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---
base_model:
- meta-models/Muse-Spark-Open-816B-A42B
---

This is a randomly initialized tiny model based on [meta-models/Muse-Spark-Open-816B-A42B](https://huggingface.co/meta-models/Muse-Spark-Open-816B-A42B) for testing and debugging.

| Feature | Source | Tiny |
|---|---|---|
| Checkpoint tensor elements | 821,906,490,368 BF16, 130,039,296 F32 | 3,580,264 BF16, 2,304 F32 |
| Safetensors weight files | 1,644,333,393,864 bytes (65 files) | 7,211,288 bytes (model.safetensors) |
| Text layers / attention cycle | 62 / sliding, full, sliding, sliding | 8 / two source cycles |
| Residual / expert pool / expert intermediate width | 8192 / 4096 / 4096 | 8 / 4 / 16 |
| Q heads / KV heads / head dimension | 128 / 16 / 64 | 8 / 1 / 32 |
| Experts / activated experts | 256 / 8 | 32 / 8 |
| Vocabulary / tying | 202048 / untied | Same |
| Vision layers / width / temporal patch / merge | 50 / 1536 / 2 / 2 | 8 / 32 / 2 / 2 |
| Audio stages / block depths / sample rate | 4 / [2, 2, 2, 2] / 24 kHz | Same |
| Checkpoint precision | BF16; router weights/biases FP32 | Same |
| Modalities | Text + image + video + audio → text | Same |

| File path | Size |
|------|------|
| model.safetensors | 7.2MB |

### Example usage:

- Transformers (✅ verified)

This example uses text, an image, predecoded video frames and a 24 kHz waveform. SDPA remains enabled; batched expert GEMMs support the tiny expert pool without grouped-GEMM alignment padding.

```python
def run_transformers(model_id: str):
    import numpy as np
    import torch
    from PIL import Image
    from transformers import AutoProcessor, MuseSparkForConditionalGeneration
    from transformers.video_utils import VideoMetadata

    processor = AutoProcessor.from_pretrained(model_id)
    model = MuseSparkForConditionalGeneration.from_pretrained(
        model_id,
        dtype=torch.bfloat16,
        attn_implementation="sdpa",
        experts_implementation="batched_mm",
        device_map="cuda",
    )
    image = Image.new("RGB", (112, 112), "blue")
    video = np.stack([np.full((112, 112, 3), value, dtype=np.uint8) for value in (40, 80, 120, 160)])
    audio = (0.1 * np.sin(2 * np.pi * 440 * np.arange(24000) / 24000)).astype(np.float32)
    messages = [
        {
            "role": "user",
            "content": [
                {"type": "image"},
                {"type": "video"},
                {"type": "audio"},
                {"type": "text", "text": "Describe the image, video and sound."},
            ],
        }
    ]
    prompt = processor.apply_chat_template(messages, tokenize=False, add_generation_prompt=True, reasoning_effort="low")
    inputs = processor(
        text=[prompt],
        images=[image],
        videos=[video],
        audio=[audio],
        sampling_rate=24000,
        video_metadata=[VideoMetadata(total_num_frames=4, fps=2, frames_indices=[0, 1, 2, 3])],
        do_sample_frames=False,
        return_tensors="pt",
    ).to(model.device, dtype=model.dtype)
    outputs = model.generate(**inputs, max_new_tokens=10, do_sample=False)
    print(model)
    print(processor.batch_decode(outputs[:, inputs.input_ids.shape[1] :], skip_special_tokens=True))


if __name__ == "__main__":
    run_transformers(model_id="tiny-random/muse-spark-open")
```

- SGLang (✅ verified)

Muse Spark's BF16 experts require EP=TP, so this single-node launch uses TP=4 and EP=4. Install FFmpeg shared libraries for video decoding.

```bash
sglang serve \
  --model-path tiny-random/muse-spark-open \
  --tp-size 4 \
  --ep-size 4 \
  --attention-backend triton \
  --context-length 4096 \
  --max-running-requests 4 \
  --max-total-tokens 4096 \
  --mem-fraction-static 0.2 \
  --disable-custom-all-reduce
```

### Codes to create this repo:

<details><summary>Click to expand</summary>

```python
def create_model(source_model_id: str, source_revision: str, save_folder: str) -> str:
    import json
    from pathlib import Path
    import torch
    from huggingface_hub import hf_hub_download
    from transformers import MuseSparkConfig, MuseSparkForConditionalGeneration, set_seed

    folder = Path(save_folder)
    folder.mkdir(parents=True, exist_ok=True)
    config_json = json.loads(
        Path(hf_hub_download(source_model_id, "config.json", revision=source_revision)).read_text()
    )
    text = config_json["text_config"]
    text.update(
        hidden_size=8,
        num_attention_heads=8,
        num_key_value_heads=1,
        head_dim=32,
        num_hidden_layers=8,
        intermediate_size=32,
        moe_hidden_size=4,
        moe_intermediate_size=16,
        num_local_experts=32,
    )
    for name in ("layer_types", "mlp_layer_types", "layer_rope_theta"):
        text[name] = text[name][:8]
    vision = config_json["vision_config"]
    vision.update(hidden_size=32, intermediate_size=64, num_attention_heads=4, num_hidden_layers=8)
    vision["layer_types"] = vision["layer_types"][:8]
    config_json["audio_config"].update(hidden_sizes=[8, 16, 32, 64], out_hidden_size=8)
    config_json.update(out_hidden_size=128, projector_hidden_size=16)
    config = MuseSparkConfig.from_dict(config_json)
    set_seed(42)
    model = MuseSparkForConditionalGeneration._from_config(config, dtype=torch.bfloat16, attn_implementation="sdpa")
    # The source checkpoint uses FP32 only for routed-expert router weights and
    # correction biases; residual gates and all other parameters remain BF16.
    for module in model.modules():
        if module.__class__.__name__ == "MuseSparkTopkRouter":
            module.float()
    model.save_pretrained(folder, safe_serialization=True)
    # Restore the deliberately edited raw config and immutable shared assets.
    (folder / "config.json").write_text(json.dumps(config_json, indent=2) + "\n")
    for name in (
        "tokenizer.json",
        "tokenizer_config.json",
        "special_tokens_map.json",
        "chat_template.jinja",
        "processor_config.json",
        "generation_config.json",
        "l4_200k_base",
        "LICENSE.md",
        "USE_POLICY.md",
    ):
        (folder / name).write_bytes(Path(hf_hub_download(source_model_id, name, revision=source_revision)).read_bytes())
    return str(model)


create_model(
    source_model_id="meta-models/Muse-Spark-Open-816B-A42B",
    source_revision="0fb02478b02565b2ce7fc57e6051c91172774ac9",
    save_folder="/tmp/muse-spark-open",
)
```

</details>

### Printing the model:

<details><summary>Click to expand</summary>

```text
MuseSparkForConditionalGeneration(
  (model): MuseSparkModel(
    (vision_tower): MuseSparkVisionModel(
      (patch_embedder): MuseSparkVisionPatchEmbedder(
        (patch_embedding): Linear(in_features=1176, out_features=32, bias=False)
        (position_embedding_table): Embedding(1024, 32)
      )
      (rotary_emb): MuseSparkVisionRotaryEmbedding()
      (ln_pre): LayerNorm((32,), eps=1e-05, elementwise_affine=True, bias=True)
      (layers): ModuleList(
        (0-7): 8 x MuseSparkVisionEncoderLayer(
          (norm1): LayerNorm((32,), eps=1e-05, elementwise_affine=True, bias=True)
          (norm2): LayerNorm((32,), eps=1e-05, elementwise_affine=True, bias=True)
          (attn): MuseSparkVisionAttention(
            (proj): Linear(in_features=32, out_features=32, bias=True)
            (q_proj): Linear(in_features=32, out_features=32, bias=True)
            (k_proj): Linear(in_features=32, out_features=32, bias=True)
            (v_proj): Linear(in_features=32, out_features=32, bias=True)
          )
          (mlp): MuseSparkVisionMLP(
            (fc1): Linear(in_features=32, out_features=64, bias=True)
            (act): GELUActivation()
            (fc2): Linear(in_features=64, out_features=32, bias=True)
          )
        )
      )
      (ln_post): LayerNorm((32,), eps=1e-05, elementwise_affine=True, bias=True)
    )
    (language_model): MuseSparkTextModel(
      (embed_tokens): MuseSparkTextNormedEmbedding(
        202048, 8, padding_idx=200018
        (embed_norm): MuseSparkRMSNorm()
      )
      (layers): ModuleList(
        (0-7): 8 x MuseSparkTextDecoderLayer(
          (self_attn): MuseSparkTextAttention(
            (q_proj): Linear(in_features=8, out_features=256, bias=False)
            (k_proj): Linear(in_features=8, out_features=32, bias=False)
            (v_proj): Linear(in_features=8, out_features=32, bias=False)
            (o_proj): Linear(in_features=256, out_features=8, bias=False)
            (gate_proj): Linear(in_features=8, out_features=256, bias=False)
            (qk_norm): MuseSparkRMSNorm()
            (o_norm): MuseSparkRMSNorm()
          )
          (mlp): MuseSparkMoE(
            (gate): MuseSparkTopkRouter(
              (scoring_function): Sigmoid()
            )
            (pre_expert_proj): Linear(in_features=8, out_features=4, bias=False)
            (pre_expert_norm): MuseSparkTextCenteredRMSNorm((4,), eps=1e-05)
            (experts): MuseSparkExperts(
              (act_fn): SiLUActivation()
              (post_expert_norm): MuseSparkTextInputScaledRMSNorm((4,), eps=1e-08)
            )
            (post_expert_proj): Linear(in_features=4, out_features=8, bias=False)
          )
          (input_layernorm): MuseSparkTextCenteredRMSNorm((8,), eps=1e-05)
          (post_attention_layernorm): MuseSparkRMSNorm()
          (pre_feedforward_layernorm): MuseSparkTextCenteredRMSNorm((8,), eps=1e-05)
          (post_feedforward_layernorm): MuseSparkTextInputScaledRMSNorm((8,), eps=1e-08)
          (post_attention_residual_gate): MuseSparkResidualGate()
          (post_feedforward_residual_gate): MuseSparkResidualGate()
        )
      )
      (norm): MuseSparkRMSNorm()
      (rotary_emb): MuseSparkTextRotaryEmbedding()
    )
    (vision_adapter): MuseSparkVisionAdapter(
      (fc1): Linear(in_features=128, out_features=16, bias=False)
      (act): GELUActivation()
      (fc2): Linear(in_features=16, out_features=16, bias=False)
    )
    (vision_projection): Linear(in_features=16, out_features=8, bias=False)
    (perception_emb_norm): MuseSparkRMSNorm()
    (audio_tower): MuseSparkAudioModel(
      (layers): ModuleList(
        (0): MuseSparkAudioLayer(
          (patch_embedder): MuseSparkAudioPatchEmbedding(
            (proj): Linear(in_features=16, out_features=8, bias=True)
            (norm): MuseSparkRMSNorm()
          )
          (conv_blocks): ModuleList(
            (0-1): 2 x MuseSparkAudioConvBlock(
              (conv): MuseSparkAudioCausalConv1d(8, 8, kernel_size=(7,), stride=(1,), groups=8)
              (norm): MuseSparkRMSNorm()
              (mlp): MuseSparkAudioMLP(
                (fc1): Linear(in_features=8, out_features=32, bias=True)
                (fc2): Linear(in_features=32, out_features=8, bias=True)
                (activation_fn): GELUActivation()
              )
            )
          )
        )
        (1): MuseSparkAudioLayer(
          (patch_embedder): MuseSparkAudioPatchEmbedding(
            (proj): Linear(in_features=48, out_features=16, bias=True)
            (norm): MuseSparkRMSNorm()
          )
          (conv_blocks): ModuleList(
            (0-1): 2 x MuseSparkAudioConvBlock(
              (conv): MuseSparkAudioCausalConv1d(16, 16, kernel_size=(7,), stride=(1,), groups=16)
              (norm): MuseSparkRMSNorm()
              (mlp): MuseSparkAudioMLP(
                (fc1): Linear(in_features=16, out_features=64, bias=True)
                (fc2): Linear(in_features=64, out_features=16, bias=True)
                (activation_fn): GELUActivation()
              )
            )
          )
        )
        (2): MuseSparkAudioLayer(
          (patch_embedder): MuseSparkAudioPatchEmbedding(
            (proj): Linear(in_features=80, out_features=32, bias=True)
            (norm): MuseSparkRMSNorm()
          )
          (conv_blocks): ModuleList(
            (0-1): 2 x MuseSparkAudioConvBlock(
              (conv): MuseSparkAudioCausalConv1d(32, 32, kernel_size=(7,), stride=(1,), groups=32)
              (norm): MuseSparkRMSNorm()
              (mlp): MuseSparkAudioMLP(
                (fc1): Linear(in_features=32, out_features=128, bias=True)
                (fc2): Linear(in_features=128, out_features=32, bias=True)
                (activation_fn): GELUActivation()
              )
            )
          )
        )
        (3): MuseSparkAudioLayer(
          (patch_embedder): MuseSparkAudioPatchEmbedding(
            (proj): Linear(in_features=128, out_features=64, bias=True)
            (norm): MuseSparkRMSNorm()
          )
          (conv_blocks): ModuleList(
            (0-1): 2 x MuseSparkAudioConvBlock(
              (conv): MuseSparkAudioCausalConv1d(64, 64, kernel_size=(7,), stride=(1,), groups=64)
              (norm): MuseSparkRMSNorm()
              (mlp): MuseSparkAudioMLP(
                (fc1): Linear(in_features=64, out_features=256, bias=True)
                (fc2): Linear(in_features=256, out_features=64, bias=True)
                (activation_fn): GELUActivation()
              )
            )
          )
        )
      )
      (norm): MuseSparkRMSNorm()
      (proj): Linear(in_features=64, out_features=8, bias=True)
      (post_proj_norm): MuseSparkRMSNorm()
    )
  )
  (lm_head): Linear(in_features=8, out_features=202048, bias=False)
)
```

</details>

Environment: [.meta.json](.meta.json)

### Change log:

- 2026-10-26: Created a tiny Muse Spark Open checkpoint preserving text, image, video and audio inputs.

This repo is generated by GPT-6.1-Sol