HTML Media Capture

Table of Contents

• 1. Introduction
• 2. Conformance
• 3. Terminology
• 4. Security and privacy considerations
• 5. The capture attribute
  • 5.1 Attributes
• A. Examples
• B. References
  • B.1 Normative references
  • B.2 Informative references

2. Conformance

As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.

The key words must, must not, required, should, should not, recommended, may, and optional in this specification are to be interpreted as described in [RFC2119].

This specification defines conformance criteria that apply to a single product: the user agent that implements the interfaces that it contains.

Implementations that use ECMAScript to implement the APIs defined in this specification must implement them in a manner consistent with the ECMAScript Bindings defined in the Web IDL specification [WEBIDL], as this specification uses that specification and terminology.

3. Terminology

The input element and the HTMLInputElement interface are defined in [HTML5].

The File Upload state is defined in [HTML5].

The enumerated attribute microsyntax, and associated terms and concepts keyword, state, invalid value default, and missing value default, are defined in [HTML5].

In this specification, the term capture control type refers to a specialized type of a file picker control that is optimized, for the user, for capturing media of a specified type.

4. Security and privacy considerations

This specification builds upon the security and privacy protections provided by the <input type="file"> [HTML5] and the [FILE-API] specifications; in particular, it is expected that any offer to start capturing content from the user’s device would require a specific user interaction on an HTML element that is entirely controlled by the user agent.

Implementors should take care of additional leakage of privacy-sensitive data from captured media. For instance, embedding the user’s location in a captured media metadata (e.g. EXIF) might transmit more private data than the user might be expecting.

5. The capture attribute

This section is normative.

When an input element's type attribute is in the File Upload state, the rules in this section apply.

partial interface HTMLInputElement {
    attribute DOMString capture;
};

The capture attribute is used as a hint to the user agent to invoke a file picker of a specific capture control type.

The capture attribute controls the capture state (and associated capture control type) of the element. It is an enumerated attribute. The following table lists the keywords, states, and corresponding capture control types for the attribute. The keywords camera, camcorder, microphone, and filesystem map to the corresponding states: Image Capture, Video Capture, Sound Capture, and File Upload respectively.

The capture attribute's invalid value default and missing value default is the File Upload state.

The HTMLInputElement interface's accept attribute takes precedence over the capture attribute. That is, if the accept attribute's value is set to a MIME type that is not accepted in a defined capture state, the user agent must act as if there was no capture attribute.