aom-decode 1.0.0

Minimal safe wrapper for libaom AV1 decoder
Documentation 
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/// A pixel in YUV (YCbCr, `YCgCo`, etc.) planar color space
#[derive(Debug, Copy, Clone, Default, PartialEq, Eq, Hash)]
pub struct YUV<T> {
    /// Luma
    pub y: T,
    /// First chroma channel (Cb)
    pub u: T,
    /// Second chroma channel (Cr)
    pub v: T,
}

/// Iterator that combines equal-sized planes of Y, U, V into YUV pixels
pub fn yuv_444<'a, T: Copy + 'a, YRowsIter, URowsIter, VRowsIter>(y: YRowsIter, u: URowsIter, v: VRowsIter) -> impl Iterator<Item = YUV<T>> + 'a
where
    YRowsIter: Iterator<Item = &'a [T]> + 'a,
    URowsIter: Iterator<Item = &'a [T]> + 'a,
    VRowsIter: Iterator<Item = &'a [T]> + 'a,
{
    y.zip(u.zip(v))
        .flat_map(|(y,(u,v))| {
            y.iter().copied().zip(u.iter().copied().zip(v.iter().copied()))
            .map(|(y,(u,v))| YUV{y,u,v})
        })
}

/// Iterator that combines planes of Y, U, V into YUV pixels, where U and V have half width
///
/// Uses nearest-neighbor scaling.
pub fn yuv_422<'a, T: Copy + 'a, YRowsIter, URowsIter, VRowsIter>(y: YRowsIter, u: URowsIter, v: VRowsIter) -> impl Iterator<Item = YUV<T>> + 'a
where
    YRowsIter: Iterator<Item = &'a [T]> + 'a,
    URowsIter: Iterator<Item = &'a [T]> + 'a,
    VRowsIter: Iterator<Item = &'a [T]> + 'a,
{
    y.zip(u.zip(v))
        .flat_map(|(y,(u,v))| {
            let u = u.iter().copied().flat_map(|u_px| std::iter::repeat_n(u_px, 2));
            let v = v.iter().copied().flat_map(|v_px| std::iter::repeat_n(v_px, 2));
            y.iter().copied().zip(u.zip(v))
            .map(|(y,(u,v))| YUV{y,u,v})
        })
}

/// Iterator that combines planes of Y, U, V into YUV pixels, where U and V have half width and half height
///
/// Uses nearest-neighbor scaling.
pub fn yuv_420<'a, T: Copy + 'a, YRowsIter, URowsIter, VRowsIter>(y: YRowsIter, u: URowsIter, v: VRowsIter) -> impl Iterator<Item = YUV<T>> + 'a
where
    YRowsIter: Iterator<Item = &'a [T]> + 'a,
    URowsIter: Iterator<Item = &'a [T]> + 'a,
    VRowsIter: Iterator<Item = &'a [T]> + 'a,
{
    let u = u.flat_map(|u_row| std::iter::repeat_n(u_row, 2));
    let v = v.flat_map(|v_row| std::iter::repeat_n(v_row, 2));
    y.zip(u.zip(v))
    .flat_map(|(y,(u,v))| {
        let u = u.iter().copied().flat_map(|u_px| std::iter::repeat_n(u_px, 2));
        let v = v.iter().copied().flat_map(|v_px| std::iter::repeat_n(v_px, 2));
        y.iter().copied().zip(u.zip(v))
        .map(|(y,(u,v))| YUV{y,u,v})
    })
}