# Image Annotation

Source: https://www.potatoannotator.com/docs/features/image-annotation

Potato supports image annotation for classification, object detection, and region labeling tasks.

## Enabling Image Display

```yaml
image:
  enabled: true
  max_width: 800
  max_height: 600
```

## Data Format

Reference images in your data:

```json
{
  "id": "img_1",
  "image_path": "images/photo_001.jpg",
  "description": "Optional description"
}
```

Configure the image field:

```yaml
data_files:
  - path: data/image_tasks.json
    image_field: image_path
```

## Image Classification

Classify entire images:

```yaml
annotation_schemes:
  - annotation_type: radio
    name: category
    description: "What is shown in this image?"
    labels:
      - Cat
      - Dog
      - Bird
      - Other

  - annotation_type: multiselect
    name: attributes
    description: "Select all that apply"
    labels:
      - Indoor
      - Outdoor
      - Multiple animals
      - Human present
```

## Multi-Label Classification

```yaml
annotation_schemes:
  - annotation_type: multiselect
    name: objects
    description: "What objects are visible?"
    labels:
      - Person
      - Car
      - Building
      - Tree
      - Animal
      - Furniture
      - Food
      - Electronic device
```

## Image Quality Assessment

```yaml
annotation_schemes:
  - annotation_type: likert
    name: quality
    description: "Overall image quality"
    size: 5
    min_label: "Very poor"
    max_label: "Excellent"

  - annotation_type: multiselect
    name: issues
    description: "Select any quality issues"
    labels:
      - Blurry
      - Overexposed
      - Underexposed
      - Noisy
      - Low resolution
      - Watermark visible
```

## Bounding Box Annotation

Draw boxes around objects:

```yaml
annotation_schemes:
  - annotation_type: bbox
    name: objects
    description: "Draw boxes around objects"
    labels:
      - Person
      - Car
      - Bicycle
      - Traffic sign
    label_colors:
      Person: "#3b82f6"
      Car: "#10b981"
      Bicycle: "#f59e0b"
      "Traffic sign": "#ef4444"
```

### Bounding Box Output

```json
{
  "id": "img_1",
  "objects": [
    {
      "label": "Person",
      "x": 100,
      "y": 50,
      "width": 80,
      "height": 200
    },
    {
      "label": "Car",
      "x": 300,
      "y": 150,
      "width": 150,
      "height": 100
    }
  ]
}
```

## Pre-Loaded Bounding Boxes

Load existing annotations for review:

```json
{
  "id": "img_1",
  "image_path": "images/photo_001.jpg",
  "predictions": [
    {"label": "Person", "x": 100, "y": 50, "width": 80, "height": 200, "confidence": 0.95}
  ]
}
```

```yaml
annotation_schemes:
  - annotation_type: bbox
    name: objects
    load_predictions: true
    prediction_field: predictions
```

## Region/Polygon Annotation

For non-rectangular regions:

```yaml
annotation_schemes:
  - annotation_type: polygon
    name: regions
    description: "Outline regions of interest"
    labels:
      - Building
      - Road
      - Vegetation
      - Water
```

## Image Comparison

Compare two images:

```yaml
data_files:
  - path: data/image_pairs.json
    item_a_field: image_original
    item_b_field: image_edited

annotation_schemes:
  - annotation_type: pairwise
    name: preference
    description: "Which image looks better?"
    options:
      - label: "Original"
        value: "A"
      - label: "Edited"
        value: "B"
      - label: "Same"
        value: "tie"
```

## Image Captioning

```yaml
annotation_schemes:
  - annotation_type: text
    name: caption
    description: "Write a caption for this image"
    textarea: true
    placeholder: "Describe what you see..."
    min_length: 10
    max_length: 300
```

## Caption Quality Review

```yaml
data_files:
  - path: data/captions.json
    image_field: image_path
    text_field: generated_caption

annotation_schemes:
  - annotation_type: likert
    name: accuracy
    description: "How accurate is this caption?"
    size: 5
    min_label: "Very inaccurate"
    max_label: "Very accurate"

  - annotation_type: likert
    name: fluency
    description: "How natural is the language?"
    size: 5
    min_label: "Very awkward"
    max_label: "Very natural"

  - annotation_type: text
    name: improved_caption
    description: "Suggest a better caption (optional)"
    textarea: true
```

## Display Options

### Image Sizing

```yaml
image:
  max_width: 800
  max_height: 600
  preserve_aspect_ratio: true
```

### Zoom Controls

```yaml
image:
  zoom_enabled: true
  initial_zoom: fit  # 'fit', 'actual', or percentage
```

### Full-Screen Mode

```yaml
image:
  fullscreen_enabled: true
```

## Content Moderation

```yaml
annotation_schemes:
  - annotation_type: radio
    name: safe_for_work
    description: "Is this image safe for work?"
    labels:
      - Safe
      - Questionable
      - Not Safe

  - annotation_type: multiselect
    name: violation_types
    description: "Select all violations (if any)"
    labels:
      - Violence
      - Adult content
      - Hate symbols
      - Graphic content
      - Spam/advertisement
    show_if:
      scheme: safe_for_work
      value: ["Questionable", "Not Safe"]
```

## Supported Formats

Common image formats supported:
- JPEG/JPG
- PNG
- GIF
- WebP
- BMP

```yaml
image:
  allowed_formats: ["jpg", "jpeg", "png", "webp"]
```

## Full Example: Object Detection Review

```yaml
task_name: "Object Detection Verification"

image:
  enabled: true
  max_width: 1000
  zoom_enabled: true

data_files:
  - path: data/detections.json
    image_field: image_path

annotation_schemes:
  # Review pre-loaded predictions
  - annotation_type: bbox
    name: objects
    description: "Verify and correct object boxes"
    labels:
      - Person
      - Vehicle
      - Animal
      - Object
    load_predictions: true
    prediction_field: model_predictions
    label_colors:
      Person: "#3b82f6"
      Vehicle: "#10b981"
      Animal: "#f59e0b"
      Object: "#6b7280"

  # Overall assessment
  - annotation_type: radio
    name: prediction_quality
    description: "How accurate were the predictions?"
    labels:
      - All correct
      - Minor corrections needed
      - Major corrections needed
      - Mostly incorrect

  - annotation_type: number
    name: missed_objects
    description: "How many objects were missed?"
    min: 0
    max: 50

  - annotation_type: text
    name: notes
    description: "Any issues or comments?"
    textarea: true
    required: false
```

## Performance Tips

1. **Optimize image size** - Resize large images before annotation
2. **Use JPEG for photos** - Smaller file sizes, faster loading
3. **Use PNG for graphics** - Better quality for diagrams/screenshots
4. **Enable lazy loading** - For large datasets
5. **Consider thumbnails** - Show previews in list views
6. **Pre-process consistently** - Normalize sizes and formats