Audio refactoring, filters and I2SConfig (#19662)

arendst · Oct 3, 2023 · 473a8ee · 473a8ee
1 parent e32c39f
commit 473a8ee
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Showing 6 changed files with 364 additions and 125 deletions.
diff --git a/lib/libesp32/berry_tasmota/src/be_i2s_audio_lib.c b/lib/libesp32/berry_tasmota/src/be_i2s_audio_lib.c
@@ -127,6 +127,18 @@ BE_FUNC_CTYPE_DECLARE(be_audio_input_i2s_get_channels, "i", ".");
 extern float be_audio_input_i2s_get_gain(void* in);
 BE_FUNC_CTYPE_DECLARE(be_audio_input_i2s_get_gain, "f", ".");
 
+// AudioInputI2S.get_dc_offset() -> float
+extern int be_audio_input_i2s_get_dc_offset(void* in);
+BE_FUNC_CTYPE_DECLARE(be_audio_input_i2s_get_dc_offset, "i", ".");
+
+// AudioInputI2S.get_lowpass_alpha() -> float
+extern float be_audio_input_i2s_get_lowpass_alpha(void* in);
+BE_FUNC_CTYPE_DECLARE(be_audio_input_i2s_get_lowpass_alpha, "f", ".");
+
+// AudioInputI2S.set_lowpass_alpha(alpha:float) -> bool
+extern int be_audio_input_i2s_set_lowpass_alpha(void* in, float alpha);
+BE_FUNC_CTYPE_DECLARE(be_audio_input_i2s_set_lowpass_alpha, "b", ".f");
+
 #include "be_fixed_be_class_AudioOutputI2S.h"
 #include "be_fixed_be_class_AudioGenerator.h"
 #include "be_fixed_be_class_AudioGeneratorWAV.h"
@@ -202,6 +214,10 @@ class be_class_AudioInputI2S (scope: global, name: AudioInputI2S, strings: weak)
     get_gain, ctype_func(be_audio_input_i2s_get_gain)
 
     set_gain, ctype_func(be_audio_input_set_gain)
+    get_dc_offset, ctype_func(be_audio_input_i2s_get_dc_offset)
+
+    get_lowpass_alpha, ctype_func(be_audio_input_i2s_get_lowpass_alpha)
+    set_lowpass_alpha, ctype_func(be_audio_input_i2s_set_lowpass_alpha)
 }
 
 @const_object_info_end */

diff --git a/tasmota/include/i18n.h b/tasmota/include/i18n.h
@@ -763,6 +763,11 @@
 #define D_CMND_PING "Ping"
 #define D_JSON_PING "Ping"
 
+// Commands xdrv_42_audio - I2S Audio
+#define D_PRFX_I2S "I2S"
+#define D_JSON_I2S_CONFIG "Config"
+
+
 // Commands xdrv_52_berry.ino - Berry scripting language
 #define D_PRFX_BR "Br"
 #define D_CMND_BR_RUN ""

diff --git a/tasmota/tasmota_xdrv_driver/xdrv_42_0_i2s_0_config_idf51.ino b/tasmota/tasmota_xdrv_driver/xdrv_42_0_i2s_0_config_idf51.ino
@@ -67,10 +67,11 @@ enum : int8_t {
 };
 
 #define I2S_SLOTS   2
+#define AUDIO_SETTINGS_VERSION  1
 
 typedef struct{
   struct{
-    uint8_t   version = 0;    // B00
+    uint8_t   version = AUDIO_SETTINGS_VERSION;    // B00
 
     // runtime options, will be saved but ignored on setting read
     bool      duplex = 0;           // B01 - depends on GPIO setting and SOC caps, DIN and DOUT on same port in GPIO means -> try to use duplex if possible
@@ -81,7 +82,8 @@ typedef struct{
     bool      mclk_inv[I2S_SLOTS] = {0};  // B05-06 - invert mclk
     bool      bclk_inv[I2S_SLOTS] = {0};  // B07-08 - invert bclk
     bool      ws_inv[I2S_SLOTS] = {0};    // B09-0A - invert ws
-    uint8_t   spare[5];              // B0B-0F
+    uint8_t   mp3_preallocate = 0;    // B0B - will be ignored without PS-RAM
+    uint8_t   spare[4];              // B0C-0F
   } sys;
   struct {
     uint32_t sample_rate = 16000;   // B00-03
@@ -91,26 +93,31 @@ typedef struct{
     uint8_t  slot_config = I2S_SLOT_MSB;// B07 - slot configuration MSB = 0, PCM = 1, PHILIPS = 2
     uint8_t  channels = 2;          // B08 - mono/stereo - 1 is added for both
     bool     apll = 1;              // B09 - will be ignored on unsupported SOC's
-    // device specific
-    uint8_t  mp3_preallocate = 0;   // B0A - preallocate MP3 buffer for mp3 playing
-    uint8_t  codec = 0;             // B0B - S3 box only, unused for now
-    uint8_t  spare[4];              // B0C-0F
+    uint8_t  spare[6];              // B0A-0F
   } tx;
   struct {
     uint32_t sample_rate = 16000;  // B00-03
-    uint8_t  gain = 30;            // B04
-    uint8_t  mode = I2S_MODE_PDM;  // B05 - I2S mode standard, PDM, TDM, DAC
-    uint8_t  slot_mask = I2S_SLOT_NOCHANGE;// B06 - slot mask 
-    uint8_t  slot_config = I2S_SLOT_MSB;// B07 - slot configuration MSB = 0, PCM = 1, PHILIPS = 2
-    uint8_t  channels = 1;         // B08 - mono/stereo - 1 is added for both
-    bool     apll = 1;              // B09 - will be ignored on unsupported SOC's
-    // device specific
-    uint8_t  codec = 0;             // B0A - S3 box only, unused for now
-    uint8_t  mp3_preallocate = 0;   // B0B - will be ignored without PS-RAM
-    uint8_t  spare[4];              // B0C-0F
+    uint16_t gain = 30 * 16;       // B04-05 - in Q12.4
+    uint8_t  mode = I2S_MODE_PDM;  // B06 - I2S mode standard, PDM, TDM, DAC
+    uint8_t  slot_mask = I2S_SLOT_NOCHANGE;// B07 - slot mask 
+    uint8_t  slot_config = I2S_SLOT_MSB;// B08 - slot configuration MSB = 0, PCM = 1, PHILIPS = 2
+    uint8_t  channels = 1;         // B09 - mono/stereo - 1 is added for both
+    // filters
+    uint16_t dc_filter_alpha = 0b0111111011111111;  // B0A-B0B - DC_block filter = (1-2^(-7)) Q32:1.31, or `0` if disabled
+    // low pass filter
+    // See: https://en.wikipedia.org/wiki/Low-pass_filter#Simple_infinite_impulse_response_filter
+    // For 3000Hz low pass filter, RC = 0.0000530786
+    // dt = 1/16000 = 0.0000625
+    // alpha = dt / (RC + dt) = 0.540757545
+    // alpha = (b) 0.100010100110111 = 0x4537
+    uint16_t lowpass_alpha = 0b0100010100110111;    // B0C-B0D - lowpass filter = 3000Hz for 16000Hz sample rate
+    bool     apll = 1;              // B0E - will be ignored on unsupported SOC's
+    uint8_t  spare[1];              // B0F
   } rx;
 } tI2SSettings;
 
+static_assert(sizeof(tI2SSettings) == 48, "tI2SSettings Size is not correct");
+
 typedef union {
   uint8_t data;
   struct {