zenjxl-decoder 0.3.8

High performance Rust implementation of a JPEG XL decoder
Documentation 
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// Copyright (c) the JPEG XL Project Authors. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

#![allow(unused)]
#![allow(clippy::type_complexity)]
#![allow(clippy::erasing_op)]
#![allow(clippy::identity_op)]
use super::*;
use jxl_simd::{F32SimdVec, SimdDescriptor};

#[allow(clippy::too_many_arguments)]
#[allow(clippy::excessive_precision)]
#[inline(always)]
pub(super) fn idct_2<D: SimdDescriptor>(
    d: D,
    mut v0: D::F32Vec,
    mut v1: D::F32Vec,
) -> (D::F32Vec, D::F32Vec) {
    let mut v2 = v0 + v1;
    let mut v3 = v0 - v1;
    (v2, v3)
}

#[inline(always)]
pub(super) fn do_idct_2<D: SimdDescriptor>(
    d: D,
    data: &mut [<D::F32Vec as F32SimdVec>::UnderlyingArray],
    stride: usize,
) {
    assert!(data.len() > 1 * stride);
    let mut v0 = D::F32Vec::load_array(d, &data[0 * stride]);
    let mut v1 = D::F32Vec::load_array(d, &data[1 * stride]);
    (v0, v1) = idct_2(d, v0, v1);
    v0.store_array(&mut data[0 * stride]);
    v1.store_array(&mut data[1 * stride]);
}

#[inline(always)]
pub(super) fn do_idct_2_rowblock<D: SimdDescriptor>(
    d: D,
    data: &mut [<D::F32Vec as F32SimdVec>::UnderlyingArray],
) {
    assert!(data.len() >= 2);
    const { assert!(2usize.is_multiple_of(D::F32Vec::LEN)) };
    let row_stride = 2 / D::F32Vec::LEN;
    let mut v0 = D::F32Vec::load_array(
        d,
        &data[row_stride * (0 % D::F32Vec::LEN) + (0 / D::F32Vec::LEN)],
    );
    let mut v1 = D::F32Vec::load_array(
        d,
        &data[row_stride * (1 % D::F32Vec::LEN) + (1 / D::F32Vec::LEN)],
    );
    (v0, v1) = idct_2(d, v0, v1);
    v0.store_array(&mut data[row_stride * (0 % D::F32Vec::LEN) + (0 / D::F32Vec::LEN)]);
    v1.store_array(&mut data[row_stride * (1 % D::F32Vec::LEN) + (1 / D::F32Vec::LEN)]);
}