> ## Documentation Index
> Fetch the complete documentation index at: https://docs.jiekou.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# PixVerse C1 First and Last Frame to Video

The PixVerse C1 first-and-last-frame-to-video model generates smooth video transition effects based on a starting frame and an ending frame. It supports multiple resolution and duration configurations, with optional synchronized audio generation.

<Tip>
  This is an **asynchronous** API and only returns the asynchronous task\_id. You should use this task\_id to request the [Get Task Result API](/en/docs/models/reference-get-async-task-result) to retrieve the generated result.
</Tip>

## Request Headers

<ParamField header="Content-Type" type="string" required={true}>
  Enum value: `application/json`
</ParamField>

<ParamField header="Authorization" type="string" required={true}>
  Bearer authentication format: Bearer \{\{API Key}}.
</ParamField>

## Request Body

<ParamField body="image" type="string" required={true}>
  Starting frame image URL
</ParamField>

<ParamField body="prompt" type="string" required={true}>
  Positive prompt text describing the transition effect

  Length limit: 0 - 2048
</ParamField>

<ParamField body="duration" type="integer" default={5}>
  Duration of the generated video (seconds), range 1-15

  Value range: \[1, 15]
</ParamField>

<ParamField body="end_image" type="string" required={true}>
  Ending frame image URL
</ParamField>

<ParamField body="resolution" type="string" default="720p">
  Resolution of the generated video

  Available values: `360p`, `540p`, `720p`, `1080p`
</ParamField>

<ParamField body="generate_audio_switch" type="boolean" default={false}>
  Whether to generate audio at the same time as the video
</ParamField>

## Response Information

<ResponseField name="task_id" type="string" required={true}>
  Use task\_id to request the [Get Task Result API](/en/docs/models/reference-get-async-task-result) to retrieve the generated output.
</ResponseField>