Fairy Tale Image Generation Server (Using MidJourney Proxy)

This project generates fairy tale character and background images using MidJourney and allows users to monitor the progress of image creation. Since MidJourney doesn't provide an official API, this server interacts with the MidJourney Proxy (novicezk/midjourney-proxy) to handle messages from the MidJourney Discord server.

Character Prompt Generation: There are two methods for generating character prompts:

1. Selecting options for the protagonist's appearance (e.g., hairstyle, facial expression).
2. Creating a character that closely resembles a hand-drawn sketch.

Process Overview

Features

• Image Generation Request: Accepts studentTaskId, fairy tale ID, and prompts for both characters and backgrounds from the client.
• Main Character Image Creation: Generates the main character image first to maintain consistent style across all images.
• Asynchronous Image Generation: Once the reference image is ready, other character and background images are processed in parallel, without waiting for all images to complete.
• Image Progress Monitoring: Clients can query the API periodically to check the progress, imageUrl, and the overall completed or error status.

Image Generation Workflow

1. Client Request: The server receives studentTaskId, fairy tale ID, and prompts for characters and background.
2. Main Character Image Creation: The server sends an image creation request to the MidJourney Proxy for the main character, which serves as a reference image for the rest.
3. Asynchronous Image Creation: Once the reference image is ready, other images (characters and background) are processed concurrently in the background.
4. Post-processing: After image generation, images may go through post-processing such as background removal or blurring.

Detailed Image Generation Steps

1. IMAGINE Request:

   • The server sends an IMAGINE request to the MidJourney Proxy.
   • The server fetches the status periodically and updates Firebase with the success/failure status until the process is complete.

2. UPSCALE Request:

   • After the IMAGINE request generates four images, the server requests to upscale a specific index.
   • The UPSCALE request is also handled by periodically fetching its status, and the final image is saved.

Main API Endpoints

1. Image Generation Request

Handles the initial request to generate character and background images using the provided prompts.

2. Image Status Query

Returns the current progress, image URL, and completion/error status for the images being generated.

3. Regenerate Image API

Allows the client to regenerate a specific image by providing the imageId. This API triggers the creation of only the selected image without affecting the others.

MidJourney Proxy Config Updates

• Timeout Configuration: Resolved issues where some image generation progress wasn't being properly tracked. Set IMAGINE timeout to 2 minutes and UPSCALE timeout to 30 seconds.
• Concurrency Adjustments: Adjusted coreSize and queueSize based on the MidJourney Pro Plan, allowing for 12 concurrent tasks.