senior-computer-vision

---
name: "senior-computer-vision"
description: "Computer vision models: object detection, segmentation, training a custom model, and optimizing or deploying inference (YOLO, DETR, SAM, ONNX, TensorRT). Use whenever the user wants to detect objects in images or video, train on their own labeled images, or speed up a slow vision model."
---

# Senior Computer Vision Engineer

Production computer vision engineering skill for object detection, image segmentation, and visual AI system deployment.

## Table of Contents

- [Quick Start](#quick-start)
- [Core Expertise](#core-expertise)
- [Tech Stack](#tech-stack)
- [Workflow 1: Object Detection Pipeline](#workflow-1-object-detection-pipeline)
- [Workflow 2: Model Optimization and Deployment](#workflow-2-model-optimization-and-deployment)
- [Workflow 3: Custom Dataset Preparation](#workflow-3-custom-dataset-preparation)
- [Architecture Selection Guide](#architecture-selection-guide)
- [Reference Documentation](#reference-documentation)

## Quick Start

```bash
# Generate training configuration for YOLO or Faster R-CNN
python scripts/vision_model_trainer.py models/ --task detection --arch yolov8

# Analyze model for optimization opportunities (quantization, pruning)
python scripts/inference_optimizer.py model.pt --target onnx --benchmark

# Build dataset pipeline with augmentations
python scripts/dataset_pipeline_builder.py images/ --format coco --augment
```

## Core Expertise

This skill provides guidance on:

- **Object Detection**: YOLO family (v5-v11), Faster R-CNN, DETR, RT-DETR
- **Instance Segmentation**: Mask R-CNN, YOLACT, SOLOv2
- **Semantic Segmentation**: DeepLabV3+, SegFormer, SAM (Segment Anything)
- **Image Classification**: ResNet, EfficientNet, Vision Transformers (ViT, DeiT)
- **Video Analysis**: Object tracking (ByteTrack, SORT), action recognition
- **3D Vision**: Depth estimation, point cloud processing, NeRF
- **Production Deployment**: ONNX, TensorRT, OpenVINO, CoreML

## Tech Stack

| Category | Technologies |
|----------|--------------|
| Frameworks | PyTorch, torchvision, timm |
| Detection | Ultralytics (YOLO), Detectron2, MMDetection |
| Segmentation | segment-anything, mmsegmentation |
| Optimization | ONNX, TensorRT, OpenVINO, torch.compile |
| Image Processing | OpenCV, Pillow, albumentations |
| Annotation | CVAT, Label Studio, Roboflow |
| Experiment Tracking | MLflow, Weights & Biases |
| Serving | Triton Inference Server, TorchServe |

## Workflow 1: Object Detection Pipeline

Use this workflow when building an object detection system from scratch.

### Step 1: Define Detection Requirements

Analyze the detection task requirements:

```
Detection Requirements Analysis:
- Target objects: [list specific classes to detect]
- Real-time requirement: [yes/no, target FPS]
- Accuracy priority: [speed vs accuracy trade-off]
- Deployment target: [cloud GPU, edge device, mobile]
- Dataset size: [number of images, annotations per class]
```

### Step 2: Select Detection Architecture

Choose architecture based on requirements:

| Requirement | Recommended Architecture | Why |
|-------------|-------------------------|-----|
| Real-time (>30 FPS) | YOLOv8/v11, RT-DETR | Single-stage, optimized for speed |
| High accuracy | Faster R-CNN, DINO | Two-stage, better localization |
| Small objects | YOLO + SAHI, Faster R-CNN + FPN | Multi-scale detection |
| Edge deployment | YOLOv8n, MobileNetV3-SSD | Lightweight architectures |
| Transformer-based | DETR, DINO, RT-DETR | End-to-end, no NMS required |

### Step 3: Prepare Dataset

Convert annotations to required format:

```bash
# COCO format (recommended)
python scripts/dataset_pipeline_builder.py data/images/ \
    --annotations data/labels/ \
    --format coco \
    --split 0.8 0.1 0.1 \
    --output data/coco/

# Verify dataset
python -c "from pycocotools.coco import COCO; coco = COCO('data/coco/train.json'); print(f'Images: {len(coco.imgs)}, Categories: {len(coco.cats)}')"
```

### Step 4: Configure Training

Generate training configuration:

```bash
# For Ultralytics YOLO
python scripts/vision_model_trainer.py data/coco/ \
    --task detection \
    --arch yolov8m \
    --epochs 100 \
    --batch 16 \
    --imgsz 640 \
    --output configs/

# For Detectron2
python scripts/vision_model_trainer.py data/coco/ \
    --task detection \
    --arch faster_rcnn_R_50_FPN \
    --framework detectron2 \
    --output configs/
```

### Step 5: Train and Validate

```bash
# Ultralytics training
yolo detect train data=data.yaml model=yolov8m.pt epochs=100 imgsz=640

# Detectron2 training
python train_net.py --config-file configs/faster_rcnn.yaml --num-gpus 1

# Validate on test set
yolo detect val model=runs/detect/train/weights/best.pt data=data.yaml
```

### Step 6: Evaluate Results

Key metrics to analyze:

| Metric | Target | Description |
|--------|--------|-------------|
| mAP@50 | >0.7 | Mean Average Precision at IoU 0.5 |
| mAP@50:95 | >0.5 | COCO primary metric |
| Precision | >0.8 | Low false positives |
| Recall | >0.8 | Low missed detections |
| Inference time | <33ms | For 30 FPS real-time |

## Workflow 2: Model Optimization and Deployment

Use this workflow when preparing a trained model for production deployment.

### Step 1: Benchmark Baseline Performance

```bash
# Measure current model performance
python scripts/inference_optimizer.py model.pt \
    --benchmark \
    --input-size 640 640 \
    --batch-sizes 1 4 8 16 \
    --warmup 10 \
    --iterations 100
```

Expected output:

```
Baseline Performance (PyTorch FP32):
- Batch 1: 45.2ms (22.1 FPS)
- Batch 4: 89.4ms (44.7 FPS)
- Batch 8: 165.3ms (48.4 FPS)
- Memory: 2.1 GB
- Parameters: 25.9M
```

### Step 2: Select Optimization Strategy

| Deployment Target | Optimization Path |
|-------------------|-------------------|
| NVIDIA GPU (cloud) | PyTorch → ONNX → TensorRT FP16 |
| NVIDIA GPU (edge) | PyTorch → TensorRT INT8 |
| Intel CPU | PyTorch → ONNX → OpenVINO |
| Apple Silicon | PyTorch → CoreML |
| Generic CPU | PyTorch → ONNX Runtime |
| Mobile | PyTorch → TFLite or ONNX Mobile |

### Step 3: Export to ONNX

```bash
# Export with dynamic batch size
python scripts/inference_optimizer.py model.pt \
    --export onnx \
    --input-size 640 640 \
    --dynamic-batch \
    --simplify \
    --output model.onnx

# Verify ONNX model
python -c "import onnx; model = onnx.load('model.onnx'); onnx.checker.check_model(model); print('ONNX model valid')"
```

### Step 4: Apply Quantization (Optional)

For INT8 quantization with calibration:

```bash
# Generate calibration dataset
python scripts/inference_optimizer.py model.onnx \
    --quantize int8 \
    --calibration-data data/calibration/ \
    --calibration-samples 500 \
    --output model_int8.onnx
```

Quantization impact analysis:

| Precision | Size | Speed | Accuracy Drop |
|-----------|------|-------|---------------|
| FP32 | 100% | 1x | 0% |
| FP16 | 50% | 1.5-2x | <0.5% |
| INT8 | 25% | 2-4x | 1-3% |

### Step 5: Convert to Target Runtime

```bash
# TensorRT (NVIDIA GPU)
trtexec --onnx=model.onnx --saveEngine=model.engine --fp16

# OpenVINO (Intel)
mo --input_model model.onnx --output_dir openvino/

# CoreML (Apple)
python -c "import coremltools as ct; model = ct.convert('model.onnx'); model.save('model.mlpackage')"
```

### Step 6: Benchmark Optimized Model

```bash
python scripts/inference_optimizer.py model.engine \
    --benchmark \
    --runtime tensorrt \
    --compare model.pt
```

Expected speedup:

```
Optimization Results:
- Original (PyTorch FP32): 45.2ms
- Optimized (TensorRT FP16): 12.8ms
- Speedup: 3.5x
- Accuracy change: -0.3% mAP
```

## Workflow 3: Custom Dataset Preparation

Use this workflow when preparing a computer vision dataset for training.

### Step 1: Audit Raw Data

```bash
# Analyze image dataset
python scripts/dataset_pipeline_builder.py data/raw/ \
    --analyze \
    --output analysis/
```

Analysis report includes:

```
Dataset Analysis:
- Total images: 5,234
- Image sizes: 640x480 to 4096x3072 (variable)
- Formats: JPEG (4,891), PNG (343)
- Corrupted: 12 files
- Duplicates: 45 pairs

Annotation Analysis:
- Format detected: Pascal VOC XML
- Total annotations: 28,456
- Classes: 5 (car, person, bicycle, dog, cat)
- Distribution: car (12,340), person (8,234), bicycle (3,456), dog (2,890), cat (1,536)
- Empty images: 234
```

### Step 2: Clean and Validate

```bash
# Remove corrupted and duplicate images
python scripts/dataset_pipeline_builder.py data/raw/ \
    --clean \
    --remove-corrupted \
    --remove-duplicates \
    --output data/cleaned/
```

### Step 3: Convert Annotation Format

```bash
# Convert VOC to COCO format
python scripts/dataset_pipeline_builder.py data/cleaned/ \
    --annotations data/annotations/ \
    --input-format voc \
    --output-format coco \
    --output data/coco/
```

Supported format conversions:

| From | To |
|------|-----|
| Pascal VOC XML | COCO JSON |
| YOLO TXT | COCO JSON |
| COCO JSON | YOLO TXT |
| LabelMe JSON | COCO JSON |
| CVAT XML | COCO JSON |

### Step 4: Apply Augmentations

```bash
# Generate augmentation config
python scripts/dataset_pipeline_builder.py data/coco/ \
    --augment \
    --aug-config configs/augmentation.yaml \
    --output data/augmented/
```

Recommended augmentations for detection:

```yaml
# configs/augmentation.yaml
augmentations:
  geometric:
    - horizontal_flip: { p: 0.5 }
    - vertical_flip: { p: 0.1 }  # Only if orientation invariant
    - rotate: { limit: 15, p: 0.3 }
    - scale: { scale_limit: 0.2, p: 0.5 }

  color:
    - brightness_contrast: { brightness_limit: 0.2, contrast_limit: 0.2, p: 0.5 }
    - hue_saturation: { hue_shift_limit: 20, sat_shift_limit: 30, p: 0.3 }
    - blur: { blur_limit: 3, p: 0.1 }

  advanced:
    - mosaic: { p: 0.5 }  # YOLO-style mosaic
    - mixup: { p: 0.1 }   # Image mixing
    - cutout: { num_holes: 8, max_h_size: 32, max_w_size: 32, p: 0.3 }
```

### Step 5: Create Train/Val/Test Splits

```bash
python scripts/dataset_pipeline_builder.py data/augmented/ \
    --split 0.8 0.1 0.1 \
    --stratify \
    --seed 42 \
    --output data/final/
```

Split strategy guidelines:

| Dataset Size | Train | Val | Test |
|--------------|-------|-----|------|
| <1,000 images | 70% | 15% | 15% |
| 1,000-10,000 | 80% | 10% | 10% |
| >10,000 | 90% | 5% | 5% |

### Step 6: Generate Dataset Configuration

```bash
# For Ultralytics YOLO
python scripts/dataset_pipeline_builder.py data/final/ \
    --generate-config yolo \
    --output data.yaml

# For Detectron2
python scripts/dataset_pipeline_builder.py data/final/ \
    --generate-config detectron2 \
    --output detectron2_config.py
```

## Architecture Selection Guide

### Object Detection Architectures

| Architecture | Speed | Accuracy | Best For |
|--------------|-------|----------|----------|
| YOLOv8n | 1.2ms | 37.3 mAP | Edge, mobile, real-time |
| YOLOv8s | 2.1ms | 44.9 mAP | Balanced speed/accuracy |
| YOLOv8m | 4.2ms | 50.2 mAP | General purpose |
| YOLOv8l | 6.8ms | 52.9 mAP | High accuracy |
| YOLOv8x | 10.1ms | 53.9 mAP | Maximum accuracy |
| RT-DETR-L | 5.3ms | 53.0 mAP | Transformer, no NMS |
| Faster R-CNN R50 | 46ms | 40.2 mAP | Two-stage, high quality |
| DINO-4scale | 85ms | 49.0 mAP | SOTA transformer |

### Segmentation Architectures

| Architecture | Type | Speed | Best For |
|--------------|------|-------|----------|
| YOLOv8-seg | Instance | 4.5ms | Real-time instance seg |
| Mask R-CNN | Instance | 67ms | High-quality masks |
| SAM | Promptable | 50ms | Zero-shot segmentation |
| DeepLabV3+ | Semantic | 25ms | Scene parsing |
| SegFormer | Semantic | 15ms | Efficient semantic seg |

### CNN vs Vision Transformer Trade-offs

| Aspect | CNN (YOLO, R-CNN) | ViT (DETR, DINO) |
|--------|-------------------|------------------|
| Training data needed | 1K-10K images | 10K-100K+ images |
| Training time | Fast | Slow (needs more epochs) |
| Inference speed | Faster | Slower |
| Small objects | Good with FPN | Needs multi-scale |
| Global context | Limited | Excellent |
| Positional encoding | Implicit | Explicit |

## Reference Documentation
→ See references/reference-docs-and-commands.md for details

## Performance Targets

| Metric | Real-time | High Accuracy | Edge |
|--------|-----------|---------------|------|
| FPS | >30 | >10 | >15 |
| mAP@50 | >0.6 | >0.8 | >0.5 |
| Latency P99 | <50ms | <150ms | <100ms |
| GPU Memory | <4GB | <8GB | <2GB |
| Model Size | <50MB | <200MB | <20MB |

## Resources

- **Architecture Guide**: `references/computer_vision_architectures.md`
- **Optimization Guide**: `references/object_detection_optimization.md`
- **Deployment Guide**: `references/production_vision_systems.md`
- **Scripts**: `scripts/` directory for automation tools