Struct AppleHdrInfo 

pub struct AppleHdrInfo {
    pub hdr_headroom: Option<f64>,
    pub hdr_gain: f64,
    pub hdr_image_type: Option<i32>,
}

HDR information recovered from an Apple MakerNote.

Fields

hdr_headroom: Option<f64>

0x21 HDRHeadroom (“maker33”). None when the tag is absent — which means there is no Apple HDR gain-map signal at all.

hdr_gain: f64

0x30 HDRGain (“maker48”). Defaults to 0.0 when the tag is absent (Apple omits it on many captures; the formula treats absent as zero).

hdr_image_type: Option<i32>

0x0a HDRImageType: Some(3) = HDR Image, Some(4) = Original/SDR.

Implementations

impl AppleHdrInfo

pub fn headroom_stops(&self) -> Option<f64>

HDR headroom in stops (log2 luminance ratio), or None when no HDRHeadroom (0x21) tag was present.

Piecewise mapping of maker33 (HDRHeadroom) and maker48 (HDRGain), clamped to be non-negative:

if maker33 < 1:  stops = maker48 <= 0.01 ? -20·maker48 + 1.8  : -0.101·maker48 + 1.601
else:            stops = maker48 <= 0.01 ? -70·maker48 + 3.0  : -0.44 ·maker48 + 2.86
stops = max(stops, 0)

pub fn is_hdr(&self) -> bool

Whether HDRImageType marks this as the HDR rendition (3).

pub fn has_gain_map(&self) -> bool

Whether any Apple HDR gain-map signal is present (the 0x21 tag).

Trait Implementations

impl Clone for AppleHdrInfo

fn clone(&self) -> AppleHdrInfo

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for AppleHdrInfo

impl Debug for AppleHdrInfo

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

Formats the value using the given formatter.

impl Default for AppleHdrInfo

fn default() -> AppleHdrInfo

Returns the “default value” for a type.

impl PartialEq for AppleHdrInfo

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for AppleHdrInfo