Enum GainMapOrigin 

#[non_exhaustive]
pub enum GainMapOrigin {
    AppleAuxItem,
    HeifTmap,
}

Which container mechanism produced the HdrGainMap.

HEIC stores gain maps via either Apple’s iOS 14+ auxiliary item path (XMP metadata, urn:com:apple:photo:2020:aux:hdrgainmap) or the HEIF Amendment 1 / ISO 23008-12:2025 tmap derived image item (ISO 21496-1 binary metadata, the canonical AVIF tmap variant). Consumers branch on this when interpreting the metadata.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

AppleAuxItem

Apple HEIC auxiliary item with the urn:com:apple:photo:2020:aux:hdrgainmap URN. Metadata lives in HdrGainMap::xmp.

HeifTmap

HEIF Amendment 1 tmap derived image item. Metadata lives in HdrGainMap::iso21496 as the AVIF tmap byte payload (per ISO 21496-1, version byte first).

Trait Implementations

impl Clone for GainMapOrigin

fn clone(&self) -> GainMapOrigin

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for GainMapOrigin

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for GainMapOrigin

fn eq(&self, other: &GainMapOrigin) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for GainMapOrigin

impl Eq for GainMapOrigin

impl StructuralPartialEq for GainMapOrigin