Runway Core Workflow A
Overview
Advanced text-to-video generation: prompt engineering, model selection, parameter tuning, and batch generation.
Prerequisites
- Completed
runway-hello-world
Instructions
Step 1: Model Selection
from runwayml import RunwayML
client = RunwayML()
# Available models:
# gen3a_turbo — Fast, lower cost, good quality
# gen4_turbo — Latest model, highest quality
task = client.image_to_video.create(
model='gen4_turbo',
prompt_text='A futuristic cityscape at night with flying cars and neon signs, cyberpunk aesthetic',
duration=10,
ratio='16:9',
)
result = task.wait_for_task_output()
Step 2: Prompt Engineering Tips
# Structure: Subject + Action + Setting + Style + Camera
prompts = [
# Good: specific, visual, stylistic
"A red fox walking through a snowy forest, soft winter light, documentary style, tracking shot",
# Good: detailed motion and camera
"Waves of golden wheat swaying in the wind, drone flyover, warm sunset, cinematic grain",
# Bad: too abstract
# "Something beautiful happening" — too vague
]
Step 3: Batch Generation
import asyncio
prompts = [
"A butterfly emerging from a cocoon, macro lens, time-lapse, studio lighting",
"Rain falling on a Tokyo street at night, reflections, neon, dolly zoom",
"A chef preparing sushi in a traditional kitchen, close-up, warm lighting",
]
tasks = []
for prompt in prompts:
task = client.image_to_video.create(
model='gen3a_turbo',
prompt_text=prompt,
duration=5,
)
tasks.append(task)
print(f"Queued: {task.id}")
# Wait for all
for task in tasks:
result = task.wait_for_task_output()
status = "OK" if result.status == "SUCCEEDED" else "FAILED"
print(f" {task.id}: {status}")
Step 4: Output Format Options
task = client.image_to_video.create(
model='gen3a_turbo',
prompt_text='Abstract paint mixing in slow motion, vibrant colors, black background',
duration=5,
ratio='9:16', # Vertical for mobile/TikTok
# ratio='16:9', # Landscape for YouTube
# ratio='1:1', # Square for Instagram
)
Output
- Videos generated with optimal model selection
- Prompt engineering best practices applied
- Batch generation for multiple videos
- Output in various aspect ratios
Error Handling
| Issue | Cause | Solution | |-------|-------|----------| | Low quality | Gen3a_turbo for complex scene | Use gen4_turbo for higher quality | | Content rejection | Policy violation | Remove violent/explicit content from prompt | | Slow generation | High queue | Use turbo model or try later | | Wrong aspect ratio | Not specified | Always set ratio explicitly |
Resources
Next Steps
Image-to-video: runway-core-workflow-b