class TextTransform:
    """Maps characters to integers and vice versa"""
    def __init__(self):
        char_map_str = """
        ' 0
        <space> 1
        a 2
        b 3
        c 4
        d 5
        e 6
        f 7
        g 8
        h 9
        i 10
        j 11
        k 12
        l 13
        m 14
        n 15
        o 16
        p 17
        q 18
        r 19
        s 20
        t 21
        u 22
        v 23
        w 24
        x 25
        y 26
        z 27
        """
        self.char_map = {}
        self.index_map = {}
        for line in char_map_str.strip().split('\n'):
            ch, index = line.split()
            self.char_map[ch] = int(index)
            self.index_map[int(index)] = ch
        self.index_map[1] = ' '

# 文字轉數字
def text_to_int(self, text):
    """ Use a character map and convert text to an integer sequence """
    int_sequence = []
    for c in text:
        if c == ' ':
            ch = self.char_map['<space>']
        else:
            ch = self.char_map[c]
        int_sequence.append(ch)
    return int_sequence
# 數字轉文字
def int_to_text(self, labels):
    """ Use a character map and convert integer labels to an text sequence """
    string = []
    for i in labels:
        string.append(self.index_map[i])
    return ''.join(string)

filelist = os.listdir(path)
for filename in (filelist):
    file_path = os.path.join(path, filename)
    y, sr = librosa.load(file_path)
    duration = librosa.get_duration(y, sr)
    # 刪除長度超過30秒之音檔
    if duration > 30:
        filepath = os.path.join(path, filename)
        os.remove(filepath)

"n_cnn_layers": 3
"n_rnn_layers": 7
"rnn_dim": 1024
"n_class": 29
"n_feats": 128
"stride": 2
"dropout": 0.1

learning_rate =  5e-4
batch_size = 20
epochs = 100