OPF Image Treatment

Caption Overlay

A compact caption bar attaches attribution, source, or interpretation directly to an image.

caption-overlayNative OPF

Best Fit

Research images, press photos, product screenshots, and data-story evidence slides.

Photography Guidance

Keep the caption outside the subject's focal area. Use captions to clarify provenance or meaning, not to repeat the slide title.

Avoid

Avoid captions that cover faces, product UI, or the main evidence in the image.

Treatment Practices

1

Treat captions as metadata, not primary copy.

2

Use a solid or translucent caption surface with adequate contrast.

3

Keep captions short enough to read in one glance.

OPF Config

image-treatments:caption-overlay
Open Presentation Format
{
  "slide": {
    "layout": "image-focus",
    "elements": [
      {
        "id": "evidence-image",
        "type": "image",
        "src": "https://example.com/evidence.jpg",
        "alt": "Evidence image with source caption",
        "fit": "cover",
        "caption": "Source: field research, 2026",
        "position": {
          "x": 8,
          "y": 12
        },
        "size": {
          "width": 84,
          "height": 72,
          "unit": "%"
        }
      }
    ]
  }
}
Open in OPF Playground

Preview this config live at pptx.dev/playground.

Related How-To Articles

How to Add Images to PowerPoint Slides with pptx.dev

Learn how to embed images in PowerPoint presentations using the pptx.dev API — including cropped, fitted, and multi-image layouts.

How to Place, Size, and Overlay Images in PowerPoint

Master image placement, sizing, cropping, and overlay techniques to create polished, professional presentation slides.

How to Design Image-Focused Full-Bleed Slides in PowerPoint

Use full-bleed photography and imagery to create high-impact presentation slides that command attention.

General Image Rules

1

Crop with intent

Choose fit, position, and size based on the subject and message, not just available space.

2

Protect readability

Text over images needs enough contrast, an intentional overlay, or a separate text surface.

3

Respect image truth

Avoid filters or crops that distort evidence, screenshots, charts, or compliance imagery.

4

Keep a system

Use a small set of image treatments consistently so photo-heavy decks still feel coherent.