mirror of
https://github.com/markqvist/Sideband.git
synced 2024-12-29 09:26:20 -05:00
111 lines
3.2 KiB
Python
111 lines
3.2 KiB
Python
import ctypes
|
|
|
|
from . import vorbis
|
|
from .pyogg_error import PyOggError
|
|
|
|
class VorbisFileStream:
|
|
def __init__(self, path, buffer_size=8192):
|
|
self.exists = False
|
|
self._buffer_size = buffer_size
|
|
|
|
self.vf = vorbis.OggVorbis_File()
|
|
error = vorbis.ov_fopen(path, ctypes.byref(self.vf))
|
|
if error != 0:
|
|
raise PyOggError("file couldn't be opened or doesn't exist. Error code : {}".format(error))
|
|
|
|
info = vorbis.ov_info(ctypes.byref(self.vf), -1)
|
|
|
|
#: Number of channels in audio file.
|
|
self.channels = info.contents.channels
|
|
|
|
#: Number of samples per second (per channel). Always
|
|
# 48,000.
|
|
self.frequency = info.contents.rate
|
|
|
|
array = (ctypes.c_char*(self._buffer_size*self.channels))()
|
|
|
|
self.buffer_ = ctypes.cast(ctypes.pointer(array), ctypes.c_char_p)
|
|
|
|
self.bitstream = ctypes.c_int()
|
|
self.bitstream_pointer = ctypes.pointer(self.bitstream)
|
|
|
|
self.exists = True # TODO: is this the best place for this statement?
|
|
|
|
#: Bytes per sample
|
|
self.bytes_per_sample = 2 # TODO: Where is this defined?
|
|
|
|
def __del__(self):
|
|
if self.exists:
|
|
vorbis.ov_clear(ctypes.byref(self.vf))
|
|
self.exists = False
|
|
|
|
def clean_up(self):
|
|
vorbis.ov_clear(ctypes.byref(self.vf))
|
|
|
|
self.exists = False
|
|
|
|
def get_buffer(self):
|
|
"""get_buffer() -> bytesBuffer, bufferLength
|
|
|
|
Returns None when all data has been read from the file.
|
|
|
|
"""
|
|
if not self.exists:
|
|
return None
|
|
buffer = []
|
|
total_bytes_written = 0
|
|
|
|
while True:
|
|
new_bytes = vorbis.ov_read(ctypes.byref(self.vf), self.buffer_, self._buffer_size*self.channels - total_bytes_written, 0, 2, 1, self.bitstream_pointer)
|
|
|
|
array_ = ctypes.cast(self.buffer_, ctypes.POINTER(ctypes.c_char*(self._buffer_size*self.channels))).contents
|
|
|
|
buffer.append(array_.raw[:new_bytes])
|
|
|
|
total_bytes_written += new_bytes
|
|
|
|
if new_bytes == 0 or total_bytes_written >= self._buffer_size*self.channels:
|
|
break
|
|
|
|
out_buffer = b"".join(buffer)
|
|
|
|
if total_bytes_written == 0:
|
|
self.clean_up()
|
|
return(None)
|
|
|
|
return out_buffer
|
|
|
|
def get_buffer_as_array(self):
|
|
"""Provides the buffer as a NumPy array.
|
|
|
|
Note that the underlying data type is 16-bit signed
|
|
integers.
|
|
|
|
Does not copy the underlying data, so the returned array
|
|
should either be processed or copied before the next call
|
|
to get_buffer() or get_buffer_as_array().
|
|
|
|
"""
|
|
import numpy # type: ignore
|
|
|
|
# Read the next samples from the stream
|
|
buf = self.get_buffer()
|
|
|
|
# Check if we've come to the end of the stream
|
|
if buf is None:
|
|
return None
|
|
|
|
# Convert the bytes buffer to a NumPy array
|
|
array = numpy.frombuffer(
|
|
buf,
|
|
dtype=numpy.int16
|
|
)
|
|
|
|
# Reshape the array
|
|
return array.reshape(
|
|
(len(buf)
|
|
// self.bytes_per_sample
|
|
// self.channels,
|
|
self.channels)
|
|
)
|