Enhancing Your Next.js App with the Image Component

The Next.js Image component is a versatile tool aimed at optimizing image rendering and boosting website performance.

In this article, we will delve into the reasons why developers should incorporate the Next.js Image component, its numerous advantages, and the necessary adjustments to the next.config.mjs file for incorporating image resources from external sites such as images.unsplash.com.

Why Use the Next.js Image Component?

Image Optimization
The Next.js Image component automatically optimizes images, reducing their file sizes without sacrificing quality. This optimization process occurs during the build phase, resulting in quicker load times and an enhanced user experience.

Lazy Loading
One of the standout features of the Next.js Image component is its default lazy loading capability. Images are only loaded as they enter the viewport, which significantly cuts down the initial page load time and boosts overall performance.

Responsive Images
The component supports responsive image loading by creating multiple sizes of an image and serving the most suitable size based on the user’s device and screen resolution. This ensures that each user receives the best possible image for their specific viewport.

SEO Benefits
Optimized images contribute to improved SEO by speeding up page load times and reducing bandwidth consumption. Search engines tend to favor faster websites, which can lead to higher rankings.

Developer Experience
The Next.js Image component extends the standard HTML <img> element with features like automatic optimization, lazy loading, and responsive images. This makes it simpler for developers to handle images efficiently.

Advantages of the Next.js Image Component

Reduced Bandwidth Usage
By optimizing images and delivering them in modern formats like WebP, the Next.js Image component decreases bandwidth usage, benefiting both users and servers.

Improved Page Load Times
Optimized and lazy-loaded images lead to faster page load times, which enhances user experience and lowers bounce rates.

Enhanced SEO
As previously mentioned, quicker page load times and optimized images contribute to better SEO, helping websites achieve higher search engine rankings.

Streamlined Development
The component’s built-in features simplify the development process, allowing developers to concentrate on other critical aspects of their projects.

Nextjs Image component attributes

This Next.js Image component has several attributes that define its appearance and behavior:

1. src: This attribute specifies the source URL of the image to be displayed.
2. alt: The alt attribute provides alternative text for the image, which is displayed if the image cannot be loaded or for accessibility purposes, such as screen readers.
3. fill: Setting the fill attribute to true makes the image fill its parent container. This is useful for responsive design, as the image will automatically resize to fit the available space.
4. className: The className attribute is used to apply CSS classes to the image element. In this case, the “rounded-t” class is applied, which likely adds rounded corners to the top of the image.
5. sizes: The sizes attribute defines the size of the image relative to the viewport. In this case, it is set to “100vw”, which means the image will take up 100% of the viewport’s width.
6. style: The style attribute is used to apply inline styles to the image element. Here, the objectFit property is set to “cover”, which ensures the image covers the entire area of its parent container while maintaining its aspect ratio. This may result in some parts of the image being cropped if the container’s aspect ratio differs from the image’s aspect ratio.

Note: When using fill with the Next.js Image component, the parent element must have a position: relative CSS property. This is necessary for the proper rendering of the image element in the layout mode, as it ensures the image is correctly positioned and sized within its parent container.

<div className="relative h-96 bg-center ">
   <Image src={...} alt={name} fill={true} className="rounded-t" sizes="100vw" style={{ objectFit: 'cover' }}/>
</div>

Here’s a table summarizing the different options for objectFit:

Configuring next.config.mjs for External Image Resources

Adding External Image Domains
To leverage images from external sources such as images.unsplash.com, you need to configure the next.config.mjs file. This allows Next.js to optimize images from these external domains.

Edit next.config.mjs: Add the external domains to the images configuration key.

module.exports = {
images: {
   domains: ['images.unsplash.com'],
   },
};

This configuration ensures that images from images.unsplash.com can be optimized by Next.js.

Custom Image Loaders
If you prefer utilizing a cloud provider for image optimization, you can configure a custom image loader in next.config.mjs.

module.exports = {
   images: {
      loader: 'custom',
      loaderFile: './my/image/loader.js',
   },
};

This setup allows you to define a custom loader function for generating image URLs. Here is an example of the next.config.mjs file

/** @type {import('next').NextConfig} */
const nextConfig = {
  images: {
    deviceSizes: [640, 750, 828, 1080, 1200, 1920, 2048, 3840],
    remotePatterns: [
      {
        protocol: 'https',
        hostname: 'plus.unsplash.com',
      },
      {
        protocol: "https",
        hostname: "pxrfpljhxlxkrkgcpgvq.supabase.co",
      },
      {
        protocol: 'https',
        hostname: 'images.unsplash.com',
      },
      {
        protocol: 'https',
        hostname: 'loremflickr.com',
      },
    ],
  },
};

export default nextConfig;

Conclusion

The Next.js Image component is an essential tool for optimizing image rendering and enhancing website performance. Its features, including automatic optimization, lazy loading, and responsive image handling, offer substantial benefits in terms of performance, SEO, and developer experience. Configuring next.config.mjs to incorporate external image domains ensures that images from sources like images.unsplash.com can be effectively optimized, further improving the performance of your Next.js application.

By utilizing the Next.js Image component, developers can build faster, more efficient, and SEO-friendly websites with minimal effort.