_funcs("gd") shows the list).
I had to comment out the header(); code (even if I put it at line 2), because Firefox complained the code is incorrect with it.
<?php
// Create a blank image and add some text
$im = imagecreatetruecolor(120, 20);
$text_color = imagecolorallocate($im, 233, 14, 91);
imagestring($im, 1, 5, 5, 'A Simple Text String', $text_color);
// Set the content type header - in this case image/jpeg
//header('Content-Type: image/jpeg');
// Output the image
imagejpeg($im);
// Free up memory
imagedestroy($im);
?>
If I try to load in image from a file:
<?php
$thumb = imagecreatefromjpeg("http://localhost/newthumb.jpg");
if( imagejpeg($thumb)){
imagedestroy($thumb);
echo "<br>Image2 created";
}
else {
echo "<br>Image2 not created";
}
?>
I get what is tantamount to a character dump of the file (the # are black diamonds with ? in them):
####JFIF##>CREATOR: gd-jpeg v1.0 ...
Image2 created
What the !##$! happened with the new Wampserver/Apache/PHP/MySQL??? What does it take to get images to display in PHP?

Image with text not working and add some Html

I want to upload an image with some text on it, but when I'm uploading my PHP script it's not working with an image, it shows error every time. And also i want to add some html in the same file I had tried to put that php In html tag and show that image in the center how to do so
My PHP code is:
result.php
<?php
header('Content-type: image/jpeg');
$jpg_image = imagecreatefromjpeg('image.jpg');
$white = imagecolorallocate($jpg_image, 255, 255, 255);
$font_path = 'font.TTF';
$text = $_GET["name"];
imagettftext($jpg_image, 25, 0, 75, 300, $white, $font_path, $text);
imagejpeg($jpg_image);
imagedestroy($jpg_image);
?>
$_GET["name"]; is used for getting text form HTML by input tag, and for your information I have used form method to get the text I want an working example.
The image I want to use is http://images.visitcanberra.com.au/images/canberra_hero_image.jpg
So please use that image only while giving answer
this line will describe the name of image $jpg_image = imagecreatefromjpeg('image.jpg'); and image name is image.jpg
as you mentioned The image I want to use is http://images.visitcanberra.com.au/images/canberra_hero_image.jpg
this is image name canberra_hero_image.jpg right, how come php will work, first rename and use single name
better rename you php
this is the reason you see only text and not image
Change your code from '$jpg_image = imagecreatefromjpeg('image.jpg');' to this code
$image_path = ''http://images.visitcanberra.com.au/images/canberra_hero_ima‌​ge.jpg'';
$jpg_image = imagecreatefromjpeg($image_path);

Does html can be use with dynamic generated images in php?

I am using this code to create an image
<?php
// Set the content-type
header('Content-Type: image/png');
// Create the image
$im = imagecreatetruecolor(400, 30);
// Create some colors
$white = imagecolorallocate($im, 255, 255, 255);
$grey = imagecolorallocate($im, 128, 128, 128);
$black = imagecolorallocate($im, 0, 0, 0);
imagefilledrectangle($im, 0, 0, 399, 29, $white);
// The text to draw
$text = 'Testing...';
// Replace path by your own font path
$font = 'arial.ttf';
// Add some shadow to the text
imagettftext($im, 20, 0, 11, 21, $grey, $font, $text);
// Add the text
imagettftext($im, 20, 0, 10, 20, $black, $font, $text);
// Using imagepng() results in clearer text compared with imagejpeg()
(A)print ('<div class="test">');
imagepng($im);
print ('</div>');
(B)imagedestroy($im);
?>
The code work fines if i comment the line number 'A' and 'B' and it generates the image on the browser with testing written on it. But i want the image to be in a div. so i uncomment the line (A) and (B) but it is not giving right output. The generated html is also strange generated html is
<img src="http://localhost/php/test92.php" alt="The image “http://localhost/php/test92.php” cannot be displayed, because it contains errors.">
Basically, to create dynamic image in HTML, you will need 2 PHP files:
one for the image itself
another one for PHP to display it.
Let's take a look how to do it:
You create image.php that accept parameter, like: image ID or file name. For security reason, you HAVE to filter whatever parameter it get.
Why you have to do this? because, to generate image, you can't mix it with another HTML output. Let alone a single space or return as this will render the image broken.
You do the HTML thing on another PHP, say test92.php. To the HTML logic here, like:
get image data
loop the data
display image => <img src="image.php?imageID=12" alt="" />
If you want a div around your image you have to do that in the html, you can't do that in the image generation code
<div>
<img src="http://localhost/php/test92.php">
</div>
If you are getting errors regarding the image, try browsing the image url http://localhost/php/test92.php and see what it looks like.
Does it show an image like you are expecting?

PHP header, Content type: image not allowing text

I have a variable ($output) that is set to a string.
To mekt this string an image I'm using the PHP: GD Library.
In particular the imagestring() function, which I'm using with a very slight modification:
<?php
// Create a 100*30 image
$im = imagecreate(100, 30);
// White background and blue text
$bg = imagecolorallocate($im, 255, 255, 255);
$textcolor = imagecolorallocate($im, 0, 0, 255);
// Write the string at the top left
imagestring($im, 5, 0, 0, $output, $textcolor); #here is my string $output
// Output the image
header('Content-type: image/png');
imagepng($im);
imagedestroy($im);
?>
This is working as expected: It turns $output into an image.
So, my problem is (or my best guess at least):
header('Content-type: image/png');
Which, doesn't allow me to output any html after that.
So I read this question, which asks if you can use two headers, which you can't, but the accepted answer recommends, something like this: <img src="my_img.php" />
This of course would be fine, except I don't know how would this solve my issues since, since even if I knew the source to this image (which I don't - so, that would be my first question, what's the path to the generated image*) I't would change the fact that the header is there and is not letting me output text.
So, I how would you approach this issue?
Thanks in advance!!
*I guess that would solve my issues since I could do this on an external file, and the just call the image (but maybe not since I would have to do an include and this would include the header too) as you see I'm a bit confused. Sorry :)
UPDATE:
So I'm seeing my question was confusing so I will add some more code to see if this clarifies my problem a little bit more:
<?php
$x = mt_rand(1,5);
$y = mt_rand(1,5);
function add($x, $y) { return $x + $y; }
function subtract($x, $y) { return $x - $y; }
function multiply($x, $y) { return $x * $y; }
$operators = array(
'add',
'subtract',
'multiply'
);
$rdno = $operators[array_rand($operators)];
$result = call_user_func_array($rdno, array($x, $y));
session_start();
$_SESSION['res'] = $result;
if ($rdno == "add") {
$whato = "+";
}elseif ($rdno == "subtract") {
$whato = "-";
} else {
$whato = "*";
}
$output = $x . $whato . $y . " = ";
?>
<form name="input" action="check.php" method="post">
<input type="text" name="result" />
<input type="submit" value="Check" />
</form>
I want $output to be a image so this got me trying to use the PHP:GD script above, but I can't make put in the same file because of the header.
You need to make a separate PHP script which serves the image, then make an <img> tag that points to this script.
You can send information to the script using the querystring in the image URL.
Morbo says: "Windmills do not work that way! Goodnight!"
Which means that you need to bone up on how this all works. This issue points to you having a basic misunderstanding of your tools. HTML can't contain images, it contains links to images. So your script needs to be included from another page via an image tag. (or CSS)
However, all this is a good thing. It means that this script can have dynamic elements that produce a new image each time it is called. Or that it could password-protect your images so only logged-in users can see it.
There are a host of ways to use this. And once you realize the image is like a page to php, this opens new routes. Php can output anything. Word docs, excel, pdf, css, even JS. all of which can be used to do cool things.
Just think of the image as a separate page. You'll get it. It'll just click into place in your mind. One of those big 'aha' moments.
First, the path.
From the manual :
imagepng ( resource $image [, string $filename [, int $quality [, int $filters ]]] )
It means that if you don't give a second argument (it is the case here), you don't have the path to a file but the data of the file / image ressource. The php file will be understand as a png file by the browser thanks to the header you give.
Second :
In your page (ie index.php), you could add this like that
<img src="myimg.php?output=[...]" />
and in your php script myimg.php you have it like this :
<?php
$output = $_GET['output'] // getting your text
// Create a 100*30 image
$im = imagecreate(100, 30);
// White background and blue text
$bg = imagecolorallocate($im, 255, 255, 255);
$textcolor = imagecolorallocate($im, 0, 0, 255);
// Write the string at the top left
imagestring($im, 5, 0, 0, $output, $textcolor); #here is my string $output
// Output the image
header('Content-type: image/png');
imagepng($im);
imagedestroy($im);
?>
2 separates files.
You can send the image inline with echo '<img src="data:image/png;base64,'. base64_encode(imagepng($im)) .'" /> instead of <img src="my_img.php">.
Do not set a content-type header! Your output is text/html what you don't have to announce as it's the default in most server setups.
HTTP doesn't work that way. When your are serving image/png data, it as if you are serving a png file from the site, not an html file with an image in it. What are you trying to accomplish?
my_img.php is not source to your image. It is a source to the script generating that image, or reading it from file and outputting directly into browser. Obviously the approach with img src would be the best, because you'll hide all "boring" implementation of displaying image string behind browser's mechanisms.

Pass variable from image to next page

Hey I have dynamic image begin created with imagecreate(), and I have random values being produced, and I want to pass that random number, to a variable, and use that variable inside the page where Im using the image source.
The image is on random.php, and Im using <img src="random.php" /> on page index.php if that matters, and I want to pass from random.php (the image), to index.php. I already tried sessions and cookies but when I refresh, its always 1 step behind what the image is producing...
Im using a for loop to echo random numbers, I need to pass those numbers to a variable. Basicly how do I get numbers outside an image, in real time, not 1 step back.
What about using a temporary session variable?
On your first page,
<?php
session_start();
$_SESSION['mykey'] = 'myrandomval';
session_write_close(); // Helpful if you're using a header redirect
?>
and on the second page
<?php
session_start();
$value = $_SESSION['mykey'];
?>
The problem you are having is that index.php is requested, then the browser realizes that random.php is needed, so- yes, random.php will be a step AFTER index.php...
If you switch your "random creation" logic around, (have index create the key stored in a session, which can then be read from random.php) it may solve your problem.
Instead of passing variables from the page to the image, you could set the random number generator seed to the same value on both scripts. Here is a full sample:
<?php
function randomcolor()
{
srand( $_SERVER['REQUEST_TIME'] );
$colors = array('red', 'green', 'blue', 'black', 'orange');
return $colors[ array_rand($colors) ];
}
$color = randomcolor();
if(isset( $_GET['image'] ))
{
header('Content-type: image/png');
$im = imagecreate(75, 50);
imagecolorallocate($im, 0xee, 0xee, 0xee);
$black = imagecolorallocate($im, 0, 0, 0);
imagestring($im, 2, 10, 10, $color, $black);
imagepng($im);
exit;
}
?>
<p>color: <?php echo $color; ?></p>
<img src="test5.php?image=1" />
This is two separate requests being seeded with the REQUEST_TIME, which means array_rand will return the same value both times.

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