Core Goals

  1. Model capability retention: Multimodal understanding capability decline not exceeding baseline 3%
  2. Compression efficiency: Model size reduced by 50-75%
  3. Inference speedup: Achieve 2-4x inference speed improvement under typical batch size

Hardware Adaptation Matrix

Hardware TypeRepresentative ModelsQuantization Support Features
Consumer GPURTX 3090/4090INT8/FP16 mixed precision
Server-grade GPUA100/H100FP8 precision format (H100)
Edge deviceJetson OrinINT8 sparse quantization

Candidate Models

Small Models (~3B parameters)

  • Qwen2.5-VL-3B: Suitable for edge device deployment

Medium Models (6B~13B parameters)

  • BLIP-2 (approximately 6B parameters)
  • MiniGPT-4 Vicuna-13B
  • LLaVA-13B

Large Models (70B+ parameters)

  • Qwen2.5-VL-7B/72B
  • OpenFlamingo-9B
  • IDEFICS-80B

Quantization Scheme Comparison

  • PTQ (Post-Training Quantization): GPTQ, SmoothQuant, Q-VLM
  • QAT (Quantization-Aware Training): Compare when resources allow
  • QLoRA: Evaluate performance recovery effect

Mixed Precision Strategies

  • W8A8 (INT8 weights/activations)
  • W8A16 (INT8 weights/FP16 activations)
  • W4A8/W4A16 (INT4 weights)

Key Evaluation Metrics

1. Accuracy Retention

  • VQA accuracy
  • BLEU, CIDEr scores for image caption generation
  • Recall@K for image-text retrieval

2. Model Compression

  • Memory footprint (MB/GB)
  • Compression ratio: 32bit→8bit (4x), 8bit→4bit (2x)

3. Inference Speed

  • Latency (ms) and throughput (samples/sec)
  • Single-stream low latency vs. batch high throughput scenarios

Test Datasets

  • COCO Captions (caption generation)
  • Flickr30k (image-text retrieval)
  • VQA v2 (visual question answering)
  • ActivityNet-QA (video question answering)
  • DocVQA (document question answering)

Quantization Analysis Dimensions

Accuracy vs. Compression Ratio Curve Characteristics

  • FP32→INT8: Accuracy loss typically <1%
  • INT8→INT4: Loss may reach 5-10%

Quantization Robustness Factors

  1. Parameter count: 70B more resistant to quantization than 7B
  2. Attention heads: Multi-head attention has higher redundancy
  3. Activation functions: GELU more tolerant to quantization than ReLU

Recovery Methods Comparison

MethodData VolumeTraining TimeAccuracy Recovery
Pure PTQ00Baseline
QAT (1%)1k samples2 hours+3.2%
QLoRA (5%)5k samples8 hours+5.7%

Expected Milestones

  • Phase 1 (1-2 weeks): ViT-B/16 visual encoder INT8 quantization verification
  • Phase 2 (3-4 weeks): Cross-modal attention layer mixed precision quantization
  • Phase 3 (5-8 weeks): End-to-end inference pipeline optimization