display image stored in database - php

I have images that are base64 encoded as blobs in my sql database.
using a php script I can properly display the picture in my browser using.
echo '<img src="data:image/jpeg;base64,' . $fetch_row['object']. '" />';
however, I would like to create a view that would display the photo directly or by accessing the php file and returning the picture in a column. I have tried using something like: in mysql
concat('<img src="data:image/jpeg;base64,',`object`,'" />')
or concat('<img src=/image.php? blah blah blah)
any ideas?

<?php
header('Content-type: image/jpeg');
echo base64_decode($fetch_row['object']);
Your question also exactly typifies why storing images in the database is a BAD idea. If the image was just a file on your server's drive, you could just have
<img src="/path/to/file.jpg" />
and not have to involve the DB/PHP layer at all. As it stands now, your data-uri version prevents the browser from caching that image at all, and you'll be forcing the user to download that image EVERY time, burning up their (and your) bandwidth.

Related

php delete image from server after upload & display

Sending an image in my php form, it gets saved onto my server and at the
action.php page it gets displayed. Now when I try to:
echo '<div id="image"><img src="'.$target_path.'" width="280" height="280"></div>';
it works just fine... but if I add unlink($target_path); at the end of my php code it
will not even display the image even though it gets deleted AFTER displaying the image...
So the question is, how can I display the image and deleting it at the same time so my server does not gets stuffed with user pictures?
Try another thing: output the image base-64 encoded.
$contents = file_get_contents($file);
$base64 = base64_encode($contents);
echo '<div id="image"><img src="data:image/jpg;base64,'.$base64.'" width="280" height="280"></div>';
(instead of move_uploaded_file() etc, use as $file variable the $_FILES[...]['tmp_name'])
You can achieve this by creating a little script that gets the image-filename and will delete it after it has been retrieved:
<?php
$file = image_file_from_parameter($_GET['image']);
headers_for_file($file);
readfile($file);
unlink($file);
In your HTML output you then link to that script:
<img src="path/to/image.php?image=893sudfD983D" />
If you set nice caching headers, the user won't notice that your server did serve the file only once.
When you echo the url of an image with img src you're just sending the browser the url of an image, not the actual image data. The image needs to remain on the server if you want it to be viewable by this approach.
You could use bwoebi's solution to pass the actual image data instead of a link, but a better solution is just to keep the images on the server and periodically delete old files.

Display user input image without saving it to a folder

How can I display an image and pass it as an input parameter in an executable in php without saving the image in a folder. The user gives the image path as input and I am using ajax to display the image when it is selected when I save it to a folder it works but how can I display it without saving it in a folder? My code now is
move_uploaded_file($_FILES["file"]["tmp_name"],"upload/".$_FILES["file"]["name"]);
//echo "Stored in "."upload/".$_FILES["file"]["name"];
echo "<img src='upload/".$_FILES["file"]["name"]."' class='preview'>";
I tried
<img src=$_FILES["file"]["tmp_name"]. class='preview'>
but it didnt work. As I will have thousands of input from thousands of user I dont want to save it. Is there any optimised and efficient method to do this?
I think, its not possible to show image without saving it. You could try to save the image in temp folder on the server side and clean this folder periodically to avoid much space consumption.
The src attribute of the <img> tag should be an URL accessible by the client.
You try to give a local path (ex: path/to/your/file.jpg) of a temporary file as URL, it will not working.
info: The uploaded image is save on the local disk on a temp directory, and could be deleted by PHP later.
If you want to show the image without moving it at a place reacheable by a URL, you can try to load its content as base64 content
$imagedata = file_get_contents($_FILES["file"]["tmp_name"]);
$base64 = base64_encode($imagedata);
and use in your HTML
<img src="data:image/png;base64, <?php echo $base64; ?>" />
I don't think you can show the image without saving it.
You need to save the file either to the filesystem or to memory if you want to later output
Your problem here is that $_FILES only exists in the script that the image was sent to. so when you initiate another http request for img source, php no longer has any clue what file your trying to read.
You need a way to tell which image to be read on http request.
One thing you can do is that you can save the file in a place accessible by the client and then just have php delete it after you output it. So once the image is outputted it will be deleted and no longer be existing in the file system.
Another approach would be to get the image from the memory by directly writing the contents to httpresponse.
You can do this way
$image = file_get_contents($_FILES["file"]["tmp_name"]);
$enocoded_data = base64_encode($image);
and when you show your image tag :
<img src="data:image/png;base64, <?php echo $enocoded_data ; ?>" />
Hope any of these helps you

Display image from sql

I've create a table where I've saved images through "BLOB". I need to show those images along with other items. But I don't know how to show those images together in the same page.
Here's my php code that displays other things in form of a table. Similarily, I wanted to display images accordingly. Any help?
<?php
$display_query = mysql_query("SELECT * FROM eportal");
echo "<table id='pageTable'><thead><tr><th>Item code</th><th>Description</th><th>Cost</th></tr></thead>";
echo "<tbody>";
while($row = mysql_fetch_array($display_query)){
print "<tr><td>".$row['itemid']."</td><td>".$row['description']."</td><td>";
print "₹".$row['cost']."</td></tr>";
}
echo "</tbody>";
echo "</table>";
mysql_close($connection);
?>
Saving images to the DB is not a good idea but if You think You need to it this way, then You can retrieve the data from DB table, encode it to base64 (http://php.net/base64_encode) and then in HTML print it in this way:
<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Red dot">
Using PHP You would write:
echo '<img src="data:'.$image_mime_type.';base64,'.base64_encode($image_data_from_db).'" alt="My image alt" />';
As other people mentioned, storing the images in the database is usually a bad idea.
Images are not transmitted in the same HTTP response with another page data.
To show images from the database, you would need to implement a script which, given the item id, would read the field and send the image's binary data; and provide the path to the script in your form's <img src="">:
while($row = mysql_fetch_array($display_query)){
print "<tr><td>".$row['itemid']."</td><td>".$row['description']."</td><td>";
print "₹".$row['cost']."</td><td>";
print "<img src=\"image.php?id=".$row['id']."\"></td></tr>";
}
image.php is another script which outputs the value of image_blob given the eportal.id. You would also need to provide correct size and mime type in the headers.
You better just store the images in a file (accessible by the web server) and store the path fo the file in the database.
Read the Blob data and write it into the file with header type image.. and try to print it, It should display the image file.
And yes saving image or any file in DB is really a bad habit as you are increasing DB size and it slowdown the performance also.. I suggest you to just try to convert you Blob into Image but don't apply in your work. Just save the image at desired location and keep its location path into DB to fetch and save next time.
The debate of storing blobs versus storing a path to the image file on disk has been debated over and over again. Microsoft provides a research paper comparing the pros and cons of each here. With that said, to display a blob as an image you need to make a call to a separate page and output header information that tells the browser what type of image is stored.
For example:
connectToDatabase();
$sql = "SELECT image_blob FROM eportal;";
$result = mysql_query($sql) or die(mysql_error());
$row = mysql_fetch_array($result);
header("Content-type: image/jpeg");
echo $row['image_blob'];
$db->close();
In case you still want to save your images in database, you will need second script which will get those images from database and pass them to browser with correct headers.
header("Content-type: image/jpeg");
#
# Replace this with database read:
# readfile('myimage.jpg');
Also, you will need to store what kind of image u use. There will be different header for JPEG, GIF or PNG file.

In PHP, how I show various images from a BLOB field in the database with the HTML content?

I stored it images in the database using an BLOB field (I'm using SQLite). Now I want to recover this image to a HTML page and show the images there.
I can retrieve the binary data from the image from the database, but what I can do to transform this data in an image and show in the page? Currently I want to show the images inside a field in a table.
You could abuse the data: protocol, but trust me, you don't want that if you can avoid it. Normally, you create a separate php-script that serves images, so in script 1:
<img src="/myimagescript.php?id=1234">
In myimagescript.php:
//get the data from the database somehow (mysql query et al.)
//let's assuma the data is in $data
header('Content-Type: image/jpeg');//alter for png/gif/etc.
echo $data;
#uscere90 is right, but an example might help (example of a PNG image):
<?php
header("Content-type: image/png");
echo $image_data;
?>
Typically this is done by creating a wrapper script or function that retrieves the BLOB and delivers it with the appropriate content headers to be used as an <img src=''>
Doing it this way also gives you the benefit of being able to deliver or not deliver the image based on other authentication factors determined by your PHP. If, for example, a user doesn't have permission to see an image, you can instead show some default or blocking image in its place.
// File getimg.php
// Retrieve the image blob specified by $_GET['imgid'] from the database
// Assuming your blob is now in the variable $image...
header("Content-type: image/jpeg");
// Just echo out the image data
echo $image;
exit();
Now in your html:
<img src='getimg.php?imgid=12345' alt='this is your img from the database' />
You can create a simple image.php page that queries your database, then prints out a content-type relevant to the image and vomits the binary data to screen. So, in your table, you'd have <img src=image.php?id=something />, and then you'd use that id in your image.php page to do your database lookup, retrieve the binary data, and print it to screen after printing the content-type header.
image.php:
<?php
header('Content-type: image/jpeg');
//DO SQL NINJA STUFF HERE
echo mysql_result($result,0,"file_content");
?>
There are two options I would say:
You create a script that returns the image data. The <img src="-field then calls that script.
You offer the data of the images directly via a data url.
Both have it's pros and cons. For the first solution you must create a new script for the images. The second method will bloat your page if the images are large.
As there are examples for the image script method already, here is some code fragment for data URIs:
<?php
function data_uri($content, $mime)
{
$base64 = base64_encode($content);
return ('data:' . $mime . ';base64,' . $base64);
}
?>
<img src="<?php echo data_uri($content,'image/png'); ?>" />
You need to set the mime-type according to your image, image/png for PNG images, image/jpeg for JPG files etc., see here for a list.

How to display an Image from a mysql blob

I am trying to display an image from a MySQL blob field. I have tried a few different things and none of them seem to work.
I have tried:
header("Content-type: $type"); img src = $blobData;
header("Content-type: $type"); echo($blobData);
<?php
header("Content-type: $type");
echo $blobData;
?>
This code looks perfectly OK. However, I heard a similar complain from another person and I was able to troubleshoot it by assuring that:
The php script does not output any extra character before or after sending the binary image data.
The php script is saved as a pure ASCII text file, not as a Unicode/UTF-8 encoded file. The Unicode/UTF-8 encoded PHP files might include a signature as the first bytes. These bytes will be invisible in your text editor but server will send these few extra bytes to the browser before the JPEG/GIF/PNG data. The browser will therefore find the wrong signature in the beginning of data. To workaround, create a blank text file in notepad, paste in the php code and save the file in ANSI encoding.
Another option you might consider (assuming you are on Apache):
Create an .htaccess file with a mod_rewrite for all image extensions (png, jpg, gif).
Have it redirect to a php script that looks up the image requested in the DB. If it is there, it echos out the header and BLOG. If it isn't there, it returns a standard 404.
This way you can have:
<img src="adorablepuppy.jpg" />
Which then gets redirected ala:
RewriteEngine on
RewriteRule \.(gif|jpg|png)$ imagelookup.php
This script does a query for the image, which (obviously) assumes that the requested image has a unique key that matches the filename in the URL:
$url = $_SERVER['REQUEST_URI'];
$url_parts = explode("/", $url);
$image_name = array_pop($url_parts);
Now you have just the image filename. Do the query (which I shall leave up to you, along with any validation methods and checks for real files at the address, etc.).
If it comes up with results:
header('Content-type: image/jpeg');
header('Content-Disposition: inline; filename="adorablepuppy.jpg"');
print($image_blog);
otherwise:
header("HTTP/1.0 404 Not Found");
FYI: I have no idea if this would be bad in terms of performance. But it would allow you to do what I think you want, which is output the image as though it were a flat image file on the server using a simple image element. I'm inclined to agree that BLOBs are not the best way to go, but this does avoid any cross-browser issues.
I believe that the issue that you are encountering is an issue with encoding. This resource claims that you can use the print function.
Just get the image from the database. And print it using the correct headers.
$image = mysql_fetch_array(...)
header("Content-type: image/jpeg"); // change it to the right extension
print $image['data'];
For performance reasons... this is not advisable. There are several reasons to put images in databases but the most common are:
a) keeping them indexed (duh!)
You can do this by storing the images flat on the server and just indexing the image filename.
b) keeping the image hidden/protected
Flickr and alike still store the images flat on the server and use a different approach. They generate a URL thats hard to find.
This link points to a protected image on my account. You can still access it once you know the correct URL. Try it!
farm2.static - a farm optimized for delivering static content
1399 - perhaps the server
862145282 - my username
bf83f25865_b - the image
In order to find all my secret images any user can hard hit Flickr with the above address and change the last part. But it would take ages and the user would probably be blocked for hammering the server with thousands of 404s.
That said there is little reason to store images on BLOBs.
Edit:Just a link pointing to someone that explained much better than I did why BLOB is not the way to go when storing images.

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