{
  "name": "FastH3 NVFP4 VAE decoder (fast-8L)",
  "format": "fastvideo_h3_decoder_nvfp4_deploy_v1",
  "architecture": "MiniMaxH3VideoViTDecoder3d",
  "decoder_blocks": 8,
  "hidden_size": 2048,
  "nvfp4": {
    "scheme": "W4A4 NVFP4 (E2M1 values, E4M3 per-16 block scales, FP32 per-tensor scale)",
    "block_size": 16,
    "activation_global_scale": "unit",
    "rotation_group": null,
    "quantized_linears": 48,
    "quantized_layers": "transformer_blocks.*.{attn.to_q,attn.to_k,attn.to_v,attn.to_out.0,ff.net.0.proj,ff.net.2}",
    "high_precision": "proj_in, proj_out, norms, register tokens, post_quant_conv"
  },
  "compute_dtype": "bfloat16 autocast",
  "host_vae": "any MiniMax-H3 video VAE with >= 8 decoder blocks (e.g. the 26-block light VAE of the FastH3 V2/Trim stacks); the loader keeps 8",
  "tensor_count_by_dtype": {
    "float32": 89,
    "bfloat16": 96
  },
  "nvfp4_linear_parameters": 537083904,
  "source_step": 5000,
  "files": {
    "decoder.safetensors": {
      "format": "fastvideo_h3_decoder_nvfp4_deploy_v1",
      "contents": "NVFP4 linears as bf16 master weights, packed to NVFP4 at load; other tensors in their trained dtype",
      "bytes": 1099886160,
      "use": "reference weights, re-quantization, further training"
    },
    "decoder-nvfp4.safetensors": {
      "format": "fastvideo_h3_decoder_nvfp4_packed_v1",
      "contents": "pre-packed NVFP4: per linear packed_weight (uint8, two E2M1 codes per byte), weight_inv_scale (E4M3 per-16 block scales, FlashInfer SfLayout.layout_128x4 swizzle), weight_global_sf (fp32), bias (bf16), input_amax (fp32); other tensors in their trained dtype (fp32)",
      "bytes": 328147232,
      "use": "smallest download and lowest load memory; Blackwell only; decodes bit-identically to decoder.safetensors"
    }
  }
}