While I was looking for some info, I came across this image on a forum which i didn't understood how it worked. Its a JPG image which actually tells you your ip address and your browser. I think that maybe it was made by modifying htacess and replacing PHP for JPG, and with PHP generating the image dynamically but I'm not sure about it.
Would this be the way that this works?
Here is the image i saw:
http://www.danasoft.com/sig/475388.jpg
Thanks
It is nothing but etching text on image. There are several options to do it. Using PHP see here and Java see here
yes this image is generating dynamically. It collects your info make a string and use some library to generate that image like in Captcha. php has its own library too for this purpose
Click here
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I would appreciate your thoughts on this method.
I have a page that uploads a pic given by user and displays it after saving it in a database now that's very simple so, I wanted users to be able to modify these images as they wish, hence I decided to add filters to these images using php. Now before these images are uploaded to the database I want the user to see a preview of what the image looked like after adding the filter.
The solution I came up was to send the image to php file using a form and AJAX using POST, do all necessary checks if file was safe. create a new image and add filter and then convert it to base 64 and send it back to browser and display it using a DATA URL
something like:
<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAAHElEQVQI12P4/8/w38GIAXDIBKE0DHxgljNBAAO9TXL0Y4OHwAAAABJRU5ErkJggg==" alt="Red dot">
Is this a good idea or there is something I should worry about?
Base-64 encoding adds about 33% overhead. For this reason, it is usually preferable to serve the image in binary form.
You can do this with a PHP script easily.
header('Content-Type: image/png');
echo $yourImageData;
Then in your HTML:
<img src="yourPHPScript.php?id=12345" />
hello we have a library for that actually, we make use of GD library to be able to achieve the correct image output that we would like to have, you can check more about our image library here.. by the way, our library does not only contain image library.. it has a bunch of useful libraries that you can actually use on your projects and we opensource it
http://eden.openovate.com/documentation/core/images
I've made some research and couldn't find the answer. Is it possible to detect an image resolution using an upload file field?
Right now, I can detect the size of an image in pixels...But I would need it to find the "inches" size.
And I also need to find out the resolution of the image.
Using Javascript would be the best...if possible, if not...PHP maybe?
Thanks!
You'll have to do this once it has been submitted. Check out the getimagesize function in PHP - http://php.net/manual/en/function.getimagesize.php
You will need a browser that supports the FileReader interface - read more at Is it possible to get info from a file on the client side without uploading the file?.
There are some javascript libraries reading such information like EXIF from the file:
JsJpegMeta
ImageInfo - although I'm not sure whether it gets its binary data by ajax from already uploaded files.
If you want to offer this functionality to user with browsers not supporting this, you will need to upload the file and do it serverside (with PHP).
I will create a dynamic page with content added and rearranged by JavaScript. Is it possible to create a jpg image of this content? - let's say, everything that is inside the container div will be generated to an image. If so, could anyone give me some good tips of this technique?
The traditional method is to run a "headless browser" on your server, "browse" to that url, and take a screenshot. It can be done to some accuracy on the client side in HTML5 browser, see this discussion:
Using HTML5/Canvas/JavaScript to take screenshots
This question may help:
Using HTML5/Canvas/JavaScript to take screenshots
and then this one:
convert canvas to jpeg image
The sequence of your algorithm would be something like:
create screenshot using canvas
convert the canvas screenshot to a
JPG file
Is there any way to programmatically create (client or server side (PHP)) a image from a specific DIV or a complete (web) page? I'm currently creating a web-site for free coupons and the idea is when the end-user clicks on the "Print" button, the app opens a new tab/window with all the selected coupons as a single image (JPG, PNG or etc..) in A4 format ready for printing. Each coupons has it's own data (Article name, price, description etc..) so I need it to be done programmatically over a coupon-template I designed.
I do not ask you to write code for me, just to suggest a solution I could use/develop. If not already exist, I will upload/publish it for free :)
Update: I did it with the PHP GD library :) Still not satisfied with the idea to use Images instead of PDF, because each printing results with different Coupon sizes (images) on different PC's. That's why PDF may would be a better solution. You can see/test it on demo.svikuponi.ba - Just select a few Coupons and click the PRINTAJ button above.
You cannot create image from div for sure but yes you can create dynamic images in php using its gd library.
Following links will help:
http://php.net/manual/en/function.imagecreate.php
http://phptutorial.info/learn/create_images/
Here is a great way for you to create images on the client side: http://smus.com/screen-capture-for-chrome-os
You can take this and create a web app that will work nicely on webkit (for other browsers - I'll look at JS polyfills).
Did anyone mention html2canvas and/or jsfeedback ?
It create a page screenshot completely in javascript, then you can send to the server via ajax..
Obviously, CSS support lack some things.
In php, there is many image related functions like imagettftext() in GD library
for details, check this out http://php.net/manual/en/book.image.php
if GD is not enough, you can try imagick as well
for the template, you can try creating a true color handle in php from your file(image) and add the text part or something else with all kinds of effects and bar codes etc.
but in your case, i would suggest dynamic PDF creation since it would better with formatting instead of plain image, the pdf lib :
http://www.fpdf.org/
you could easily have a background image of your token/voucher and overlay the text using some php variables.
i believe it is possible to create a unique bar-code with php imaging too.
It is possible to get a screenshot from a webpage, but this is quite a hassle. You need to start a webbrowser to render the page and get a screenshot from that.
You are probably better of by parsing some specification and feeding it to a couple of GD or Imagick functions. This is less versatile, but easier to manage.
I'm creating a web app that allows users to specify an image url to display an image along with their submission.
To avoid some potentially large images and odd sizes, i'd like to use PHP to limit/resize the image before it gets output to the browser (I know i could use max-width in CSS but this is unnecessary downloading)
Is this possible?
PHP has a library named GD. It's fairly easy to check the size of an image with the getimagesize() function.
You can find the complete code for it with 2 module/extensions: http://www.fliquidstudios.com/2009/05/07/resizing-images-in-php-with-gd-and-imagick/
a comparison of them can be found here: http://dreamfall.blogspot.com/2008/02/php-benchmarks-gd-vs-imagemagick.html which may be of use if you want optimize features.