Chris@56: '''A high-level interface to the vampyhost extension module, for quickly and easily running Vamp audio analysis plugins on audio files and buffers.'''
Chris@56: 
Chris@56: import vampyhost
Chris@56: import numpy
Chris@56: 
Chris@56: def listPlugins():
Chris@56:     return vampyhost.listPlugins()
Chris@56: 
Chris@56: def framesFromArray(arr, stepSize, frameSize):
Chris@56:     """Generate a list of frames of size frameSize, extracted from the input array arr at stepSize intervals"""
Chris@56:     # presumably such a function exists in many places, but I need practice
Chris@56:     assert(stepSize > 0)
Chris@56:     if arr.ndim == 1: # turn 1d into 2d array with 1 channel
Chris@56:         arr = numpy.reshape(arr, (1, arr.shape[0]))
Chris@56:     assert(arr.ndim == 2)
Chris@56:     n = arr.shape[1]
Chris@56:     i = 0
Chris@56:     while (i < n):
Chris@56:         frame = arr[:, i : i + frameSize]
Chris@56:         w = frame.shape[1]
Chris@56:         if (w < frameSize):
Chris@56:             pad = numpy.zeros((frame.shape[0], frameSize - w))
Chris@56:             frame = numpy.concatenate((frame, pad), 1)
Chris@56:         yield frame
Chris@56:         i = i + stepSize
Chris@56: 
Chris@61: def selectOutputs(result, outputs):
Chris@61:     return result ##!!! for now
Chris@61: 
Chris@56: def process(data, samplerate, key, parameters, outputs):
Chris@58:     plug = vampyhost.loadPlugin(key, samplerate,
Chris@58:                                 vampyhost.AdaptInputDomain +
Chris@58:                                 vampyhost.AdaptChannelCount)
Chris@56:     stepSize = plug.getPreferredStepSize()
Chris@56:     blockSize = plug.getPreferredBlockSize()
Chris@61:     if blockSize == 0:
Chris@61:         blockSize = 1024
Chris@61:     if stepSize == 0:
Chris@61:         stepSize = blockSize ##!!! or blockSize/2, but check this with input domain adapter
Chris@61:     channels = 1
Chris@61:     if data.ndim > 1:
Chris@61:         channels = data.shape[0]
Chris@61:     plug.initialise(channels, stepSize, blockSize)
Chris@56:     ff = framesFromArray(data, stepSize, blockSize)
Chris@61:     fi = 0
Chris@61:     for f in ff:
Chris@61:         result = plug.processBlock(f, vampyhost.frame2RealTime(fi, samplerate))
Chris@61:         yield selectOutputs(result, outputs)
Chris@61:         fi = fi + stepSize
Chris@61: