i have a question to ask you. So I have on my webpage a showcase that has some images that keep playing. I used JCarousel to build it. The thing is that when i first enter on the page i can't see the image or I see only a part of it. I suspect that this is because the site a few seconds while it loads all the images it has. My question is: how can I make certain images be the first ones to be loaded? Or how can I prioritise the way the images load on the page? By the way I'm doing this in html,php using javascript and ajax and the images are taken from a database.
Thank you very much!
If you Base64 encode them, you can put them in the CSS, or HTML. It will really increase the side of a page, so perhaps encode a low resolution picture, and then replace it with highres when it loads. That is, a preview image.
Try this tool/guide.
Related
I Googled a lot but no sufficient ans was found.
I need to place an image (900 X 5200 px) in one of my pages. As the image is sensitive, I need to prevent users from copying the image. I have an idea that can do this:
I will divide the image into pieces. Then the image grid will be loaded into some divs. So user won't be able to save the image. Or he/she will save only 1 square cm part of the whole image.
But this plan will not work if some small parts of the grid fails to load. So, I want to do another thing. I want to load the full image then cut the image into parts. Then show the parts altogether in divs.
This requires javascript. But I am confused how to start and need your help.
Now you know the matter, if you have better idea please share.
Thanks in advance.
The trick is simple. Create a div with the background being the image you want to display. Layer a div with a transparent image over it. When user goes to save the image, they get a blank. Program your server to not return "direct" requests for the image (so some clever chap can't just look at the css and retrieve the URL to the image).
Granted the image will still be in their cache but so would the sliced image so it won't make it impossible just more difficult for a determined person to retrieve the picture.
TL;DR Don't over engineer a solution, print screen will get around anything you do.
You are not going to be able to prevent people from copying this image. Plain and simple. Regardless of your best efforts, a simple PRT SCRN and paste into Paint will be enough.
Your best bet will be to not over engineer this and simply place a watermark and copyright notice on the page. Other options can include placing a transparent <div> over the top of the image so it cannot be right-click'ed and saved, but it still will not prevent the image from being stored in the user's cache. Or stop them from using developer tools or Firebug to find the source image.
You can do this with:
http://www.pixastic.com/lib/docs/actions/crop/
Yet you need to develop your logic around that library.
I have made example, you can see it on this link:
http://simplestudio.rs/yard/crop_img/
Basically you can get URL to your image via php and using my code or code similar to it crop your image into pieces and display them on canvas.
This way image is not accessible via browser or inspect element or what so ever. User can save the pieces individually but you can configure my code for piece to be 5px, I set it to 20x20px.
* test saving image piece by doing right click anywhere on image and do a "Save image as.." option.
Also you need to think of way how to hide src to image provided by php, if you need help on that I can help you.
My page will have a lot of images, which will take a lot of time to load and will make it very slow, so my question is
how to make the page to download and display only the pictures that are being shown in front of you, exactly the same as performing image search with google, whenever you scroll it will keep downloading and displaying the focused images.
Thanks all.
Image lazy loading
eg Lazy Load Plugin for jQuery (http://www.appelsiini.net/projects/lazyload)
Demo: http://speckyboy.com/demo/lazy/index.html
Use ajax, you can easily detect the view port by javascript and the images dimensions, so when scrolling, all you have is to send request to populate more rows of the view, this could be tables or div.
You can't do something like that in PHP.
It has be done in JQuery.
There is a plugin that does what you need, called Lazy Load.
Take a look on this site: http://www.appelsiini.net/projects/lazyload
I'm displaying pieces of an image in a large grid created from divs. I'm using the background-image and background-position to display portions of the image. The problem I'm running in to is that a user can simply open up firebug and see the entire image (which defeats the purpose of the game).
I've attempted to mask the path using a php script as the URL but if the user navigates to the php file, they can still see the image. It would appear that anything I do with the CSS is entirely client side so denying everything outside the localhost in my .htaccess won't work.
Any suggestions?
The over arching goal is to have an automated way to split and display pieces of the image into a grid.
If you deliver the whole image to the browser, the browser holds the image and has every right to show it to a user. I don't think you can prevent the browser from showing it. I'm afraid you will have to deliver the image in pieces, or perhaps write your whole game using <canvas> and play around with images as pixel data. :)
This question is a bit open at the moment as I'm not sure the idea is even possible.
So far I've loaded an image from a url, and then used jQuery UI draggable feature to allow the user to drag html text (which has been replaced using cufon font replacement) over the top of the image.
The major step (which is what my question relates to) is being able to take the image and text layered over the top of the image, and save the result, either to the server, or potentially offer the option to save the altered image to the user's HD, or what would also be useful is to upload to facebook using the facebook API, but this is something I know is possible.
It all hangs on whether it's even possible to achieve the first step, which is to save the image and layered text as a combined image?
I wonder if there is a PHP/jQuery solution that would allow me to do this?
My suggestion would be to have an internal URL that outputs the final image using jQuery and PHP, then take a screenshot using webkit2png of that page. You should know the dimensions etc., so you'll be able to crop down the resulting screenshot to just the region you're looking for.
I am working with php. I have images kept in order. When i do query the images comes in order but when they load they does not load in order. The small images load first and then big images. For example I have 5 images. These images should be loaded in order(1,2,3,4,5). But here its not happening. Image 4 loads first, then 2, 1 and so on. So what can i do for this problem? Hope to get solution.
Thanks in advance.
If you are speaking about the order images are displayed by a web browser, you do not have much control over that, as long as you have several <img> tag on your page :
the browser will request the images from the server in the order it wants (most probably, the first <img> tag encountered will be the first image requested)
each image takes some time to download ; and each image is displayed when it's downloaded ; considering small images should be downloaded faster, small images should be displayed first... depending on the order they were requested -- see previous point.
In the end, if you want absolute control on the order the images are displayed, your initial HTML should probably not contain all the <img> tags: a solution would be to add those, in the right order, when the previous image is downloaded.
This can probably be done with some JavaScript code, to detect when an image is loaded (event "load") ; and when an image is loaded, just add a new <img> tag to the page, for the next one; and so on.
But I wouldn't go with such an idea: it won't work if JS is disabled, your images will not be seen by search engines.
You can control everything on your web server, but nothing on network or browser sides.
A possible solution is to build a single image containing your five images and display each relevant portion to its dedicated position.
Have you tried preloading them with a JavaScript library?
Not sure how you would implement this in PHP, but in the past I have usually had the a 'order' field for each image, then the images were added dynamically according to the 'order' field.
As you should have guessed, image is loaded according to their sizes. Ofcourse, the smaller ones will load before the bigger ones. And yeah, as eyze said, wat about you preload them with a javascript preloader and display them in the right order?