Add 1-pole high pass filter.

miniaudio.h

@@ -1733,10 +1733,24 @@ typedef struct
     ma_uint32 channels;
     ma_uint32 sampleRate;
     double cutoffFrequency;
-} ma_hpf2_config;
+} ma_hpf1_config, ma_hpf2_config;
 
+ma_hpf1_config ma_hpf1_config_init(ma_format format, ma_uint32 channels, ma_uint32 sampleRate, double cutoffFrequency);
 ma_hpf2_config ma_hpf2_config_init(ma_format format, ma_uint32 channels, ma_uint32 sampleRate, double cutoffFrequency);
 
+typedef struct
+{
+    ma_format format;
+    ma_uint32 channels;
+    ma_biquad_coefficient a;
+    ma_biquad_coefficient r1[MA_MAX_CHANNELS];
+} ma_hpf1;
+
+ma_result ma_hpf1_init(const ma_hpf1_config* pConfig, ma_hpf1* pHPF);
+ma_result ma_hpf1_reinit(const ma_hpf1_config* pConfig, ma_hpf1* pHPF);
+ma_result ma_hpf1_process_pcm_frames(ma_hpf1* pHPF, void* pFramesOut, const void* pFramesIn, ma_uint64 frameCount);
+ma_uint32 ma_hpf1_get_latency(ma_hpf1* pHPF);
+
 typedef struct
 {
     ma_biquad bq;   /* The 2-pole high-pass filter is implemented as a biquad filter. */
@@ -29828,6 +29842,19 @@ ma_uint32 ma_lpf_get_latency(ma_lpf* pLPF)
 High-Pass Filtering
 
 **************************************************************************************************************************************************************/
+ma_hpf1_config ma_hpf1_config_init(ma_format format, ma_uint32 channels, ma_uint32 sampleRate, double cutoffFrequency)
+{
+    ma_hpf1_config config;
+    
+    MA_ZERO_OBJECT(&config);
+    config.format = format;
+    config.channels = channels;
+    config.sampleRate = sampleRate;
+    config.cutoffFrequency = cutoffFrequency;
+
+    return config;
+}
+
 ma_hpf2_config ma_hpf2_config_init(ma_format format, ma_uint32 channels, ma_uint32 sampleRate, double cutoffFrequency)
 {
     ma_hpf2_config config;
@@ -29841,6 +29868,140 @@ ma_hpf2_config ma_hpf2_config_init(ma_format format, ma_uint32 channels, ma_uint
     return config;
 }
 
+
+ma_result ma_hpf1_init(const ma_hpf1_config* pConfig, ma_hpf1* pHPF)
+{
+    if (pHPF == NULL) {
+        return MA_INVALID_ARGS;
+    }
+
+    MA_ZERO_OBJECT(pHPF);
+
+    if (pConfig == NULL) {
+        return MA_INVALID_ARGS;
+    }
+
+    return ma_hpf1_reinit(pConfig, pHPF);
+}
+
+ma_result ma_hpf1_reinit(const ma_hpf1_config* pConfig, ma_hpf1* pHPF)
+{
+    double a;
+
+    if (pHPF == NULL || pConfig == NULL) {
+        return MA_INVALID_ARGS;
+    }
+
+    /* Only supporting f32 and s16. */
+    if (pConfig->format != ma_format_f32 && pConfig->format != ma_format_s16) {
+        return MA_INVALID_ARGS;
+    }
+
+    /* The format cannot be changed after initialization. */
+    if (pHPF->format != ma_format_unknown && pHPF->format != pConfig->format) {
+        return MA_INVALID_OPERATION;
+    }
+
+    /* The channel count cannot be changed after initialization. */
+    if (pHPF->channels != 0 && pHPF->channels != pConfig->channels) {
+        return MA_INVALID_OPERATION;
+    }
+
+    pHPF->format   = pConfig->format;
+    pHPF->channels = pConfig->channels;
+
+    a = ma_exp(-2 * MA_PI_D * pConfig->cutoffFrequency / pConfig->sampleRate);
+    if (pConfig->format == ma_format_f32) {
+        pHPF->a.f32 = (float)a;
+    } else {
+        pHPF->a.s32 = ma_biquad_float_to_fp(a);
+    }
+
+    return MA_SUCCESS;
+}
+
+static MA_INLINE void ma_hpf1_process_pcm_frame_f32(ma_hpf1* pHPF, float* pY, const float* pX)
+{
+    ma_uint32 c;
+    const float a = 1 - pHPF->a.f32;
+    const float b = 1 - a;
+    
+    for (c = 0; c < pHPF->channels; c += 1) {
+        float r1 = pHPF->r1[c].f32;
+        float x  = pX[c];
+        float y;
+
+        y = b*x - a*r1;
+
+        pY[c]           = y;
+        pHPF->r1[c].f32 = y;
+    }
+}
+
+static MA_INLINE void ma_hpf1_process_pcm_frame_s16(ma_hpf1* pHPF, ma_int16* pY, const ma_int16* pX)
+{
+    ma_uint32 c;
+    const ma_int32 a = ((1 << MA_BIQUAD_FIXED_POINT_SHIFT) - pHPF->a.s32);
+    const ma_int32 b = ((1 << MA_BIQUAD_FIXED_POINT_SHIFT) - a);
+    
+    for (c = 0; c < pHPF->channels; c += 1) {
+        ma_int32 r1 = pHPF->r1[c].s32;
+        ma_int32 x  = pX[c];
+        ma_int32 y;
+
+        y = (b*x - a*r1) >> MA_BIQUAD_FIXED_POINT_SHIFT;
+
+        pY[c]           = (ma_int16)y;
+        pHPF->r1[c].s32 = (ma_int32)y;
+    }
+}
+
+ma_result ma_hpf1_process_pcm_frames(ma_hpf1* pHPF, void* pFramesOut, const void* pFramesIn, ma_uint64 frameCount)
+{
+    ma_uint32 n;
+
+    if (pHPF == NULL || pFramesOut == NULL || pFramesIn == NULL) {
+        return MA_INVALID_ARGS;
+    }
+
+    /* Note that the logic below needs to support in-place filtering. That is, it must support the case where pFramesOut and pFramesIn are the same. */
+
+    if (pHPF->format == ma_format_f32) {
+        /* */ float* pY = (      float*)pFramesOut;
+        const float* pX = (const float*)pFramesIn;
+
+        for (n = 0; n < frameCount; n += 1) {
+            ma_hpf1_process_pcm_frame_f32(pHPF, pY, pX);
+            pY += pHPF->channels;
+            pX += pHPF->channels;
+        }
+    } else if (pHPF->format == ma_format_s16) {
+        /* */ ma_int16* pY = (      ma_int16*)pFramesOut;
+        const ma_int16* pX = (const ma_int16*)pFramesIn;
+
+        for (n = 0; n < frameCount; n += 1) {
+            ma_hpf1_process_pcm_frame_s16(pHPF, pY, pX);
+            pY += pHPF->channels;
+            pX += pHPF->channels;
+        }
+    } else {
+        MA_ASSERT(MA_FALSE);
+        return MA_INVALID_ARGS; /* Format not supported. Should never hit this because it's checked in ma_biquad_init() and ma_biquad_reinit(). */
+    }
+
+    return MA_SUCCESS;
+}
+
+ma_uint32 ma_hpf1_get_latency(ma_hpf1* pHPF)
+{
+    if (pHPF == NULL) {
+        return 0;
+    }
+
+    return 1;
+}
+
+
 static MA_INLINE ma_biquad_config ma_hpf2__get_biquad_config(const ma_hpf2_config* pConfig)
 {
     ma_biquad_config bqConfig;

tests/test_filtering/ma_test_filtering_hpf.c

 
-ma_result test_hpf__f32(const char* pInputFilePath)
+ma_result hpf_init_decoder_and_encoder(const char* pInputFilePath, const char* pOutputFilePath, ma_format format, ma_decoder* pDecoder, drwav* pEncoder)
+{
+    return filtering_init_decoder_and_encoder(pInputFilePath, pOutputFilePath, format, 0, 0, pDecoder, pEncoder);
+}
+
+ma_result test_hpf1__by_format(const char* pInputFilePath, const char* pOutputFilePath, ma_format format)
+{
+    ma_result result;
+    ma_decoder decoder;
+    drwav wav;
+    ma_hpf1_config hpfConfig;
+    ma_hpf1 hpf;
+
+    printf("    %s\n", pOutputFilePath);
+
+    result = hpf_init_decoder_and_encoder(pInputFilePath, pOutputFilePath, format, &decoder, &wav);
+    if (result != MA_SUCCESS) {
+        return result;
+    }
+
+    hpfConfig = ma_hpf1_config_init(decoder.outputFormat, decoder.outputChannels, decoder.outputSampleRate, 2000);
+    result = ma_hpf1_init(&hpfConfig, &hpf);
+    if (result != MA_SUCCESS) {
+        ma_decoder_uninit(&decoder);
+        drwav_uninit(&wav);
+        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_hpf1_process_pcm_frames(&hpf, tempOut, tempIn, framesJustRead);
+
+        /* Write to the WAV file. */
+        drwav_write_pcm_frames(&wav, framesJustRead, tempOut);
+
+        if (framesJustRead < framesToRead) {
+            break;
+        }
+    }
+
+    drwav_uninit(&wav);
+    return MA_SUCCESS;
+}
+
+ma_result test_hpf1__f32(const char* pInputFilePath)
+{
+    return test_hpf1__by_format(pInputFilePath, "output/hpf1_f32.wav", ma_format_f32);
+}
+
+ma_result test_hpf1__s16(const char* pInputFilePath)
+{
+    return test_hpf1__by_format(pInputFilePath, "output/hpf1_s16.wav", ma_format_f32);
+}
+
+
+ma_result test_hpf2__by_format(const char* pInputFilePath, const char* pOutputFilePath, ma_format format)
 {
-    const char* pOutputFilePath = "output/hpf_f32.wav";
     ma_result result;
-    ma_decoder_config decoderConfig;
     ma_decoder decoder;
-    drwav_data_format wavFormat;
     drwav wav;
     ma_hpf2_config hpfConfig;
     ma_hpf2 hpf;
-    
-    decoderConfig = ma_decoder_config_init(ma_format_f32, 0, 0);
-    result = ma_decoder_init_file(pInputFilePath, &decoderConfig, &decoder);
+
+    printf("    %s\n", pOutputFilePath);
+
+    result = hpf_init_decoder_and_encoder(pInputFilePath, pOutputFilePath, format, &decoder, &wav);
     if (result != MA_SUCCESS) {
         return result;
     }
@@ -20,15 +83,10 @@ ma_result test_hpf__f32(const char* pInputFilePath)
     result = ma_hpf2_init(&hpfConfig, &hpf);
     if (result != MA_SUCCESS) {
         ma_decoder_uninit(&decoder);
+        drwav_uninit(&wav);
         return result;
     }
 
-    wavFormat = drwav_data_format_from_minaudio_format(decoder.outputFormat, decoder.outputChannels, decoder.outputSampleRate);
-    if (!drwav_init_file_write(&wav, pOutputFilePath, &wavFormat, NULL)) {
-        ma_decoder_uninit(&decoder);
-        return MA_ERROR;
-    }
-
     for (;;) {
         ma_uint8 tempIn[4096];
         ma_uint8 tempOut[4096];
@@ -55,6 +113,16 @@ ma_result test_hpf__f32(const char* pInputFilePath)
     return MA_SUCCESS;
 }
 
+ma_result test_hpf2__f32(const char* pInputFilePath)
+{
+    return test_hpf2__by_format(pInputFilePath, "output/hpf2_f32.wav", ma_format_f32);
+}
+
+ma_result test_hpf2__s16(const char* pInputFilePath)
+{
+    return test_hpf2__by_format(pInputFilePath, "output/hpf2_s16.wav", ma_format_f32);
+}
+
 int test_entry__hpf(int argc, char** argv)
 {
     ma_result result;
@@ -68,7 +136,24 @@ int test_entry__hpf(int argc, char** argv)
 
     pInputFilePath = argv[1];
     
-    result = test_hpf__f32(pInputFilePath);
+
+    result = test_hpf1__f32(pInputFilePath);
+    if (result != MA_SUCCESS) {
+        hasError = MA_TRUE;
+    }
+
+    result = test_hpf1__s16(pInputFilePath);
+    if (result != MA_SUCCESS) {
+        hasError = MA_TRUE;
+    }
+
+
+    result = test_hpf2__f32(pInputFilePath);
+    if (result != MA_SUCCESS) {
+        hasError = MA_TRUE;
+    }
+
+    result = test_hpf2__s16(pInputFilePath);
     if (result != MA_SUCCESS) {
         hasError = MA_TRUE;
     }