use crate::convolution::optimisations::Normalizer32;
use crate::pixels::U16;
use crate::{ImageView, ImageViewMut};
#[inline(always)]
pub(crate) fn horiz_convolution(
src_view: &impl ImageView<Pixel = U16>,
dst_view: &mut impl ImageViewMut<Pixel = U16>,
offset: u32,
normalizer: &Normalizer32,
) {
let precision = normalizer.precision();
let coefficients_chunks = normalizer.chunks();
let initial = 1i64 << (precision - 1);
let src_rows = src_view.iter_rows(offset);
let dst_rows = dst_view.iter_rows_mut(0);
for (dst_row, src_row) in dst_rows.zip(src_rows) {
for (coeffs_chunk, dst_pixel) in coefficients_chunks.iter().zip(dst_row.iter_mut()) {
let first_x_src = coeffs_chunk.start as usize;
let mut ss = initial;
let src_pixels = unsafe { src_row.get_unchecked(first_x_src..) };
for (&k, src_pixel) in coeffs_chunk.values().iter().zip(src_pixels) {
ss += src_pixel.0 as i64 * (k as i64);
}
dst_pixel.0 = normalizer.clip(ss);
}
}
}