MPEG_texture_video

Contributors

• ISO/IEC SC29 WG3 (MPEG Systems) - Scene Description Breakout Group
• Contacts
  • Thomas Stockhammer (MPEG-I Scene Description BoG Chair, tsto@qti.qualcomm.com)

Status

Based on ISO/IEC FDIS 23090-14

Dependencies

Written against the glTF 2.0 spec.

Overview

MPEG_texture_video extension provides the possibility to link a texture object defined in glTF 2.0 to media and its respective track, listed by an MPEG_media. MPEG_texture_video extension also provides a reference to the timed accessor, i.e. accessor with MPEG_accessor_timed extension, where the decoded timed texture will be made available.

When the MPEG_texture_video extension is not supported, a texture buffer should filled by data described by the standard glTF source object.

glTF Schema Updates

MPEG_texture_video Properties

	Type	Description	Required
accessor	integer	Provides the accessor’s index in accessors array	✓ Yes
width	number	Provides the maximum width of the texture.	✓ Yes
height	number	Provides the maximum height of the texture.	✓ Yes
format	string	Indicates the format of the pixel data for this video texture.	No, default: "RGB"
extensions	object	JSON object with extension-specific objects.	No
extras	any	Application-specific data.	No

Additional properties are allowed.

• JSON schema: MPEG_texture_video.schema.json

MPEG_texture_video.accessor

Provides a reference to the accessor, by specifying the accessor’s index in accessors array, that describes the buffer where the decoded timed texture will be made available. The accessor shall have the MPEG_accessor_timed extension. The type, componentType, and count of the accessor depend on the width, height, and format.

• Type: integer
• Required: ✓ Yes
• Minimum: ` >= 0`

MPEG_texture_video.width

Provides the maximum width of the texture.

• Type: number
• Required: ✓ Yes

MPEG_texture_video.height

Provides the maximum height of the texture.

• Type: number
• Required: ✓ Yes

MPEG_texture_video.format

Indicates the format of the pixel data for this video texture. The semantics of these values are defined in Table 8.3 of OpenGL 4.6 specification. The number of components shall match the type indicated by the referenced accessor. Normalization of the pixel data shall be indicated by the normalized attribute of the accessor.

• Type: string
• Required: No, default: "RGB"
• Allowed values:
  • "RED"
  • "GREEN"
  • "BLUE"
  • "RG"
  • "RGB"
  • "RGBA"
  • "BGR"
  • "BGRA"
  • "DEPTH_COMPONENT"

MPEG_texture_video.extensions

JSON object with extension-specific objects.

• Type: object
• Required: No
• Type of each property: Extension

MPEG_texture_video.extras

Application-specific data.

• Type: any
• Required: No

Known Implementations

• ISO/IEC WD 23090-24

Resources

• ISO/IEC FDIS 23090-14, Information technology — Coded representation of immersive media — Part 14: Scene Description
• ISO/IEC WD 23090-24, Information technology — Coded representation of immersive media — Part 24: Conformance and Reference Software for Scene Description for MPEG Media

License

Copyright ISO/IEC 2022

The use of the “MPEG scene description extensions” is subject to the license as accessible here: https://standards.iso.org/ and is subject to the IPR policy as accessible here: https://www.iso.org/iso-standards-and-patents.html.