Runwayml Gen4 Image API Documentation

Runwayml Gen4 Image API Documentation

Playground

RunwayML Gen4 Image model lets you generate precise images using up to 3 reference images to capture every angle and detail. Ready-to-use REST inference API, best performance, no coldstarts, affordable pricing.

Features

RunwayML Gen4 Image is a powerful text-to-image generation model from Runway that creates high-quality images from text descriptions. With optional reference image support, flexible aspect ratios, and resolution choices, it delivers stunning visuals for creative and professional projects.

Why It Stands Out

• High-quality generation: Produces detailed, visually striking images with excellent composition.
• Prompt Enhancer: Built-in AI-powered prompt optimization for better image results.
• Reference image support: Optionally include reference images to guide style or subject consistency.
• Flexible aspect ratios: Choose from 1:1, 16:9, 9:16, 4:3, or 3:4 to fit any use case.
• Resolution options: Generate at 720p for speed or 1080p for maximum detail.
• Reproducibility: Use the seed parameter to recreate exact results.

Parameters

Supported Aspect Ratios

How to Use

1. Write a prompt describing the image you want. Use the Prompt Enhancer for AI-assisted optimization.
2. Select aspect ratio — choose the format that fits your use case.
3. Choose resolution — select 720p for faster generation or 1080p for higher quality.
4. Add reference images (optional) — upload images to guide style or subject consistency.
5. Set a seed (optional) for reproducible results.
6. Click Run and download your image.

Best Use Cases

• Creative Art & Illustration — Generate unique artwork and digital illustrations.
• Social Media Content — Create platform-optimized visuals for any channel.
• Marketing & Advertising — Produce eye-catching visuals for campaigns.
• Concept Art — Quickly visualize ideas and creative directions.
• Style Transfer — Use reference images to maintain consistent aesthetics across projects.

Pricing

Pro Tips for Best Quality

• Be descriptive in your prompt — include style, mood, lighting, composition, and specific details.
• Use reference images when you need consistent style or subject appearance across multiple generations.
• Choose 720p for quick drafts and iterations, 1080p for final outputs.
• Select the appropriate aspect ratio for your intended platform before generating.
• Fix the seed when iterating to compare different prompt variations.

Notes

• Ensure uploaded reference image URLs are publicly accessible.
• Processing time varies based on resolution and current queue load.
• Please ensure your prompts comply with content guidelines.

Authentication

For authentication details, please refer to the Authentication Guide.

API Endpoints

Submit Task & Query Result

set -euo pipefail

export WAVESPEED_API_KEY="your-api-key"

REQUEST_BODY=$(cat <<'JSON'
{
  "prompt": "A cinematic ocean wave at sunrise, highly detailed",
  "aspect_ratio": "4:3",
  "resolution": "1080p"
}
JSON
)

# 1. Submit the prediction.
SUBMIT_RESPONSE=$(curl --silent --show-error --fail-with-body \
  -X POST "https://api.wavespeed.ai/api/v3/runwayml/gen4-image" \
  -H "Authorization: Bearer ${WAVESPEED_API_KEY}" \
  -H "Content-Type: application/json" \
  -d "${REQUEST_BODY}")

TASK=$(printf '%s' "${SUBMIT_RESPONSE}" | jq 'if type == "object" and has("data") then .data else . end')
PREDICTION_ID=$(printf '%s' "${TASK}" | jq -r '.id // empty')
if [ -z "${PREDICTION_ID}" ]; then
  printf 'Submission response did not contain a prediction id
' >&2
  exit 1
fi
RESULT_URL=$(printf '%s' "${TASK}" | jq -r '.urls.get // empty')
if [ -z "${RESULT_URL}" ]; then RESULT_URL="https://api.wavespeed.ai/api/v3/predictions/${PREDICTION_ID}/result"; fi

# 2. Poll until the prediction finishes.
while true; do
  RESPONSE=$(curl --silent --show-error --fail-with-body \
    "${RESULT_URL}" \
    -H "Authorization: Bearer ${WAVESPEED_API_KEY}")
  RESULT=$(printf '%s' "${RESPONSE}" | jq 'if type == "object" and has("data") then .data else . end')
  STATUS=$(printf '%s' "${RESULT}" | jq -r '.status // empty')

  case "${STATUS}" in
    completed) printf '%s\n' "${RESULT}" | jq '.outputs'; break ;;
    failed|cancelled|timeout) printf '%s\n' "${RESULT}" | jq . >&2; exit 1 ;;
    created|processing) sleep 2 ;;
    *) printf 'Unexpected status: %s
' "${STATUS}" >&2; exit 1 ;;
  esac
done

Parameters

Task Submission Parameters

Request Parameters

Response Parameters

Result Request Parameters

Result Response Parameters