Welcome to the first lesson of our course, "Creating Images with Gemini's Imagen and Java". In this course, you will explore the fascinating world of AI-driven image generation using Google's Gemini API and its Imagen model. Our journey begins with understanding how to set up the environment and generate a simple image. This foundational lesson will set the stage for more advanced topics in subsequent units.

Before we dive into generating images, it's crucial to set up our environment correctly. First, ensure you have access to the Gemini API by retrieving your API key. This key is essential for authenticating your requests to the API. You can set this key as an environment variable or store it in a .env file. For this lesson, you'll need to set up a Java project using Gradle to manage dependencies. Here's how you can set up a Gradle project:

build.gradle

With the environment set up, the next step is to configure the Gemini API client. This involves initializing the client with your API key and base URL, which can be loaded from environment variables or a .env file. Here’s how you can load these values in Java:

In the CodeSignal environment, the GEMINI_API_KEY and GEMINI_BASE_URL environment variables are already set up for you. If you are working on your own machine, you will need to provide a valid API key and base URL yourself.

Now, let's generate a simple image using the Imagen model. We'll start by defining a prompt, which is a textual description of the image you want to create. In this example, the prompt is "A serene sunset over a mountain range." We'll use Java's HTTP client to make a request to the Gemini API and handle the JSON response:

Once the image is generated, the next step is to process and display it. The response from the API contains the image data in base64 format, which can be decoded and saved to a file:

In this lesson, you learned how to set up your Java environment, configure the Gemini API client, and generate a simple image using a prompt. We also explored how to process and save the generated image. This foundational knowledge will be crucial as you progress through the course. As you move on to the practice exercises, I encourage you to experiment with different prompts and configurations to see the diverse range of images you can create. This hands-on practice will solidify your understanding and prepare you for more advanced topics in the upcoming lessons.