Use block writes for BT audio consumers (earlephilhower#2204)

earlephilhower · web-flow · commit 0f05ad1cc2b6 · 2024-06-05T16:03:35.000-07:00
Around 2x the performance, and every bit is needed w/BT SBC compression
and decompression.
diff --git a/libraries/BluetoothAudio/src/BluetoothAudioConsumerI2S.cpp b/libraries/BluetoothAudio/src/BluetoothAudioConsumerI2S.cpp
@@ -75,10 +75,8 @@ void BluetoothAudioConsumerI2S::fill() {
         _a2dpSink->playback_handler((int16_t *) buff, 32);
         num_samples -= 64;
         for (int i = 0; i < 64; i++) {
-            int32_t tmp = buff[i];
-            tmp *= _gain;
-            tmp >>= 8;
-            _i2s->write((int16_t)tmp);
+            buff[i] = (((int32_t)buff[i]) * _gain) >> 8;
         }
+        _i2s->write((uint8_t *)buff, 64 * 2);
     }
 }
diff --git a/libraries/BluetoothAudio/src/BluetoothAudioConsumerPWM.cpp b/libraries/BluetoothAudio/src/BluetoothAudioConsumerPWM.cpp
@@ -76,10 +76,8 @@ void BluetoothAudioConsumerPWM::fill() {
         _a2dpSink->playback_handler((int16_t *) buff, 32);
         num_samples -= 64;
         for (int i = 0; i < 64; i++) {
-            int32_t tmp = buff[i];
-            tmp *= _gain;
-            tmp >>= 8;
-            _pwm->write((int16_t)tmp);
+            buff[i] = (((int32_t)buff[i]) * _gain) >> 8;
         }
+        _pwm->write((uint8_t *)buff, 64 * 2);
     }
 }

Original file line number	Diff line number	Diff line change
`@@ -75,10 +75,8 @@ void BluetoothAudioConsumerI2S::fill() {`
`75`	`75`	`_a2dpSink->playback_handler((int16_t *) buff, 32);`
`76`	`76`	`num_samples -= 64;`
`77`	`77`	`for (int i = 0; i < 64; i++) {`
`78`		`- int32_t tmp = buff[i];`
`79`		`- tmp *= _gain;`
`80`		`- tmp >>= 8;`
`81`		`- _i2s->write((int16_t)tmp);`
	`78`	`+ buff[i] = (((int32_t)buff[i]) * _gain) >> 8;`
`82`	`79`	`}`
	`80`	`+ _i2s->write((uint8_t )buff, 64 2);`
`83`	`81`	`}`
`84`	`82`	`}`
Original file line number	Diff line number	Diff line change
`@@ -76,10 +76,8 @@ void BluetoothAudioConsumerPWM::fill() {`
`76`	`76`	`_a2dpSink->playback_handler((int16_t *) buff, 32);`
`77`	`77`	`num_samples -= 64;`
`78`	`78`	`for (int i = 0; i < 64; i++) {`
`79`		`- int32_t tmp = buff[i];`
`80`		`- tmp *= _gain;`
`81`		`- tmp >>= 8;`
`82`		`- _pwm->write((int16_t)tmp);`
	`79`	`+ buff[i] = (((int32_t)buff[i]) * _gain) >> 8;`
`83`	`80`	`}`
	`81`	`+ _pwm->write((uint8_t )buff, 64 2);`
`84`	`82`	`}`
`85`	`83`	`}`