Optimise audio filters; tweak order of the LPFs in the upmixers.

diff --git a/ChangeLog b/ChangeLog
index e467a0e7c93340773c0c7ce5d4cfd19416c41181..2b6be5f0864f1c9f773c94c0128bbbd6540d7e71 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2015-10-14  Carl Hetherington  <cth@carlh.net>
+
+       * 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  <cth@carlh.net>
 
        * Version 2.4.11 released.

diff --git a/src/lib/audio_filter.cc b/src/lib/audio_filter.cc
index 10f3849dffa3aa271b9521b14c4af24d9f1533e0..2c92236b6f55fe1b2a0c4ffd3bab3afaad30f5bb 100644 (file)
--- a/src/lib/audio_filter.cc
+++ b/src/lib/audio_filter.cc
@@ -21,14 +21,14 @@
 #include "audio_buffers.h"
 #include <cmath>
 
-using std::vector;
 using std::min;
 using boost::shared_ptr;
 
-vector<float>
+/** @return array of floats which the caller must destroy with delete[] */
+float *
 AudioFilter::sinc_blackman (float cutoff, bool invert) const
 {
-       vector<float> 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<AudioBuffers>
 AudioFilter::run (shared_ptr<const AudioBuffers> in)
 {
@@ -76,18 +81,24 @@ AudioFilter::run (shared_ptr<const AudioBuffers> 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<float> lpf = sinc_blackman (lower, false);
-       vector<float> 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 640e910ca83445ff970d7fe3a766385c6c98ea02..912e8c210d3ad9b9129df6f308108ba6b2069a56 100644 (file)
--- a/src/lib/audio_filter.h
+++ b/src/lib/audio_filter.h
@@ -21,7 +21,6 @@
 #define DCPOMATIC_AUDIO_FILTER_H
 
 #include <boost/shared_ptr.hpp>
-#include <vector>
 
 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<AudioBuffers> run (boost::shared_ptr<const AudioBuffers> in);
 
        void flush ();
@@ -45,9 +47,9 @@ protected:
        friend struct audio_filter_impulse_kernel_test;
        friend struct audio_filter_impulse_input_test;
 
-       std::vector<float> sinc_blackman (float cutoff, bool invert) const;
+       float* sinc_blackman (float cutoff, bool invert) const;
 
-       std::vector<float> _ir;
+       float* _ir;
        int _M;
        boost::shared_ptr<AudioBuffers> _tail;
 };

diff --git a/src/lib/upmixer_a.cc b/src/lib/upmixer_a.cc
index 3cbb995efc13d8ca494be776cdad49a989bddc56..a01ff30bb40f39dfbd2e6199e152a1513de6d549 100644 (file)
--- 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 19f0dfed143ed5f1acd47e8589e61ad58b9dbe06..9408fdf83fa10b2046e77a4afb59720568ea225f 100644 (file)
--- 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 c3d799b3bdd71c1afb7bd6bf261ec3582b61a5b3..ebb7df5a0f64e4f90cae97ccdbe8d1d4856f70f0 100644 (file)
--- 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) {