Optimizing Image Size According to the Container, Not the Screen Size: A Guide

After exploring various resources on responsive images, I have come across a challenge that has me stumped. It seems like it should be simple, but I can't quite figure it out: How can I serve the appropriate image size based on container width rather than screen width?

For example, let's say I have a desktop screen that is 1980px wide, but a flex container that occupies 1/3 of the screen. In this case, the maximum image size required would only be 660px wide, which means it should display the 800w image. However, srcset typically relies on screen size, so even when displaying thumbnails, it will load the 1200w image. Is there a way to handle this dynamically? Can I still use flexbox and dynamic widths while serving the correct image size based on the container width instead of the screen width? Any assistance would be immensely appreciated, thank you!

<div class="flex justify-center w-1/3 mx-auto">
<img
  srcset="size-1.jpg 400w,
  size-2.jpg 800w,
  size-3.jpg 1200w,"
  sizes="(min-width: 1200px) 1200px, (min-width: 800px) 800px, 400px"
/></div>
htmlcssimageimage-processingresponsive

Answer №1

To determine the size of the image displayed, you can use mathematical calculations within the sizes attribute. Utilizing calc() allows for more intricate calculations, especially when dealing with margins between images or containers that are not full width.

Example without calc():

<div class="flex justify-center w-1/3 mx-auto">
  <img
    srcset="size-1.jpg 400w,
    size-2.jpg 800w,
    size-3.jpg 1200w"
    sizes="(max-width: 600px) 100vw, (max-width: 1200px) 50vw, 33.33vw"
  />
</div>

Example with calc():

<div class="flex justify-center w-1/3 mx-auto">
  <img
    srcset="size-1.jpg 400w,
    size-2.jpg 800w,
    size-3.jpg 1200w"
    sizes="(max-width: 600px) calc(100vw - 30px), (max-width: 1200px) calc(50vw - 30px), calc(33.33vw - 30px)"
  />
</div>

Answer №2

What is the purpose behind utilizing 3 different source files? Are they variations in size of the same image or do you aim to display entirely distinct images for each container size?

If your goal is simply to have the image adjust to fit its container, you can achieve this by setting a single source file and utilizing the CSS property width: 100%. By specifying the width of the image in percentages, it will automatically scale relative to the width of its parent element, which in this case is the <div>.

Aside from using % and px units for width, there are other options available. Look into Viewport Units for more information.

If your intention is to display three different images based on container size, then listing all three sources as currently done is necessary.

For further guidance, refer to this resource: Responsive Images In particular, consider this snippet:


    <img
      sizes="(min-width: 400px) 80vw, 100vw"
      srcset="examples/images/small.jpg 375w,
              examples/images/big.jpg 1500w"
      alt="…"
    >

The provided markup equips the browser with essential information to determine > the most suitable image. The browser evaluates both its viewport size and pixel density.

For instance, if the browser viewport measures 320px wide at a 1x display, and intends to display the image at 100vw, it must choose among the available images. A calculation ensues.

Image #1 (375 pixels) / Available 320 pixels = 1.17 Image #2 (1500 pixels) / Available 320 pixels = 4.69

With a 1x display, 1.17 is closer to 1, so the 375w image prevails. The browser aims to avoid distortion, hence 1.3 would surpass 0.99, to my understanding.

* To clarify, pixels technically represent an angle measurement akin to degrees and radians, based on assumptions regarding the distance between the screen and viewer.

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

Using PHP to access HTML content from a page that demands authentication

I need help developing a PHP script that can scrape data from an HTML page. Right now, it works perfectly with pages that don't require authentication. However, I'm struggling to figure out how to extract content from a page that requires users t ...

phphtml

Having trouble with imagecopyresampled function, unsure of the reason behind its malfunction

I am currently trying to use imagecopyresampled to crop a specific section of an image, in order to prevent users from uploading photos larger than the intended size on my website. However, I am facing an issue where imagecopyresampled seems to be resizing ...

phpcssimagejpegphp-gd

What is the best way to acquire an ID that is generated dynamically?

Being new to javascript and ajax, I am facing a challenge. I have a while loop with 2 buttons, both of which seem to function correctly, except for one small issue... The product-id is only being passed for the first or last element in the loop. How can I ...

javascriptphpjqueryhtmlajax

Encountering an unspecified variable in Sass

I am a beginner in the world of sass and I am trying to incorporate a variable from a file named "_designs.scss" into another file called "_component.scss". Despite my efforts, I keep encountering an "Undefined variable: $grey-light-2" error. I have exhaus ...

csssass

Is there a way to use javascript to ensure that CSS variables stick even when overwritten by onclick events?

I have successfully implemented a method to change CSS variables using advice found here. However, I am running into an issue where the changes do not persist. After clicking on a navigation link, the styles momentarily switch to the new values but quickly ...

javascriptjqueryhtmlcss

Show the precise selection from one dropdown menu based on the chosen value in another dropdown menu

How can I retrieve the scheduleID value from a specific MovieID value within a comboBox? Movie Selection Box: <?php $query = "select * from ref_movies ORDER BY MovieID"; $result = mysql_query($query) or die (mysql_error()); echo '<s ...

phphtmlmysql

What steps can I take to prevent BeautifulSoup from interpreting commas as tab characters?

My recent project involved creating a web scraping code to extract information from a local news website. However, I have encountered two issues with the current code. One problem is that when the code retrieves paragraph data and saves it to a CSV file ...

pythonhtmlcsvweb-scrapingbeautifulsoup

Problem with updating an Html.TextBoxFor based on the value of another one

I have been trying to implement a basic jQuery functionality that involves changing the text in one textbox to be half of the numeric value entered in another textbox. Below is the script I am using: <script> $(document).ready(function () { $(& ...

javascriptjqueryasp.nethtmlvisual-studio-2013

Calculating the dimensions of a CSS element based on its content

Is there a way to achieve this using only CSS, without needing JavaScript? I am working on a project with a lot of relative and absolute positions, where elements must be centered dynamically without specifying static widths. While I have managed to minimi ...

css

Using a combination of radio buttons and JavaScript to adjust the color of a div element

Currently, I am experimenting with radio buttons to modify the background color of my div tag. My goal is to incorporate more than one condition. For example, if button A and button B are both clicked, then change the color to green. This is what I have im ...

javascripthtmlradio-button

Transform HTML invoices into emails

I am currently working on developing an ERP system. I have an HTML invoice that needs to be converted into a PDF and sent via email. My question is regarding how to construct the invoice using jQuery & AJAX, convert it into a PDF format, and then send it ...

jqueryhtmlasp.netajaxcss

Retrieve information from internet sources

I'm attempting to extract the initial paragraph from Wikipedia by utilizing only JavaScript. Essentially, my goal is to: document.getElementsByTagName("P")[0] However, this content is not present on my own website; instead, I aim to retrieve a speci ...

javascripthtmlwikipedia-api

Angular causes HTML Dropdown to vanish once a null value is assigned

In my scenario, I have two variables named power and mainPower. Both of these variables essentially represent the same concept, with mainPower storing an ID of type Long in the backend, while power contains all attributes of this data transfer object. The ...

htmlangulartypescript

Enable scrolling for a div positioned beneath another div

I am working with an iPad frame and trying to implement a feature where a larger image scrolls behind it as the user scrolls down the page. Although my CSS is more complex than the example provided in this link, I am struggling to get even that basic funct ...

htmlcss

Change the border color of a form field in a material design if the user interacts with the

Is there a way to change the border color of a material form field in Angular when it is touched, focused, or active? I attempted to modify the color by overriding material css-class and also tried creating my own css class, but neither method had any ef ...

cssangular-material

Only implement $(document).on(...) for every JQuery request

As someone new to Jquery, I'm facing challenges in grasping its functionality. Specifically, my struggle lies in setting up an event listener on an i element with the class of .dataPickerIcon, which should respond to a click by inserting more HTML usi ...

javascriptjqueryhtml

Sorting through a table based on the name of the element

I am currently working on filtering an HTML table using a search form. It's working great, but I'm facing an issue where the filtered elements are trying to fill the entire width of the table instead of maintaining their original width (which is ...

javascripthtmlcssfilterwidth

The art of jQuery: Effortlessly animate the deletion of a CSS property

When using jQuery, I often "collapse" certain DOM elements by decreasing their width to 0px and fading them out. Here is an example: $(".slideoutmenu").animate({ width: 0, opacity: 0}, function() { $(this).hide(); }); The widths of these elements can var ...

jquerycss

Enhance your textbox with more detailed descriptions than just displaying NaN

I am working on a form that includes select boxes. If a user selects an option from "Convert From" and another option from "Convert To" but does not enter a number in the input field, instead of displaying NaN in the result text box, I would like to show ...

javascriptjquerycss

Problems with Bootstrap affix scrolling in Internet Explorer and Firefox

I'm encountering an issue with the sidebar on my website. I've implemented Bootstrap affix to keep it fixed until the end of the page, where it should move up along with the rest of the content at a specific point... Everything seems to be worki ...

javascriptjquerycsstwitter-bootstrapaffix