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author | Eric Laurent <elaurent@google.com> | 2010-07-09 12:28:50 -0700 |
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committer | Eric Laurent <elaurent@google.com> | 2010-07-17 06:33:00 -0700 |
commit | 2c8e5cab3faa6d360e222b7a6c40a80083d021ac (patch) | |
tree | fd19b8baa829edb78116b089d1122ea4ef0921e1 /media/libeffects/testlibs/AudioShelvingFilter.cpp | |
parent | ada2ac8e09b6d3f2b3c3155a852ba0fffae1b592 (diff) | |
download | frameworks_av-2c8e5cab3faa6d360e222b7a6c40a80083d021ac.zip frameworks_av-2c8e5cab3faa6d360e222b7a6c40a80083d021ac.tar.gz frameworks_av-2c8e5cab3faa6d360e222b7a6c40a80083d021ac.tar.bz2 |
First submission of audio effect library from NXP software.
This CL contains the first open sourceable version of the audio effect library from NXP software.
The effects implemented are:
- Bass boost
- Virtualizer (stereo widening)
- Equalizer
- Spectrum analyzer
Source file for the effect engines are located under libeffects/lvm/lib
The wrapper implementing the interface with the audio effect framework in under libeffects/lvm/wrapper
The code of other effect libraries has also been reorganized fo clarity:
- the effect factory is now under libeffects/factory
- the test equalizer and reverb effects are under libeffect/testlibs
- the visualizer is under libeffects/virtualizer
Change-Id: I8d91e2181f81b89f8fc0c1e1e6bf552c5809b2eb
Diffstat (limited to 'media/libeffects/testlibs/AudioShelvingFilter.cpp')
-rw-r--r-- | media/libeffects/testlibs/AudioShelvingFilter.cpp | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/media/libeffects/testlibs/AudioShelvingFilter.cpp b/media/libeffects/testlibs/AudioShelvingFilter.cpp new file mode 100644 index 0000000..b8650ba --- /dev/null +++ b/media/libeffects/testlibs/AudioShelvingFilter.cpp @@ -0,0 +1,109 @@ +/* /android/src/frameworks/base/libs/audioflinger/AudioShelvingFilter.cpp +** +** Copyright 2009, The Android Open Source Project +** +** Licensed under the Apache License, Version 2.0 (the "License"); +** you may not use this file except in compliance with the License. +** You may obtain a copy of the License at +** +** http://www.apache.org/licenses/LICENSE-2.0 +** +** Unless required by applicable law or agreed to in writing, software +** distributed under the License is distributed on an "AS IS" BASIS, +** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +** See the License for the specific language governing permissions and +** limitations under the License. +*/ + +#include "AudioShelvingFilter.h" +#include "AudioCommon.h" +#include "EffectsMath.h" + +#include <new> +#include <assert.h> + +#define LIKELY( exp ) (__builtin_expect( (exp) != 0, true )) +#define UNLIKELY( exp ) (__builtin_expect( (exp) != 0, false )) + +namespace android { +// Format of the coefficient tables: +// kCoefTable[freq][gain][coef] +// freq - cutoff frequency, in octaves below Nyquist,from -10 to -6 in low +// shelf, -2 to 0 in high shelf. +// gain - gain, in millibel, starting at -9600, jumps of 1024, to 4736 millibel. +// coef - 0: b0 +// 1: b1 +// 2: b2 +// 3: -a1 +// 4: -a2 +static const size_t kHiInDims[2] = {3, 15}; +static const audio_coef_t kHiCoefTable[3*15*5] = { +#include "AudioHighShelfFilterCoef.inl" +}; +static const size_t kLoInDims[2] = {5, 15}; +static const audio_coef_t kLoCoefTable[5*15*5] = { +#include "AudioLowShelfFilterCoef.inl" +}; + +AudioCoefInterpolator AudioShelvingFilter::mHiCoefInterp(2, kHiInDims, 5, (const audio_coef_t*) kHiCoefTable); +AudioCoefInterpolator AudioShelvingFilter::mLoCoefInterp(2, kLoInDims, 5, (const audio_coef_t*) kLoCoefTable); + +AudioShelvingFilter::AudioShelvingFilter(ShelfType type, int nChannels, + int sampleRate) + : mType(type), + mBiquad(nChannels, sampleRate) { + configure(nChannels, sampleRate); +} + +void AudioShelvingFilter::configure(int nChannels, int sampleRate) { + mNiquistFreq = sampleRate * 500; + mFrequencyFactor = ((1ull) << 42) / mNiquistFreq; + mBiquad.configure(nChannels, sampleRate); + setFrequency(mNominalFrequency); + commit(true); +} + +void AudioShelvingFilter::reset() { + setGain(0); + setFrequency(mType == kLowShelf ? 0 : mNiquistFreq); + commit(true); +} + +void AudioShelvingFilter::setFrequency(uint32_t millihertz) { + mNominalFrequency = millihertz; + if (UNLIKELY(millihertz > mNiquistFreq / 2)) { + millihertz = mNiquistFreq / 2; + } + uint32_t normFreq = static_cast<uint32_t>( + (static_cast<uint64_t>(millihertz) * mFrequencyFactor) >> 10); + uint32_t log2minFreq = (mType == kLowShelf ? (32-10) : (32-2)); + if (LIKELY(normFreq > (1U << log2minFreq))) { + mFrequency = (Effects_log2(normFreq) - (log2minFreq << 15)) << (FREQ_PRECISION_BITS - 15); + } else { + mFrequency = 0; + } +} + +void AudioShelvingFilter::setGain(int32_t millibel) { + mGain = millibel + 9600; +} + +void AudioShelvingFilter::commit(bool immediate) { + audio_coef_t coefs[5]; + int intCoord[2] = { + mFrequency >> FREQ_PRECISION_BITS, + mGain >> GAIN_PRECISION_BITS + }; + uint32_t fracCoord[2] = { + mFrequency << (32 - FREQ_PRECISION_BITS), + static_cast<uint32_t>(mGain) << (32 - GAIN_PRECISION_BITS) + }; + if (mType == kHighShelf) { + mHiCoefInterp.getCoef(intCoord, fracCoord, coefs); + } else { + mLoCoefInterp.getCoef(intCoord, fracCoord, coefs); + } + mBiquad.setCoefs(coefs, immediate); +} + +} |