I am working on a web app and am pretty new to web development.
Currently my program gets an and asks for user input relating to the photo.
For my project to be done I need to be able to do one of two things:
Select a random square in the photo and display only that portion. I want this portion of the image to change everytime the page is reloaded to show a different portion.
Detect a facial feature, like an eye or a mouth and show only that portion of the image.
Any free libraries or easy ways to implement either of these features?
Thank You!
For the first question, it's relatively easy. All you need is to set the image url as the background image of a square element, say, a <div>, and then use JS to randomly generate a x% and y% for the background-position: x% y% property:
$(document).ready(function() {
// Generate random x-y coordinates
var x = parseInt(100*Math.random(0,1)),
y = parseInt(100*Math.random(0,1));
// Set background-image and position
$('#img').css({
'background-image':'url('+$('#img').data('img-src')+')',
'background-position':x+'% '+y+'%'
});
});
For the HTML part, we take advantage of the HTML data- attribute:
<div id="img" data-img-src="/path/to/image"></div>
The CSS is also pretty straight forward:
#img {
width: 400px;
height: 400px;
}
You can see the fiddle here - http://jsfiddle.net/teddyrised/gabxj/
The second question - what have you tried? I did a quick search on Google and SO - Any library for face recognition in JavaScript?
Related
I am trying to embed a pdf within an iframe but when I set height to 100% it is really small.
Is there a way to make the height exactly one page?
my code
<iframe src="/wp-content/uploads/test.pdf#view=FitH" width="100%" height="100%"></iframe>
Try to add some CSS into your code as below:
<iframe src="/wp-content/uploads/test.pdf#view=FitH" style="width: 100%; height: 100vh"></iframe>
There are two parts to the question
Part 1
"when I set height="100%" the frame is too small
it will be 150px on whatever device since you cannot use % for frame height. The correct way is to set a frame to 100vh (viewport height as suggested by Baris Taskiran in their answer) but there are frame imbedding values that suggest say style as width: calc(100vw - 18px)!important; min-height: calc(100vh - 18px)!important ; can be preferable to avoid drag resizing issues.
see https://stackoverflow.com/a/74354395/10802527
Part 2
You cannot force a browser internal PDF view (it is after PDF download, or not, or download and view. Embed, iFrame or Object it makes no difference the PDF is out of your control and in the application/PDF) but you may suggest it attempt to FitV (fit the vertical) in the viewers downloaded frame.
However that can be meaningless for some PDF viewing plugins, if they are not Acrobat since those are Adobe Acrobat "fragments" and do not need to be supported by plugin extensions such as Chromes Foxit/Skia or Firefoxs PDF.js etc.
For more on the topic see https://stackoverflow.com/a/72265519/10802527 and https://stackoverflow.com/a/72106063/10802527
The question asked is why the middle FitV appears not to be working and since both the HTML and the PDF now belong to the user, they may edit or control view as they wish. This allows users to change font if they wish to inverted W&B Comic Sans or allow for different screen sizes/dpi etc. Both the files are 100% theirs.
The following answer does NOT work:
=====
This may not be practical for you, but this is how I guarantee that only one page of a pdf is displayed in an .
Give your a class--I use "x85x110" for 8.5" x 11" paper and use the following CSS:
iframe.x85x110 { height:calc(103% * (8.5 / 11)); }
The "103%" is a fudge factor that you can change to get exactly the height you want, i.e., to get just a hair of the blank space between one page and the next. The white-space on either side of the "*" and "/" is critical--calc won't work without it.
=====
This answer, however, DOES work:
=====
First the CSS:
iframe.x85x110 { width:80%; }
Second, the HTML:
<iframe class="x85x110" src="A Boy And His Dog/docs/Downunder Expansion - 8.5 x 11 - 10pt.pdf"></iframe>
Third, the javascript:
<script type="text/javascript" >
x85x110();
window.addEventListener('resize', x85x110);
function x85x110()
{
array_x85x110 = document.getElementsByClassName("x85x110");
for (count=0; count<array_x85x110.length; count++)
{
array_x85x110[count].style.height = Math.round(array_x85x110[count].offsetWidth * (11.0 / 8.5)) + "px";
} // for (count=0; count<array_x85x110.length; count++)
} // function x85x110()
Fourth, the explanation:
Give your <iframe> a class name, I used x85x110 because my documents are 8.5" x 11".
I use width:80% because I want the frame to be 80% of the width of the column width in which the .pdf and its containing <iframe> lives--this is NOT necessary.
The x85x110(); calls the function x85x110() when the page loads.
The window.addEventListener('resize', x85x110); calls the x85x110() function whenever the page is resized.
The array_x85x110 = document.getElementsByClassName("x85x110"); collects all of the <iframe> elements of the class x85x110 in an array named array_x85x110.
Then, for each element of array_x85x110, i.e., for each <iframe> of the class x85x110, we loop using the for (count=0; count<array_x85x110.length; count++) {} and set the height of the <iframe> to (11.0 /8.5) times the offsetWidth of the <iframe> with the the:
array_x85x110[count].style.height = Math.round(array_x85x110[count].offsetWidth * (11.0 / 8.5)) + "px";
Math.round() rounds the resizing of the <iframe>'s height to the nearest pixel.
The (11.0 / 8.5) divides the <iframe>'s .offsetWidth by 8.5 (the width of my pdf page in inches), which changes as the browser window is resized, and multiplies by 11 (the height of my pdf page in inches), to maintain the pdf's natural aspect ratio.
If for some bizarre reason you're using A4 paper, you European wierdo :-), the (11.0 / 8.5) would be (11.69 / 8.27), i.e., the height of a piece of A4 paper divided by its width.)
=====
You can see this CSS at work, for real now at my board game design page.
Sorry for the confusion.
You need to set the following settings in CSS (suitable for PDF page size):
width="594px"
height="580px"
I am trying to pull images from a database into an html table as a php variable:
<img src=img/$image&w=100&h=150>
the image does not show, but everything else in the table pertaining to the product shows
If I change the code adding a space after the variable:
<img src=img/$image &w=100&h=150>
The images show but they are very large.
How do I get $image to show at w=100 and h=150 within the table?
Thanks!!
OK I figured it out:
CODE:
<img src='img/$image' class='scale-down' style='width:100px;height:150px'>
CSS:
.scale-down {
object-fit: scale-down;
}
If the code below doesn't work for some reason, be sure you linked your CSS file.
CODE:
<img src='img/$image' class='scale-down'> <!-- Removed style attribute --!>
CSS:
.scale-down {
width:100px;
height:150px;
}
Another interesting point is if you want to you the object-fit then you can. Meaning you would have the images contained by the size of the elements you are putting them in. Therefore, you should be defining the width & height of the element that contains the images and then you can do as you did:
In this example I wrote td but I don't know what element contains your images so be sure to change it, if it is different.
td {
width:100px;
height:150px;
}
.scale-down {
object-fit: scale-down;
}
If your aim is to learn web-development then you should also be thinking about the client as kerbholz rightly points out:
Probably. Scaling down an image via CSS/style isn't a performant solution though, clients would still need to transfer for example a 1920x1080 image only to scale it down to 100x150. Anyway. – kerbholz
Please be aware that many questions about web development have already been answered here and on the web. Good luck!
The following are links to CSS, these websites have a lot more than just CSS.
MDN is really useful if you want to know more:
https://developer.mozilla.org/en-US/docs/Glossary/CSS
W3 is also useful but they don't always do as good of a job:
https://www.w3schools.com/w3css/
I hope there's someone out there that can help. I am trying to use jQuery Backstretch to apply a different background image for each specific page within Bootstrap/Wordpress. e.g:
Home - bg image a
About - bg image b
News - bg image c
and so on...
I've managed to use the standard Backstretch script to display a single image for all pages, but I am totally lost (even after searching) on how to apply the the above.
My code so far:
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<script src="http://myurl.co.uk/wp-content/themes/wpbootstra/bootstrap/js/jquery.backstretch.min.js"></script>
<script>
$.backstretch("http://myurl.co.uk/wp-content/themes/wpbootstrap/bootstrap/img/test_bg.jpeg");
</script>
I have used this in my footer.php.
Does anyone have a solution?
You could try:
<?php
if(is_page(42))
{
echo '<script>$.backstretch("http://myurl.co.uk/wp-content/themes/wpbootstrap/bootstrap/img/test_bg.jpeg");</script>';
}
else if(is_page(41))
{
echo '<script>$.backstretch("http://myurl.co.uk/wp-content/themes/wpbootstrap/bootstrap/img/test_bg_b.jpeg");</script>';
}
?>
The number 42, 41 being the id of the page. Sp text_bg_b.jpeg will only display on the About us page (assuming its id is 41).
I think there is no need for using backstretch: Just add this css styles inline to your body or main container:
background: url(PATHTOYOURIMAGE) center center no-repeat;
background-size: cover;
You should consider using a custom field for giving the path to your image. I think the easiest way is to install Advanced Custom Fields and to add a field called bg_image to every site with the image url in it. Then you can replace PATHTOYOURIMAGE with
<?php the_field('bg_image'); ?>
It is another way but I think you should give it a try.
I have a small problem with my PHP code and It would be very nice if someone could help me. I want to display an image when hovering over a link. This is the link with the PHP code that I have now:
<?php if ( has_post_thumbnail() ) {the_post_thumbnail();} else if ( has_post_video() ) {the_post_video_image();}?>
This code shows a image, but I want to execute this code when hovering over the link with the image:
<?php echo print_image_function(); ?>
The code also shows a image that belongs to a category. I don't want the initial image to disappear I simply want to show the second image on top off the first image when hovering over the first image.
I don't know if it is helpful but I use Wordpress and I am not a PHP expert. I even don't know if this is going to work. Thats why I am asking if somebody can help me with this.
Thanks in advance
THANKS EVERYONE
I want to thank everybody that took the time to read my post and helped me by giving their solution.
I didnt exspect so many answers in such a fast time. After spending a few hours trying it to get it to work with PHP, CSS and Javacript, I stumbled upon the following question on this website: Solution
It was exactly where I was looking for and with a few modifications to fit my needs, I got it to work. Sometimes things can be so easy while you are looking for the hard way. So for everyone that has the same problem: You can use one of the solutions that where given by the awesome people here or take a look at the link above.
Thanks again! :)
You can do this with CSS (if you so please and this fits with your overall architecture) - here is an example using the :hover condition and :after pseudo element.
html
<img src="http://www.gravatar.com/avatar/e5b801f3e9b405c4feb5a4461aff73c2?s=32&d=identicon&r=PG" />
css
.foo {
position: relative;
}
.foo:hover:after {
content: ' ';
background-image: url(http://www.gravatar.com/avatar/ca536e1d909e8d58cba0fdb55be0c6c5?s=32&d=identicon&r=PG);
position: absolute;
top: 10px;
left: 10px;
height: 32px;
width: 32px;
}
http://jsfiddle.net/rlemon/3kWhf/ demo here
Edit:
Always when using new or experimental CSS features reference a compatibility chart http://caniuse.com/ to ensure you are still in your supported browsers. For example, :after is only supported starting IE8.
You cannot randomly execute server side code on the client side.
Try using javascript AJAX requests instead.
PHP is a server-side language; you can't get PHP to execute after the page has loaded (because PHP completely finishes parsing before the page loads). If you want hover events, you need JS.
Firstly you don't need the elseif statement. An else will serve the same purpose, unless you intend to have blank tags where neither a thumbnail or a video image are present.
<a href="<?php the_permalink(); ?>">
<?php
if ( has_post_thumbnail() )
{
the_post_thumbnail();
}
else
{
the_post_video_image();
}
?>
</a>
You can't explicitly use PHP for client side functionality. You will need to use javascript or jquery to supply the on hover capability.
Jquery example:
$(function() {
$('a').hover(function() {
// Code to execute whenever the <a> is hovered over
// Example: Whenever THIS <a> tag is hovered over, display
// the hidden image that has a class of .rollover
$(this + ' .rollover').fadeIn(300);
}, function() {
// Execute this code when the mouse exits the hover area
// Example (inline with above example)
$(this + ' .rollover').fadeOut(300);
});
});
To have an image placed on top of another image you would need to make sure your CSS uses absolute positioning for the images with the image that is to overlay the other on hover is given a z-index value higher than the image to sit underneath it.
Hope this helps.
You'll need some JavaScript and/or CSS to make this work, since PHP is on the server side, not in the client browser.
I have a need for getting preview a url over mouse hover, my application is built on php , js and jquery. Although I have an idea of to get to my requirements but am a little confused with the right approach, i checked all the posted question on here but most of them refer to some third party tools or installables. Frnakly i do not want to use them and think i should try one on my own. Please can you guide me through on the best possible step as per you?
Thanks!
11-Jun-2012
Finally I managed to use Curl and get a preview of the site on a Div placed next to the Link on my site, well now the problem is of fitting the content in the Div ..is there a way that I can adjust the css of the extracted html page in such a way that all the content fits in the fixed height and width of the Div.scaledown option or something? that would scale everything down to the required proportion?
You can do this, in plain ol' CSS and HTML:
.mouseover {
position:absolute;
width:200px;
height:200px;
top:5px;
left:5px;
display:none;
}
.link {
position:relative;
}
.link:hover .mouseover {
display:block;
}
Then, in HTML:
<a href="#" class="link">Link
<div style="background:url('<URL HERE>')" class="mouseover"></div>
</a>
Ok, so you want to get a thumbnail of a webpage and show it on mouse over. To do that, you'll need to either use tools that generate thumbnails or write a PHP script yourself. Here are some tools:
websnapr
Website Thumbnail Generator - This one you can install on your own server
If you want to write your own, check out imagegrabwindow. Note that it requires a Windows server. I don't know if PHP has any other methods to do this. If you're not on a Windows server, you could write a bash script to open a browser and use a screenshot utility to take a screenshot and save it to a file for your website to pick up.
You'll also have to make sure to have some sort of cache so you're not doing this every time every user moves their mouse over a link.
You can use urlbox.io for this, here's an example preview thumbnail of this very URL:
https://api.urlbox.io/v1/ca482d7e-9417-4569-90fe-80f7c5e1c781/32040df25d7c57da28ef4da7ce461af00d852653/png?url=https%3A%2F%2Fstackoverflow.com%2Fquestions%2F10970647%2Fthumbnail-preview-of-a-url-using-php-and-javascript&thumb_width=400
You can see that the options passed into the Urlbox API are simply url, and thumb_width to set the desired width of the thumbnail in pixels, in this case I chose 400 pixels wide.
Now all you got to do is embed it in an <img> tag like so:
<img src="https://api.urlbox.io/v1/ca482d7e-9417-4569-90fe-80f7c5e1c781/32040df25d7c57da28ef4da7ce461af00d852653/png?url=https%3A%2F%2Fstackoverflow.com%2Fquestions%2F10970647%2Fthumbnail-preview-of-a-url-using-php-and-javascript&thumb_width=400"/>
You can use API to do this. For example ApiFlash has a free plan that you can use up to 100 screenshots per month.
Here is how it would look like with PHP:
<?php
$params = http_build_query(array(
"access_key" => "YOUR_ACCESS_KEY"
"url" => "https://example.com",
));
$image_data = file_get_contents("https://api.apiflash.com/v1/urltoimage?" . $params);
file_put_contents("screenshot_api_example.jpeg", $image_data);
?>
The API has a very good uptime because it's based on AWS Lambda.