def self_attention(x, NUM_FILTER=32): N = int(NUM_FILTER / 8) f = Conv1D(filters = N, kernel_size = 1, adding = 'same')(x) g = Conv1D(filters = N, kernel_size = 1, padding = 'same')(x) h = Conv1D(filters = NUM_FILTER, kernel_size = 1, padding = 'same')(x) f_trans = Permute([2, 1])(f) energy = Lambda(lambda x: K.batch_dot(x[0], x[1]))([g, f_trans]) attention = Activation('softmax')(energy) out = Lambda(lambda x: K.batch_dot(x[0], x[1]))([attention, h]) # out = Conv1D(filters = NUM_FILTER, kernel_size = 1, padding = 'same')(out) out = Combination()([out, x]) return out

这段代码是一个实现自注意力机制的函数`self_attention`，函数接受一个`x`作为输入，以及一个可选的参数`NUM_FILTER`，默认为32。函数的作用是对输入`x`进行一维卷积操作，并在卷积后的特征表示上引入自注意力机制，从而提取输入特征的关键信息。

具体来说，`self_attention`函数的实现包括以下几个步骤：

1. 将`NUM_FILTER`除以8得到一个整数`N`。

2. 使用Keras的Conv1D函数对输入变量`x`进行三次一维卷积操作，得到三个特征表示矩阵，分别为`f`、`g`和`h`。

3. 将`f`矩阵进行转置，得到一个新的矩阵`f_trans`。

4. 使用Lambda函数和Keras的batch_dot函数计算`g`矩阵和`f_trans`矩阵的乘积，得到一个注意力能量矩阵`energy`。

5. 使用Activation函数和softmax激活函数将`energy`矩阵进行归一化，得到注意力权重矩阵`attention`。

6. 使用Lambda函数和Keras的batch_dot函数计算`attention`矩阵和`h`矩阵的加权和，得到最终的特征表示矩阵`out`。

7. 使用Combination层将`out`矩阵和输入变量`x`进行加权相加，得到最终的输出特征表示。

需要注意的是，这段代码中的具体实现可能与不同的上下文和应用场景有关，因此需要结合具体的代码和文档进行理解和使用。

相关问题

下面给出一段详细代码：class CrnModel: def init(self, feature_num): self.feature_num = feature_num self.input_magnitude = layers.Input(shape=[128, feature_num], name='input_magnitude') model_output = self.structure_model() self.model = tf.keras.Model(inputs=self.input_magnitude, outputs=model_output) self.model.summary() def structure_model(self): layer_input = self.input_magnitude layer_output = layers.Conv1D(filters=64, padding='causal', dilation_rate=1, kernel_size=3, activation='relu')( layer_input) layer_output = layers.Conv1D(filters=64, padding='causal', dilation_rate=2, kernel_size=3, activation='relu')( layer_output) layer_output = layers.Conv1D(filters=64, padding='causal', dilation_rate=4, kernel_size=3, activation='relu')( layer_output) layer_output = layers.Conv1D(filters=64, kernel_size=1, activation='linear')(layer_output) layer_output = layers.Conv1D(filters=257, kernel_size=1, activation='relu')(layer_output) return layer_output。请你给出详细解释和注释

这是一个使用 TensorFlow 实现的 CRN（Causal Residual Network）模型，用于音频信号处理。下面是对代码的详细注释：

class CrnModel:
    def __init__(self, feature_num):
        self.feature_num = feature_num   # 初始化类的特征数
        self.input_magnitude = layers.Input(shape=[128, feature_num], name='input_magnitude')  # 定义输入层，输入维度为 [128, feature_num]
        model_output = self.structure_model()  # 定义模型输出
        self.model = tf.keras.Model(inputs=self.input_magnitude, outputs=model_output)  # 定义完整模型
        self.model.summary()  # 打印模型概述

    def structure_model(self):
        layer_input = self.input_magnitude  # 定义输入层
        layer_output = layers.Conv1D(filters=64, padding='causal', dilation_rate=1, kernel_size=3, activation='relu')(layer_input)  # 第一层卷积层
        layer_output = layers.Conv1D(filters=64, padding='causal', dilation_rate=2, kernel_size=3, activation='relu')(layer_output)  # 第二层卷积层
        layer_output = layers.Conv1D(filters=64, padding='causal', dilation_rate=4, kernel_size=3, activation='relu')(layer_output)  # 第三层卷积层
        layer_output = layers.Conv1D(filters=64, kernel_size=1, activation='linear')(layer_output)  # 用 1x1 卷积层降维
        layer_output = layers.Conv1D(filters=257, kernel_size=1, activation='relu')(layer_output)  # 最终输出层，输出维度为 257
        return layer_output  # 返回最终输出层

该模型使用了四个卷积层，其中 dilation_rate 表示膨胀率，padding 表示填充方式，kernel_size 表示卷积核大小，filters 表示卷积核数量，activation 表示激活函数。模型输入维度为 [128, feature_num]，输出维度为 [128, 257]，其中 257 表示频域的维度。最后使用 Keras 的 Model 类定义完整模型，并打印模型概述。

def model(self): num_classes = self.config.get("CNN_training_rule", "num_classes") seq_length = self.config.get("CNN_training_rule", "seq_length") conv1_num_filters = self.config.get("CNN_training_rule", "conv1_num_filters") conv1_kernel_size = self.config.get("CNN_training_rule", "conv1_kernel_size") conv2_num_filters = self.config.get("CNN_training_rule", "conv2_num_filters") conv2_kernel_size = self.config.get("CNN_training_rule", "conv2_kernel_size") hidden_dim = self.config.get("CNN_training_rule", "hidden_dim") dropout_keep_prob = self.config.get("CNN_training_rule", "dropout_keep_prob") model_input = keras.layers.Input((seq_length,1), dtype='float64') # conv1形状[batch_size, seq_length, conv1_num_filters] conv_1 = keras.layers.Conv1D(conv1_num_filters, conv1_kernel_size, padding="SAME")(model_input) conv_2 = keras.layers.Conv1D(conv2_num_filters, conv2_kernel_size, padding="SAME")(conv_1) max_poolinged = keras.layers.GlobalMaxPool1D()(conv_2) full_connect = keras.layers.Dense(hidden_dim)(max_poolinged) droped = keras.layers.Dropout(dropout_keep_prob)(full_connect) relued = keras.layers.ReLU()(droped) model_output = keras.layers.Dense(num_classes, activation="softmax")(relued) model = keras.models.Model(inputs=model_input, outputs=model_output) # model.compile(loss="categorical_crossentropy", # optimizer="adam", # metrics=["accuracy"]) model.compile(loss='binary_crossentropy', optimizer='adam', metrics=['accuracy']) print(model.summary()) return model给这段代码每行加上注释

def model(self):
    # 获取配置文件中的参数
    num_classes = self.config.get("CNN_training_rule", "num_classes") #分类数
    seq_length = self.config.get("CNN_training_rule", "seq_length") #序列长度
    conv1_num_filters = self.config.get("CNN_training_rule", "conv1_num_filters") #第一层卷积核数量
    conv1_kernel_size = self.config.get("CNN_training_rule", "conv1_kernel_size") #第一层卷积核大小
    conv2_num_filters = self.config.get("CNN_training_rule", "conv2_num_filters") #第二层卷积核数量
    conv2_kernel_size = self.config.get("CNN_training_rule", "conv2_kernel_size") #第二层卷积核大小
    hidden_dim = self.config.get("CNN_training_rule", "hidden_dim") #全连接层隐藏层大小
    dropout_keep_prob = self.config.get("CNN_training_rule", "dropout_keep_prob") #dropout保留率

    # 定义模型输入
    model_input = keras.layers.Input((seq_length,1), dtype='float64')

    # 第一层卷积
    conv_1 = keras.layers.Conv1D(conv1_num_filters, conv1_kernel_size, padding="SAME")(model_input)

    # 第二层卷积
    conv_2 = keras.layers.Conv1D(conv2_num_filters, conv2_kernel_size, padding="SAME")(conv_1)

    # 全局最大池化
    max_poolinged = keras.layers.GlobalMaxPool1D()(conv_2)

    # 全连接层
    full_connect = keras.layers.Dense(hidden_dim)(max_poolinged)

    # dropout层
    droped = keras.layers.Dropout(dropout_keep_prob)(full_connect)

    # relu激活层
    relued = keras.layers.ReLU()(droped)

    # 输出层
    model_output = keras.layers.Dense(num_classes, activation="softmax")(relued)

    # 定义模型
    model = keras.models.Model(inputs=model_input, outputs=model_output)

    # 编译模型
    model.compile(loss='binary_crossentropy',
                  optimizer='adam',
                  metrics=['accuracy'])

    # 打印模型结构
    print(model.summary())

    return model