scrfd_320_batched_64

InsightFace Batch-Optimized Models (Max Batch 64)

Re-exported InsightFace models with proper dynamic batch support and no cross-frame contamination.

⚠️ Version Difference

Recommendation: Use max batch=32 for optimal performance. Batch=64 provides similar throughput but uses more VRAM.

Why These Models?

The original InsightFace ONNX models have issues with batch inference:

• buffalo_l detection model: hardcoded batch=1
• buffalo_l_batch detection model: broken - has cross-frame contamination due to reshape operations that flatten the batch dimension

These re-exports fix the dynamic_axes in the ONNX graph for true batch inference.

Models

Performance (TensorRT FP16, RTX 5090)

Batch Size Comparison (Full Video, 12,263 frames)

Key Finding: Batch=32 is optimal. Batch=64 provides no additional benefit due to GPU memory bandwidth saturation.

With Pipelined Preprocessing (4 workers)

Usage

import numpy as np
import onnxruntime as ort

# Load model
sess = ort.InferenceSession("scrfd_10g_320_batch64.onnx", 
                            providers=["TensorrtExecutionProvider", "CUDAExecutionProvider"])

# Batch inference (any size from 1-64)
batch = np.random.randn(32, 3, 320, 320).astype(np.float32)
outputs = sess.run(None, {"input.1": batch})

# outputs[0-2]: scores per FPN level (stride 8, 16, 32)
# outputs[3-5]: bboxes per FPN level
# outputs[6-8]: keypoints per FPN level

TensorRT Configuration

When using TensorRT, set profile shapes to support your desired batch range:

providers = [
    ("TensorrtExecutionProvider", {
        "trt_fp16_enable": True,
        "trt_engine_cache_enable": True,
        "trt_profile_min_shapes": "input.1:1x3x320x320",
        "trt_profile_opt_shapes": "input.1:32x3x320x320",  # Optimize for batch=32
        "trt_profile_max_shapes": "input.1:64x3x320x320",  # Support up to 64
    }),
    "CUDAExecutionProvider",
]

Verified: No Batch Contamination

# Same frame processed alone vs in batch = identical results
single_output = sess.run(None, {"input.1": frame[np.newaxis, ...]})
batch[7] = frame
batch_output = sess.run(None, {"input.1": batch})

max_diff = np.max(np.abs(single_output[0] - batch_output[0][7]))
# max_diff < 1e-5 ✓

Re-export Process

These models were re-exported from InsightFace's PyTorch source using MMDetection with proper dynamic_axes:

dynamic_axes = {
    "input.1": {0: "batch"},
    "score_8": {0: "batch"},
    "score_16": {0: "batch"},
    # ... all outputs
}

License

Non-commercial research purposes only - per InsightFace license.

For commercial licensing, contact: [email protected]

Credits

• Original models: InsightFace by Jia Guo et al.
• SCRFD paper: Sample and Computation Redistribution for Efficient Face Detection
• ArcFace paper: ArcFace: Additive Angular Margin Loss for Deep Face Recognition