normalize_range_inplace()

MAYAFLUX_API void MayaFlux::Kinesis::Vision::normalize_range_inplace	(	std::span< float >	data,
		float	lo,
		float	hi
	)

Clamp and remap values from [lo, hi] to [0, 1] in-place.

Values outside [lo, hi] are clamped before remapping.

Parameters

data	Float span to remap in-place.
lo	Input range lower bound.
hi	Input range upper bound.

Definition at line 398 of file PixelOps.cpp.

{
    if (lo == hi)
        return;
 
    const float inv = 1.0F / (hi - lo);
    float* out = data.data();
    const size_t n = data.size();
 
#ifdef MAYAFLUX_ARCH_X64
    const __m256 v_lo = _mm256_set1_ps(lo);
    const __m256 v_inv = _mm256_set1_ps(inv);
    const __m256 v_zero = _mm256_setzero_ps();
    const __m256 v_one = _mm256_set1_ps(1.0F);
    size_t i = 0;
    for (; i + 8 <= n; i += 8) {
        __m256 v = _mm256_loadu_ps(out + i);
        v = _mm256_mul_ps(_mm256_sub_ps(v, v_lo), v_inv);
        v = _mm256_min_ps(_mm256_max_ps(v, v_zero), v_one);
        _mm256_storeu_ps(out + i, v);
    }
    for (; i < n; ++i)
        out[i] = std::clamp((out[i] - lo) * inv, 0.0F, 1.0F);
 
#elif defined(MAYAFLUX_ARCH_ARM64)
    const float32x4_t v_lo = vdupq_n_f32(lo);
    const float32x4_t v_inv = vdupq_n_f32(inv);
    const float32x4_t v_zero = vdupq_n_f32(0.0F);
    const float32x4_t v_one = vdupq_n_f32(1.0F);
    size_t i = 0;
    for (; i + 4 <= n; i += 4) {
        float32x4_t v = vld1q_f32(out + i);
        v = vmulq_f32(vsubq_f32(v, v_lo), v_inv);
        v = vminq_f32(vmaxq_f32(v, v_zero), v_one);
        vst1q_f32(out + i, v);
    }
    for (; i < n; ++i)
        out[i] = std::clamp((out[i] - lo) * inv, 0.0F, 1.0F);
 
#else
    P::transform(P::par_unseq, data.begin(), data.end(), data.begin(),
        [lo, inv](float v) { return std::clamp((v - lo) * inv, 0.0F, 1.0F); });
#endif
}

References hi, and lo.