view vamp/collect.py @ 85:02956a88ee58

Timestamper

'''A high-level interface to the vampyhost extension module, for quickly and easily running Vamp audio analysis plugins on audio files and buffers.'''

import vampyhost
import load
import frames

##!!!
##
## We could also devise a generator for the timestamps that need
## filling: provide the output type & rate and get back a timestamp
## generator
##
##!!!

def timestamp_features(sample_rate, step_size, output_desc, features):
    n = -1
    if output_desc["sample_type"] == vampyhost.ONE_SAMPLE_PER_STEP:
        for f in features:
            n = n + 1
            t = vampyhost.frame_to_realtime(n * step_size, sample_rate)
            f["timestamp"] = t
            yield f
    elif output_desc["sample_type"] == vampyhost.FIXED_SAMPLE_RATE:
        output_rate = output_desc["sample_rate"]
        for f in features:
            if "has_timestamp" in f:
                n = int(f["timestamp"].to_float() * output_rate + 0.5)
            else:
                n = n + 1
            f["timestamp"] = vampyhost.RealTime('seconds', float(n) / output_rate)
            yield f
    else:
        for f in features:
            yield f


def collect(data, sample_rate, key, output, parameters = {}):
    
    plug, step_size, block_size = load.load_and_configure(data, sample_rate, key, parameters)

    plug_outs = plug.get_outputs()
    if plug_outs == []:
        return

    outNo = -1
    for n, o in zip(range(0, len(plug_outs)), plug_outs):
        if output == "" or o["identifier"] == output:
            outNo = n
            break

    assert outNo >= 0 #!!! todo proper error reporting

    ff = frames.frames_from_array(data, step_size, block_size)
    fi = 0

    #!!! todo!

    plug.unload()
    
    return {}