From 5b385670f3ed96f9a06b6abfa2ccfa4f5994a780 Mon Sep 17 00:00:00 2001 From: David Reid Date: Sun, 23 Feb 2020 21:03:22 +1000 Subject: [PATCH] Add second order low shelf filter. --- miniaudio.h | 174 +++++++++++++++++- tests/test_filtering/ma_test_filtering.c | 11 +- .../ma_test_filtering_loshelf.c | 168 +++++++++++++++++ 3 files changed, 346 insertions(+), 7 deletions(-) create mode 100644 tests/test_filtering/ma_test_filtering_loshelf.c diff --git a/miniaudio.h b/miniaudio.h index 667db2f6..89a02f56 100644 --- a/miniaudio.h +++ b/miniaudio.h @@ -1898,6 +1898,34 @@ ma_result ma_peak2_process_pcm_frames(ma_peak2* pFilter, void* pFramesOut, const ma_uint32 ma_peak2_get_latency(ma_peak2* pFilter); +/************************************************************************************************************************************************************** + +Low Shelf Filter + +**************************************************************************************************************************************************************/ +typedef struct +{ + ma_format format; + ma_uint32 channels; + ma_uint32 sampleRate; + double gainDB; + double shelfSlope; + double frequency; +} ma_loshelf2_config; + +ma_loshelf2_config ma_loshelf2_config_init(ma_format format, ma_uint32 channels, ma_uint32 sampleRate, double gainDB, double shelfSlope, double frequency); + +typedef struct +{ + ma_biquad bq; +} ma_loshelf2; + +ma_result ma_loshelf2_init(const ma_loshelf2_config* pConfig, ma_loshelf2* pFilter); +ma_result ma_loshelf2_reinit(const ma_loshelf2_config* pConfig, ma_loshelf2* pFilter); +ma_result ma_loshelf2_process_pcm_frames(ma_loshelf2* pFilter, void* pFramesOut, const void* pFramesIn, ma_uint64 frameCount); +ma_uint32 ma_loshelf2_get_latency(ma_loshelf2* pFilter); + + /************************************************************************************************************************************************************ ************************************************************************************************************************************************************* @@ -5725,11 +5753,6 @@ static MA_INLINE double ma_sin(double x) return sin(x); } -static MA_INLINE double ma_cos(double x) -{ - return ma_sin((MA_PI*0.5) - x); -} - static MA_INLINE double ma_exp(double x) { /* TODO: Implement custom exp(x). */ @@ -5748,6 +5771,18 @@ static MA_INLINE double ma_pow(double x, double y) return pow(x, y); } +static MA_INLINE double ma_sqrt(double x) +{ + /* TODO: Implement custom sqrt(x). */ + return sqrt(x); +} + + +static MA_INLINE double ma_cos(double x) +{ + return ma_sin((MA_PI*0.5) - x); +} + static MA_INLINE double ma_log10(double x) { return ma_log(x) * 0.43429448190325182765; @@ -31148,6 +31183,135 @@ ma_uint32 ma_peak2_get_latency(ma_peak2* pFilter) } +/************************************************************************************************************************************************************** + +Low Shelf Filter + +**************************************************************************************************************************************************************/ +ma_loshelf2_config ma_loshelf2_config_init(ma_format format, ma_uint32 channels, ma_uint32 sampleRate, double gainDB, double shelfSlope, double frequency) +{ + ma_loshelf2_config config; + + MA_ZERO_OBJECT(&config); + config.format = format; + config.channels = channels; + config.sampleRate = sampleRate; + config.gainDB = gainDB; + config.shelfSlope = shelfSlope; + config.frequency = frequency; + + if (config.gainDB == 0) { + config.gainDB = 6; + } + + return config; +} + + +static MA_INLINE ma_biquad_config ma_loshelf2__get_biquad_config(const ma_loshelf2_config* pConfig) +{ + ma_biquad_config bqConfig; + double w; + double s; + double c; + double A; + double S; + double a; + double sqrtA; + + MA_ASSERT(pConfig != NULL); + + w = 2 * MA_PI_D * pConfig->frequency / pConfig->sampleRate; + s = ma_sin(w); + c = ma_cos(w); + A = ma_pow(10, (pConfig->gainDB / 40)); + S = pConfig->shelfSlope; + a = s/2 * ma_sqrt((A + 1/A) * (1/S - 1) + 2); + sqrtA = 2*ma_sqrt(A)*a; + + bqConfig.b0 = A * ((A + 1) - (A - 1)*c + sqrtA); + bqConfig.b1 = 2 * A * ((A - 1) - (A + 1)*c); + bqConfig.b2 = A * ((A + 1) - (A - 1)*c - sqrtA); + bqConfig.a0 = (A + 1) + (A - 1)*c + sqrtA; + bqConfig.a1 = -2 * ((A - 1) + (A + 1)*c); + bqConfig.a2 = (A + 1) + (A - 1)*c - sqrtA; + + bqConfig.format = pConfig->format; + bqConfig.channels = pConfig->channels; + + return bqConfig; +} + +ma_result ma_loshelf2_init(const ma_loshelf2_config* pConfig, ma_loshelf2* pFilter) +{ + ma_result result; + ma_biquad_config bqConfig; + + if (pFilter == NULL) { + return MA_INVALID_ARGS; + } + + MA_ZERO_OBJECT(pFilter); + + if (pConfig == NULL) { + return MA_INVALID_ARGS; + } + + bqConfig = ma_loshelf2__get_biquad_config(pConfig); + result = ma_biquad_init(&bqConfig, &pFilter->bq); + if (result != MA_SUCCESS) { + return result; + } + + return MA_SUCCESS; +} + +ma_result ma_loshelf2_reinit(const ma_loshelf2_config* pConfig, ma_loshelf2* pFilter) +{ + ma_result result; + ma_biquad_config bqConfig; + + if (pFilter == NULL || pConfig == NULL) { + return MA_INVALID_ARGS; + } + + bqConfig = ma_loshelf2__get_biquad_config(pConfig); + result = ma_biquad_reinit(&bqConfig, &pFilter->bq); + if (result != MA_SUCCESS) { + return result; + } + + return MA_SUCCESS; +} + +static MA_INLINE void ma_loshelf2_process_pcm_frame_s16(ma_loshelf2* pFilter, ma_int16* pFrameOut, const ma_int16* pFrameIn) +{ + ma_biquad_process_pcm_frame_s16(&pFilter->bq, pFrameOut, pFrameIn); +} + +static MA_INLINE void ma_loshelf2_process_pcm_frame_f32(ma_loshelf2* pFilter, float* pFrameOut, const float* pFrameIn) +{ + ma_biquad_process_pcm_frame_f32(&pFilter->bq, pFrameOut, pFrameIn); +} + +ma_result ma_loshelf2_process_pcm_frames(ma_loshelf2* pFilter, void* pFramesOut, const void* pFramesIn, ma_uint64 frameCount) +{ + if (pFilter == NULL) { + return MA_INVALID_ARGS; + } + + return ma_biquad_process_pcm_frames(&pFilter->bq, pFramesOut, pFramesIn, frameCount); +} + +ma_uint32 ma_loshelf2_get_latency(ma_loshelf2* pFilter) +{ + if (pFilter == NULL) { + return 0; + } + + return ma_biquad_get_latency(&pFilter->bq); +} + /************************************************************************************************************************************************************** diff --git a/tests/test_filtering/ma_test_filtering.c b/tests/test_filtering/ma_test_filtering.c index d926bce3..a500d903 100644 --- a/tests/test_filtering/ma_test_filtering.c +++ b/tests/test_filtering/ma_test_filtering.c @@ -26,8 +26,9 @@ ma_result filtering_init_decoder_and_encoder(const char* pInputFilePath, const c #include "ma_test_filtering_lpf.c" #include "ma_test_filtering_hpf.c" #include "ma_test_filtering_bpf.c" -#include "ma_test_filtering_peak.c" #include "ma_test_filtering_notch.c" +#include "ma_test_filtering_peak.c" +#include "ma_test_filtering_loshelf.c" int main(int argc, char** argv) { @@ -59,16 +60,22 @@ int main(int argc, char** argv) hasError = MA_TRUE; } + result = ma_register_test("Notching Filtering", test_entry__notch); + if (result != MA_SUCCESS) { + hasError = MA_TRUE; + } + result = ma_register_test("Peaking EQ Filtering", test_entry__peak); if (result != MA_SUCCESS) { hasError = MA_TRUE; } #endif - result = ma_register_test("Notching Filtering", test_entry__notch); + result = ma_register_test("Low Shelf Filtering", test_entry__loshelf); if (result != MA_SUCCESS) { hasError = MA_TRUE; } + for (iTest = 0; iTest < g_Tests.count; iTest += 1) { printf("=== BEGIN %s ===\n", g_Tests.pTests[iTest].pName); diff --git a/tests/test_filtering/ma_test_filtering_loshelf.c b/tests/test_filtering/ma_test_filtering_loshelf.c new file mode 100644 index 00000000..b2d96ae2 --- /dev/null +++ b/tests/test_filtering/ma_test_filtering_loshelf.c @@ -0,0 +1,168 @@ +ma_result loshelf_init_decoder_and_encoder(const char* pInputFilePath, const char* pOutputFilePath, ma_format format, ma_decoder* pDecoder, ma_encoder* pEncoder) +{ + return filtering_init_decoder_and_encoder(pInputFilePath, pOutputFilePath, format, 0, 0, pDecoder, pEncoder); +} + + +ma_result test_loshelf2__by_format(const char* pInputFilePath, const char* pOutputFilePath, ma_format format) +{ + ma_result result; + ma_decoder decoder; + ma_encoder encoder; + ma_loshelf2_config loshelfConfig; + ma_loshelf2 loshelf; + + printf(" %s\n", pOutputFilePath); + + result = loshelf_init_decoder_and_encoder(pInputFilePath, pOutputFilePath, format, &decoder, &encoder); + if (result != MA_SUCCESS) { + return result; + } + + loshelfConfig = ma_loshelf2_config_init(decoder.outputFormat, decoder.outputChannels, decoder.outputSampleRate, 6, 1, 1000); + result = ma_loshelf2_init(&loshelfConfig, &loshelf); + if (result != MA_SUCCESS) { + ma_decoder_uninit(&decoder); + ma_encoder_uninit(&encoder); + return result; + } + + for (;;) { + ma_uint8 tempIn[4096]; + ma_uint8 tempOut[4096]; + ma_uint64 tempCapIn = sizeof(tempIn) / ma_get_bytes_per_frame(decoder.outputFormat, decoder.outputChannels); + ma_uint64 tempCapOut = sizeof(tempOut) / ma_get_bytes_per_frame(decoder.outputFormat, decoder.outputChannels); + ma_uint64 framesToRead; + ma_uint64 framesJustRead; + + framesToRead = ma_min(tempCapIn, tempCapOut); + framesJustRead = ma_decoder_read_pcm_frames(&decoder, tempIn, framesToRead); + + /* Filter */ + ma_loshelf2_process_pcm_frames(&loshelf, tempOut, tempIn, framesJustRead); + + /* Write to the WAV file. */ + ma_encoder_write_pcm_frames(&encoder, tempOut, framesJustRead); + + if (framesJustRead < framesToRead) { + break; + } + } + + ma_encoder_uninit(&encoder); + return MA_SUCCESS; +} + +ma_result test_loshelf2__f32(const char* pInputFilePath) +{ + return test_loshelf2__by_format(pInputFilePath, "output/loshelf2_f32.wav", ma_format_f32); +} + +ma_result test_loshelf2__s16(const char* pInputFilePath) +{ + return test_loshelf2__by_format(pInputFilePath, "output/loshelf2_s16.wav", ma_format_s16); +} + +#if 0 +ma_result test_loshelf4__by_format(const char* pInputFilePath, const char* pOutputFilePath, ma_format format) +{ + ma_result result; + ma_decoder decoder; + ma_encoder encoder; + ma_loshelf_config loshelfConfig; + ma_loshelf loshelf; + + printf(" %s\n", pOutputFilePath); + + result = loshelf_init_decoder_and_encoder(pInputFilePath, pOutputFilePath, format, &decoder, &encoder); + if (result != MA_SUCCESS) { + return result; + } + + loshelfConfig = ma_loshelf_config_init(decoder.outputFormat, decoder.outputChannels, decoder.outputSampleRate, 2000, 4); + result = ma_loshelf_init(&loshelfConfig, &loshelf); + if (result != MA_SUCCESS) { + ma_decoder_uninit(&decoder); + ma_encoder_uninit(&encoder); + return result; + } + + for (;;) { + ma_uint8 tempIn[4096]; + ma_uint8 tempOut[4096]; + ma_uint64 tempCapIn = sizeof(tempIn) / ma_get_bytes_per_frame(decoder.outputFormat, decoder.outputChannels); + ma_uint64 tempCapOut = sizeof(tempOut) / ma_get_bytes_per_frame(decoder.outputFormat, decoder.outputChannels); + ma_uint64 framesToRead; + ma_uint64 framesJustRead; + + framesToRead = ma_min(tempCapIn, tempCapOut); + framesJustRead = ma_decoder_read_pcm_frames(&decoder, tempIn, framesToRead); + + /* Filter */ + ma_loshelf_process_pcm_frames(&loshelf, tempOut, tempIn, framesJustRead); + + /* Write to the WAV file. */ + ma_encoder_write_pcm_frames(&encoder, tempOut, framesJustRead); + + if (framesJustRead < framesToRead) { + break; + } + } + + ma_encoder_uninit(&encoder); + return MA_SUCCESS; +} + +ma_result test_loshelf4__f32(const char* pInputFilePath) +{ + return test_loshelf4__by_format(pInputFilePath, "output/loshelf4_f32.wav", ma_format_f32); +} + +ma_result test_loshelf4__s16(const char* pInputFilePath) +{ + return test_loshelf4__by_format(pInputFilePath, "output/loshelf4_s16.wav", ma_format_s16); +} +#endif + +int test_entry__loshelf(int argc, char** argv) +{ + ma_result result; + ma_bool32 hasError = MA_FALSE; + const char* pInputFilePath; + + if (argc < 2) { + printf("No input file.\n"); + return -1; + } + + pInputFilePath = argv[1]; + + + result = test_loshelf2__f32(pInputFilePath); + if (result != MA_SUCCESS) { + hasError = MA_TRUE; + } + + result = test_loshelf2__s16(pInputFilePath); + if (result != MA_SUCCESS) { + hasError = MA_TRUE; + } + +#if 0 + result = test_loshelf4__f32(pInputFilePath); + if (result != MA_SUCCESS) { + hasError = MA_TRUE; + } + + result = test_loshelf4__s16(pInputFilePath); + if (result != MA_SUCCESS) { + hasError = MA_TRUE; + } +#endif + + if (hasError) { + return -1; + } else { + return 0; + } +}