check if image is accessable - php

i got image url saved in my database.i am using php and mysql.
Some images can be displayed but others are restricted.At the moment restricted image show up broken on my site.
I only which to display non restricted images.
url for image that can be shown is
http://images.icecat.biz/img/gallery/16678932_9061.jpg
restricted image is
http://images.icecat.biz/img/gallery/8622798_7908.jpg
i have tried getimagesize but cant seem to be having any luck.
kind regards
nafri

file_exists() doesn't work across domains. Server side can be done like:
$url = 'http://images.icecat.biz/img/gallery/16678932_9061.jpg';
$header = get_headers($url, 1);
if(strpos( $header[0],'200') === false){
// do what ever
}
EDIT: fixed for 200 response. Better use curl though, faster it is

If you're happy to handle this on the client side, then you could use javascript to deal with this:
You can use handle the onError event to replace the image or do something else in the event that the image cannot be displayed.
See this answer for an example.

Related

Fastest method to get the screenshot image of an external webpage

Hi,
I want to get the screenshot of several pages and display them on my website. As of now, I am using the method below:
<?php
$site = $screenurl;
$image = file_get_contents("https://www.googleapis.com/pagespeedonline/v1/runPagespeed?url=$site&screenshot=true");
$image = json_decode($image, true);
$image = $image['screenshot']['data'];
$image = str_replace(array('_','-'),array('/','+'),$image);
echo "<img src=\"data:image/jpeg;base64,".$image."\" alt=\"\">";
?>
but with 10 or more images per page, this method takes FOREVER to load them all or it wont even load them at all because it times out. I would like to know a more effective, optimized and faster way to do this.
Thank you.
Not sure if this is exactly what you're looking for, but PHP's built-in (PHP >= 5.2.2) imagegrabscreen function is capable of returning an image resource containing a screenshot of the whole screen. It is sort of picky, though, from what I understand (never used it myself), requiring it to be run on a Windows system and "allow Apache service to interact with the desktop". These documentation pages could be helpful:
imagegrabscreen Function
imagegrabwindow Function

PHP: Displaying an image from a web service

I'm using an external web service that will return an image URL which i will display in my website, For example :
$url = get_from_web_service();
echo '<img url="'.$url.'" />';
everything is working fine except if i have 100 images to show then calling the web service become time & resources consuming.
//the problem
foreach($items as $item) {
$url = get_from_web_service($item);
echo '<img url="'.$url.'" />';
}
So now i'm considering two options:
//Option1: Using php get_file_contents():
foreach($items as $item)
{
echo '<img url="url_to_my_website/get_image.php?id='.$item->id.'" />'
}
get_image.php :
$url = get_from_web_service($id);
header("Content-Type: image/png");
echo file_get_contents($url);
//Option2: Using ajax:
echo '<img scr="dummy_image_or_website_logo" data-id="123" />';
//ajax call to the web service to get the id=123 and get the url then add the src attribute to that image.
THOUGHTS
First option seems more straight forward, but my server might be
overloaded and involved in every single image request.
Second option it's all done by browser & web service so my server is not involved at all. but for each image i'm making 2 calls 1 ajax call to get the image URL and another one one to get the image. so loading time might be vary and ajax calls might fail for large number of calls.
Information
Around 50 Images will be displayed in that page.
This service will be used by around a 100 user at a given time.
I have no control over the web service so i can't change its functionality and it doesn't accept more than 1 image ID for each call.
My Questions
Any better option i should consider?
If not, which option should I follow? and most important why i should follow that one?
Thanks
Method 1: Rendering in PHP
Pros:
Allows for custom headers that're independent of any server software. If you're using something that's not generally cached (like a PHP file with a query string) or are adding this to a package that needs header functionality regardless of server software, this is a very good idea.
If you know how to use GD or Imagick, you can easily resize, crop, compress, index, etc. your images to reduce the image file size (sometimes drastically) and make the page load significantly faster.
If width and height are passed as variables to the PHP file, the dimensions can be set dynamically:
<div id="gallery-images">
<noscript>
<!-- So that the thumbnail is small for old mobile devices //-->
<img src="get-image.php?id=123&h=200&w=200" />
</noscript>
</div>
<script type="text/javascript">
/* Something to create an image element inside of the div.
* In theory, the browser height and width can be pulled dynamically
* on page load, which is useful for ensuring that images are no larger
* than they need to be. Having a function to load the full image
* if the borwser becomes bigger isn't a bad idea though.
*/
</script>
This would be incredibly considerate of mobile users on a page that has an image gallery. This is also very considerate of users with limited bandwidth (like almost everyone in Alaska. I say this from personal experience).
Allows you to easily clear the EXIF data of images if they're uploaded by users on the website. This is important for user privacy as well as making sure there aren't any malicious scripts living in your JPGs.
Gives potential to dynamically create a large image sprite and drastically reduce your HTTP requests if they're causing latency. It'd be a lot of work so this isn't a very strong pro, but it's still something you can do using this method that you can't do using the second method.
Cons:
Depending on the number and size of images, this could put a lot of strain on your server. When used with browser-caching, the dynamic images are being pulled from cache instead of being re-generated, however it's still very easy for a bot to be served the dynamic image a number of times.
It requires knowledge of HTTP headers, basic image manipulation skills, and an understanding of how to use image manipulation libraries in PHP to be effective.
Method 2: AJAX
Pros:
The page would finish loading before any of the images. This is important if your content absolutely needs to load as fast as possible, and the images aren't very important.
Is far more simple, easy and significantly faster to implement than any kind of dynamic PHP solution.
It spaces out the HTTP requests, so the initial content loads faster (since the HTTP requests can be sent based on browser action instead of just page load).
Cons:
It doesn't decrease the number of HTTP requests, it simply spaces them out. Also note that there will be at least one additional external JS file in addition to all of these images.
Displays nothing if the end device (such as older mobile devices) does not support JavaScript. The only way you could fix this is to have all of the images load normally between some <noscript> tags, which would require PHP to generate twice as much HTML.
Would require you to add loading.gif (and another HTTP request) or Please wait while these images load text to your page. I personally find this annoying as a website user because I want to see everything when the page is "done loading".
Conclusion:
If you have the background knowledge or time to learn how to effectively use Method 1, it gives far more potential because it allows for manipulation of the images and HTTP requests sent by your page after it loads.
Conversely, if you're looking for a simple method to space out your HTTP Requests or want to make your content load faster by making your extra images load later, Method 2 is your answer.
Looking back at methods 1 and 2, it looks like using both methods together could be the best answer. Having two of your cached and compressed images load with the page (one is visible, the other is a buffer so that the user doesn't have to wait every time they click "next"), and having the rest load one-by-one as the user sees fit.
In your specific situation, I think that Method 2 would be the most effective if your images can be displayed in a "slideshow" fashion. If all of the images need to be loaded at once, try compressing them and applying browser-caching with method 1. If too many image requests on page load is destroying your speed, try image spriting.
As of now, you are contacting the webservice 100 times. You should change it so it contacts the webservice only once and retrieves an array of all the 100 images, instead of each image separately.
You can then loop over this array, which will be very fast as no further webtransactions are needed.
If the images you are fetching from the webservice are not dynamic in nature i.e. do not get changed/modified frequently, I would suggest to setup a scheduled process/cron job on your server which gets the images from the webservice and stores locally (in your server itself), so you can display images on the webpage from your server only and avoid third party server round trip every time webpage is served to the end users.
Both of the 2 option cannot resolve your problem, may be make it worse.
For option 1:
The process where cost most time is "get_from_web_service($item)", and the code is only made it be executed by another script( if the file "get_image.php" is executed at the same server).
For option 2:
It only make the "get-image-resource-request" being trigger by browser, but your server has also need to process the "get_from_web_service($item)".
One thing must be clear is that the problem is about the performance of get_from_web_service, the most straight proposal is to make it have a better performance. On the other hand, we can make it reduce the number of concurrent connections. I haven't thought this through, only have 2 suggestion:
Asynchronous: The user didn't browse your whole page, they only notice the page at the top. If your mentioned images does not all displayed at the top, you can use jquery.lazyload extension, it can make the image resource at invisible region do not request the server until they are visible.
CSS Sprites : An image sprite is a collection of images put into a single image. If images on your page does not change frequency, you can write some code to merge them daily.
Cache Image : You can cache your image at your server, or another server (better). And do some key->value works: key is about the $item, value is the resource directory(url).
I am not a native english speaker, hope I made it clear and helpful to you.
im not an expert, but im thinking everytime you echo, it takes time. getting 100 images shouldnt be a problem (solely)
Also. maybe get_from_web_service($item); should be able to take an array?
$counter = 1;
$urls = array();
foreach($items as $item)
{
$urls[$counter] = get_from_web_service($item);
$counter++;
}
// and then you can echo the information?
foreach($urls as $url)
{
//echo each or use a function to better do it
//echo '<img url="url_to_my_website/get_image?id='.$url->id.'" />'
}
get_image.php :
$url = get_from_web_service($item);
header("Content-Type: image/png");
echo file_get_contents($url);
at the end, it would be mighty nice if you can just call
get_from_web_service($itemArray); //intake the array and return images
Option 3:
cache the requests to the web service
Option one is the best option. I would also want to make sure that the images are cached on the server, so that multiple round trips are not required from the original web server for the same image.
If your interested, this is the core of the code that I use for caching images etc (note, that a few things, like reserving the same content back to the client etc is missing):
<?php
function error404() {
header("HTTP/1.0 404 Not Found");
echo "Page not found.";
exit;
}
function hexString($md5, $hashLevels=3) {
$hexString = substr($md5, 0, $hashLevels );
$folder = "";
while (strlen($hexString) > 0) {
$folder = "$hexString/$folder";
$hexString = substr($hexString, 0, -1);
}
if (!file_exists('cache/' . $folder))
mkdir('cache/' . $folder, 0777, true);
return 'cache/' . $folder . $md5;
}
if (!isset($_GET['img']))
error404();
getFile($_GET['img']);
function getFile($url) {
// true to enable caching, false to delete cache if already cached
$cache = true;
$defaults = array(
CURLOPT_HEADER => FALSE,
CURLOPT_RETURNTRANSFER => 1,
CURLOPT_FOLLOWLOCATION => 1,
CURLOPT_MAXCONNECTS => 15,
CURLOPT_CONNECTTIMEOUT => 30,
CURLOPT_TIMEOUT => 360,
CURLOPT_USERAGENT => 'Image Download'
);
$ch = curl_init();
curl_setopt_array($ch, $defaults);
curl_setopt($ch, CURLOPT_URL, $_GET['img']);
$key = hexString(sha1($url));
if ($cache && file_exists($key)) {
return file_get_contents($key);
} elseif (!$cache && file_exists($key)) {
unlink($key);
}
$data = curl_exec($this->_ch);
$info = curl_getinfo($this->_ch);
if ($cache === true && $info['http_code'] == 200 && strlen($data) > 20)
file_put_contents($key, $data);
elseif ($info['http_code'] != 200)
error404();
return $data;
}
$content = getURL($_GET['img']);
if ($content !== null or $content !== false) {
// Success!
header("Content-Type: image");
echo $content;
}
None of the two options will resolve server resources usage issue. Out of the two, though, I would recommend option 1. The second one will delay page loading, causing website speed to slow down, and reducing your SEO ratings.
Best option for you would be something like:
foreach($items as $item) {
echo '<img url="url_to_my_website/get_image.php?id='.$item->id.'" />'
}
Then where the magic happens is get_image.php:
if(file_exists('/path_to_local_storage/image_'.$id.'.png')) {
$url = '/path_to_images_webfolder/image_'.$id.'.png';
$img = file_get_contents($url);
} else {
$url = get_from_web_service($id);
$img = file_get_contents($url);
$imgname = end(explode('/', $url));
file_put_contents($imgname, $img);
}
header("Content-Type: image/png");
echo $img;
This was you will only run the request to web service once per image, and then store it on your local space. Next time the image is requested - you will serve it form your local space, skipping request to web service.
Of course, considering image IDs to be unique and persistent.
Probably not the best solution, but should work pretty well for you.
As we see that above you're including an URL to the web service provided image right in the <img> tag src attribute, one can safely assume that these URLs are not secret or confidential.
Knowing that above, the following snippet from the get_image.php will work with the least overhead possible:
$url = get_from_web_service($id);
header("Location: $url");
If you're getting a lot of subsequent requests to the same id from a given client, you can somewhat lessen number of requests by exploiting browser's internal cache.
header("Cache-Control: private, max-age=$seconds");
header("Expires: ".gmdate('r', time()+$seconds));
Else resort to server-side caching by means of Memcached, database, or plain files like so:
is_dir('cache') or mkdir('cache');
$cachedDataFile = "cache/$id";
$cacheExpiryDelay = 3600; // an hour
if (is_file($cachedDataFile) && filesize($cachedDataFile)
&& filemtime($cachedDataFile) + $cacheExpiryDelay > time()) {
$url = file_get_contents($cachedDataFile);
} else {
$url = get_from_web_service($id);
file_put_contents($cachedDataFile, $url, LOCK_EX);
}
header("Cache-Control: private, max-age=$cacheExpiryDelay");
header("Expires: ".gmdate('r', time() + $cacheExpiryDelay));
header("Location: $url");

Why is image request generating a 302?

I'm using PHP to generate the following image element:
<img id="uploaded-image" src="http://localhost/gonzo/plans/image/123/tablemap.png" />
This image URL is routed through my PHP MVC framework to the following function, which grabs the image from my db and prints it:
public function image($hexCode='',$fileName) {
if (!$this->validRequest('get')) return false;
Framework::loadModel('plan_model.php');
$plan = new PlanModel();
// Return image data from Blob field in db.
$image = $plan->getImage('123');
if ($image) {
header("Content-Type: image/png");
print $image;
die;
} else {
echo 'error';
}
}
The request generates a 302, with the wrong location and content-type headers:
The browser does not display the image where this image tag is on the page. But, when the image URL is typed directly into the address bar, the image is displayed.
Why would my server be generating a 302 when loading the image into an tag, but generating a 200 when the image URL is typed directly into the address bar? I'm running Apache on Windows.
The described behavior isn't possible at all - since the server doesn't know a bit about how an URL is embedded in a web-page.
Provide more details of the actual call of the PHP-script: Print environmental details - $_GET, $_POST and $_SERVER - to a log file.
It might be helpful to register a tick-function and trace each executed statement to a log-file.
Check your PHP sources.
It turns out that this was caused by a strange concurrency problem. My framework was still processing the first request (which generated the page containing the img element) while the browser requested the image.
In other words, when the browser requested the image, it was still receiving output from the first request to the script. This made things go wacky.
Output buffering didn't solve the problem, but possible solutions are:
Pause execution of the second (image request) script for a sufficient amount of time to let the first one complete.
Host the image serving script on a separate subdomain.

Displaying a Blob back as a Image in php without header("Content-type: image/jpg");

Im pulling the binary data out of my mySql database and want to display it as a image.
I do not want to make a separate page for it to display the image (this would involve a extra call to the databae among other things)
I simply want to be able to do
Pretty much but the $Image variable is in its longblob format and I need to convert it.
THanks in advance.
I know this is not a specific answer to your question, but consider that by removing that database call, you are dramatically increasing your server load, increasing the size of each page and slowing down the responsiveness of your site.
Consider any page stackoverflow. Most of it is dynamic, so the page cannot be cached. but the users' thumbnail is static and can be cached.
If you send the thumbnail as a data URI, you are doing the DB lookup and data transfer for every thumbnail on every page.
If you send it as a linked image, you incur a single DB lookup for when the image is first loaded, and from then on it will be cached (if you send the correct HTTP headers with it), making your server load lighter, and your site run faster!
I do not want to make a separate page for it to display the image
You can base64 encode your image data and include it directly into the markup as a data URI. In most cases, that's not a good idea though:
It's not supported by IE < 8
It (obviously) sizes up the HTML page massively.
It slows down rendering because the browser has to load the resource first before it can finish HTML rendering
Better build a separate script, and make that one extra call.
You could probably do this using Base64-encoded Data URIs.
I'm not sure if it's possible to do straight into a img-tag, but you can do it by setting a background-image for a div.
Basically you change the regular
.smurfette {
background: url(smurfette.png);
}
to
.smurfette {
background: url(data:image/png;base64,iVBORw0KGgo [...] P6VAAAAAElFTkSuQmCC);
}
Data URIs are supported in:
* Firefox 2+
* Safari – all versions
* Google Chrome – all versions
* Opera 7.2+
* Internet Explorer 8+
Info borrowed from Robert Nyman: http://robertnyman.com/2010/01/15/how-to-reduce-the-number-of-http-requests/
$_GET the result into a separate variable i.e. $myvar = $_GET['Id']; before you process the $imageResult line e.g.:
$myid = $_GET['Id'];
$ImageResult = "select player.Image from player where Id = '$myid'";
thanks for the answers, ive decided to go with a separate GetImage.php page but now cant seem to do the simplest of tasks
$ImageResult = "select player.Image from player where Id = " . $_GET['Id'];
$result = mysql_query($ImageResult) or die ("data recovery failed -3");
header("Content-type: image/jpeg");
echo mysql_result($result, 0);
But this returns just a broken link and cannot work out what I have missed out

Pull twitter profile image

Is there a quick way to pull twitter profile image in PHP or Javascript? I need to get the url of the FULL image (not avatar size). Thanks. Any code sample is good.
Twitter has had a nice simple URL.
https://api.twitter.com/1/users/profile_image/abraham
It has size options like "?size=bigger"
You can read more about it on Little known Twitter and TwitterAPI tips and tricks.
Twitter now has documentation up as GET users/profile_image/:screen_name.
Update: Support for this method has been removed from v1.1 of the API. Recommended practice going forward is GET /users/show and cache profile_image_url locally in your service/app.
function get_big_profile_image($username, $size = '') {
$api_call = 'http://twitter.com/users/show/'.$username.'.json';
$results = json_decode(file_get_contents($api_call));
return str_replace('_normal', $size, $results->profile_image_url);
}
get_big_profile_image('bobsaget', '_bigger') should return a large avatar:
http://a1.twimg.com/profile_images/330305510/n229938150541_9850_bigger.jpg
get_big_profile_image('bobsaget') should return an even larger image: http://a1.twimg.com/profile_images/330305510/n229938150541_9850.jpg
Apologies if this is something that's now known, but I didn't see it documented anywhere during my searches, including the official Twitter docs.
You can add the ?size=original as a parameter, which will return the original uploaded image for the user.
So:
http://api.twitter.com/1/users/profile_image/twitter.json?size=original
Previous answerers have provided the correct answer I wanted to link to original twitter api doc page so you'd know it is actually an official way of doing stuff:
You need to specify ?size=
bigger - 73px by 73px
normal - 48px by 48px
mini - 24px by 24px
http://api.twitter.com/1/users/profile_image/twitter.json?size=bigger
http://api.twitter.com/1/users/profile_image/twitter.json?size=normal
http://dev.twitter.com/doc/get/users/profile_image/:screen_name
So, it's not in the docs (http://dev.twitter.com/doc/get/users/profile_image/:screen_name), but it looks like after retrieving the image by specifying any of the three sizes (bigger, normal, mini), you can just remove the suffix before the file extension to get the original image. Hmm... is this safe to use?
For example, this query: api.twitter.com/1/users/profile_image/rrbrambley
Results in: a2.twimg.com/profile_images/931772958/deformed_cropped_headonly_normal.jpg
If I change this url by removing "_normal" then I get the original image: a2.twimg.com/profile_images/931772958/deformed_cropped_headonly.jpg
I know there are apps that use the original image. This must be the way?
When you get original image link, you can modify it to get bigger.
http://pbs.twimg.com/profile_images/34543543/image_name_normal.jpg
becomes
http://pbs.twimg.com/profile_images/34543543/image_name.jpg or image_name_bigger, ...
Source: https://dev.twitter.com/docs/user-profile-images-and-banners
I know this isn't the full code sample as requested (because there are several ways of doing this), but do you already have the URL for the avatar? I noticed that turning ".../eric.png" into ".../eric_bigger.png" resulted in the larger image. When "_bigger" already exists, removing it gave me the URL to the original image.
I tested this with several followers' profile images and, when the profile image was > 150px square, worked.
Twitter profile images urls:
Bigger: https://api.twitter.com/1/users/profile_image/puneetsindhwani/?size=bigger
Original: https://api.twitter.com/1/users/profile_image/puneetsindhwani/?size=original

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