Add support for list of Biquad objects within audiofilters.Filter.

relic-se · relic-se · commit 6badb92de8b8 · 2024-10-29T12:52:27.000-05:00
diff --git a/shared-bindings/audiofilters/Filter.c b/shared-bindings/audiofilters/Filter.c
@@ -23,7 +23,7 @@
 //|
 //|     def __init__(
 //|         self,
-//|         filter: Optional[synthio.Biquad] = None,
+//|         filters: Optional[List[synthio.Biquad]] = None,
 //|         mix: synthio.BlockInput = 1.0,
 //|         buffer_size: int = 512,
 //|         sample_rate: int = 8000,
@@ -38,7 +38,7 @@
 //|            The mix parameter allows you to change how much of the unchanged sample passes through to
 //|            the output to how much of the effect audio you hear as the output.
 //|
-//|         :param Optional[synthio.Biquad] filter: The normalized biquad filter object used to process the signal.
+//|         :param Optional[List[synthio.Biquad]] filters: A list of normalized biquad filter objects used to process the signal.
 //|         :param synthio.BlockInput mix: The mix as a ratio of the sample (0.0) to the effect (1.0).
 //|         :param int buffer_size: The total size in bytes of each of the two playback buffers to use
 //|         :param int sample_rate: The sample rate to be used
@@ -56,9 +56,10 @@
 //|
 //|           audio = audiobusio.I2SOut(bit_clock=board.GP20, word_select=board.GP21, data=board.GP22)
 //|           synth = synthio.Synthesizer(channel_count=1, sample_rate=44100)
-//|           filter = audiofilters.Filter(filter=synth.low_pass_filter(frequency=2000, Q=1.25), buffer_size=1024, channel_count=1, sample_rate=44100, mix=1.0)
-//|           filter.play(synth)
-//|           audio.play(filter)
+//|           effect = audiofilters.Filter(buffer_size=1024, channel_count=1, sample_rate=44100, mix=1.0)
+//|           effect.filters.append(synth.low_pass_filter(frequency=2000, Q=1.25))
+//|           effect.play(synth)
+//|           audio.play(effect)
 //|
 //|           note = synthio.Note(261)
 //|           while True:
@@ -68,9 +69,9 @@
 //|               time.sleep(5)"""
 //|         ...
 static mp_obj_t audiofilters_filter_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
-    enum { ARG_filter, ARG_mix, ARG_buffer_size, ARG_sample_rate, ARG_bits_per_sample, ARG_samples_signed, ARG_channel_count, };
+    enum { ARG_filters, ARG_mix, ARG_buffer_size, ARG_sample_rate, ARG_bits_per_sample, ARG_samples_signed, ARG_channel_count, };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_filter, MP_ARG_OBJ | MP_ARG_KW_ONLY,  {.u_obj = MP_OBJ_NULL} },
+        { MP_QSTR_filters, MP_ARG_OBJ | MP_ARG_KW_ONLY, {.u_obj = MP_OBJ_NULL} },
         { MP_QSTR_mix, MP_ARG_OBJ | MP_ARG_KW_ONLY,  {.u_obj = MP_OBJ_NULL} },
         { MP_QSTR_buffer_size, MP_ARG_INT | MP_ARG_KW_ONLY, {.u_int = 512} },
         { MP_QSTR_sample_rate, MP_ARG_INT | MP_ARG_KW_ONLY, {.u_int = 8000} },
@@ -90,7 +91,7 @@ static mp_obj_t audiofilters_filter_make_new(const mp_obj_type_t *type, size_t n
     }
 
     audiofilters_filter_obj_t *self = mp_obj_malloc(audiofilters_filter_obj_t, &audiofilters_filter_type);
-    common_hal_audiofilters_filter_construct(self, args[ARG_filter].u_obj, args[ARG_mix].u_obj, args[ARG_buffer_size].u_int, bits_per_sample, args[ARG_samples_signed].u_bool, channel_count, sample_rate);
+    common_hal_audiofilters_filter_construct(self, args[ARG_filters].u_obj, args[ARG_mix].u_obj, args[ARG_buffer_size].u_int, bits_per_sample, args[ARG_samples_signed].u_bool, channel_count, sample_rate);
 
     return MP_OBJ_FROM_PTR(self);
 }
@@ -128,31 +129,34 @@ static mp_obj_t audiofilters_filter_obj___exit__(size_t n_args, const mp_obj_t *
 static MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(audiofilters_filter___exit___obj, 4, 4, audiofilters_filter_obj___exit__);
 
 
-//|     filter: Optional[synthio.Biquad]
-//|     """The normalized biquad filter object used to process the signal."""
-static mp_obj_t audiofilters_filter_obj_get_filter(mp_obj_t self_in) {
-    return common_hal_audiofilters_filter_get_filter(self_in);
+//|     filters: List[synthio.Biquad]
+//|     """A list of normalized biquad filter objects used to process the signal."""
+//|
+static mp_obj_t audiofilters_filter_obj_get_filters(mp_obj_t self_in) {
+    audiofilters_filter_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    check_for_deinit(self);
+    return common_hal_audiofilters_filter_get_filters(self);
 }
-MP_DEFINE_CONST_FUN_OBJ_1(audiofilters_filter_get_filter_obj, audiofilters_filter_obj_get_filter);
+MP_DEFINE_CONST_FUN_OBJ_1(audiofilters_filter_get_filters_obj, audiofilters_filter_obj_get_filters);
 
-static mp_obj_t audiofilters_filter_obj_set_filter(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
-    enum { ARG_filter };
+static mp_obj_t audiofilters_filter_obj_set_filters(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+    enum { ARG_filters };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_filter,     MP_ARG_OBJ | MP_ARG_REQUIRED, {} },
+        { MP_QSTR_filters,     MP_ARG_OBJ | MP_ARG_REQUIRED, {} },
     };
     audiofilters_filter_obj_t *self = MP_OBJ_TO_PTR(pos_args[0]);
     mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
     mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
 
-    common_hal_audiofilters_filter_set_filter(self, args[ARG_filter].u_obj);
+    common_hal_audiofilters_filter_set_filters(self, args[ARG_filters].u_obj);
 
     return mp_const_none;
 }
-MP_DEFINE_CONST_FUN_OBJ_KW(audiofilters_filter_set_filter_obj, 1, audiofilters_filter_obj_set_filter);
+MP_DEFINE_CONST_FUN_OBJ_KW(audiofilters_filter_set_filters_obj, 1, audiofilters_filter_obj_set_filters);
 
-MP_PROPERTY_GETSET(audiofilters_filter_filter_obj,
-    (mp_obj_t)&audiofilters_filter_get_filter_obj,
-    (mp_obj_t)&audiofilters_filter_set_filter_obj);
+MP_PROPERTY_GETSET(audiofilters_filter_filters_obj,
+    (mp_obj_t)&audiofilters_filter_get_filters_obj,
+    (mp_obj_t)&audiofilters_filter_set_filters_obj);
 
 
 //|     mix: synthio.BlockInput
@@ -241,7 +245,7 @@ static const mp_rom_map_elem_t audiofilters_filter_locals_dict_table[] = {
 
     // Properties
     { MP_ROM_QSTR(MP_QSTR_playing), MP_ROM_PTR(&audiofilters_filter_playing_obj) },
-    { MP_ROM_QSTR(MP_QSTR_filter), MP_ROM_PTR(&audiofilters_filter_filter_obj) },
+    { MP_ROM_QSTR(MP_QSTR_filters), MP_ROM_PTR(&audiofilters_filter_filters_obj) },
     { MP_ROM_QSTR(MP_QSTR_mix), MP_ROM_PTR(&audiofilters_filter_mix_obj) },
 };
 static MP_DEFINE_CONST_DICT(audiofilters_filter_locals_dict, audiofilters_filter_locals_dict_table);
diff --git a/shared-bindings/audiofilters/Filter.h b/shared-bindings/audiofilters/Filter.h
@@ -11,7 +11,7 @@
 extern const mp_obj_type_t audiofilters_filter_type;
 
 void common_hal_audiofilters_filter_construct(audiofilters_filter_obj_t *self,
-    mp_obj_t filter, mp_obj_t mix,
+    mp_obj_t filters, mp_obj_t mix,
     uint32_t buffer_size, uint8_t bits_per_sample, bool samples_signed,
     uint8_t channel_count, uint32_t sample_rate);
 
@@ -22,8 +22,8 @@ uint32_t common_hal_audiofilters_filter_get_sample_rate(audiofilters_filter_obj_
 uint8_t common_hal_audiofilters_filter_get_channel_count(audiofilters_filter_obj_t *self);
 uint8_t common_hal_audiofilters_filter_get_bits_per_sample(audiofilters_filter_obj_t *self);
 
-mp_obj_t common_hal_audiofilters_filter_get_filter(audiofilters_filter_obj_t *self);
-void common_hal_audiofilters_filter_set_filter(audiofilters_filter_obj_t *self, mp_obj_t arg);
+mp_obj_t common_hal_audiofilters_filter_get_filters(audiofilters_filter_obj_t *self);
+void common_hal_audiofilters_filter_set_filters(audiofilters_filter_obj_t *self, mp_obj_t arg);
 
 mp_obj_t common_hal_audiofilters_filter_get_mix(audiofilters_filter_obj_t *self);
 void common_hal_audiofilters_filter_set_mix(audiofilters_filter_obj_t *self, mp_obj_t arg);
diff --git a/shared-module/audiofilters/Filter.c b/shared-module/audiofilters/Filter.c
@@ -9,7 +9,7 @@
 #include "py/runtime.h"
 
 void common_hal_audiofilters_filter_construct(audiofilters_filter_obj_t *self,
-    mp_obj_t filter, mp_obj_t mix,
+    mp_obj_t filters, mp_obj_t mix,
     uint32_t buffer_size, uint8_t bits_per_sample,
     bool samples_signed, uint8_t channel_count, uint32_t sample_rate) {
 
@@ -60,12 +60,12 @@ void common_hal_audiofilters_filter_construct(audiofilters_filter_obj_t *self,
 
     // The below section sets up the effect's starting values.
 
-    if (filter == MP_OBJ_NULL) {
-        filter = mp_const_none;
+    if (filters == MP_OBJ_NULL) {
+        filters = mp_obj_new_list(0, NULL);
     }
-    synthio_biquad_filter_assign(&self->filter_state, filter);
-    self->filter_obj = filter;
-
+    self->filters = filters;
+    reset_filter_states(self);
+    
     // If we did not receive a BlockInput we need to create a default float value
     if (mix == MP_OBJ_NULL) {
         mix = mp_obj_new_float(1.0);
@@ -87,15 +87,37 @@ void common_hal_audiofilters_filter_deinit(audiofilters_filter_obj_t *self) {
     self->buffer[0] = NULL;
     self->buffer[1] = NULL;
     self->filter_buffer = NULL;
+    self->filter_states = NULL;
+}
+
+void reset_filter_states(audiofilters_filter_obj_t *self) {
+    self->filter_states_len = self->filters->len;
+    self->filter_states = NULL;
+
+    if (self->filter_states_len) {
+        self->filter_states = m_malloc(self->filter_states_len * sizeof(biquad_filter_state));
+        if (self->filter_states == NULL) {
+            common_hal_audiofilters_filter_deinit(self);
+            m_malloc_fail(self->filter_states_len * sizeof(biquad_filter_state));
+        }
+
+        mp_obj_iter_buf_t iter_buf;
+        mp_obj_t iterable = mp_getiter(self->filters, &iter_buf);
+        mp_obj_t item;
+        uint8_t i = 0;
+        while ((item = mp_iternext(iterable)) != MP_OBJ_STOP_ITERATION) {
+            synthio_biquad_filter_assign(&self->filter_states[i++], item);
+        }
+    }
 }
 
-mp_obj_t common_hal_audiofilters_filter_get_filter(audiofilters_filter_obj_t *self) {
-    return self->filter_obj;
+mp_obj_t common_hal_audiofilters_filter_get_filters(audiofilters_filter_obj_t *self) {
+    return self->filters;
 }
 
-void common_hal_audiofilters_filter_set_filter(audiofilters_filter_obj_t *self, mp_obj_t arg) {
-    synthio_biquad_filter_assign(&self->filter_state, arg);
-    self->filter_obj = arg;
+void common_hal_audiofilters_filter_set_filters(audiofilters_filter_obj_t *self, mp_obj_t arg) {
+    self->filters = arg;
+    reset_filter_states(self);
 }
 
 mp_obj_t common_hal_audiofilters_filter_get_mix(audiofilters_filter_obj_t *self) {
@@ -126,7 +148,9 @@ void audiofilters_filter_reset_buffer(audiofilters_filter_obj_t *self,
     memset(self->buffer[1], 0, self->buffer_len);
     memset(self->filter_buffer, 0, SYNTHIO_MAX_DUR * sizeof(int32_t));
 
-    synthio_biquad_filter_reset(&self->filter_state);
+    for (uint8_t i = 0; i < self->filter_states_len; i++) {
+        synthio_biquad_filter_reset(&self->filter_states[i]);
+    }
 }
 
 bool common_hal_audiofilters_filter_get_playing(audiofilters_filter_obj_t *self) {
@@ -209,6 +233,11 @@ audioio_get_buffer_result_t audiofilters_filter_get_buffer(audiofilters_filter_o
         channel = 0;
     }
 
+    // Update filter_states if filters list has been appended or removed
+    if (self->filters->len != self->filter_states_len) {
+        reset_filter_states(self);
+    }
+
     // get the effect values we need from the BlockInput. These may change at run time so you need to do bounds checking if required
     mp_float_t mix = MIN(1.0, MAX(synthio_block_slot_get(&self->mix), 0.0));
 
@@ -248,7 +277,7 @@ audioio_get_buffer_result_t audiofilters_filter_get_buffer(audiofilters_filter_o
             int16_t *sample_src = (int16_t *)self->sample_remaining_buffer; // for 16-bit samples
             int8_t *sample_hsrc = (int8_t *)self->sample_remaining_buffer; // for 8-bit samples
 
-            if (mix <= 0.01 || self->filter_obj == mp_const_none) { // if mix is zero pure sample only or no biquad filter object is provided
+            if (mix <= 0.01 || !self->filter_states_len) { // if mix is zero pure sample only or no biquad filter objects are provided
                 for (uint32_t i = 0; i < n; i++) {
                     if (MP_LIKELY(self->bits_per_sample == 16)) {
                         word_buffer[i] = sample_src[i];
@@ -275,8 +304,10 @@ audioio_get_buffer_result_t audiofilters_filter_get_buffer(audiofilters_filter_o
                         }
                     }
 
-                    // Process biquad filter
-                    synthio_biquad_filter_samples(&self->filter_state, self->filter_buffer, n_samples);
+                    // Process biquad filters
+                    for (uint8_t j = 0; j < self->filter_states_len; j++) {
+                        synthio_biquad_filter_samples(&self->filter_states[j], self->filter_buffer, n_samples);
+                    }
 
                     // Mix processed signal with original sample and transfer to output buffer
                     for (uint32_t j = 0; j < n_samples; j++) {
diff --git a/shared-module/audiofilters/Filter.h b/shared-module/audiofilters/Filter.h
@@ -15,10 +15,11 @@ extern const mp_obj_type_t audiofilters_filter_type;
 
 typedef struct {
     mp_obj_base_t base;
-    mp_obj_t filter_obj;
+    mp_obj_list_t *filters;
     synthio_block_slot_t mix;
 
-    biquad_filter_state filter_state;
+    uint8_t filter_states_len;
+    biquad_filter_state *filter_states;
 
     uint8_t bits_per_sample;
     bool samples_signed;
@@ -40,6 +41,8 @@ typedef struct {
     mp_obj_t sample;
 } audiofilters_filter_obj_t;
 
+void reset_filter_states(audiofilters_filter_obj_t *self);
+
 void audiofilters_filter_reset_buffer(audiofilters_filter_obj_t *self,
     bool single_channel_output,
     uint8_t channel);
