How to Convert Images to WebP Format in Linux?

In today's digital age, images play a vital role in websites and various digital projects. But, the larger the image size, the longer it takes to load, leading to a poor user experience. Fortunately, Google has developed the WebP image format, which offers superior compression and quality compared to traditional image formats like JPEG and PNG. In this article, we will delve into how you can convert images to the WebP format on Linux using the WebP tools. By converting your images to WebP format, you can significantly reduce their file size, which in turn boosts website performance and enhances user experience.

Step 1: Install WebP Tools

First, you need to install the WebP tools package on your Linux system. Open the terminal and run the following command

sudo apt-get install webp

The following command will generate the output like this

Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following NEW packages will be installed:
  webp
0 upgraded, 1 newly installed, 0 to remove and 10 not upgraded.
Need to get 89.6 kB of archives.
After this operation, 292 kB of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu bionic/main amd64 webp amd64 0.6.1-2 [89.6 kB]
Fetched 89.6 kB in 1s (86.6 kB/s)       
Selecting previously unselected package webp.
(Reading database ... 146234 files and directories currently installed.)
Preparing to unpack .../webp_0.6.1-2_amd64.deb ...
Unpacking webp (0.6.1-2) ...
Setting up webp (0.6.1-2) ...
Processing triggers for man-db (2.8.3-2ubuntu0.1) ...

Once the installation is complete, verify that the WebP tools are installed by running the following command

cwebp -version

Here's the terminal output for the cwebp -version command

WebP Encoder version 1.1.0

This output shows the version of the cwebp command, which is used to convert images to WebP format in Linux.

Step 2: Convert Images to WebP Format

Basic Conversion Syntax

The basic syntax for converting images to WebP format is

cwebp [options] input_file -o output_file

Here's the detailed explanation of each part

• cwebp This is the command to convert images to WebP format.

• [options] These are optional arguments that you can use to customize the output image. The -q option specifies the quality of the output image.

• input_file This is the name of the image file that you want to convert.

• -o This option specifies the output file name.

• output_file This is the name you want to give the output file.

Converting a Single Image

First, navigate to the directory containing your image

cd ~/Pictures

Then convert the image using the following command

cwebp -q 80 my_image.jpg -o my_image.webp

You may get terminal output similar to this

Input file size: 654 KB
Output file size: 215 KB

In this example, we've used the -q option to set the quality of the output image to 80 (out of 100). This achieves significant file size reduction while maintaining good image quality.

Step 3: Batch Conversion

When you have multiple images to convert to WebP format, you can use a loop to convert all the images in a directory at once. Here's how to do it

Navigate to the directory containing the images you want to convert, then use the following command to convert all JPEG images

for i in *.jpg; do cwebp -q 80 "$i" -o "${i%.jpg}.webp"; done

Let's break down this command

• for i in *.jpg A loop that iterates over each file in the directory that has a .jpg extension.

• cwebp -q 80 "$i" -o "${i%.jpg}.webp" Converts each image to WebP format with quality 80.

• ${i%.jpg} Removes the .jpg extension from the input file name.

• done Ends the loop.

For PNG images, modify the command accordingly

for i in *.png; do cwebp -q 80 "$i" -o "${i%.png}.webp"; done

Common WebP Conversion Options

Converting WebP Back to Other Formats

You can also convert WebP images back to other formats using the dwebp command

dwebp input.webp -o output.png

Conclusion

Converting images to WebP format is an effective way to optimize website performance by significantly reducing file sizes without compromising image quality. The cwebp command provides flexible options for both single and batch conversions, making it easy to integrate into your workflow and improve overall user experience.