Longcat Avatar 1.5 Multi API Documentation

Longcat Avatar 1.5 Multi API Documentation

Playground

LongCat Avatar 1.5 Multi converts a single image and two audio inputs into multi-character talking or singing videos at up to 720p, capped at 64 seconds per clip. Ready-to-use REST API, no coldstarts, affordable pricing.

Features

What is LongCat Avatar 1.5 Multi?

LongCat Avatar 1.5 Multi animates a single image containing two people from two distinct audio tracks, producing super-realistic, lip-synchronized multi-character video with natural dynamics and identity preserved across frames.

Why it looks great

• Per-speaker lip sync: each speaker’s mouth tracks its own audio precisely.

• Full-body coherence: head motion, facial expressions, and posture align with the assigned audio for each speaker.

• Identity preservation: both faces remain visually consistent throughout the clip.

• Flexible turn-taking: choose between simultaneous speech and ordered turn-taking via the order parameter.

Pricing

> Billing duration: Input media duration is rounded up to whole seconds. The minimum billed duration is 3 seconds; shorter inputs are billed as 3 seconds. Existing per-5-second rate tables remain unchanged.

Billing Rules

• Standard Rate: $0.04 per second
• HD (720p) Rate: $0.08 per second (Double the Standard Rate)
• Minimum Charge: All videos are billed for a minimum of 3 seconds (costing at least $0.12).
• Billing Cap: Billing is capped at 64 seconds.
• order=meanwhile: billed by max(left_audio_duration, right_audio_duration).
• order=left_right / right_left: billed by left_audio_duration + right_audio_duration (both audios played sequentially).

How to Use

1. Upload the left_audio and right_audio files.
2. Upload your image (it should clearly show two people, left and right).
3. Select the speaking order (left_right, right_left, or meanwhile).
4. Select the resolution (480p or 720p).
5. (Optional) Add a prompt to guide expression, style, or pose.
6. Submit the job and download the result once it’s ready.

Note

• Max clip length per job: up to 64 seconds. Longer audio is automatically trimmed.
• Processing speed: approximately 10-30 seconds of wall time per 1 second of video (varies by resolution and queue load).

More Versions

• Single-character version

Related Models

• InfiniteTalk — Higher-end avatar video workflow for more advanced speaking performance.
• InfiniteTalk Multi — Multi-character avatar workflow for more complex scenes.

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'
{
  "image": "https://interactive-examples.mdn.mozilla.net/media/cc0-images/painted-hand-298-332.jpg",
  "left_audio": "https://interactive-examples.mdn.mozilla.net/media/cc0-audio/t-rex-roar.mp3",
  "right_audio": "https://interactive-examples.mdn.mozilla.net/media/cc0-audio/t-rex-roar.mp3",
  "order": "meanwhile",
  "resolution": "480p",
  "seed": -1
}
JSON
)

# 1. Submit the prediction.
SUBMIT_RESPONSE=$(curl --silent --show-error --fail-with-body \
  -X POST "https://api.wavespeed.ai/api/v3/wavespeed-ai/longcat-avatar-1.5/multi" \
  -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