yuv 0.1.10

Basic conversion between various YUV (YCbCr) formats and RGB
Documentation 
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use crate::depth::{Bounded, Depth, Depth10, Depth12, Depth16, Depth8};
use num_traits::PrimInt;

pub(crate) trait Range: 'static {
    type Pixel: Bounded + PrimInt;

    const Y_MIN: Self::Pixel;
    const Y_MAX: Self::Pixel;
    const UV_MIN: Self::Pixel;
    const UV_MAX: Self::Pixel;
}

/// Full numeric range (no rescaling needed)
pub(crate) struct Full<D>(pub D);

/// TV/Studio range
pub(crate) struct Limited<D>(pub D);

impl<D: Depth> Range for Full<D> {
    type Pixel = D::Pixel;

    const Y_MIN: D::Pixel = D::Pixel::MIN;
    const Y_MAX: D::Pixel = D::MAX;
    const UV_MIN: D::Pixel = D::Pixel::MIN;
    const UV_MAX: D::Pixel = D::MAX;
}

impl Range for Limited<Depth8> {
    type Pixel = u8;

    const Y_MIN: u8 = 16;
    const Y_MAX: u8 = 235;
    const UV_MIN: u8 = 16;
    const UV_MAX: u8 = 240;
}

impl Range for Limited<Depth10> {
    type Pixel = u16;

    const Y_MIN: u16 = 64;
    const Y_MAX: u16 = 940;
    const UV_MIN: u16 = 64;
    const UV_MAX: u16 = 960;
}

impl Range for Limited<Depth12> {
    type Pixel = u16;

    const Y_MIN: u16 = 256;
    const Y_MAX: u16 = 3760;
    const UV_MIN: u16 = 256;
    const UV_MAX: u16 = 3840;
}

impl Range for Limited<Depth16> {
    type Pixel = u16;

    const Y_MIN: u16 = 4112;
    const Y_MAX: u16 = 60395;
    const UV_MIN: u16 = 4112;
    const UV_MAX: u16 = 61680;
}

#[derive(Debug, Copy, Clone)]
pub(crate) struct RangeScale {
    /// First, multiply by this
    pub mul: f32,
    /// Then subtract this
    pub sub: f32,
}

#[inline(always)]
pub(crate) fn to_floats<F: Range>(multiply: f64) -> (RangeScale, RangeScale) where F::Pixel: Into<f64> {
    let y_min = F::Y_MIN.into();
    let y_max = F::Y_MAX.into();
    let y = RangeScale {
        mul: (multiply / (y_max - y_min)) as f32,
        sub: (multiply * y_min / (y_max - y_min)) as f32,
    };
    let uv_min = F::UV_MIN.into();
    let uv_max = F::UV_MAX.into();
    let uv = RangeScale {
        mul: (multiply / (uv_max - uv_min)) as f32,
        sub: (multiply * (if uv_min == 0. {
            (uv_max/2.).ceil() / uv_max
        } else {
            uv_min / (uv_max - uv_min) + 0.5
        })) as f32,
    };
    (y, uv)
}