How to change the DPI of a photo in Java

Adjusting the dots per inch of a photo can have huge value when it comes time to print or web display an image. Being able to adjust this to a common value en mass is the focus of today’s tutorial. We will be using a Cloudmersive API to painlessly complete this chore, and we will do it in under 5 minutes. Let’s get started.

First we need to edit our Maven POM file and add two references.

Repository reference:


Dependency reference:


All that’s left is to call convertImageImageSetDPI and provide it with a file and desired DPI value:

// Import classes://import com.cloudmersive.client.invoker.ApiClient;//import com.cloudmersive.client.invoker.ApiException;//import com.cloudmersive.client.invoker.Configuration;//import com.cloudmersive.client.invoker.auth.*;//import com.cloudmersive.client.ConvertImageApi;ApiClient defaultClient = Configuration.getDefaultApiClient();// Configure API key authorization: ApikeyApiKeyAuth Apikey = (ApiKeyAuth) defaultClient.getAuthentication("Apikey");Apikey.setApiKey("YOUR API KEY");// Uncomment the following line to set a prefix for the API key, e.g. "Token" (defaults to null)//Apikey.setApiKeyPrefix("Token");ConvertImageApi apiInstance = new ConvertImageApi();Integer dpi = 56; // Integer | New DPI in pixels-per-inch, for example 300 DPI or 600 DPIFile inputFile = new File("/path/to/file"); // File | Input file to perform the operation on.try {byte[] result = apiInstance.convertImageImageSetDPI(dpi, inputFile);System.out.println(result);} catch (ApiException e) {System.err.println("Exception when calling ConvertImageApi#convertImageImageSetDPI");e.printStackTrace();}

That’s it! Our image will now have the desired DPI. Our APIs provide a plethora of other image-related functionality, including converting between image formats, resizing, and facial recognition, so be sure to check out our documentation section.

Image for post
Image for post

Written by

There’s an API for that. Cloudmersive is a leader in Highly Scalable Cloud APIs.

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store