HeyGen Avatar IV
HeyGen Avatar IV is a photorealistic AI avatar generation model that creates talking videos from a single image and a script or audio input. The model synchronizes voice with facial motion, expressions, and gestures to produce lifelike avatar performances. It supports multilingual speech, realistic lip synchronization, and expressive body language, enabling scalable production of presenter-style videos without cameras, actors, or studio setups.
Retro-Futurist Observatory Presenter Portrait
{
"taskType": "videoInference",
"taskUUID": "b8a0b08e-e8d5-433c-8527-4397dfa76806",
"model": "heygen:avatar@4",
"positivePrompt": "A polished science explainer video with a photorealistic presenter composited naturally into a retro-futurist observatory scene. The speaker appears warm, articulate, and credible, with subtle head motion, realistic blinking, expressive eyebrows, and natural hand gestures. Lighting should blend the portrait seamlessly with the amber-and-violet environment for a premium educational broadcast look.",
"width": 1280,
"height": 720,
"speech": {
"text": "Welcome to tonight's sky report. Behind me, the observatory has mapped a rare ionized cloud drifting across the outer spiral arm. Notice how the violet plume bends around the denser star cluster at upper right. That curve tells us the gas is being shaped by powerful stellar winds. In the next few seconds, I will walk you through what that means, why it matters, and how scientists turn patterns of light into a story about motion, temperature, and time.",
"voice": "sophia_narration_friendly_female_english",
"speed": 1,
"pitch": 0,
"language": "en-US"
},
"settings": {
"expressiveness": "high",
"removeBackground": false
},
"inputs": {
"image": "https://assets.runware.ai/assets/inputs/8077b160-f135-40f8-aa5e-ad9cd0dc3020.jpg",
"background": "https://assets.runware.ai/assets/inputs/191ca5bb-637f-4239-a379-e0ed78553bd1.jpg"
}
}{
"taskType": "videoInference",
"taskUUID": "b8a0b08e-e8d5-433c-8527-4397dfa76806",
"videoUUID": "86bea572-6922-45f9-81a8-217810634bfc",
"videoURL": "https://vm.runware.ai/video/os/a04d20/ws/5/vi/86bea572-6922-45f9-81a8-217810634bfc.mp4",
"cost": 2.8866
}Vintage Planetarium Lecture Hall
{
"taskType": "videoInference",
"taskUUID": "5893b754-1341-468b-a130-0c8c07d4e68f",
"model": "heygen:avatar@4",
"positivePrompt": "A photorealistic talking educator delivering a refined science presentation in a vintage planetarium lecture hall, natural head motion, subtle hand gestures, accurate lip sync, warm academic atmosphere, polished professional framing",
"width": 1280,
"height": 720,
"speech": {
"text": "Welcome to tonight's sky lesson. Before digital simulations, people built mechanical models to explain how planets appeared to wander across the heavens. This brass orrery behind me turns abstract motion into something you can almost hold in your hands. Watch how a calm voice, realistic facial movement, and small gestures make this avatar feel like a real museum guide.",
"voice": "professor_dean_male_english",
"language": "en-US",
"speed": 1,
"pitch": 0
},
"settings": {
"expressiveness": "high",
"removeBackground": true
},
"inputs": {
"image": "https://assets.runware.ai/assets/inputs/9292e6b5-0ed7-4919-acfb-f62fa6b72238.jpg",
"background": "https://assets.runware.ai/assets/inputs/f7fb9341-681d-494d-ad7c-80a53361c047.jpg"
}
}{
"taskType": "videoInference",
"taskUUID": "5893b754-1341-468b-a130-0c8c07d4e68f",
"videoUUID": "8729f343-87a3-459a-8dc9-e18054b595ed",
"videoURL": "https://vm.runware.ai/video/os/a18d05/ws/5/vi/8729f343-87a3-459a-8dc9-e18054b595ed.mp4",
"cost": 2.413
}Floating Conservatory Weather Briefing
{
"taskType": "videoInference",
"taskUUID": "84e2ed45-8ec1-42b4-aa56-a0d9559fba09",
"model": "heygen:avatar@4",
"positivePrompt": "A friendly young female presenter framed from the waist up, standing naturally and speaking to camera with warm confidence, casual contemporary styling, realistic facial motion, subtle hand gestures, photorealistic broadcast composition, composited over a luminous greenhouse overlook at sunrise",
"width": 1280,
"height": 720,
"speech": {
"text": "Good morning from the hillside conservatory. Today’s outlook is bright and steady, with gentle cloud bands drifting in from the west by late afternoon. Growers in the valley can expect mild temperatures, comfortable humidity, and ideal conditions for pollination through most of the day. If you are planning field work, the clearest window runs from nine to three, before a cooler breeze arrives near sunset. In short: calm skies, soft light, and a very cooperative day ahead.",
"voice": "sophia_narration_friendly_female_english",
"language": "en-US"
},
"inputs": {
"avatar": "woman_casual_young_adult",
"background": "https://assets.runware.ai/assets/inputs/eda3a1cf-1b86-4e00-b84f-7af8483575da.jpg"
}
}{
"taskType": "videoInference",
"taskUUID": "84e2ed45-8ec1-42b4-aa56-a0d9559fba09",
"videoUUID": "acfc3438-3f65-4b40-9511-e8c700802153",
"videoURL": "https://vm.runware.ai/video/os/a22d05/ws/5/vi/acfc3438-3f65-4b40-9511-e8c700802153.mp4",
"cost": 3.038
}Midnight Vinyl Radio Host
{
"taskType": "videoInference",
"taskUUID": "a9038d0e-b8ab-4d4d-8f18-d655a92e2dd7",
"model": "heygen:avatar@4",
"positivePrompt": "Photorealistic male studio host framed waist-up in a cozy vintage-inspired FM broadcast booth, brushed walnut panels, glowing VU meters, stacked vinyl records, foam sound baffles, soft amber practical lights, classic silver microphone on boom arm, subtle reflections on glass, relaxed posture, direct eye contact with camera, cinematic shallow depth of field, rich realistic skin texture, polished late-night broadcast atmosphere",
"width": 1280,
"height": 720,
"speech": {
"text": "Good evening, night owls. You’ve tuned in to the quiet hour, where the city softens, the traffic thins, and even the brightest signs seem to hum instead of shout. Tonight’s theme is forgotten songs: the tracks you heard once in a diner, on a borrowed cassette, or through an open window, and somehow never forgot. If one of those melodies is still following you years later, maybe it never really belonged to the past. Maybe it was waiting for you to listen again.",
"voice": "radio_rick_male_english",
"language": "en-US"
},
"inputs": {
"avatar": "man_casual_young_adult_2"
}
}{
"taskType": "videoInference",
"taskUUID": "a9038d0e-b8ab-4d4d-8f18-d655a92e2dd7",
"videoUUID": "aa77d401-d8e6-4d94-b203-34fcdc884785",
"videoURL": "https://vm.runware.ai/video/os/a25d05/ws/5/vi/aa77d401-d8e6-4d94-b203-34fcdc884785.mp4",
"cost": 2.7223
}Art Deco Transit Concierge
{
"taskType": "videoInference",
"taskUUID": "1510d4e7-17fc-4e9b-ac39-63e4bea2f6aa",
"model": "heygen:avatar@4",
"positivePrompt": "A poised concierge delivering clear travel guidance with natural hand gestures, warm eye contact, subtle smile, refined professional presence, realistic lip sync, polished broadcast framing",
"width": 1280,
"height": 720,
"speech": {
"text": "Welcome to Meridian Central. If this is your first time here, the east concourse handles regional departures, the west concourse connects to long-distance routes, and the mezzanine level offers ticketing support, lounge access, and baggage services. Follow the gold wayfinding lines on the floor for the fastest path to your platform.",
"voice": "claire_cheerful_female_english",
"language": "en-US",
"speed": 0.98,
"pitch": 1.2
},
"settings": {
"expressiveness": "high"
},
"inputs": {
"image": "https://assets.runware.ai/assets/inputs/af1ba04d-13f1-43f3-bd25-1fd50341feb9.jpg",
"background": "https://assets.runware.ai/assets/inputs/e7e700da-0c91-4355-a432-f796d3c09f54.jpg"
}
}{
"taskType": "videoInference",
"taskUUID": "1510d4e7-17fc-4e9b-ac39-63e4bea2f6aa",
"videoUUID": "f6011370-c2e6-4408-a51b-0e1317026068",
"videoURL": "https://vm.runware.ai/video/os/a12d13/ws/5/vi/f6011370-c2e6-4408-a51b-0e1317026068.mp4",
"cost": 2.1164
}