diff options
Diffstat (limited to 'circuitpython/shared-module/audiomixer/Mixer.c')
| -rw-r--r-- | circuitpython/shared-module/audiomixer/Mixer.c | 365 |
1 files changed, 365 insertions, 0 deletions
diff --git a/circuitpython/shared-module/audiomixer/Mixer.c b/circuitpython/shared-module/audiomixer/Mixer.c new file mode 100644 index 0000000..d6569c6 --- /dev/null +++ b/circuitpython/shared-module/audiomixer/Mixer.c @@ -0,0 +1,365 @@ +/* + * This file is part of the Micro Python project, http://micropython.org/ + * + * The MIT License (MIT) + * + * Copyright (c) 2018 Scott Shawcroft for Adafruit Industries + * 2018 DeanM for Adafruit Industries + * 2019 Michael Schroeder + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include "shared-bindings/audiomixer/Mixer.h" +#include "shared-bindings/audiomixer/MixerVoice.h" + +#include <stdint.h> + +#include "py/runtime.h" +#include "shared-module/audiocore/__init__.h" +#include "shared-module/audiocore/RawSample.h" + +void common_hal_audiomixer_mixer_construct(audiomixer_mixer_obj_t *self, + uint8_t voice_count, + uint32_t buffer_size, + uint8_t bits_per_sample, + bool samples_signed, + uint8_t channel_count, + uint32_t sample_rate) { + self->len = buffer_size / 2 / sizeof(uint32_t) * sizeof(uint32_t); + + self->first_buffer = m_malloc(self->len, false); + if (self->first_buffer == NULL) { + common_hal_audiomixer_mixer_deinit(self); + mp_raise_msg(&mp_type_MemoryError, translate("Couldn't allocate first buffer")); + } + + self->second_buffer = m_malloc(self->len, false); + if (self->second_buffer == NULL) { + common_hal_audiomixer_mixer_deinit(self); + mp_raise_msg(&mp_type_MemoryError, translate("Couldn't allocate second buffer")); + } + + self->bits_per_sample = bits_per_sample; + self->samples_signed = samples_signed; + self->channel_count = channel_count; + self->sample_rate = sample_rate; + self->voice_count = voice_count; +} + +void common_hal_audiomixer_mixer_deinit(audiomixer_mixer_obj_t *self) { + self->first_buffer = NULL; + self->second_buffer = NULL; +} + +bool common_hal_audiomixer_mixer_deinited(audiomixer_mixer_obj_t *self) { + return self->first_buffer == NULL; +} + +uint32_t common_hal_audiomixer_mixer_get_sample_rate(audiomixer_mixer_obj_t *self) { + return self->sample_rate; +} + +uint8_t common_hal_audiomixer_mixer_get_channel_count(audiomixer_mixer_obj_t *self) { + return self->channel_count; +} + +uint8_t common_hal_audiomixer_mixer_get_bits_per_sample(audiomixer_mixer_obj_t *self) { + return self->bits_per_sample; +} + +bool common_hal_audiomixer_mixer_get_playing(audiomixer_mixer_obj_t *self) { + for (uint8_t v = 0; v < self->voice_count; v++) { + if (common_hal_audiomixer_mixervoice_get_playing(MP_OBJ_TO_PTR(self->voice[v]))) { + return true; + } + } + return false; +} + +void audiomixer_mixer_reset_buffer(audiomixer_mixer_obj_t *self, + bool single_channel_output, + uint8_t channel) { + for (uint8_t i = 0; i < self->voice_count; i++) { + common_hal_audiomixer_mixervoice_stop(self->voice[i]); + } +} + +__attribute__((always_inline)) +static inline uint32_t add16signed(uint32_t a, uint32_t b) { + #if (defined(__ARM_ARCH_7EM__) && (__ARM_ARCH_7EM__ == 1)) + return __QADD16(a, b); + #else + uint32_t result = 0; + for (int8_t i = 0; i < 2; i++) { + int16_t ai = a >> (sizeof(int16_t) * 8 * i); + int16_t bi = b >> (sizeof(int16_t) * 8 * i); + int32_t intermediate = (int32_t)ai + bi; + if (intermediate > SHRT_MAX) { + intermediate = SHRT_MAX; + } else if (intermediate < SHRT_MIN) { + intermediate = SHRT_MIN; + } + result |= (((uint32_t)intermediate) & 0xffff) << (sizeof(int16_t) * 8 * i); + } + return result; + #endif +} + +__attribute__((always_inline)) +static inline uint32_t mult16signed(uint32_t val, int32_t mul) { + #if (defined(__ARM_ARCH_7EM__) && (__ARM_ARCH_7EM__ == 1)) + mul <<= 16; + int32_t hi, lo; + enum { bits = 16 }; // saturate to 16 bits + enum { shift = 15 }; // shift is done automatically + asm volatile ("smulwb %0, %1, %2" : "=r" (lo) : "r" (mul), "r" (val)); + asm volatile ("smulwt %0, %1, %2" : "=r" (hi) : "r" (mul), "r" (val)); + asm volatile ("ssat %0, %1, %2, asr %3" : "=r" (lo) : "I" (bits), "r" (lo), "I" (shift)); + asm volatile ("ssat %0, %1, %2, asr %3" : "=r" (hi) : "I" (bits), "r" (hi), "I" (shift)); + asm volatile ("pkhbt %0, %1, %2, lsl #16" : "=r" (val) : "r" (lo), "r" (hi)); // pack + return val; + #else + uint32_t result = 0; + float mod_mul = (float)mul / (float)((1 << 15) - 1); + for (int8_t i = 0; i < 2; i++) { + int16_t ai = (val >> (sizeof(uint16_t) * 8 * i)); + int32_t intermediate = ai * mod_mul; + if (intermediate > SHRT_MAX) { + intermediate = SHRT_MAX; + } else if (intermediate < SHRT_MIN) { + intermediate = SHRT_MIN; + } + intermediate &= 0x0000FFFF; + result |= (((uint32_t)intermediate)) << (sizeof(int16_t) * 8 * i); + } + return result; + #endif +} + +static inline uint32_t tounsigned8(uint32_t val) { + #if (defined(__ARM_ARCH_7EM__) && (__ARM_ARCH_7EM__ == 1)) + return __UADD8(val, 0x80808080); + #else + return val ^ 0x80808080; + #endif +} + +static inline uint32_t tounsigned16(uint32_t val) { + #if (defined(__ARM_ARCH_7EM__) && (__ARM_ARCH_7EM__ == 1)) + return __UADD16(val, 0x80008000); + #else + return val ^ 0x80008000; + #endif +} + +static inline uint32_t tosigned16(uint32_t val) { + #if (defined(__ARM_ARCH_7EM__) && (__ARM_ARCH_7EM__ == 1)) + return __UADD16(val, 0x80008000); + #else + return val ^ 0x80008000; + #endif +} + +static inline uint32_t unpack8(uint16_t val) { + return ((val & 0xff00) << 16) | ((val & 0x00ff) << 8); +} + +static inline uint32_t pack8(uint32_t val) { + return ((val & 0xff000000) >> 16) | ((val & 0xff00) >> 8); +} + +static void mix_down_one_voice(audiomixer_mixer_obj_t *self, + audiomixer_mixervoice_obj_t *voice, bool voices_active, + uint32_t *word_buffer, uint32_t length) { + while (length != 0) { + if (voice->buffer_length == 0) { + if (!voice->more_data) { + if (voice->loop) { + audiosample_reset_buffer(voice->sample, false, 0); + } else { + voice->sample = NULL; + break; + } + } + if (voice->sample) { + // Load another buffer + audioio_get_buffer_result_t result = audiosample_get_buffer(voice->sample, false, 0, (uint8_t **)&voice->remaining_buffer, &voice->buffer_length); + // Track length in terms of words. + voice->buffer_length /= sizeof(uint32_t); + voice->more_data = result == GET_BUFFER_MORE_DATA; + } + } + + uint32_t n = MIN(voice->buffer_length, length); + uint32_t *src = voice->remaining_buffer; + uint16_t level = voice->level; + + // First active voice gets copied over verbatim. + if (!voices_active) { + if (MP_LIKELY(self->bits_per_sample == 16)) { + if (MP_LIKELY(self->samples_signed)) { + for (uint32_t i = 0; i < n; i++) { + uint32_t v = src[i]; + word_buffer[i] = mult16signed(v, level); + } + } else { + for (uint32_t i = 0; i < n; i++) { + uint32_t v = src[i]; + v = tosigned16(v); + word_buffer[i] = mult16signed(v, level); + } + } + } else { + uint16_t *hword_buffer = (uint16_t *)word_buffer; + uint16_t *hsrc = (uint16_t *)src; + for (uint32_t i = 0; i < n * 2; i++) { + uint32_t word = unpack8(hsrc[i]); + if (MP_LIKELY(!self->samples_signed)) { + word = tosigned16(word); + } + word = mult16signed(word, level); + hword_buffer[i] = pack8(word); + } + } + } else { + if (MP_LIKELY(self->bits_per_sample == 16)) { + if (MP_LIKELY(self->samples_signed)) { + for (uint32_t i = 0; i < n; i++) { + uint32_t word = src[i]; + word_buffer[i] = add16signed(mult16signed(word, level), word_buffer[i]); + } + } else { + for (uint32_t i = 0; i < n; i++) { + uint32_t word = src[i]; + word = tosigned16(word); + word_buffer[i] = add16signed(mult16signed(word, level), word_buffer[i]); + } + } + } else { + uint16_t *hword_buffer = (uint16_t *)word_buffer; + uint16_t *hsrc = (uint16_t *)src; + for (uint32_t i = 0; i < n * 2; i++) { + uint32_t word = unpack8(hsrc[i]); + if (MP_LIKELY(!self->samples_signed)) { + word = tosigned16(word); + } + word = mult16signed(word, level); + word = add16signed(word, unpack8(hword_buffer[i])); + hword_buffer[i] = pack8(word); + } + } + } + length -= n; + word_buffer += n; + voice->remaining_buffer += n; + voice->buffer_length -= n; + } + + if (length && !voices_active) { + for (uint32_t i = 0; i < length; i++) { + word_buffer[i] = 0; + } + } +} + +audioio_get_buffer_result_t audiomixer_mixer_get_buffer(audiomixer_mixer_obj_t *self, + bool single_channel_output, + uint8_t channel, + uint8_t **buffer, + uint32_t *buffer_length) { + if (!single_channel_output) { + channel = 0; + } + + uint32_t channel_read_count = self->left_read_count; + if (channel == 1) { + channel_read_count = self->right_read_count; + } + *buffer_length = self->len; + + bool need_more_data = self->read_count == channel_read_count; + if (need_more_data) { + uint32_t *word_buffer; + if (self->use_first_buffer) { + *buffer = (uint8_t *)self->first_buffer; + word_buffer = self->first_buffer; + } else { + *buffer = (uint8_t *)self->second_buffer; + word_buffer = self->second_buffer; + } + self->use_first_buffer = !self->use_first_buffer; + bool voices_active = false; + uint32_t length = self->len / sizeof(uint32_t); + + for (int32_t v = 0; v < self->voice_count; v++) { + audiomixer_mixervoice_obj_t *voice = MP_OBJ_TO_PTR(self->voice[v]); + if (voice->sample) { + mix_down_one_voice(self, voice, voices_active, word_buffer, length); + voices_active = true; + } + } + + if (!voices_active) { + for (uint32_t i = 0; i < length; i++) { + word_buffer[i] = 0; + } + } + + if (!self->samples_signed) { + if (self->bits_per_sample == 16) { + for (uint32_t i = 0; i < length; i++) { + word_buffer[i] = tounsigned16(word_buffer[i]); + } + } else { + for (uint32_t i = 0; i < length; i++) { + word_buffer[i] = tounsigned8(word_buffer[i]); + } + } + } + + self->read_count += 1; + } else if (!self->use_first_buffer) { + *buffer = (uint8_t *)self->first_buffer; + } else { + *buffer = (uint8_t *)self->second_buffer; + } + + + if (channel == 0) { + self->left_read_count += 1; + } else if (channel == 1) { + self->right_read_count += 1; + *buffer = *buffer + self->bits_per_sample / 8; + } + return GET_BUFFER_MORE_DATA; +} + +void audiomixer_mixer_get_buffer_structure(audiomixer_mixer_obj_t *self, bool single_channel_output, + bool *single_buffer, bool *samples_signed, + uint32_t *max_buffer_length, uint8_t *spacing) { + *single_buffer = false; + *samples_signed = self->samples_signed; + *max_buffer_length = self->len; + if (single_channel_output) { + *spacing = self->channel_count; + } else { + *spacing = 1; + } +} |