python常用工具

读取和生成json文件

from json import load,dumps


# 读取json文件
def read_json(file_path):
    file_json = None
    try:
        with open(file_path, mode='r', encoding="utf-8") as f:
            file_json = load(f)
    except Exception as e:
        print(f"read json error:{e}")
    finally:
        return file_json

# 生成json文件
def generate_json(content_dic,file_path):
    try:
        with open(file_path, "w", encoding="utf-8") as f:
            f.write(dumps(content_dic, indent=4, ensure_ascii=False))
    except Exception as e:
        print(f"generate json error:{e}")

读取和生成csv文件

import csv
csv.field_size_limit(500 * 1024 * 1024)

def read_csv(file_path):
    try:
        with open(file_path, "rb") as f:
            # 这里reader是一个生成器
            content = csv.reader(f)
            for row in content:
                return row
    except Exception as e:
        print(f"read csv error:{e}")


def generate_csv(file_path, content: tuple):
    try:
        with open(file_path, "wb",newline='',encoding='cp936') as f:
            # 使用python的csv生成excel所兼容的csv文件，设置参数dialect="excel"
            write = csv.writer(f, dialect="excel")
            write.writerow(content)
    except Exception as e:
        print(f"generate csv error:{e}")

创建和读取exceL

import xlwt
import openpyxl as px

# 创建excel,并创建sheet
def creat_excel():
    # 新建workbook
    workbook = xlwt.Workbook()
    # 新建worksheet
    sheet = workbook.add_sheet("data")

    # 添加边框
    borders = xlwt.Borders()
    borders.left = xlwt.Borders.THIN
    borders.right = xlwt.Borders.THIN
    borders.top = xlwt.Borders.THIN
    borders.bottom = xlwt.Borders.THIN
    font = xlwt.Font()
    font.height = 20 * 11
    style = xlwt.XFStyle()
    style.borders = borders
    style.font = font
    return workbook, sheet, style

# 创建excel,并创建sheet
def creat_excel():
    book = px.Workbook()
    sheet = book.active
    return book, sheet


# 主程序
def generate_excel(content_list, output_file):
    book, sheet = creat_excel()
    try:
        sheet.append(["歌曲文件名", "歌词文件名"])
        for content in content_list:
            sheet.append(content)
        book.save(output_file)
    except Exception as e:
        logger.error(f"生成excel失败:{e}")
        book.close()



def load_excel(excel_path):
    try:
        open_excel = px.load_workbook(excel_path)
        sheet = open_excel.worksheets[0]
        return sheet
    except Exception as e:
        print(f"{excel_path}:load_excel error:{e}")

def read_excel(excel_path):
    sheet = load_excel(excel_path)
    for row in range(2, sheet.max_row + 1):
        data = sheet.cell(row, 1).value

捕获异常

    try:
        main(csv_file, input_folder, result_folder)
        print("Finished...")
    except Exception as e:
        import traceback

        print(f"程序运行失败！！！请联系数据处理中心:{e}")
        print(traceback.format_exc())
    system("pause")

获取视频时长

def get_video_duration(filename):
    """
    获取视频文件时长
    """
    cap = cv2.VideoCapture(str(filename))
    if cap.isOpened():
        rate = cap.get(5)
        frame_num = cap.get(7)
        duration = frame_num / rate
        return duration
    return -1

pydub

form pydub import AudioSegment

将音频读为一个对象进行处理

• 音频读取

audio_obj = AudioSegment.from_file('wavpath')

• 音频时长获取

  • len(audio_obj) 结果为ms
  • audio_obj.duration_seconds

• 音频声道数

  • L，R = wav.split_to_mono() 立体声抽取单声道
  • 合并单声道为立体声，也可合并多个单声道()

  AudioSegment.from_mono_audiosegments(1, 2, 3, 4) 
  

• 音频参数修改

  • AudioSegment.from_file(str(src_file)).set_frame_rate(16000) 设置音频采样率（降采样）
  • set_sample_width 设置音频位宽
  • set_channels 设置通道数（仅支持单通道和双通道之间转换）

• 音频标准化

db = wav.max_dBFS
normalized_sound = wav.apply_gain(-6.0-db) # 音频在-6db范围标准化

• 音频拼接

# 构建静音段
silence = AudioSegment.silent(100, wav.frame_rate)
# 实例化空白音频，并将静音段和正常的段拼接追加到空白音频中
new_wav = silence + wav + silence

• 音频截取

st = int(pa['hdTimeStart'] * 1000)
ed = int(pa['hdTimeEnd'] * 1000)
new_wav = wav[st:ed]
new_wav.export(path, format='wav')

opencv读取保存包含中文路径的图片

image_mask = cv2.imdecode(np.fromfile(src_jpg_image, dtype=np.uint8), cv2.IMREAD_UNCHANGED)
dst_gray_image = "output.png"
cv2.imencode('.png', image_mask)[1].tofile(dst_gray_image)