def online_frame_generator():
""" generate signal frames from mic """
from madmom.audio.signal import Stream
hop_size = int(SAMPLE_RATE / FPS)
stream = Stream(sample_rate=SAMPLE_RATE,
num_channels=1,
frame_size=FRAME_SIZE,
hop_size=hop_size,
queue_size=1)
for frame in stream:
yield frame
def process_online(processor, infile, outfile, **kwargs):
"""Process a file or audio stream with the given Processor.
Parameters
----------
processor : :class:`Processor` instance
Processor to be processed.
infile : str or file handle, optional
Input file (handle). If none is given, the stream present at the
system's audio inpup is used. Additional keyword arguments can be used
to influence the frame size and hop size.
outfile : str or file handle
Output file (handle).
kwargs : dict, optional
Keyword arguments passed to :class:`.audio.signal.Stream` if
`in_stream` is 'None'.
Notes
-----
Right now there is no way to determine if a processor is
online-capable or not. Thus, calling any processor with this
function may not produce the results expected.
"""
from madmom.audio.signal import Stream, FramedSignal
# set default values
kwargs['sample_rate'] = kwargs.get('sample_rate', 44100)
kwargs['num_channels'] = kwargs.get('num_channels', 1)
# if no iput file is given, create a Stream with the given arguments
if infile is None:
# open a stream and start if not running already
stream = Stream(**kwargs)
if not stream.is_running():
stream.start()
# use the input file
else:
# set parameters for opening the file
frame_size = kwargs.get('frame_size', 2048)
hop_size = kwargs.get('hop_size', 441)
fps = kwargs.get('fps')
num_channels = kwargs.get('num_channels')
# FIXME: overwrite the frame size with the maximum value of all used
# processors. This is needed if multiple frame sizes are used
import warnings
warnings.warn('make sure that the `frame_size` (%d) is equal to the '
'maximum value used by any `FramedSignalProcessor`.' %
frame_size)
# Note: origin must be 'online' and num_frames 'None' to behave exactly
# the same as with live input
stream = FramedSignal(infile,
frame_size=frame_size, hop_size=hop_size,
fps=fps, origin='online', num_frames=None,
num_channels=num_channels)
# set arguments for online processing
# Note: pass only certain arguments, because these will be passed to the
# processors at every time step (kwargs contains file handles etc.)
process_args = {'reset': False} # do not reset stateful processors
# process everything frame-by-frame
for frame in stream:
_process((processor, frame, outfile, process_args))