I have an image manager that shows a fixed sized grid of images. The thumbnails are relatively small already so I can't really make them smaller. I implemented lazy loading and using a debounce function to check if the images on in the visible region. This increased the speed of launching my image manager. However, if I scroll while the new batch of images are being loaded, the scrolling becomes very slow. Is there anyway around this or to further optimize loading images?
EDIT:
Is there a way to prevent scrolling while a new batch of images are coming in? Kind of like how Youtube just keeps bouncing when we try to scroll to see more comments while they are still being loaded?
Try not to load all the images at once (which I guess you've implemented with Lazy loading), I'm aware that the users online have a high tendency to scroll fast.
I would suggest, few things here:
First
Implementing the Lazy loading in a correct way is essential. here is a list of few best techniques, make sure which works best for you.
You've mentioned, that the thumbnails are relatively small, however I assume only specifying smaller dimensions is not sufficient, I hope you have covered this ground, Else maintain two folder one for Actual images and another for Thumbnails on your hosting server.
Even though we take utmost care, users upload tons of heavy images on our server, if that is the case, you need to resize the images on client end and then upload on the server, one copy in Actual images and another for Thumbnails
If you are talking about product images, keep the PNGs, Why, because they are far better then BMPs and JPGs. Also you can compress them with online tools like https://tinypng.com/ OR with softwares like https://pngquant.org/
Hope this helps resolve your issue, coz it did to resolve mine.
--N Baua
It turns out the slow scrolling was due to me calling getBoundingClientRect() to find new visible images while there were some images still being loaded. That caused a reflow which bogged everything down.
I changed it to load images in batches so that getBoundingClientRect() isnt called when there are images being loaded.
Related
I am trying to write a chrome plugin so I can use some websites that includes a lot of images I dont care about that are problematic to load seeing as my internet connection is poor.
As such, is it possible to stop loading images but just load white boxes instead, with the exact same size, attributed links etc.? I am a bit unsure where to even start on this, as I tried to just .display = None, but that does not help me loading the website when my connection is bad.
Reason why I want to load something is because if all the images etc just disappear the website layout basically goes down the drain and I can't scroll around on it.
In my HTML5 mobile app, I am retrieving 10 images at a time from imgur (the user clicks a button to get more images). When the images are retrieved, I apply some formatting via CSS (mostly to the height and width so that it properly fits the dimensions of an iPhone).
My guess is that one of the reasons why it’s taking so long is because I’m applying formatting to the images once they’re retrieved and then showing these images. Would I be better off saving the images in the state they should be displayed with the right dimensions so I don’t have to apply any CSS to them? Would this help in getting the images to load faster?
Thanks!
According to this post, you should probably be grabbing only six at a time.
Also, open your browser's debugger, go to the NETOWRK tab and watch how long things are actually taking.
Are the images that you are loading actually bigger than the display size? If so, it will load slower not because of the CSS application, but because you are loading unnecessarily big images. You should always re-size the images that you use to the displaying size. You can also change the format and/or compression of the images to make it smaller, thus loading faster.
I have an image of a vine of leaves I'd like to load slowly from left to right after a delay (after the site fully loads) to underline and emphasize a slogan of website I'm working on. I don't want to animate the image, just make it seem as though it is growing by loading it slowly.
Is there a CSS solution or would it be easier to use Jquery?
Thanks so much in advance for any help!
I don't believe there is a CSS solution to your query. In photoshop you can save a jpeg or png as progressive (interlaced) so that it downloads progressively but on anything but the slowest link a regular size file will appear to load quickly.
I would have thought your easiest option was an animated gif - the opacity and apparent size could be tightly controlled and you can set it only to run once per visit. You could bind the image to the jQuery(document).ready() callback for the "after the site fully loads" part of your request.
I've been given a design for a commercial affiliate-related website where the homepage has 2500+ images on it. Two directions I'm thinking about to ease the loading of the images is to utilize a lazy image loading script.
I've been messing with the jQuery JAIL (Async Image Loader) script. I have it set so that it loads all the visible images when the page loads. Then after a couple seconds it begins downloading all the rest of the images on the page that are below the fold. This is typically like 2400+ images.
The problem is that when the browser is told to download 2400 images it basically freezes up, or at least freezes up the scrollbar until it's done.
Are there any jQuery image loading scripts that are similar to the JAIL but that allow for some type of throttling? Anything really to help from freezing up the page.
I'm also looking into css sprites but for various technical reasons and time constraints it might not be feasible.
Use this jQuery plugin. Example here
It delays loading of images in long web pages. Images outside of viewport (visible part of web page) wont be loaded before user scrolls to them.
Using Lazy Load on long web pages containing many large images makes the page load faster. Browser will be in ready state after loading visible images. In some cases it can also help to reduce server load.
If the images are small, you might consider combining them into fewer large images and loading them all at once, displaying them all as <div> elements with their background image set. Example:
http://jsfiddle.net/XXRwD/
My CMS project has a stylish web 2.0 login screen that fades over the screen using javascript. How come that even though I have made 120% sure that images are preloaded (I used the resource monitor in development tools) they still take a second to show up when my login screen appears. It completely destroys the fanciness! Take a look:
http://www.dahwan.info/Melior (link broken)
When you click login, the screen is supposed to fade to dark using a 75% alpha 1px png image. Even though the image is preloaded, it doesn't show up until after the animation is done. However, if you click cancel and log in again, the animation flows smoothly and perfectly.
Can anyone think of a solution to this problem? I'm having it with the rest of my CMS' GUI as well. It's like there was no image preloading what so ever.
Thanks for answers
EDIT: Ah yes, I'm currently developing this CMS for Google Chrome 5.0.375.99, adding multi browser compatibility later. Sorry for leaving that out
I have come up with a workaround to my problem. I have now tested this in three browsers on two different computers with perfect results. In short, in my image preloading function in javascript, i added each of the images into the DOM in an invisible Div tag.
$('#img_preload').append($('<img />').attr('src', img.src));
The images now being added to the Dom at page load, and according to my theory resting in the memory of my low-end computers, they appears instantly when my CMS needs them.
Thanks for your comments :)
A useful information about this problem:
The Codemonkey solution works because, by putting the images in a hidden div, the browser have to keep those images in memory and ready for a possible change of div's visibility. If the user needs to change de visibility of div from hidden to block, it has to be done instantly. This is why just load all images into an array doesn't work properly.
You could also just preload them into an array. Your problem might be caused by what is known as "garbage collection". This is where the browser looks for objects that are consuming memory which no longer have an instance on the screen and are not being referenced by anything else in memory.
If you preload images into your web age, they should be loaded into the cache, though. So, they should still re-appear when referenced again. However, images can also disappear if the cache expiration is not set for a long enough length of time for these types of files.
Your problem could also be browser-specific.... I have found that it is always best to create an "anchor" for pre-loaded content by placing them into an image array and then using the array to call up the images when needed instead of the image URL(URI).
Here is a quick-and-dirty article that covers this topic.
https://web.archive.org/web/1/http://articles.techrepublic%2ecom%2ecom/5100-10878_11-5214317.html
The UI thread can only manage one task at a time -- it will either execute javascript or update the UI. If there is a lot of javascript parsing/executing before the code that preloads the image, that might be causing the delay.
Another suggestion is to disable clickability on the login link until after the image has been detected on the page.
To do so is fairly straightforward:
function disableBtn(el){
var btn = document.getElementById(el);
var btnId = btn.id;
btn.disabled = true;
}
To re-enable, set btn.disabled = false (after detecting that your image has been added to the DOM).