๐Ÿฑ meituan-longcat  ยท  Open Source  ยท  MIT License

Audio-Driven Avatar
Video Generation

LongCat-Video-Avatar 1.5 delivers production-ready, commercial-grade avatar synthesis with Whisper-Large lip sync, 8-step distilled inference, and robust long-video generation.

MIT Model Tasks Inference Audio
508
Benchmark Pairs
770
Human Evaluators
6
Application Scenarios
8
Inference Steps (NFE)

Key Features

๐ŸŽ™๏ธ

Whisper-Large Audio Encoder

Replaces Wav2Vec2 with Whisper-Large-v3, yielding significantly smoother and more natural lip dynamics with precise phoneme alignment.

โšก

8-Step DMD2 Distillation

Advanced step distillation accelerates inference to just 8 NFE, balancing cost-effective serving with exceptional visual fidelity.

๐ŸŽญ

Stylized Generalization

Robustly generalizes beyond realistic humans to anime characters, animals, and complex real-world conditions like object handling.

๐Ÿ‘ฅ

Multi-Person Support

Dual-audio modes: Merge mode (parallel streams) or Concatenation mode (sequential speech). Full multi-character video synthesis.

๐Ÿ“น

480P & 720P Resolution

Compatible with both 480P and 720P output, controlled via the --resolution flag. Production-ready super resolution.

๐Ÿ”„

Long-Video Continuation

Multi-segment generation via --num_segments. Maintains full identity consistency and temporal stability across segments.

๐Ÿ’พ

INT8 Quantization

Use --use_int8 to load the INT8 quantized DiT model for significantly reduced VRAM usage (v1.5 only).

๐Ÿ”’

Identity Consistency

Strict identity preservation across frames and segments. Accurate lip-synchronization and full-body temporal stability in long generations.

What You Can Generate

Three native generation modes, all running on the same model checkpoint.

๐Ÿ”Š
--stage_1=at2v

Audio-Text-to-Video

Generate an avatar video from an audio clip + text prompt alone. No reference image needed.

๐Ÿ–ผ๏ธ
--stage_1=ai2v

Audio-Image-to-Video

Animate a reference portrait image with your audio clip. Preserves the exact identity from the image.

๐ŸŽฌ
--num_segments=N

Video Continuation

Generate long-form videos by chaining multiple segments. Maintains temporal coherence and identity.

๐Ÿ‘ฅ
multi_audio_to_video.py

Multi-Person Animation

Animate multiple characters simultaneously with independent or merged audio streams.

Benchmark Results

508 image-audio pairs across 6 scenarios, 2 languages, 2 visual styles. 770 crowdsourced evaluators.

Expert Quality Assessment (4 Dimensions)

Physical Rationality4.6 / 5
Audio-Visual Harmony4.5 / 5
Temporal Stability4.7 / 5
Identity Consistency4.6 / 5

Subjective Human-Likeness (vs Commercial Models)

LongCat-Avatar 1.5 โญ4.4 / 5
Commercial Model A4.1 / 5
Commercial Model B3.8 / 5
Commercial Model C3.6 / 5

Get the Best Results

01

Optimal Audio CFG (3โ€“5)

Audio CFG works best between 3โ€“5. Increase the value for stronger lip synchronization accuracy. Default is 4.

02

Rich, Descriptive Prompts

Longer prompts yield better results. Include character appearance, actions, clothing, and scene context โ€” e.g. "A young woman with long black hair is speaking and smiling, wearing a white blouse, sitting in a bright cafรฉ."

03

Reference Image Index

Set --ref_img_index between 0โ€“24 for best identity consistency. Set to 30 to reduce repeated actions in longer generations.

04

Always Use --use_distill for v1.5

The --use_distill flag is required when using --model_type avatar-v1.5. It enables 8-step DMD2 distillation.

05

Save VRAM with INT8

Add --use_int8 to load the quantized DiT model, significantly reducing VRAM usage without major quality loss (v1.5 only).

Run Locally

Get up and running in a few commands. Requires a GPU with โ‰ฅ16GB VRAM (INT8 mode) or โ‰ฅ24GB VRAM (full).

# Clone the repository git clone --single-branch --branch main https://github.com/meituan-longcat/LongCat-Video cd LongCat-Video # Create conda environment conda create -n longcat-video python=3.10 conda activate longcat-video # Install PyTorch (adjust CUDA version) pip install torch==2.6.0+cu124 torchvision==0.21.0+cu124 torchaudio==2.6.0 \ --index-url https://download.pytorch.org/whl/cu124 # Install Flash Attention 2 pip install ninja psutil packaging flash_attn==2.7.4.post1 # Install all requirements pip install -r requirements.txt conda install -c conda-forge librosa ffmpeg pip install -r requirements_avatar.txt
# Install the HuggingFace CLI pip install "huggingface_hub[cli]" # Download the base model huggingface-cli download meituan-longcat/LongCat-Video \ --local-dir ./weights/LongCat-Video # Download Avatar 1.5 weights huggingface-cli download meituan-longcat/LongCat-Video-Avatar-1.5 \ --local-dir ./weights/LongCat-Video-Avatar-1.5
# Audio-Text-to-Video (AT2V) torchrun --nproc_per_node=2 run_demo_avatar_single_audio_to_video.py \ --context_parallel_size=2 \ --checkpoint_dir=./weights/LongCat-Video-Avatar-1.5 \ --stage_1=at2v \ --input_json=assets/avatar/single_example_1.json \ --use_distill --model_type avatar-v1.5 --use_int8 # Audio-Image-to-Video (AI2V) torchrun --nproc_per_node=2 run_demo_avatar_single_audio_to_video.py \ --context_parallel_size=2 \ --checkpoint_dir=./weights/LongCat-Video-Avatar-1.5 \ --stage_1=ai2v \ --input_json=assets/avatar/single_example_1.json \ --use_distill --model_type avatar-v1.5 --use_int8 # Long video continuation (5 segments) torchrun --nproc_per_node=2 run_demo_avatar_single_audio_to_video.py \ --context_parallel_size=2 \ --checkpoint_dir=./weights/LongCat-Video-Avatar-1.5 \ --stage_1=at2v --num_segments=5 \ --ref_img_index=10 --mask_frame_range=3 \ --use_distill --model_type avatar-v1.5 --use_int8
# Multi-Person Audio-Image-to-Video torchrun --nproc_per_node=2 run_demo_avatar_multi_audio_to_video.py \ --context_parallel_size=2 \ --checkpoint_dir=./weights/LongCat-Video-Avatar-1.5 \ --input_json=assets/avatar/multi_example_1.json \ --use_distill --model_type avatar-v1.5 --use_int8 # Multi-Person with video continuation torchrun --nproc_per_node=2 run_demo_avatar_multi_audio_to_video.py \ --context_parallel_size=2 \ --checkpoint_dir=./weights/LongCat-Video-Avatar-1.5 \ --input_json=assets/avatar/multi_example_1.json \ --num_segments=5 --ref_img_index=10 --mask_frame_range=3 \ --use_distill --model_type avatar-v1.5 --use_int8

โš™๏ธ Hardware Requirements

Component Minimum (INT8) Recommended
GPU VRAM 16 GB 24โ€“40 GB
System RAM 32 GB 64 GB
Disk Storage 50 GB 100 GB
GPU Model A6000 / 3090 A100 80GB
CUDA Version 12.1+ 12.4

Cite This Work

@misc{meituanlongcatteam2025longcatvideoavatar15technicalreport, title={LongCat-Video-Avatar 1.5 Technical Report}, author={Meituan LongCat Team}, year={2026}, archivePrefix={arXiv}, primaryClass={cs.CV}, url={https://huggingface.co/meituan-longcat/LongCat-Video-Avatar-1.5}, }