in src/convert_image/avx2.rs [1572:1659]
fn i420_rgb<const COLORIMETRY: usize, const DEPTH: usize, const REVERSED: bool>(
width: u32,
height: u32,
_last_src_plane: usize,
src_strides: &[usize],
src_buffers: &[&[u8]],
_last_dst_plane: usize,
dst_strides: &[usize],
dst_buffers: &mut [&mut [u8]],
) -> bool {
// Degenerate case, trivially accept
if width == 0 || height == 0 {
return true;
}
// Check there are sufficient strides and buffers
if src_strides.len() < 3
|| src_buffers.len() < 3
|| dst_strides.is_empty()
|| dst_buffers.is_empty()
{
return false;
}
// Check subsampling limits
let w = width as usize;
let h = height as usize;
let cw = w / 2;
let ch = h / 2;
let rgb_stride = DEPTH * w;
// Compute actual strides
let src_strides = (
compute_stride(src_strides[0], w),
compute_stride(src_strides[1], cw),
compute_stride(src_strides[2], cw),
);
let dst_stride = compute_stride(dst_strides[0], rgb_stride);
// Ensure there is sufficient data in the buffers according
// to the image dimensions and computed strides
let src_buffers = (src_buffers[0], src_buffers[1], src_buffers[2]);
let dst_buffer = &mut *dst_buffers[0];
if out_of_bounds(src_buffers.0.len(), src_strides.0, h - 1, w)
|| out_of_bounds(src_buffers.1.len(), src_strides.1, ch - 1, cw)
|| out_of_bounds(src_buffers.2.len(), src_strides.2, ch - 1, cw)
|| out_of_bounds(dst_buffer.len(), dst_stride, h - 1, rgb_stride)
{
return false;
}
// Process vector part and scalar one
let vector_part = lower_multiple_of_pot(w, YUV_TO_RGB_WAVES);
let scalar_part = w - vector_part;
if vector_part > 0 {
unsafe {
i420_to_bgra_avx2::<COLORIMETRY, REVERSED>(
vector_part,
h,
src_strides,
src_buffers,
dst_stride,
dst_buffer,
);
}
}
if scalar_part > 0 {
let x = vector_part;
let cx = x / 2;
let dx = x * DEPTH;
x86::i420_to_bgra::<COLORIMETRY, REVERSED>(
scalar_part,
h,
src_strides,
(
&src_buffers.0[x..],
&src_buffers.1[cx..],
&src_buffers.2[cx..],
),
dst_stride,
&mut dst_buffer[dx..],
);
}
true
}