Submit Video Task - LeapX API Documentation

Introduction

The submit video task API is used to create a new video generation task. Upon successful submission, it returns a task ID that you can use to query the task status. Important Note: Video generation is an asynchronous task. You need to first submit a task to get a task ID, then poll the task status until it succeeds.

Authentication

Authorization

string

required

Bearer Token, e.g. Bearer sk-xxxxxxxxxx

Request Parameters

model

string

required

Model identifier, supported models and features:Sora 2 Series:

sora-2 - Supports text-to-video, image-to-video, video-to-video (Remix mode)

Google Veo Series:

veo-3.0-fast-generate-001 - Text-to-video (first frame mode)
veo-3.1-fast-generate-preview - Text-to-video (first frame mode, first/last frame mode)

Ali Wanxiang Series:

wan2.5-t2v-preview - Text-to-video
wan2.5-i2v-preview - Image-to-video (first frame mode)

Doubao Seedance Series:

doubao-seedance-1-0-lite-t2v-250428 - Text-to-video
doubao-seedance-1-0-lite-i2v-250428 - Image-to-video (first frame mode, first/last frame mode, reference image mode)
doubao-seedance-1-0-pro-250528 - Text-to-video (first frame mode)
doubao-seedance-1-5-pro-251215 - Text-to-video, image-to-video (first frame mode, first/last frame mode), supports audio generation
doubao-seedance-1-5-pro-251215-noAudio - Text-to-video, image-to-video (first frame mode, first/last frame mode), no audio generation

prompt

string

Video generation prompt, describing scene actions and settings. Note: Doubao Seedance series models do not require this field, the prompt should be written directly in the text field of the metadata.content array

image

string

Reference image for image-to-video (supports Base64 or URL format)

duration

integer

default:"5"

Video duration (seconds), different models support different durations

resolution

string

default:"720p"

Video resolution: 480p, 720p, 1080p, 4k

aspect_ratio

string

default:"16:9"

Aspect ratio: 16:9, 9:16, 1:1, 4:3, 3:4, 21:9, adaptive (adaptive, only supported by some models)

Model-Specific Parameters

Different models support different specific parameters. Below are detailed descriptions by model series:

Sora 2
Veo
Ali Wanxiang
Doubao Seedance

seconds

string|integer

default:"4"

Video duration (seconds), supports: 4, 8, 12

size

string

default:"720x1280"

Video resolution, supports: 720x1280 (portrait), 1280x720 (landscape)

input_reference

string

Reference image (supports URL or Base64 format), for image-to-video

remix_from_video_id

string

Remix mode: Regenerate based on existing video ID (must start with video_)

durationSeconds

integer

default:"4"

Video duration (seconds), supports: 4, 6, 8

aspectRatio

string

default:"16:9"

Aspect ratio, only supports: 16:9, 9:16

resolution

string

default:"1080p"

Resolution, supports: 720p, 1080p

fps

integer

default:"24"

Frame rate, default 24

image

string

First frame reference image (supports URL or Base64 format)

lastFrame

string

Last frame reference image (supports URL or Base64 format), only veo-3.1 series supports

generateAudio

boolean

default:"false"

Whether to generate synchronized audio. Fast models ignore this parameter and always include audio

personGeneration

string

default:"allow_all"

Person generation strategy: allow_all (all ages), allow_adult (adults only), dont_allow (no people)

addWatermark

boolean

default:"false"

Whether to add watermark

seed

integer

Random seed for reproducing results

sampleCount

integer

default:"1"

Number of videos generated each time, range: 1-4

duration

integer

default:"5"

Video duration (seconds), supports: 5, 10

resolution

string

default:"720p"

Video resolution, supports: 480p, 720p, 1080p

size

string

Video size (t2v mode only), format: width*height, e.g. 1280*720

smart_rewrite

boolean

default:"false"

Whether to enable intelligent prompt expansion

generate_audio

boolean

default:"false"

Whether to generate synchronized audio with the video

audio_url

string

Custom audio file URL (HTTPS format)

seed

integer

Random seed, range: 0-2147483647

metadata.content

array

required

Content array, must be placed in the metadata object. Must include text and optional images. Parameters are controlled through special markers in text prompts:

--rs or --resolution: Resolution (480p, 720p, 1080p)
--ratio: Aspect ratio (16:9, 9:16, 1:1, 4:3, 3:4, adaptive, note that doubao-seedance-1-0-lite-t2v-250428 does not support adaptive)
--dur or --duration: Duration (seconds, e.g. 5, 10)
--frames: Frame count (only 1.5 pro series supports). Either --frames or --dur can be used, frames takes priority over duration. If you want fractional-second videos, specify frames. Range: all integers within [29, 289] that match 25 + 4n where n is a positive integer
--fps or --framespersecond: Frame rate (e.g. 24, 30)
--seed: Random seed, integer in range [-1, 2^32-1]
--wm or --watermark: Watermark toggle (true, false)
--cf or --camerafixed: Fixed camera (true, false, only lite models support)

Model Feature Description:

1.0 lite/pro series: doubao-seedance-1-0-lite-t2v-250428, doubao-seedance-1-0-lite-i2v-250428, doubao-seedance-1-0-pro-250528
- Supports basic video generation features
- lite-i2v supports first/last frame mode and reference image mode
- pro models support high resolution (720p/1080p)
1.5 pro series: doubao-seedance-1-5-pro-251215, doubao-seedance-1-5-pro-251215-noAudio
- 1.5-pro: Supports text-to-video and image-to-video (first frame mode, first/last frame mode), automatically generates matching audio
- 1.5-pro-noAudio: Same features as 1.5-pro, but does not generate audio, faster video rendering
- Resolution support: Only supports 480p and 720p (does not support 1080p)
- Duration support: Any integer between 4-12 seconds (e.g. 4, 5, 6, 7, 8, 9, 10, 11, 12)
- Image-to-video modes: Supports first frame mode and first/last frame mode (does not support reference image mode)

metadata.content array format:

{
  "metadata": {
    "content": [
      {
        "type": "text",
        "text": "Prompt content --ratio 16:9 --dur 5 --rs 720p --wm false"
      },
      {
        "type": "image_url",
        "image_url": {
          "url": "data:image/png;base64,..."
        },
        "role": "first_frame"  // Optional: first_frame, last_frame, reference_image
      }
    ],
    "return_last_frame": true,  // Whether to return the last frame (1.5 Pro series)
    "callback_url": "https://your-domain.com/callback"  // Optional callback URL
  }
}

Usage Examples

Sora 2
Veo
Ali Wanxiang
Doubao Seedance

1. Text-to-Video (Basic Example)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "sora-2",
    "prompt": "A cute little cat playing in the garden, sunny and warm",
    "seconds": "4",
    "size": "720x1280"
  }'

2. Text-to-Video (Landscape, 8 seconds)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "sora-2",
    "prompt": "A cute little cat playing in the garden, sunny and warm",
    "seconds": "8",
    "size": "1280x720"
  }'

3. Image-to-Video (First Frame Mode)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "sora-2",
    "prompt": "A cute little cat playing in the garden, sunny and warm",
    "seconds": "4",
    "size": "720x1280",
    "input_reference": "data:image/png;base64,iVBORw0KGgoAAxxxx..."
  }'

4. Remix Mode (Video-to-Video)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "sora-2",
    "prompt": "Change the video to a night scene with stars",
    "seconds": "4",
    "size": "720x1280",
    "remix_from_video_id": "video_69095b4ce0048190893a01510c0c98b0"
  }'

1. Text-to-Video (Basic Example)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "veo-3.1-fast-generate-preview",
    "prompt": "Aerial view of a sci-fi city at dawn, sunlight piercing through clouds",
    "durationSeconds": 8,
    "aspectRatio": "16:9",
    "resolution": "1080p",
    "fps": 24
  }'

2. Image-to-Video (First Frame Mode)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "veo-3.1-fast-generate-preview",
    "prompt": "Generate video based on this image, scene gradually unfolds",
    "durationSeconds": 8,
    "aspectRatio": "16:9",
    "resolution": "1080p",
    "fps": 24,
    "image": "data:image/png;base64,iVBORw0KGgoAAxxxx..."
  }'

3. Image-to-Video (First/Last Frame Mode, only veo-3.1 supports)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "veo-3.1-fast-generate-preview",
    "prompt": "Transition from first image to second image",
    "durationSeconds": 8,
    "aspectRatio": "16:9",
    "resolution": "1080p",
    "fps": 24,
    "image": "data:image/png;base64,iVBORw0KGgoAAxxxx...",
    "lastFrame": "data:image/png;base64,iVBORw0KGgoAAyyyy..."
  }'

1. Text-to-Video (Basic Example)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "wan2.5-t2v-preview",
    "prompt": "A kitten slowly opens its eyes, ears gently twitch, camera slowly pushes in",
    "duration": 5,
    "size": "1280*720",
    "smart_rewrite": true,
    "generate_audio": true
  }'

2. Text-to-Video (10 seconds, 1080p, with Random Seed)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "wan2.5-t2v-preview",
    "prompt": "A kitten slowly opens its eyes, ears gently twitch, camera slowly pushes in",
    "duration": 10,
    "size": "1920*1080",
    "smart_rewrite": false,
    "generate_audio": false,
    "seed": 123456
  }'

3. Image-to-Video (First Frame Mode)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "wan2.5-i2v-preview",
    "prompt": "Kitten slowly opens its eyes, ears gently twitch, camera slowly pushes in",
    "duration": 5,
    "resolution": "720p",
    "smart_rewrite": true,
    "generate_audio": true,
    "image": "data:image/png;base64,iVBORw0KGgoAAxxxx..."
  }'

4. Image-to-Video (with Custom Audio)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "wan2.5-i2v-preview",
    "prompt": "Kitten slowly opens its eyes, ears gently twitch, camera slowly pushes in",
    "duration": 10,
    "resolution": "1080p",
    "smart_rewrite": false,
    "generate_audio": false,
    "audio_url": "https://example.com/audio.mp3",
    "image": "data:image/png;base64,iVBORw0KGgoAAxxxx...",
    "seed": 789012
  }'

1. Text-to-Video (T2V, Basic Example)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "doubao-seedance-1-0-lite-t2v-250428",
    "metadata": {
      "content": [
        {
          "type": "text",
          "text": "A cute kitten playing in a garden, sunny day --ratio 16:9 --dur 5 --rs 720p --wm false"
        }
      ]
    }
  }'

2. Text-to-Video (T2V, Full Parameters)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "doubao-seedance-1-0-lite-t2v-250428",
    "metadata": {
      "content": [
        {
          "type": "text",
          "text": "A cute kitten playing in a garden, sunny day --ratio 9:16 --dur 10 --rs 1080p --fps 30 --wm true --seed 12345"
        }
      ]
    }
  }'

3. Image-to-Video (First Frame Mode)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "doubao-seedance-1-0-lite-i2v-250428",
    "metadata": {
      "content": [
        {
          "type": "text",
          "text": "A girl opens her eyes and looks gently at the camera --ratio adaptive --dur 5 --rs 720p --wm false"
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "data:image/png;base64,iVBORw0KGgoAAxxxx..."
          }
        }
      ]
    }
  }'

4. Image-to-Video (First/Last Frame Mode, lite-i2v and 1.5 pro support)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "doubao-seedance-1-0-lite-i2v-250428",
    "metadata": {
      "content": [
        {
          "type": "text",
          "text": "A blue-green jingwei bird transforms into human form --rs 720p --dur 5 --fps 24 --cf false --wm false --seed 67890"
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "data:image/png;base64,iVBORw0KGgoAAxxxx..."
          },
          "role": "first_frame"
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "data:image/png;base64,iVBORw0KGgoAAyyyy..."
          },
          "role": "last_frame"
        }
      ]
    }
  }'

5. Image-to-Video (Reference Image Mode, only lite-i2v supports)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "doubao-seedance-1-0-lite-i2v-250428",
    "metadata": {
      "content": [
        {
          "type": "text",
          "text": "[图1] A boy wearing glasses and blue T-shirt and [图2] corgi dog, sitting on [图3] lawn, 3D cartoon style --rs 720p --dur 5 --ratio 16:9 --wm false"
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "https://example.com/ref1.png"
          },
          "role": "reference_image"
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "https://example.com/ref2.png"
          },
          "role": "reference_image"
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "https://example.com/ref3.png"
          },
          "role": "reference_image"
        }
      ]
    }
  }'

6. Pro Model (First Frame Mode)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "doubao-seedance-1-0-pro-250528",
    "metadata": {
      "content": [
        {
          "type": "text",
          "text": "A girl opens her eyes and looks gently at the camera --ratio 16:9 --dur 5 --rs 1080p --wm false"
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "data:image/png;base64,iVBORw0KGgoAAxxxx..."
          }
        }
      ]
    }
  }'

7. Seedance 1.5 Pro Text-to-Video (with Audio)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "doubao-seedance-1-5-pro-251215",
    "metadata": {
      "content": [
        {
          "type": "text",
          "text": "A cute kitten chasing butterflies in a garden, spring sunlight on flowers --ratio 16:9 --dur 6 --rs 720p --wm false"
        }
      ]
    }
  }'

8. Seedance 1.5 Pro Image-to-Video (First Frame Mode, without Audio)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "doubao-seedance-1-5-pro-251215-noAudio",
    "metadata": {
      "content": [
        {
          "type": "text",
          "text": "The scene gradually comes to life, person smiles and looks into the distance --ratio 16:9 --dur 5 --rs 720p --wm false"
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "data:image/png;base64,iVBORw0KGgoAAxxxx..."
          }
        }
      ]
    }
  }'

9. Seedance 1.5 Pro Image-to-Video (First/Last Frame Mode, with Audio)

curl -X POST "https://api.leapx-hub.com/v1/video/generations" \
  -H "Authorization: Bearer sk-xxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "doubao-seedance-1-5-pro-251215",
    "metadata": {
      "content": [
        {
          "type": "text",
          "text": "Smooth transition from static scene to dynamic scene --ratio 16:9 --dur 8 --rs 720p --wm false"
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "data:image/png;base64,iVBORw0KGgoAAxxxx..."
          },
          "role": "first_frame"
        },
        {
          "type": "image_url",
          "image_url": {
            "url": "data:image/png;base64,iVBORw0KGgoAAyyyy..."
          },
          "role": "last_frame"
        }
      ]
    }
  }'

Important Notes (Doubao Seedance Series):

The content array must be placed in the metadata object
All parameters are passed through special markers in the prompt text (e.g. --ratio 16:9)
Images must be placed in the content array using the image_url type
First/last frame mode requires two images, marked with role: "first_frame" and role: "last_frame" respectively
Reference image mode requires using markers like [图1], [图2] in the prompt to reference images, with images marked role: "reference_image"
doubao-seedance-1-0-lite-t2v-250428 does not support image input and adaptive aspect ratio
doubao-seedance-1-0-pro-250528 only supports first frame mode
doubao-seedance-1-5-pro-251215 automatically generates audio, suitable for scenes requiring background music
doubao-seedance-1-5-pro-251215-noAudio does not generate audio, faster rendering, suitable for scenes requiring post-production audio
1.5 pro series supports text-to-video and image-to-video (first frame mode, first/last frame mode), does not support reference image mode
1.5 pro series resolution limit: Only supports 480p and 720p (does not support 1080p)
1.5 pro series duration range: Supports any integer between 4-12 seconds
First/last frame mode: Requires providing two images, marked with role: "first_frame" and role: "last_frame" respectively

Response Example

{
  "task_id": "video_69095b4ce0048190893a01510c0c98b0",
  "status": "submitted",
  "format": "mp4"
}

Query Video Task

Query video generation task status and results

Download Video

Download completed video files (Sora 2 only)

​Introduction

​Authentication

​Request Parameters

​Model-Specific Parameters

​Usage Examples

​Response Example

​Related APIs

Query Video Task

Download Video

Introduction

Authentication

Request Parameters

Model-Specific Parameters

Usage Examples

Response Example

Related APIs