diff options
Diffstat (limited to 'alc/uhjfilter.cpp')
| -rw-r--r-- | alc/uhjfilter.cpp | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/alc/uhjfilter.cpp b/alc/uhjfilter.cpp index 99737cc9..c9e35914 100644 --- a/alc/uhjfilter.cpp +++ b/alc/uhjfilter.cpp @@ -47,7 +47,7 @@ std::array<float,Uhj2Encoder::sFilterSize> GenerateFilter() constexpr size_t half_size{32768}; /* Generate a frequency domain impulse with a +90 degree phase offset. Keep - * the latter half clear for converting to the time domain. + * the mirrored frequencies clear for converting to the time domain. */ auto fftBuffer = std::vector<complex_d>(half_size*2, complex_d{}); for(size_t i{0};i < half_size;i += 2) @@ -55,6 +55,7 @@ std::array<float,Uhj2Encoder::sFilterSize> GenerateFilter() fftBuffer[i ] = c0; fftBuffer[i+1] = c1; } + fftBuffer[half_size] = c0; complex_fft(fftBuffer, 1.0); /* Reverse and truncate the filter to a usable size, and store only the @@ -64,7 +65,7 @@ std::array<float,Uhj2Encoder::sFilterSize> GenerateFilter() auto fftiter = fftBuffer.data() + half_size + (Uhj2Encoder::sFilterSize-1); for(float &coeff : ret) { - coeff = static_cast<float>(fftiter->real() / half_size); + coeff = static_cast<float>(fftiter->real() / (half_size+1)); fftiter -= 2; } return ret; @@ -82,6 +83,9 @@ void allpass_process(al::span<float> dst, const float *RESTRICT src) for(size_t i{0};i < todo;i+=4) { const __m128 coeffs{_mm_load_ps(&PShiftCoeffs[i])}; + /* NOTE: This could alternatively be done with two unaligned loads + * and a shuffle. Which would be better? + */ const __m128 s{_mm_setr_ps(src[i*2], src[i*2 + 2], src[i*2 + 4], src[i*2 + 6])}; r4 = _mm_add_ps(r4, _mm_mul_ps(s, coeffs)); } |