![]() More specifically, for AV1 images, the values of image_width and image_height shall respectively equal the values of FrameWidth and FrameHeight as defined in but for a specific frame in the item payload. The semantics of the ispe property as defined in apply. This property should be marked as essential. Metadata OBUs, if present, shall match the values given in other item properties, such as the PixelInformationProperty or ColourInformationBox. The values of the fields in the AV1CodecConfigurationBox shall match those of the Sequence Header OBU in the AV1 Image Item Data. If a Sequence Header OBU is present in the AV1CodecConfigurationBox, it shall match the Sequence Header OBU in the AV1 Image Item Data. Sequence Header OBUs should not be present in the AV1CodecConfigurationBox. The syntax and semantics of the AV1 Item Configuration Property are identical to those of the AV1CodecConfigurationBox defined in, with the following constraints: Quantity: One for an image item of type 'av01' Mandatory (per item): Yes, for an image item of type 'av01' AV1 Item Configuration Property Box Type: av1C It should have its reduced_still_picture_header flag set to 1. It should have its still_picture flag set to 1. If the AV1 Image Item Data consists of a single frame (i.e. The AV1 Image Item Data shall have exactly one Sequence Header OBU. The AV1 Image Item Data shall be identical to the content of an AV1 Sample marked as sync, as defined in. The content of an AV1 Image Item is called the AV1 Image Item Data and shall obey the following constraints: The AV1 Image Item shall be associated with an AV1 Item Configuration Property. The AV1 Image Item shall be a conformant MIAF image item. ![]() When an item is of type av01, it is called an AV1 Image Item, and shall obey the following constraints: This specification reuses syntax and semantics used in. Specifically, this specification follows the recommendations given in "Annex I: Guidelines On Defining ĪV1 Image File Format also supports multi-layer images as specified in to be stored both in image items and image sequences.Īn AVIF file is designed to be a conformant file for both image items and image sequences. It supports monochrome images as well as multi-channel images with all the bit depths and color spaces specified in. Images encoded with AV1 and not meeting the restrictions of the defined profiles may still be compliant to this AV1 Image File Format if they adhere to the general AVIF requirements.ĪV1 Image File Format supports High Dynamic Range (HDR) and Wide Color Gamut (WCG) images as well as Standard Dynamic Range (SDR). The profiles defined in this specification follow the conventions of the specification. The AV1 Image File Format defines multiple profiles, which restrict the allowed syntax and semantics of the AV1 bitstream with the goal to improve interoperability, especially for hardware implementations. ![]() The AV1 Image File Format (AVIF) defined in this document supports the storage of a subset of the syntax and semantics of an AV1 bitstream in a file. defines the syntax and semantics of an AV1 bitstream. 5.2 AVIF image and image collection brand.5 Brands, Internet media types and file extensions.2.3.2.3 Layered Image Indexing Property.2.3.2.1 Operating Point Selector Property.These constraints are based on constraints defined in the Multi-Image Application Format and are grouped into profiles inspired by the profiles defined in. While defines general requirements, this document also specifies additional constraints to ensure higher interoperability between writers and readers when is used with images. This document specifies syntax and semantics for the storage of images in the generic image file format, which is based on.
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