python实现视频转文字

最近在做视频转文本的工作，遇到了不少问题，记录一下。
本博客包括以下内容：
1.如何将视频转换成音频
2.如何调用科大讯飞API实现音频转文字
首先，视频转文本，如果调用科大讯飞API的话，那么是需要先将视频提取成音频，这里很简单，python几行代码就可以搞定。

from moviepy.editor import AudioFileClip

my=AudioFileClip("myvideo.mp4") # 你的视频地址
my.write_audiofile("my.mp3") # 设置生成的音频

安装moviepy即可，建议使用conda。运行没问题那么恭喜你！

如果出现和我类似的问题，请看下文：

网上这个问题似乎很少，出现这个问题，建议先检查自己的anaconda是否曾多次安装，但之前的环境变量没有更改。
其次，检查自己的环境变量是否如下，少了就添加
如果还是有问题，打开anaconda prompt,将numpy重新卸载安装，可能是numpy版本冲突了。

conda uninstall numpy

conda install numpy

再去运行一下，会发现之前no module named "numpy.typing"没有了。如果你运气好，到这一步就会成功生成音频文件。不得不说，有时候改bug就是玄学。
另外，如果是刚入坑的同学，切记环境变量不要写中文，否则很多包调用的时候都会出问题。
成功以后：

接着我们可以看到已经生成了完整的音频文件
完成视频转音频，那就可以继续转文字。记得去注册一个科大讯飞的账号，可以免费使用一小段时间。
科大讯飞：科大讯飞
![请添加图片描述](https://img-blog.csdnimg.cn/80ae785ad73d44a6a3c796de286e6154.png
申请成功以后复制自己的id和secret即可。

# -*- coding: utf-8 -*-

import base64
import hashlib
import hmac
import json
import os
import time
import re
import requests
from moviepy.editor import AudioFileClip

my=AudioFileClip("myvideo.mp4")
my.write_audiofile("my.mp3")

lfasr_host = 'http://raasr.xfyun.cn/api'

api_prepare = '/prepare'
api_upload = '/upload'
api_merge = '/merge'
api_get_progress = '/getProgress'
api_get_result = '/getResult'
file_piece_sice = 10485760

lfasr_type = 0
has_participle = 'false'
has_seperate = 'true'
max_alternatives = 0
suid = ''


class SliceIdGenerator:
    """slice id生成器"""

    def __init__(self):
        self.__ch = 'aaaaaaaaa`'

    def getNextSliceId(self):
        ch = self.__ch
        j = len(ch) - 1
        while j >= 0:
            cj = ch[j]
            if cj != 'z':
                ch = ch[:j] + chr(ord(cj) + 1) + ch[j + 1:]
                break
            else:
                ch = ch[:j] + 'a' + ch[j + 1:]
                j = j - 1
        self.__ch = ch
        return self.__ch


class RequestApi(object):
    def __init__(self, appid, secret_key, upload_file_path):
        self.appid = appid
        self.secret_key = secret_key
        self.upload_file_path = upload_file_path

    def gene_params(self, apiname, taskid=None, slice_id=None):
        appid = self.appid
        secret_key = self.secret_key
        upload_file_path = self.upload_file_path
        ts = str(int(time.time()))
        m2 = hashlib.md5()
        m2.update((appid + ts).encode('utf-8'))
        md5 = m2.hexdigest()
        md5 = bytes(md5, encoding='utf-8')
        
        signa = hmac.new(secret_key.encode('utf-8'), md5, hashlib.sha1).digest()
        signa = base64.b64encode(signa)
        signa = str(signa, 'utf-8')
        file_len = os.path.getsize(upload_file_path)
        file_name = os.path.basename(upload_file_path)
        param_dict = {}

        if apiname == api_prepare:
            slice_num = int(file_len / file_piece_sice) + (0 if (file_len % file_piece_sice == 0) else 1)
            param_dict['app_id'] = appid
            param_dict['signa'] = signa
            param_dict['ts'] = ts
            param_dict['file_len'] = str(file_len)
            param_dict['file_name'] = file_name
            param_dict['slice_num'] = str(slice_num)
        elif apiname == api_upload:
            param_dict['app_id'] = appid
            param_dict['signa'] = signa
            param_dict['ts'] = ts
            param_dict['task_id'] = taskid
            param_dict['slice_id'] = slice_id
        elif apiname == api_merge:
            param_dict['app_id'] = appid
            param_dict['signa'] = signa
            param_dict['ts'] = ts
            param_dict['task_id'] = taskid
            param_dict['file_name'] = file_name
        elif apiname == api_get_progress or apiname == api_get_result:
            param_dict['app_id'] = appid
            param_dict['signa'] = signa
            param_dict['ts'] = ts
            param_dict['task_id'] = taskid
        return param_dict

    def gene_request(self, apiname, data, files=None, headers=None):
        response = requests.post(lfasr_host + apiname, data=data, files=files, headers=headers)
        result = json.loads(response.text)
        if result["ok"] == 0:
            if apiname=='/getResult':
                results=re.findall(r"\"onebest\":\"(.+?)\",",result['data'])
                print(results)
                upload_file_path = self.upload_file_path
                with open(str(upload_file_path)+".txt", "a", encoding='utf-8') as f:
                    for i in results:
                        f.write(i)
            print("{} success:".format(apiname) + str(result))
            return result
        else:
            print("{} error:".format(apiname) + str(result))
            exit(0)
            return result

    def prepare_request(self):
        return self.gene_request(apiname=api_prepare,
                                 data=self.gene_params(api_prepare))

    def upload_request(self, taskid, upload_file_path):
        file_object = open(upload_file_path, 'rb')
        try:
            index = 1
            sig = SliceIdGenerator()
            while True:
                content = file_object.read(file_piece_sice)
                if not content or len(content) == 0:
                    break
                files = {
                    "filename": self.gene_params(api_upload).get("slice_id"),
                    "content": content
                }
                response = self.gene_request(api_upload,
                                             data=self.gene_params(api_upload, taskid=taskid,
                                                                   slice_id=sig.getNextSliceId()),
                                             files=files)
                if response.get('ok') != 0:
                    print('upload slice fail, response: ' + str(response))
                    return False
                print('upload slice ' + str(index) + ' success')
                index += 1
        finally:
            'file index:' + str(file_object.tell())
            file_object.close()
        return True

    def merge_request(self, taskid):
        return self.gene_request(api_merge, data=self.gene_params(api_merge, taskid=taskid))

    def get_progress_request(self, taskid):
        return self.gene_request(api_get_progress, data=self.gene_params(api_get_progress, taskid=taskid))

    def get_result_request(self, taskid):
        return self.gene_request(api_get_result, data=self.gene_params(api_get_result, taskid=taskid))

    def all_api_request(self):
        pre_result = self.prepare_request()
        taskid = pre_result["data"]
        self.upload_request(taskid=taskid, upload_file_path=self.upload_file_path)
        self.merge_request(taskid=taskid)
        while True：
            progress = self.get_progress_request(taskid)
            progress_dic = progress
            if progress_dic['err_no'] != 0 and progress_dic['err_no'] != 26605:
                print('task error: ' + progress_dic['failed'])
                return
            else:
                data = progress_dic['data']
                task_status = json.loads(data)
                if task_status['status'] == 9:
                    print('task ' + taskid + ' finished')
                    break
                print('The task ' + taskid + ' is in processing, task status: ' + str(data))
            time.sleep(20)
        self.get_result_request(taskid=taskid)
        
if __name__ == '__main__':
	# 这里记得输入自己的id和key
    api = RequestApi(appid="***", secret_key="***", upload_file_path=r"my.mp3")
    api.all_api_request()

成功后：
生成的txt文件