# 抓YT音樂影片且轉成mp3 （Python）- 2022

## 2022
這次回頭發現 PyTube 可以直接提取音訊
細節基本參考[Download Video in MP3 format using PyTube(GeeksforGeeks)](https://www.geeksforgeeks.org/download-video-in-mp3-format-using-pytube/)再做修改

首先安裝pytube

pip3 install pytube

::: warning
如果出現 ```ModuleNotFoundError: No module named 'pip'```
就去更新pip
執行 ``` sudo apt-get install python3-pip ```
:::

以下程式可直接取用 , 更改你的yt網址跟存mp3位置即可

from pytube import YouTube
import os
  
url = "https://www.youtube.com/watch?v=Dm9dUfvVhrQ"
target_path = "./Downloads"

yt = YouTube(url)

video = yt.streams.filter(only_audio=True).first()

out_file = video.download(output_path=target_path)

base, ext = os.path.splitext(out_file)
new_file = base + '.mp3'
os.rename(out_file, new_file)

print("target path = " + (new_file))
print("mp3 has been successfully downloaded.")

url就是你要下載的youtube mp3 網址
target_path就是下載完要放的位址
執行完如下

資料夾內對應生成mp3

:::info
\==================
以下是 2020 版本 , 可跳過
\==================
:::

## 2020
基本是參考[ccs96307大所寫的：Python 當中使用 pytube 下載 Youtube 的影片](https://clay-atlas.com/blog/2019/11/08/python-chinese-packages-pytube-moviepy-download-youtube-convert/)
不過當中遇到一些問題，紀錄如何解決。

環境:Ubuntu 18.04
使用pytube+moviepy
先安裝

sudo pip3 install pytube3
sudo pip3 install moviepy

要做的事情:
1. 抓YT影片
2. mp4轉檔mp3

### 1.抓YT影片

# -*- coding: utf-8 -*-
from pytube import YouTube
def progress(chunk,file_handle,bytes_remaining):
	contentSize=video.filesize
	size=contentSize-bytes_remaining
	print('\r' + '[Download progress]:%.2f%%;\n' % (' ' * int(size*20/contentSize), ' '*(20-int(size*20/contentSize)), float(size/contentSize*100)), end='')
url='https://www.youtube.com/watch?v=9Sc-ir2UwGU'
yt=YouTube(url,on_progress_callback=progress)
video=yt.streams.first()
video.download()

url內就放你要抓的影片網址 progress內只是顯示進度條，要簡單的話三行就能搞定

# -*- coding: utf-8 -*-
from pytube import YouTube
url = 'https://www.youtube.com/watch?v=JwBXgJeqeOs'
YouTube(url).streams.first().download()

- 配合txt存網址列表可一次抓多首
- 可搭配音樂清單一次全抓
#### 遇到問題

Traceback (most recent call last):
  File "/home/brad/.local/lib/python3.6/site-packages/pytube/extract.py", line 297, in apply_descrambler
    for format_item in formats
  File "/home/brad/.local/lib/python3.6/site-packages/pytube/extract.py", line 297, in <listcomp>
    for format_item in formats
KeyError: 'url'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "DlYT2mp3.py", line 12, in <module>
    yt=YouTube(url,on_progress_callback=progress)
  File "/home/brad/.local/lib/python3.6/site-packages/pytube/__main__.py", line 92, in __init__
    self.descramble()
  File "/home/brad/.local/lib/python3.6/site-packages/pytube/__main__.py", line 132, in descramble
    apply_descrambler(self.player_config_args, fmt)
  File "/home/brad/.local/lib/python3.6/site-packages/pytube/extract.py", line 301, in apply_descrambler
    parse_qs(formats[i]["cipher"]) for i, data in enumerate(formats)
  File "/home/brad/.local/lib/python3.6/site-packages/pytube/extract.py", line 301, in <listcomp>
    parse_qs(formats[i]["cipher"]) for i, data in enumerate(formats)
KeyError: 'cipher'

#### 如何解決？
爬文發現不少人有相同問題且有人給出解法
簡單來說就是先看你的pytube裝在哪？ 去資料夾內打開extract.py檔 找到函式apply_descrambler的301行，然後把

parse_qs(formats[i]["cipher"]) for i, data in enumerate(formats)

改成

parse_qs(formats[i]["signatureCipher"]) for i, data in enumerate(formats)

- c記得改大寫

#### 詳細步驟
1. 輸入pip3 show pytube3
看location位置在哪，進該目錄
看到pytube資料夾，進去
發現extract. py 用你的IDE打開他,找到301行 改掉
解決

### 2.mp4轉檔mp3

# -*- coding:utf-8 -*-
from moviepy.editor import *
filename='Kygo - Firestone.mp4'
targetname='Kygo - Firestone.mp3'
video=VideoFileClip(filename)
video.audio.write_audiofile(targetname)

#### 遇到問題

Traceback (most recent call last):
  File "mp4tomp3.py", line 2, in <module>
    from moviepy.editor import *
  File "/usr/local/lib/python3.6/dist-packages/moviepy/editor.py", line 36, in <module>
    from .video.io.VideoFileClip import VideoFileClip
  File "/usr/local/lib/python3.6/dist-packages/moviepy/video/io/VideoFileClip.py", line 3, in <module>
    from moviepy.audio.io.AudioFileClip import AudioFileClip
  File "/usr/local/lib/python3.6/dist-packages/moviepy/audio/io/AudioFileClip.py", line 3, in <module>
    from moviepy.audio.AudioClip import AudioClip
  File "/usr/local/lib/python3.6/dist-packages/moviepy/audio/AudioClip.py", line 7, in <module>
    from moviepy.audio.io.ffmpeg_audiowriter import ffmpeg_audiowrite
  File "/usr/local/lib/python3.6/dist-packages/moviepy/audio/io/ffmpeg_audiowriter.py", line 7, in <module>
    from moviepy.config import get_setting
  File "/usr/local/lib/python3.6/dist-packages/moviepy/config.py", line 36, in <module>
    FFMPEG_BINARY = get_exe()
  File "/usr/local/lib/python3.6/dist-packages/imageio/plugins/ffmpeg.py", line 49, in get_exe
    return imageio_ffmpeg.get_ffmpeg_exe()
  File "/usr/local/lib/python3.6/dist-packages/imageio_ffmpeg/_utils.py", line 50, in get_ffmpeg_exe
    "No ffmpeg exe could be found. Install ffmpeg on your system, "
RuntimeError: No ffmpeg exe could be found. Install ffmpeg on your system, or set the IMAGEIO_FFMPEG_EXE environment variable.

找不到ffmpeg.exe? 那就裝吧
#### 如何解決?

sudo apt update
sudo apt install ffmpeg

解決