From 2610abb85fc82056c51c540d7a3d8f691dfe3403 Mon Sep 17 00:00:00 2001 From: Carl Hetherington Date: Wed, 14 Oct 2015 12:38:48 +0100 Subject: [PATCH] Optimise audio filters; tweak order of the LPFs in the upmixers. --- ChangeLog | 5 +++++ src/lib/audio_filter.cc | 37 ++++++++++++++++++++++++++----------- src/lib/audio_filter.h | 8 +++++--- src/lib/upmixer_a.cc | 4 ++-- src/lib/upmixer_b.cc | 2 +- test/audio_filter_test.cc | 3 ++- 6 files changed, 41 insertions(+), 18 deletions(-) diff --git a/ChangeLog b/ChangeLog index e467a0e7c..2b6be5f08 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2015-10-14 Carl Hetherington + + * Various optimizations to the upmixer filters; drop order of + Upmixer A Lfe/C and Upmixer B Lfe filters to speed them up. + 2015-10-13 Carl Hetherington * Version 2.4.11 released. diff --git a/src/lib/audio_filter.cc b/src/lib/audio_filter.cc index 10f3849df..2c92236b6 100644 --- a/src/lib/audio_filter.cc +++ b/src/lib/audio_filter.cc @@ -21,14 +21,14 @@ #include "audio_buffers.h" #include -using std::vector; using std::min; using boost::shared_ptr; -vector +/** @return array of floats which the caller must destroy with delete[] */ +float * AudioFilter::sinc_blackman (float cutoff, bool invert) const { - vector ir (_M + 1); + float* ir = new float[_M + 1]; /* Impulse response */ @@ -66,6 +66,11 @@ AudioFilter::sinc_blackman (float cutoff, bool invert) const return ir; } +AudioFilter::~AudioFilter () +{ + delete[] _ir; +} + shared_ptr AudioFilter::run (shared_ptr in) { @@ -76,18 +81,24 @@ AudioFilter::run (shared_ptr in) _tail->make_silent (); } - for (int i = 0; i < in->channels(); ++i) { - for (int j = 0; j < in->frames(); ++j) { + int const channels = in->channels (); + int const frames = in->frames (); + + for (int i = 0; i < channels; ++i) { + float* tail_p = _tail->data (i); + float* in_p = in->data (i); + float* out_p = out->data (i); + for (int j = 0; j < frames; ++j) { float s = 0; for (int k = 0; k <= _M; ++k) { if ((j - k) < 0) { - s += _tail->data(i)[j - k + _M + 1] * _ir[k]; + s += tail_p[j - k + _M + 1] * _ir[k]; } else { - s += in->data(i)[j - k] * _ir[k]; + s += in_p[j - k] * _ir[k]; } } - out->data(i)[j] = s; + out_p[j] = s; } } @@ -122,14 +133,18 @@ HighPassAudioFilter::HighPassAudioFilter (float transition_bandwidth, float cuto BandPassAudioFilter::BandPassAudioFilter (float transition_bandwidth, float lower, float higher) : AudioFilter (transition_bandwidth) { - vector lpf = sinc_blackman (lower, false); - vector hpf = sinc_blackman (higher, true); + float* lpf = sinc_blackman (lower, false); + float* hpf = sinc_blackman (higher, true); - _ir.resize (_M + 1); + delete[] _ir; + _ir = new float[_M + 1]; for (int i = 0; i <= _M; ++i) { _ir[i] = lpf[i] + hpf[i]; } + delete[] lpf; + delete[] hpf; + /* We now have a band-stop, so invert for band-pass */ for (int i = 0; i <= _M; ++i) { _ir[i] = -_ir[i]; diff --git a/src/lib/audio_filter.h b/src/lib/audio_filter.h index 640e910ca..912e8c210 100644 --- a/src/lib/audio_filter.h +++ b/src/lib/audio_filter.h @@ -21,7 +21,6 @@ #define DCPOMATIC_AUDIO_FILTER_H #include -#include class AudioBuffers; struct audio_filter_impulse_input_test; @@ -30,6 +29,7 @@ class AudioFilter { public: AudioFilter (float transition_bandwidth) + : _ir (0) { _M = 4 / transition_bandwidth; if (_M % 2) { @@ -37,6 +37,8 @@ public: } } + virtual ~AudioFilter (); + boost::shared_ptr run (boost::shared_ptr in); void flush (); @@ -45,9 +47,9 @@ protected: friend struct audio_filter_impulse_kernel_test; friend struct audio_filter_impulse_input_test; - std::vector sinc_blackman (float cutoff, bool invert) const; + float* sinc_blackman (float cutoff, bool invert) const; - std::vector _ir; + float* _ir; int _M; boost::shared_ptr _tail; }; diff --git a/src/lib/upmixer_a.cc b/src/lib/upmixer_a.cc index 3cbb995ef..a01ff30bb 100644 --- a/src/lib/upmixer_a.cc +++ b/src/lib/upmixer_a.cc @@ -31,8 +31,8 @@ using boost::shared_ptr; UpmixerA::UpmixerA (int sampling_rate) : _left (0.02, 1900.0 / sampling_rate, 4800.0 / sampling_rate) , _right (0.02, 1900.0 / sampling_rate, 4800.0 / sampling_rate) - , _centre (0.002, 150.0 / sampling_rate, 1900.0 / sampling_rate) - , _lfe (0.002, 150.0 / sampling_rate) + , _centre (0.01, 150.0 / sampling_rate, 1900.0 / sampling_rate) + , _lfe (0.01, 150.0 / sampling_rate) , _ls (0.02, 4800.0 / sampling_rate, 20000.0 / sampling_rate) , _rs (0.02, 4800.0 / sampling_rate, 20000.0 / sampling_rate) { diff --git a/src/lib/upmixer_b.cc b/src/lib/upmixer_b.cc index 19f0dfed1..9408fdf83 100644 --- a/src/lib/upmixer_b.cc +++ b/src/lib/upmixer_b.cc @@ -29,7 +29,7 @@ using std::vector; using boost::shared_ptr; UpmixerB::UpmixerB (int sampling_rate) - : _lfe (0.002, 150.0 / sampling_rate) + : _lfe (0.01, 150.0 / sampling_rate) , _delay (0.02 * sampling_rate) { diff --git a/test/audio_filter_test.cc b/test/audio_filter_test.cc index c3d799b3b..ebb7df5a0 100644 --- a/test/audio_filter_test.cc +++ b/test/audio_filter_test.cc @@ -55,7 +55,8 @@ audio_filter_impulse_test_one (AudioFilter& f, int block_size, int num_blocks) BOOST_AUTO_TEST_CASE (audio_filter_impulse_kernel_test) { AudioFilter f (0.02); - f._ir.resize (f._M + 1); + delete[] f._ir; + f._ir = new float[f._M + 1]; f._ir[0] = 1; for (int i = 1; i <= f._M; ++i) { -- 2.30.2