Function luma_ac 

pub fn luma_ac<'ac, T: Pixel>(
    ac: &'ac mut [MaybeUninit<i16>],
    ts: &mut TileStateMut<'_, T>,
    tile_bo: TileBlockOffset,
    bsize: BlockSize,
    tx_size: TxSize,
    fi: &FrameInvariants<T>,
) -> &'ac mut [i16]

Returns

Initialized luma AC coefficients

Panics

• If the block size is invalid for subsampling