---
title: Capture Standard
canonical: https://developer.unico.io/dual-api/developers/sdks-and-tools/capture-standard
locale: en
generated_by: markdown-export
---

:::tip[Use the SDKs whenever possible]
For optimal performance of the IDCloud platform's capabilities, we recommend using our SDKs ([Web](/developers/sdks-and-tools/web), [Android](/developers/sdks-and-tools/android/requirements), [iOS](/developers/sdks-and-tools/ios/requirements), [Flutter](/developers/sdks-and-tools/flutter/requirements)). They ensure the best functioning of the product as a whole, both in terms of drop rate and in validating the Liveness.
:::

To achieve better results in image capture, a capture standard has been defined. The image should be clear with sufficient frontal lighting. The face should be straight, facing the camera, free from objects or obstructions, and with a neutral expression.

The most common reasons for capture rejection or low scores are:

- **Lighting behind the client**
- **Overexposed lighting**
- **Face too close to the camera**
- **Blurry images**
- **Shaky images**
- **Client wearing glasses**

## How to obtain a good image capture

The platform follows the **ICAO** standard (International Civil Aviation Organization). The requirements below apply to selfie captures.

### Face positioning

- **Frontal** — the subject looks directly at the camera, head upright, face centered.
- **Shoulders** — aligned and parallel to the camera's image plane.
- **Eyes** — naturally open, pupils and irises visible.
- **Expression** — neutral. No smiling, raised eyebrows, squinting, or frowning.
- **Hair** — must not cover the visible eye area.
- **Coverings** — no glasses, hats, caps, or masks.

### Lighting and background

- **Background** — light, smooth, no texture. No spots, lines, curves, people, furniture, patterns, or plants. Light blue or white work well, provided there is sufficient contrast between the face/hair and the background.
- **Lighting** — adequate and uniform, equally distributed across the face. No shadows behind the face.
- **Brightness and contrast** — good contrast between hair, face, and background.
- **Color** — images must be in color. No grayscale.

### Image formats

Accepted formats: `JPEG`, `PNG`, `JWT`.

## Sizes and proportions

### Selfies

| Property | Value |
|---|---|
| Recommended resolution | 1080×1920 (portrait) or 1920×1080 (landscape) |
| Orientation | Portrait |
| Maximum size | 800 KB (compress to JPEG quality 92 if needed) |

### Documents

| Property | Value |
|---|---|
| Recommended size | HD — 1280×720 or 720×1280 |
| Minimum size | VGA — 640×480 or 480×640 |
| Orientation | If OCR is used, capture in reading orientation |
| Maximum size | 800 KB (compress to JPEG quality 92 if needed) |
| Framing | Avoid excessive empty space around the document. Large unused borders degrade document classification. |

## Examples of standard and non-standard photos

A compliant photo:

- Is in **color** with proper framing.
- Is **sharp and clearly focused**, free of ink marks or creases.

![](/img/capture-standard/image-1.png)

- Shows the subject **looking directly at the camera** with natural skin tone.
- Has appropriate **brightness and contrast**.

![](/img/capture-standard/image-2.png)

- Has a **neutral expression** with eyes clearly visible — no hair covering them.
- Is **face-on**: not over the shoulder, not tilted, both edges of the face visible.
- Has a **simple, light-colored background** — preferably white.
- Has **even lighting** — no shadows, no flash reflections, no red-eye.
- Has **no colored contact lenses** and **no makeup** that significantly alters appearance.

![](/img/capture-standard/image-3.png)

### Glasses

The photo should be captured without glasses. If the subject must wear them:

- Eyes must be **clear** in the photo, with no flash or ambient-light reflections on the lenses.
- Frames must **not cover any part of the eyes**.
- No colored lenses.

![Example of glasses guidance](/img/capture-standard/image-4.png)

:::secondary[Reference]
Image quality guidelines are derived from [ICAO MRTD Photo Guidelines (Annex A)](http://www.icao.int/Security/mrtd/Downloads/TechnicalReports/Annex_A-Photograph_Guidelines.pdf).
:::

## Tips

### Add pre-capture instructions

Show the subject, in plain language, what they need to do before the camera opens — remove glasses, find good lighting, maintain a neutral expression. A short instruction screen drastically reduces retries.

![Example of pre-capture instruction screen](/img/capture-standard/image-5.png)

### Use capture frames

Display a guide overlay that helps the subject position their face or document correctly within the frame.

![Example of capture frame overlay](/img/capture-standard/image-6.png)