tf_models.py 文件源码

def temporal_convs_linear(n_nodes, conv_len, n_classes, n_feat, max_len, 
                        causal=False, loss='categorical_crossentropy', 
                        optimizer='adam', return_param_str=False):
    """ Used in paper: 
    Segmental Spatiotemporal CNNs for Fine-grained Action Segmentation
    Lea et al. ECCV 2016

    Note: Spatial dropout was not used in the original paper. 
    It tends to improve performance a little.  
    """

    inputs = Input(shape=(max_len,n_feat))
    if causal: model = ZeroPadding1D((conv_len//2,0))(model)
    model = Convolution1D(n_nodes, conv_len, input_dim=n_feat, input_length=max_len, border_mode='same', activation='relu')(inputs)
    if causal: model = Cropping1D((0,conv_len//2))(model)

    model = SpatialDropout1D(0.3)(model)

    model = TimeDistributed(Dense(n_classes, activation="softmax" ))(model)

    model = Model(input=inputs, output=model)
    model.compile(loss=loss, optimizer=optimizer, sample_weight_mode="temporal")

    if return_param_str:
        param_str = "tConv_C{}".format(conv_len)
        if causal:
            param_str += "_causal"

        return model, param_str
    else:
        return model