Struct lcms2::ToneCurve

pub struct ToneCurve(_);

Tone curves are powerful constructs that can contain curves specified in diverse ways.

The curve is stored in segments, where each segment can be sampled or specified by parameters. A 16.bit simplification of the whole curve is kept for optimization purposes. For float operation, each segment is evaluated separately. Plug-ins may be used to define new parametric schemes.

Owned version of ToneCurveRef

Implementations

impl ToneCurve

pub fn new(gamma: f64) -> Self

Simplified wrapper to new_parametric. Builds a parametric curve of type 1.

pub fn new_tabulated(values: &[u16]) -> Self

Builds a tone curve based on a table of 16-bit values. Tone curves built with this function are restricted to 0…1.0 domain.

pub fn new_tabulated_float(values: &[f32]) -> Self

Builds a tone curve based on a table of floating point values. Tone curves built with this function are not restricted to 0…1.0 domain.

pub fn new_parametric(curve_type: u16, params: &[f64]) -> LCMSResult<Self>

See Table 52 in LCMS documentation for descriptino of the types.

1. Exponential
2. CIE 122-1966
3. IEC 61966-3
4. IEC 61966-2.1 (sRGB)
5. See PDF
6. Identical to 5, unbounded.
7. See PDF
8. See PDF
9. (108) S-Shaped sigmoidal

Always use 10-parameter slice for plug-in types.

Methods from Deref<Target = ToneCurveRef>

pub fn reversed(&self) -> ToneCurve

Creates a tone curve that is the inverse of given tone curve.

pub fn reversed_samples(&self, samples: usize) -> ToneCurve

Creates a tone curve that is the inverse of given tone curve. In the case it couldn’t be analytically reversed, a tablulated curve of nResultSamples is created.

pub fn join(&self, y: &ToneCurveRef, points: usize) -> ToneCurve

Composites two tone curves in the form Y^-1(X(t)) (self is X, the argument is Y)

pub fn is_multisegment(&self) -> bool

Returns TRUE if the tone curve contains more than one segment, FALSE if it has only one segment.

pub fn is_linear(&self) -> bool

Returns an estimation of cube being an identity (1:1) in the [0..1] domain. Does not take unbounded parts into account. This is just a coarse approximation, with no mathematical validity.

pub fn is_monotonic(&self) -> bool

Returns an estimation of monotonicity of curve in the [0..1] domain. Does not take unbounded parts into account. This is just a coarse approximation, with no mathematical validity.

pub fn is_descending(&self) -> bool

Does not take unbounded parts into account.

pub fn parametric_type(&self) -> i32

pub fn estimated_gamma(&self, precision: f64) -> Option<f64>

Estimates the apparent gamma of the tone curve by using least squares fitting. Precision: The maximum standard deviation allowed on the residuals, 0.01 is a fair value, set it to a big number to fit any curve, mo matter how good is the fit.

pub fn smooth(&mut self, lambda: f64) -> bool

Smoothes tone curve according to the lambda parameter. From: Eilers, P.H.C. (1994) Smoothing and interpolation with finite differences. in: Graphic Gems IV, Heckbert, P.S. (ed.), Academic press.

pub fn estimated_entries(&self) -> &[u16]

Tone curves do maintain a shadow low-resolution tabulated representation of the curve. This function returns a pointer to this table.

pub fn eval<ToneCurveValue: FloatOrU16>(
    &self,
    v: ToneCurveValue
) -> ToneCurveValue

Evaluates the given number (u16 or f32) across the given tone curve.

This function is significantly faster for u16, since it uses a pre-computed 16-bit lookup table.

Trait Implementations

impl AsMut<ToneCurveRef> for ToneCurve

fn as_mut(&mut self) -> &mut ToneCurveRef

Performs the conversion.

impl AsRef<ToneCurveRef> for ToneCurve

fn as_ref(&self) -> &ToneCurveRef

Performs the conversion.

impl Borrow<ToneCurveRef> for ToneCurve

fn borrow(&self) -> &ToneCurveRef

Immutably borrows from an owned value.

impl BorrowMut<ToneCurveRef> for ToneCurve

fn borrow_mut(&mut self) -> &mut ToneCurveRef

Mutably borrows from an owned value.

impl Clone for ToneCurve

fn clone(&self) -> ToneCurve

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Deref for ToneCurve

type Target = ToneCurveRef

The resulting type after dereferencing.

fn deref(&self) -> &ToneCurveRef

Dereferences the value.

impl DerefMut for ToneCurve

fn deref_mut(&mut self) -> &mut ToneCurveRef

Mutably dereferences the value.

impl Drop for ToneCurve

fn drop(&mut self)

Executes the destructor for this type.

impl ForeignType for ToneCurve

type CType = ToneCurve

The raw C type.

type Ref = ToneCurveRef

The type representing a reference to this type.

unsafe fn from_ptr(ptr: *mut ToneCurve) -> ToneCurve

Constructs an instance of this type from its raw type.

fn as_ptr(&self) -> *mut ToneCurve

Returns a raw pointer to the wrapped value.