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// This file is part of the CircuitPython project: https://circuitpython.org
//
// SPDX-FileCopyrightText: Copyright (c) 2018 Scott Shawcroft for Adafruit Industries
// SPDX-FileCopyrightText: Copyright (c) 2019 Jeff Epler for Adafruit Industries
//
// SPDX-License-Identifier: MIT
#include <stdint.h>
#include "shared/runtime/context_manager_helpers.h"
#include "shared-bindings/audiocore/__init__.h"
#include "py/objproperty.h"
#include "py/runtime.h"
#include "py/stream.h"
#include "shared-bindings/audiomp3/MP3Decoder.h"
#include "shared-bindings/util.h"
//| class MP3Decoder:
//| """Load a mp3 file for audio playback
//|
//| .. note::
//|
//| ``MP3Decoder`` uses a lot of contiguous memory, so care should be given to
//| optimizing memory usage. More information and recommendations can be found here:
//| https://learn.adafruit.com/Memory-saving-tips-for-CircuitPython/reducing-memory-fragmentation
//| """
//|
//| def __init__(self, file: Union[str, typing.BinaryIO], buffer: WriteableBuffer) -> None:
//| """Load a .mp3 file for playback with `audioio.AudioOut` or `audiobusio.I2SOut`.
//|
//| :param Union[str, typing.BinaryIO] file: The name of a mp3 file (preferred) or an already opened mp3 file
//| :param ~circuitpython_typing.WriteableBuffer buffer: Optional pre-allocated buffer, that will be split and used for buffering the data. The buffer is split into two parts for decoded data and the remainder is used for pre-decoded data. When playing from a socket, a larger buffer can help reduce playback glitches at the expense of increased memory usage.
//|
//| Playback of mp3 audio is CPU intensive, and the
//| exact limit depends on many factors such as the particular
//| microcontroller, SD card or flash performance, network performance, and
//| other code in use such as displayio. If playback is garbled, skips, or plays as
//| static, first try using a "simpler" mp3:
//|
//| * Use constant bit rate (CBR) not VBR or ABR (variable or average bit rate) when encoding your mp3 file
//| * Use a lower sample rate (e.g., 11.025kHz instead of 48kHz)
//| * Use a lower bit rate (e.g., 32kbit/s instead of 256kbit/s)
//|
//| Reduce activity taking place at the same time as
//| mp3 playback. For instance, only update small portions of a
//| displayio screen if audio is playing. Disable auto-refresh
//| and explicitly call refresh.
//|
//| Playing a mp3 file from flash::
//|
//| import board
//| import audiomp3
//| import audioio
//| import digitalio
//|
//| # Required for CircuitPlayground Express
//| speaker_enable = digitalio.DigitalInOut(board.SPEAKER_ENABLE)
//| speaker_enable.switch_to_output(value=True)
//|
//| mp3 = audiomp3.MP3Decoder("cplay-16bit-16khz-64kbps.mp3")
//| a = audioio.AudioOut(board.A0)
//|
//| print("playing")
//| a.play(mp3)
//| while a.playing:
//| pass
//| print("stopped")
//|
//| It is possible to seek within a file before playing it::
//|
//| with open("/test.mp3", "rb") as stream:
//| stream.seek(128000 * 30 // 8) # Seek about 30s into a 128kbit/s stream
//| decoder.file = stream
//|
//| If the stream is played with ``loop = True``, the loop will start at the beginning.
//|
//| It is possible to stream an mp3 from a socket, including a secure socket.
//| The MP3Decoder may change the timeout and non-blocking status of the socket.
//| Using a larger decode buffer with a stream can be helpful to avoid data underruns.
//| An ``adafruit_requests`` request must be made with ``headers={"Connection": "close"}`` so
//| that the socket closes when the stream ends.
//| """
//| ...
//|
static mp_obj_t audiomp3_mp3file_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
mp_arg_check_num(n_args, n_kw, 1, 2, false);
mp_obj_t stream = args[0];
if (mp_obj_is_str(stream)) {
stream = mp_call_function_2(MP_OBJ_FROM_PTR(&mp_builtin_open_obj), stream, MP_ROM_QSTR(MP_QSTR_rb));
}
audiomp3_mp3file_obj_t *self = mp_obj_malloc_with_finaliser(audiomp3_mp3file_obj_t, &audiomp3_mp3file_type);
const mp_stream_p_t *stream_p = mp_get_stream_raise(stream, MP_STREAM_OP_READ);
if (stream_p->is_text) {
mp_raise_TypeError(MP_ERROR_TEXT("file must be a file opened in byte mode"));
}
uint8_t *buffer = NULL;
size_t buffer_size = 0;
if (n_args >= 2) {
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_WRITE);
buffer = bufinfo.buf;
buffer_size = bufinfo.len;
}
common_hal_audiomp3_mp3file_construct(self, stream, buffer, buffer_size);
return MP_OBJ_FROM_PTR(self);
}
//| def deinit(self) -> None:
//| """Deinitialises the MP3 and releases all memory resources for reuse."""
//| ...
//|
static mp_obj_t audiomp3_mp3file_deinit(mp_obj_t self_in) {
audiomp3_mp3file_obj_t *self = MP_OBJ_TO_PTR(self_in);
common_hal_audiomp3_mp3file_deinit(self);
return mp_const_none;
}
static MP_DEFINE_CONST_FUN_OBJ_1(audiomp3_mp3file_deinit_obj, audiomp3_mp3file_deinit);
static void check_for_deinit(audiomp3_mp3file_obj_t *self) {
audiosample_check_for_deinit(&self->base);
}
//| def __enter__(self) -> MP3Decoder:
//| """No-op used by Context Managers."""
//| ...
//|
// Provided by context manager helper.
//| def __exit__(self) -> None:
//| """Automatically deinitializes the hardware when exiting a context. See
//| :ref:`lifetime-and-contextmanagers` for more info."""
//| ...
//|
// Provided by context manager helper.
//| file: typing.BinaryIO
//| """File to play back."""
//|
static mp_obj_t audiomp3_mp3file_obj_get_file(mp_obj_t self_in) {
audiomp3_mp3file_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
return self->stream;
}
MP_DEFINE_CONST_FUN_OBJ_1(audiomp3_mp3file_get_file_obj, audiomp3_mp3file_obj_get_file);
static mp_obj_t audiomp3_mp3file_obj_set_file(mp_obj_t self_in, mp_obj_t stream) {
audiomp3_mp3file_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
const mp_stream_p_t *stream_p = mp_get_stream_raise(stream, MP_STREAM_OP_READ);
if (stream_p->is_text) {
mp_raise_TypeError(MP_ERROR_TEXT("file must be a file opened in byte mode"));
}
common_hal_audiomp3_mp3file_set_file(self, stream);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(audiomp3_mp3file_set_file_obj, audiomp3_mp3file_obj_set_file);
//| def open(self, filepath: str) -> None:
//| """Takes in the name of a mp3 file, opens it, and replaces the old playback file."""
//| ...
//|
static mp_obj_t audiomp3_mp3file_obj_open(mp_obj_t self_in, mp_obj_t path) {
audiomp3_mp3file_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
mp_obj_t file = mp_call_function_2(MP_OBJ_FROM_PTR(&mp_builtin_open_obj), path, MP_ROM_QSTR(MP_QSTR_rb));
common_hal_audiomp3_mp3file_set_file(self, file);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(audiomp3_mp3file_open_obj, audiomp3_mp3file_obj_open);
MP_PROPERTY_GETSET(audiomp3_mp3file_file_obj,
(mp_obj_t)&audiomp3_mp3file_get_file_obj,
(mp_obj_t)&audiomp3_mp3file_set_file_obj);
//| sample_rate: int
//| """32 bit value that dictates how quickly samples are loaded into the DAC
//| in Hertz (cycles per second). When the sample is looped, this can change
//| the pitch output without changing the underlying sample."""
//| bits_per_sample: int
//| """Bits per sample. (read only)"""
//| channel_count: int
//| """Number of audio channels. (read only)"""
//| rms_level: float
//| """The RMS audio level of a recently played moment of audio. (read only)"""
static mp_obj_t audiomp3_mp3file_obj_get_rms_level(mp_obj_t self_in) {
audiomp3_mp3file_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
return mp_obj_new_float(common_hal_audiomp3_mp3file_get_rms_level(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(audiomp3_mp3file_get_rms_level_obj, audiomp3_mp3file_obj_get_rms_level);
MP_PROPERTY_GETTER(audiomp3_mp3file_rms_level_obj,
(mp_obj_t)&audiomp3_mp3file_get_rms_level_obj);
//| samples_decoded: int
//| """The number of audio samples decoded from the current file. (read only)"""
//|
//|
static mp_obj_t audiomp3_mp3file_obj_get_samples_decoded(mp_obj_t self_in) {
audiomp3_mp3file_obj_t *self = MP_OBJ_TO_PTR(self_in);
check_for_deinit(self);
return MP_OBJ_NEW_SMALL_INT(common_hal_audiomp3_mp3file_get_samples_decoded(self));
}
MP_DEFINE_CONST_FUN_OBJ_1(audiomp3_mp3file_get_samples_decoded_obj, audiomp3_mp3file_obj_get_samples_decoded);
MP_PROPERTY_GETTER(audiomp3_mp3file_samples_decoded_obj,
(mp_obj_t)&audiomp3_mp3file_get_samples_decoded_obj);
static const mp_rom_map_elem_t audiomp3_mp3file_locals_dict_table[] = {
// Methods
{ MP_ROM_QSTR(MP_QSTR_open), MP_ROM_PTR(&audiomp3_mp3file_open_obj) },
{ MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&audiomp3_mp3file_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR___del__), MP_ROM_PTR(&audiomp3_mp3file_deinit_obj) },
{ MP_ROM_QSTR(MP_QSTR___enter__), MP_ROM_PTR(&default___enter___obj) },
{ MP_ROM_QSTR(MP_QSTR___exit__), MP_ROM_PTR(&default___exit___obj) },
// Properties
{ MP_ROM_QSTR(MP_QSTR_file), MP_ROM_PTR(&audiomp3_mp3file_file_obj) },
{ MP_ROM_QSTR(MP_QSTR_rms_level), MP_ROM_PTR(&audiomp3_mp3file_rms_level_obj) },
{ MP_ROM_QSTR(MP_QSTR_samples_decoded), MP_ROM_PTR(&audiomp3_mp3file_samples_decoded_obj) },
AUDIOSAMPLE_FIELDS,
};
static MP_DEFINE_CONST_DICT(audiomp3_mp3file_locals_dict, audiomp3_mp3file_locals_dict_table);
static const audiosample_p_t audiomp3_mp3file_proto = {
MP_PROTO_IMPLEMENT(MP_QSTR_protocol_audiosample)
.reset_buffer = (audiosample_reset_buffer_fun)audiomp3_mp3file_reset_buffer,
.get_buffer = (audiosample_get_buffer_fun)audiomp3_mp3file_get_buffer,
};
MP_DEFINE_CONST_OBJ_TYPE(
audiomp3_mp3file_type,
MP_QSTR_MP3Decoder,
MP_TYPE_FLAG_HAS_SPECIAL_ACCESSORS,
make_new, audiomp3_mp3file_make_new,
locals_dict, &audiomp3_mp3file_locals_dict,
protocol, &audiomp3_mp3file_proto
);
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