I've seen similar questions asked and the answers were not quite what I'm after. Since this question is slightly different, I'm asking again - Hopefully you'll agree this isn't a duplicate.
What I want to do: Generate an image showing the contents of my own website as seen by the user (actually, each specific user).
Why I want to do it: I've got some code that identifies places on the page where the user's mouse hovers for a significant length of time (ppl tend to move the mouse to areas of interest). I also record click locations. These are recorded as X/Y co-ords. relative to the top-left of the page
NB: This is only done for users who are doing usability testing.
I'd ideally like to be able to capture a screenshot and then use something server-side to overlay the mouse data on the image (hotspots, mouse path, etc.)
The problem I have is that page content is very dynamic (not so much during display but during server-side generation) - depending on the type of user, assigned roles, etc... whole boxes can be missing - and the rest of the layout readjusts accordingly - consequently there's no single "right" screenshot for a page.
Option 1 (which feels a little nasty): would be to walk the DOM and serialize it and send that back to the server. I'd then open up the appropriate browser and de-serialize the DOM. This should work but sounds difficult to automate. I suspect there'd also be some issues around relative URLs, etc.
Option 2: Once the page has finished loading, capture an image of the client area (I'd ideally like to capture the whole length of the page but suspect this will be even harder). Most pages don't require scrolling so this shouldn't be a major issue - something to improve for version 2. I'd then upload this image to the server via AJAX.
NB: I don't want to see anything outside the contents of my own page (chrome, address bar, anything)
I'd prefer to be able to do this without installing anything on the end-user pc (hence javascript). If the only possibility is a client-side app, we can do that but it will mean more hassle when getting random users to usability test (currently, we just email friends/family/guinea pigs a different URL)
One alternative solution would be to "record" the positions and dimensions of the main structural elements on the page:
(using jQuery)
var pageStructure = {};
$("#header, #navigation, #sidebar, #article, #ad, #footer").each(function() {
var elem = $(this);
var offset = elem.offset();
var width = elem.outerWidth();
var height = elem.outerHeight();
pageStructure[this.id] = [offset.left, offset.top, width, height];
});
Then you send the serialized pageStructure along with the mouse-data, and based on that data you can reconstruct the layout of the given page.
One thing we always talk about where I work is the value of ownership vs the cost required to make something from scratch. With the group I have, we could build just about anything...however, at a per-hour rate in the $100 range, it would need to be a pretty marketable tool or replace a very expensive product for it to be worth our time. So, when it comes to things like this that are already done, I'd consider looking elsewhere first. Think of what you could do with all that extra time....
A simple, quick google search found this: http://www.trymyui.com/ It's likely not perfect, but it points to the fact that solutions like this are out there and already working/tested. Or, you could download a script such as this heatmap Obviously, you'd need to add a bit to allow you to re-create what was on the screen while the map was created.
Good Luck.
IMO, it's not worth reinventing the wheel. Just buy an existing solution like ClickTale.
http://www.clicktale.com/
Related
Last year I tried to learn a bit React JS for making the project you can find here. I apologize for my rather vague / imprecise description below, but I'm by no means versed in this.
Basically, there is a single <svg> tag, which will contain a number of paths etc. as created by the user. The problem I have is that things become very slow the more paths are present. To my current understanding, this is due to the fact that the entire SVG DOM gets updated repeatedly upon user interactions that involve dragging the mouse or using the mouse wheel.
This holds true, particularly, for two user interactions:
a) Panning - all paths are being moved at the same time; I think one might circumvent this issue by taking a snapshot image first and moving that around instead. However, that's not a solution for the other user interaction, which is:
b) Expanding/collapsing paths - here, all paths are being modified in terms of coordinates of some of their points. That is, every path must be modified in a different way, but all of them must be modified at once, and this must happen repeatedly because it's a user interaction controlled with the mouse wheel where changes happen gradually and the user requires immediate visual feedback on these changes as they happen.
Particularly for b), I see no alternative that would involve a single transformation or something.
After extensive research last year, I came to the conclusion that choosing SVG to display and modify a lot of things dynamically on screen was a wrong decision in the first place, but I realized too late, so I gave up and have never touched it since. I'm pretty certain that there isn't any way to deal with the low performance that builds upon what I already have; I have no intention to start this project from scratch with a completely different approach. Also, the reason why I chose SVG was that it's easy to manipulate.
In summary, I'd basically like to get confirmation that there is no feasible way to rescue this project.
I am developing a website with React which has what we called "snippets", basically a modal window displaying some kind of media (audios, videos, slides, text quotations, pdfs). These media have "positions", as a page number, an image number, a playback position, or a scroll position. If she likes the user may store these snippets together with their positions in a "locker" and come back later to whatever is in there. Visually the locker will hold a "thumbnail" of the snippet representing the appearance of the snippet at the time of storing it. My question is how to go about making such a on-the-fly thumbnail. Two approaches come to my mind, however, if you have other ideas I am eager to hear them.
Component approach: Since I already have the component, I could reuse or rather clone it, scale it down, disable it for mouse interaction. Would React.cloneElement() be the way to go?
Advantage: Easy to do.
Disadvantage: Too many duplicates of potentially resource-heavy components may slow down website. Styling may become non-trivial as some embedded media (audio, video) bring their own potentially inaccessible styling with them.
Image generation approach: Since I only need an image, I could take a screenshot of the snippet area, scale it down and use it. Can this be done fully (from generation to usage) on the client side? Is there a good library which does the heavy-work for me?
Advantage: Resource-heavy only during the making of the thumbnail, resource-light in the locker. Accessible for any styling.
Disadvantage: Potentially difficult to do?
After some research I found a solution. Interestingly, it is a mixture of the two approaches I was able to think of. It is possible to access and rasterize the DOM elements which make up the snippets, draw them on a canvas and turn it into an image. The most popular library for this seems to be html2canvas, however, there are a number of others among which rasterizeHTML and html-to-image seem to stand out. Often wrappers for React exist, in the case of html2canvas, for example, use-react-screenshot.
So I'm building a portfolio and sales website for a painter (my wife) based on WooComerce (WordPress). This is a side project that I have plenty of time to finish. I want to build a live/moving photo wall, with perspective. The following photo will give you a (albeit, very rough) idea.
Basically, I want to start off with 16 images (the number is actually arbitrary), apply perspective to them and allow the visitor to click any of the pics and go to that images associated page. Now, after a given time, I want new photos to show up.
I'm not particularly concerned if I flip these pics, randomly, like tiles to introduce new ones OR if a column slides off and a new column is added (i.e. the adding of 17-20 in my picture). This is a semantic difference in the way I build this code and isn't part of my question (I don't think). All of the original pictures are going to be square and will be uploaded by the user, whom we assume is of novice/intermediate computer experience.
So my question is about the approach. Do I:
Make my wall script (likely using jQuery and HTML < map > and < area >) take care of the flipping and linking, but the perspective and scaling is done and cached on the backend.
Every image I upload to the server, for the photo wall, run it through a ImageMagick script that will transform (i.e. apply perspective of the largest size for the wall) and then scale it down for the other columns using a naming convention like: orignalthumnail_marilyn.png perspective0_marilyn.png perspective1_marilyn.png etc. (with the number for the different columns, relating to the scaled sizes). This is will be harder on bandwidth (maybe not, if compressed correctly) and easiest on the user's hardware (assuming non-mobile).
Use Javascript & CSS (and possibly HTML5) to do everything. I load the images into and use the CSS3 skewed/transformed < div >s, JS to flip/moves the tiles (I could do CSS I suppose). I feel that this option is the worst, as far as looks. This is because CSS clips horribly using the transform attribute (on my browser, FF 30) (I also made a quick demo at http://jsbin.com/febatohi/2/edit). Also, it requires the user's hardware to be able to handle all of the transforms, which is not always appreciated online. Maybe there is a way to handle this with a JS library I'm not aware of.
Use Flash. This is my least desirable option. It requires me to either not build this myself or pay someone else (pfft!) or that I acquire and learn Flash from Adobe (I said time wasn't an object, but patience can be). However, it can produce the best looking result, as I have seen things done similarly to this is Flash. It also is a middle ground of hardware and bandwidth, but to me the most time consuming and also limiting to those browsers and users who use Flash (though I feel this is only a small percentage of users).
Other suggestions?
This question already has answers here:
Preventing a visitor from saving an image from my site
(15 answers)
Closed 8 years ago.
I have a website where I display digital proofs for clients of professional photographers. I would like to include an option of 'zooming' into the full resolution version of the image, but it is absolutely imperative that it be practically impossible for the end user to reconstruct and save/print the image.
Obviously simply disabling right clicking is out, as the user could simply dig up the image in the cache. Breaking the image into tiles, then reconstructing them via javascript has merit; the user could still dig up the tiles and put them together in Photoshop, but is that practical for them? That's up for debate. I was also wandering today if the image couldn't be read, sent as a character string of pixel color values, and then constructed on the client side using an absolutely positioned element for each pixel.
But my potential solutions seem to be getting more and more ridiculously convoluted. And I'd like something that's been tested and shown to be scalable. I can't possibly be the first to deal with this problem. Is there something else out there that I don't know about? What is the standard, accepted way to do this?
As an aside, I am aware that I will want to make the image data unavailable to external http requests. I would plan to have ColdFusion read the image file on demand and stream it to the client.
Thanks!
No matter what you do, someone could always screen capture the page. Keep a watermark on the full resolution image.
With 100% reliability, no. For an image to be displayed, it has to be downloaded onto the client's browser, and therefore CAN be retrieved.
You can make it harder for them to extract the image through various techniques, but none of them make it impossible - if nothing else, they can always just make a screen capture:
slice/dice the image into multiple pices and use table-based layouts to make it appear as a single image
javascript right-click disablers
various cache headers to try and prevent client-side cacheing
CSS overlays to try and prevent right-click->save as on the image itself
display in a Flash/Java app
etc... etc...
None are 100% reliable, and are all trivial to bypass by a determined (and even slightly knowledgeable) user.
You can't, unless you sell specific hardware, even then people can put a camera in front screen and take pictures
You can water mark your images
You can actively sue who ever steals your pictures (that is in reference to how others solve this).
Nicholas,
As you pointed, there is no protection against Print Screen.
I would suggest you to implement the media protection of sites like Image Bank (http://www.gettyimages.com), but is mostly based in NOT displaying full resolution images and heavy watermarking ...
I don't think there is a practical solution to your problem (if any).
Good luck!
UPDATE: This question is outdated, please disregard
So.. my idea is to load a full manga/comics at once, with a progress bar included, and make sort of a stream, like:
My page loads the basic (HTML+CSS+JS) (of course)
As done, I start loading the imgs(the URLs are stored on JS var) from my server, one a time (or some faster way) so I can make a sort of progress bar.
ALTERNATIVE: Is there a way to load a compresses file with all imgs and uncompress at the browser?
ALTERNATIVE: I was also thinking of saving then as strings and then decode, they are mostly .jpg
The images don't have to show right away, i just need the callback when they are done.
XTML and HTML5 is acceptable
What is the fastest way to load a series of images for my website?
EDIT
Since #Oded comment.. the question is truly what is the best tech for loading images and the user don't have to wait everytime is turns the 'page'. Targeting a more similar experience like when you read comics in real life.
EDIT2
As some people helped me realize, I'm looking for a pre-loader on steroids
EDIT3
No css techs will do
If you split large images into smaller parts, they'll load faster on modern browsers due to pipelining.
ALTERNATIVE: Is there a way to load a compresses file with all imgs and uncompress at the browser?
Image formats are already compressed. You would gain nothing by stitching and trying to further compress them.
You can just stick the images together and use background-position to display different parts of them: this is called ‘spriting’. But spriting's mostly useful for smaller images, to cut down the number of HTTP requests to the server and somewhat reduce latency; for larger images like manga pages the benefit is not so large, possibly outweighed by the need to fetch one giant image all at once even if the user is only going to read the first few pages.
ALTERNATIVE: I was also thinking of saving then as strings and then decode
What would that achieve? Transferring as string would, in most cases, be considerably slower than raw binary. Then to get them from JavaScript strings into images you'd have to use data: URLs, which don't work in IE6-IE7, and are limited to how much data you can put in them. Again, this is meant primarily for small images.
I think all you really want is a bog-standard image preloader.
You could preload the images in javascript using:
var x = new Image();
x.src = "someurl";
This would work like the one you described as "saving the image in strings".
Spriting
Just have a look how facebook does it: http://b.static.ak.fbcdn.net/rsrc.php/z3JQK/hash/11cngjg0.png
One image that loads FASTER than series of small images. To display the icon you simply create a div with fixed dimensions, and move the background inside it. Your div works as a viewport for the big image. You use background-position to move to appropriate part of the image. Everything else is hidden.
Different domains
Something you probably didn't know - Internet Explorer has a limit of connections per server. You can read about it here: http://support.microsoft.com/?scid=kb;en-us;183110&x=17&y=11 (here are exact numbers).
What it means - if user is using IE7, he will be able to load ONLY 4 (or 2) files at the same time from your server regardless his internet connection speed.
To speed things up, you could create few subdomains: server1.mydomain.com, server2.mydomain.com, server3.mydomain.com etc - and then user can download many files a lot quicker, because you use different hosts to serve different files.
As done, I start loading the imgs(the
URLs are stored on JS var) from my
server, one a time (or some faster
way) so I can make a sort of progress
bar.
Your browser already downloads the HTML first, that's how it knows to load any JS/images you reference. You are trying to invent something that already exists.
Just make sure your manga is made up of lots of images of a known size, which you specify in your img tags. Most browsers have some sort of progress bar to show that it's loading resources for you. You're not going to make loading large images faster unless you improve either the speed at which your server serves them, or your user's internet connection, or you compress them to make your image files smaller (likely at the cost of image quality).
Note: JPG and PNG are already compressed.
You can try using a "CSS sprites" technique. Basically the idea is you use your favorite image editing program to stich all your images into a single image. It's faster to send this because you lose the per/file overhead in terms of encoding the image and sending the image. On the client side you use CSS to only select the portion of the total image that is used in any one place.
http://www.alistapart.com/articles/sprites/
http://www.fiftyfoureleven.com/weblog/web-development/css/css-sprites-images-optimization
AND/OR
You can use lazy loading to only load images when they come into view.
http://www.appelsiini.net/projects/lazyload
Image preloaders have been around for ages. You really do not need to load them all at once, you can do it on demand [when the person loads the next page, you can fetch the image after it]
My page loads the basic (HTML+CSS+JS) (of course)
As done, I start loading the imgs(the URLs are stored on JS var) from my
server, one a time (or some faster way) so I can make a sort of progress bar.
The images don't have to show right away, i just need the callback
when they are done.
If you want to load 10 images as fast as possible, place 10 <img> tags on the page, one for each image. Use Javascript to hide all the but the currently viewed image; add next/back links that use JS to hide the current image and show the next one. Many browser already have some form of progress bar, and by doing things with regular old HTML, it will function correctly.
You're trying to re-invent all this functionality with Javascript for no good reason. You're not going to do it better than the browser.
All that said, this is probably a bad idea. You might dump 15MB of comic pages into the browser window only to have the user leave after reading the first page. Rather than trying to pre-load all images, you should use JS to always keep the next page (or two) pre-loaded, not the entire thing.
Here's something you can try, which by happenstance I just coded up:
(function() {
var imgs = [ "image1.png", "image2.png", ... /* all your image names */ ],
index = 0,
img;
function loader() {
if (index >= imgs.length) return;
(img = new Image()).onload = loader;
setTimeout(function() { img.src = "/path/to/images/" + imgs[index++]; }, 1);
}
loader();
})();
Plop all your image names (or the ones you want to preload) into the array, and make sure this script starts up when your page(s) start loading. It'll work its way through the list of images, loading them, and then moving on to the next one when each image finishes. (The setTimeout call is to make sure that the "onload" handler doesn't get called while you're still inside a handler.)
You'd probably want to do this for lots of the "nuts and bolts" images for your whole site - in other words, each page would try to load images for everything. Once they're in the cache, of course, this won't take a significant amount of time. Alternatively, you could run this script only on a couple pages, like "login" screens and the main "home" page. Of course, if you've got a site like Flickr, then you probably wouldn't want to preload all your images :-)