Are ALL images 72dpi in web browsers? - html

I've used Fancybox (and similar) in the past to display images on websites. When I upload images to the server that are higher resolution than 72dpi, they usually take noticeably longer for Fancybox to load and display.
I was under the impression that all websites were displayed at 72dpi, and I threw images in under that general assumption. Can images be displayed at higher resolutions in a web browser? Is that why these images that I've used take longer to load? Or are they still displayed at 72dpi, but have to be scaled every time the page loads?
Thank you.

Images are shown at the resolution and dpi in which they are - for example; if i upload an 388dpi image to my site it will show at 388dpi at the same original resolution. The evidence behind this is that I am a web app developer. When first testing with one of my first apps we uploaded a full background image at 72dpi and the text wasnt very good so we made it higher dpi and same res and all worked perfectly!
Hope this helps!

Related

iOS rotates image when lower resolution selected (HTML5 Input file)

I am working on a web app that allows users to upload files to our CDN network, and then displays the images on the web app. However, I noticed something weird when uploading images through iOS (Safari) and possibly other browsers too.
When the highest resolution image is selected, the image is uploaded in its correct dimensions and shape.
However, when a lower resolution is selected, the uploaded image ends up being rotated on upload. I am not sure, if this happens with the CDN, or somewhere with the iOS file select feature, but its weird, since it works fine with the "Actual size" image.
You can see images below, to re-produce the error.
Pay attention the image shape, and file size. As "Actual size" the file size is 3.5MB!
Now, after we click on "Choose image size", following appears. I will choose "Medium".
After, you will see the file size is just 164KB. Reduction of -95.31%.
Then, pay attention to the shape, after the image is uploaded. You will see it is different rotation.
Does anyone have any clue as to why this happens? I am not sure if this has anything to do with the CDN I am using, because as I said before, when the "Actual size" image is selected, the uploaded image is perfectly fine. Only when size is changed through iOS "File selector" it changes rotation.
Also, another concern I have, is that these high resolution images are not necessary for my application. Sometimes we are talking +8MB for images, due to their high resolution and dimensions. Does anyone know if it's somehow possible to specify the image size for uploads on iOS/Android as default - so the user does not have to do anything? That would be ideal.
The images generated during choosing by iOS are missing the data for Orientation in the EXIF data for the image. That's why the image is correct when you upload the actual image, it seems oriented properly, but isn't right when it is a different size. You can check that by uploading the original and different sizes at https://exifinfo.org/. You'll see the different Orientation data in the EXIF section.
Since this is an iOS Safari specific feature, you can't rely on being able to choose multiple sizes of images that are being uploaded. A more reliable, cross-platform solution would be to resize the image yourself using a Canvas. This will however still probably require the user to upload the full size image, then you would have to process it on the canvas and upload it to your API.

Make iframe content non-responsive

So I'm making a grid with iframes in it. What I'm getting now is this:
As you can see, the website adjusts to the size of the iframe. What I want, is that the content will shrink to the size of the iframe, without using their responsive design. I don't have much experience with iframes, I hope there's someone here that can help me.
Thanks!
That cannot be done with Iframes -- The only real option you have is to take a screen shot of the website in a full size browser, and then serve a scaled image of the site.
This can either be done
when the user otherwise opens the website, and the scale down those images to the size you want
That is what google-chrome does for the short-cut page.
or server side, create a virtual browser and render the page server side, then take a screen shot of the virtual browser.
That is what some search engines have done in the past, where they offered a miniture view of the website for a search result before visiting (I however don't think any search engines currently offers this feature)

Why won't these images load on mobile? - HTML/CSS

On this page, the images look fine on desktop but are white/not found on mobile devices. I have no idea why this is happening. I'm just calling an img tag but it says its not found on mobile even though it is there
I have checked your files, #MrVimes is correct your should finish your html which will help validate better on slower devices.
However the problem is purely down to size of the image. Chrome Dev tools shows me that they are massive in size, Enable emulator and select iPhone 5 and see what happens. It is just taking a long time to download.
Try using Picturefil.js to serve smaller images or make them smaller in your software application.
This was the picture I got from Google Dev Tools (which is free and amazing):
Also I noticed that your need to change the way the images are handled in CSS, if you open dev tools:
Position:center
Is not valid, maybe set it to relative or static depending on how you want your page structure to look.
I also saw you may want to update your header with this css:
z-index: 99999;
This will make your header appear on top, as the z-index changes the layers of the html elements (much like the fillings in a sandwhich)
sorry my friend but this is false COMPRESSSING THE IMAGES TO 50KB the big images won't appear because your cache browser is full you have to empty your history/cookies/cache of the browser
IOS DEVICE SUPPORT 32 MEGAPIXEL SIZE OF IMAGE IN SAFARI
take a look here for maximum image size and resolution support Apple IOS developper
to delete your cache just go to "Setting=>Safari=>Cleare cache=>clear cache" and that's it
Note: Check the avaible space on your IOS DEVICE should be greater then 50MB
You have to Enjoy the technologie by let the images greater then 1.5mb and works in both of computers/devices

Serving identical double-sized images to retina display computers AND non-retina computers?

On my website, I have a 1300x200 image that I am forcing down to 650x100 using the simple width=650px parameter in the img tag. What happens when a retina Mac/iPhone/iPad user views my site. Will they see the full quality 1300x200 image, or will the quality artificially be reduced by half?
As far as whether or not this is efficient, it's just a 50k PNG. My site is otherwise mostly vectored with text/CSS. You could argue this is more efficient than messing with browser-agent detecting Javascript.
Ok folks, I went about answering it myself, and yes, if you use the width tag to half-size an img in HTML, the retina browser will display the full sized image.
I displayed the 1300x200 image half-sized using width on the top, and the plain 650x100 image on the bottom. Zoomed in using Safari on iOS 6.

choppy scrolling in IE7

I've built a website for someone, but according to him, scrolling is very very choppy on the website in IE7 on his computer. On my computer I don't have any problems with scrolling (in any browser), i've already tried some things, but according to him scrolling still is very choppy. So I was wondering if someone has some suggestions for me? I think the main problem is the full width background image, but i'm not entirely sure.
The website is:
www.casalagodilugano.nl
The website is in dutch, but for this question that doesn't have to matter
edit:
Tx for the helpful answers. In the end, it was indeed the background image which caused problems in IE7. By accident I found a way to work around this problem: I set the image as the background image, centered the image, and using css3 I made sure the was stretched the way it should.
I had a problem similar to this. It turned out to be because my computer was full and my performance suffered. Viewing the issue on my new machine (also had IE7) produced no choppy scrolling. I fear your client has the same problem, perhaps suggest it's his computer and not your website?
Edit:
Many things affect the processing on a website, I'd suggest it has to do with your background image. The sand has quite a "repeatable" texture so perhaps you should Photoshop it down so it's a much smaller image and just use 'background-repeat' in your CSS to achieve a similar effect. Your background image is also around 200% of what it displays on the website, I copied the URL of the image and viewed it by itself and it's HUGE! The emphasis here is on image file size, because IE is having trouble shifting the image down when you scroll. It's not a very good browser to be fair. I've also noticed that your large header image is larger in actual size, suggesting that the size is reduced by your code. Try reducing this image size to the size you want to display it
Edit pt 2
I've stumbled upon a script that for some reason waits 5 seconds before running and that is the Google maps API. I respect that you need this for the Routes page but if I were you, on any page where there is no map, remove any mention of the google maps api from the source code.
I have found that IE gets choppy when you have an <input> tag without a border or background specified ... very strange IE "bug" but i've fixed choppy scrolling on sites/pages by just adding a border to the <input> tags.