AI Sprite Image Generator

A TypeScript library and CLI tool to generate high-quality sprite images using Nano Banana Pro via kie.ai.

Possibly the quickest, easiest and most cost-effective way to generate large batches of consistent images for logos, thumbnails, game assets, product photos, and more.

✨ Try it now with this one-liner:

KIE_API_KEY="your-kie-api-key" bunx ai-sprite-image-generator "Cat photos"

Use Cases

Suitable for any scenario where density, speed and/or image consistency is preferable to raw image quality, such as:

• Logo or icon design ideas
• Thumbnails
• Game assets
• Product photos
• Placeholder images for development

Examples

Cats	Product Photos
Avatars	Animals
Game Assets	Logo / Icon Design Ideas

See integration-test.ts for example prompts and usage.

Features

• 🚀 Fast parallel batch processing - Process batches concurrently to generate 100s of images in seconds
• ✂️ Image splitting - Automatically crops sprite sheets into individual images
• ⏱️ Rate limiting - Respects KIE AI API limits (20 requests per 10 seconds)
• 🎨 Optimized prompts - Automatically enhances your prompts for consistent sprite sheet generation
• 🖼️ Output consistency - Consistent art style between images
• 💰 Cost effective - Generate 25 images for the price of a single image on other platforms

Pricing Comparison

At time of writing:

• A single 1k image on fal.ai costs $0.15
• A 4k 4096x4096px image on kie.ai costs $0.12

By generating a 5x5 sprite sheet using KIE AI we can generate 25 820x820px images for $0.0048 each.

Tip

That's 30x cheaper!

Installation

npm install ai-sprite-image-generator

pnpm add ai-sprite-image-generator

bun add ai-sprite-image-generator

Usage

CLI Usage

The package includes a CLI for quick image generation from the command line.

Installation

npm install -g ai-sprite-image-generator

Set your KIE AI API token as an environment variable:

export KIE_API_KEY="your-kie-api-key"

Basic Commands

# Generate 25 random images (5x5 grid)
ai-sprite-image-generator "Photos of cats"

# Generate specific named items
ai-sprite-image-generator "Furniture product photos" --cells "Chair,Table,Sofa,Lamp"

By default, your generated photos will be in ./out/.

Reading Cells from Stdin

You can pipe cell names from a file or command (newline or comma-separated):

# From a file (one item per line)
cat items.txt | ai-sprite-image-generator "Product photos"

# From echo (comma-separated)
echo "Cat,Dog,Bird,Fish" | ai-sprite-image-generator "Animal avatars"

CLI Options

USAGE:
  ai-sprite-image-generator <prompt> [options]

OPTIONS:
  -c, --cells <items>      Comma or newline-separated list of cell names
  -o, --output <path>      Output directory (default: ./out)
  -x, --columns <n>        Grid columns (default: 5)
  -y, --rows <n>           Grid rows (default: 5)
  -a, --aspect-ratio <r>   Aspect ratio: 1:1, 2:3, 3:2, 4:3, 16:9, etc. (default: 1:1)
  -r, --resolution <r>     Resolution: 1K, 2K, 4K (default: 4K)
  -f, --format <fmt>       Output format: png, jpg (default: png)
  -m, --model <name>       AI model name (default: nano-banana-pro)
  --concurrency <n>        Max concurrent batches (default: 10)
  --existing <mode>        Handle existing files: overwrite, skip (default: overwrite)
  -q, --quiet              Suppress verbose output
  -h, --help               Show help message
  -v, --version            Show version number

CLI Examples

# Generate with custom grid size (3x3 = 9 images per batch)
ai-sprite-image-generator "Animal avatars" -x 3 -y 3

# Output to specific directory in JPG format
ai-sprite-image-generator "Logo designs" -o ./logos --format jpg

# Skip existing files instead of overwriting
ai-sprite-image-generator "Game assets" --existing skip

# Quiet mode (minimal output)
ai-sprite-image-generator "Thumbnails" -q

TypeScript Library

Basic Usage

import { generateImages } from 'ai-sprite-image-generator';

const kieApiKey = 'your-kie-api-key';

const prompt = 'Photos of cats';

const result = await generateImages(kieApiKey, prompt);

console.log('Generated images:', result.imagePaths);

// Generated images: ['out/images/image-1.png', 'out/images/image-2.png', ...]

With Named Items

To specify specific items for each cell, pass an array of strings. Requests will be batched based on the grid size (e.g. 5x5 = 25 items per batch):

import { generateImages } from 'ai-sprite-image-generator';

const kieApiKey = 'your-kie-api-key';

const prompt = 'Furniture product photos';

const cells = ['Chair', 'Dinner Table', 'Sofa', 'Lamp', 'Bookshelf', 'Desk'];

const result = await generateImages(
  kieApiKey,
  prompt,
  {
    outputPath: './furniture',
  },
  cells,
);

console.log('Generated images:', result.imagePaths);
// Generated images: ['./furniture/images/chair.png', './furniture/images/dinner-table.png', ...]

API Reference

generateImages(apiKey, prompt, options?, cells?)

Main function to generate sprite images.

See lib.ts for full implementation.

Parameters:

• apiKey (string) - Your KIE AI API token - Get one here
• prompt (string) - Base prompt describing the desired image style
• options (ImageGenerationOptions) - Optional configuration
• cells (string[] | CellDefinition[]) - Optional array of cell names or definitions

Returns: Promise<ImageGenerationResult>

Types

interface ImageGenerationOptions {
  rows: number; // Grid rows (default: 5)
  columns: number; // Grid columns (default: 5)
  outputPath: string; // Output directory (default: './out')
  aspectRatio: AspectRatio; // Image aspect ratio (default: '1:1')
  resolution: Resolution; // Image resolution (default: '4K')
  outputFormat: OutputFormat; // Output format (default: 'png')
  maxConcurrentBatches: number; // Max parallel batches (default: 10)
  pollIntervalMs: number; // Polling interval (default: 5000)
  maxPollAttempts: number; // Max poll attempts (default: 60)
  maxRetries: number; // Max retries for failures (default: 3)
  model: string; // AI model to use (default: 'nano-banana-pro')
  verbose: boolean; // Enable console logging (default: true)
}

interface ImageGenerationResult {
  batchImagePaths: string[]; // Paths to sprite sheet images
  imagePaths: string[]; // Paths to individual cell images
  errors: Array<{ batchIndex: number; error: Error }>;
  totalBatches: number;
  successfulBatches: number;
}

Contributing

Install dependencies:

bun install

Run lint/format/typecheck (and auto-fix where possible):

bun fix

Run tests:

bun test

Build package:

bun run build

Maintainers

• David Taylor