Google Imagen vs Qwen-Image 2.1 (Model Studio)

Google Imagen

Shutdown dates were published in the Gemini API changelog and the Vertex AI release notes, with replacements named. Discontinued. Calls to imagen model names fail on both the Gemini API and Vertex AI.

Qwen-Image 2.1 (Model Studio)

qwen-image-2.1-pro generates and edits images with up to 10 references and transparent output, at $0.04 an image in Singapore, through an OpenAI-compatible endpoint or DashScope. Model Studio publishes a 99.9 per cent SLA and a no-training statement. The model allows 20 requests a minute, has no OpenAPI file, and its open weights are for non-commercial use only.

Google Imagen

1. Replace client.models.generate_images with client.models.generate_content and a gemini-3.1-flash-image model
2. Read images from the response content parts, not from generated_images
3. Don't budget from the Vertex Imagen price rows, they describe a retired product
4. If the job needs a mask-based inpaint, use another vendor's fill endpoint, since Gemini image editing is prompt-based

Qwen-Image 2.1 (Model Studio)

1. Use the same region for the key, the model and the endpoint. Cross-region calls fail
2. Download each result within 24 hours. The URL expires and the image is purged
3. With the OpenAI SDK, pass image, seed, prompt_extend and watermark through extra_body, and write size as 1024x1024, not 1024*1024
4. Set a client timeout of up to 600 seconds for several outputs, or use the async DashScope call and poll the task id
5. Do not send prompt_extend_mode: agent with input images. It returns 400