pytube項目
最近我家姑娘的幼兒園外教需要一整套YouTube的教學兒歌《Singing Walrus Music》，在家長羣裏發出求助後，作爲程序員的老爸必須把這個事情安排的明明白白的。
Github地址
https://github.com/nficano/pytube
文檔地址
https://python-pytube.readthedocs.io
安裝方式
pip install pytube
快速上手
from pytube import YouTube
YouTube('http://youtube.com/watch?v=9bZkp7q19f0').streams.first().download()
- pytube的
first()方法，按照作者的解釋，會選取最高分辨率的視頻進行下載，但親測後發現效果並不理想。 - YouTube的是採用DASH Streams的技術架構，其中的DASH技術會將視頻、音頻進行獨立拆分，比如視頻有480p video，720p video，音頻有44100採樣 audio，22050採樣audio。通過以下代碼即可輸出DASH的Representation描述信息：
yt = YouTube('http://youtube.com/watch?v=9bZkp7q19f0')
yt.streams.all()
[<Stream: itag="22" mime_type="video/mp4" res="720p" fps="30fps" vcodec="avc1.64001F" acodec="mp4a.40.2">,
<Stream: itag="43" mime_type="video/webm" res="360p" fps="30fps" vcodec="vp8.0" acodec="vorbis">,
<Stream: itag="18" mime_type="video/mp4" res="360p" fps="30fps" vcodec="avc1.42001E" acodec="mp4a.40.2">,
<Stream: itag="36" mime_type="video/3gpp" res="240p" fps="30fps" vcodec="mp4v.20.3" acodec="mp4a.40.2">,
<Stream: itag="17" mime_type="video/3gpp" res="144p" fps="30fps" vcodec="mp4v.20.3" acodec="mp4a.40.2">,
<Stream: itag="137" mime_type="video/mp4" res="1080p" fps="30fps" vcodec="avc1.640028">,
<Stream: itag="248" mime_type="video/webm" res="1080p" fps="30fps" vcodec="vp9">,
<Stream: itag="136" mime_type="video/mp4" res="720p" fps="30fps" vcodec="avc1.4d401f">,
<Stream: itag="247" mime_type="video/webm" res="720p" fps="30fps" vcodec="vp9">,
<Stream: itag="135" mime_type="video/mp4" res="480p" fps="30fps" vcodec="avc1.4d401e">,
<Stream: itag="244" mime_type="video/webm" res="480p" fps="30fps" vcodec="vp9">,
<Stream: itag="134" mime_type="video/mp4" res="360p" fps="30fps" vcodec="avc1.4d401e">,
<Stream: itag="243" mime_type="video/webm" res="360p" fps="30fps" vcodec="vp9">,
<Stream: itag="133" mime_type="video/mp4" res="240p" fps="30fps" vcodec="avc1.4d4015">,
<Stream: itag="242" mime_type="video/webm" res="240p" fps="30fps" vcodec="vp9">,
<Stream: itag="160" mime_type="video/mp4" res="144p" fps="30fps" vcodec="avc1.4d400c">,
<Stream: itag="278" mime_type="video/webm" res="144p" fps="30fps" vcodec="vp9">,
<Stream: itag="140" mime_type="audio/mp4" abr="128kbps" acodec="mp4a.40.2">,
<Stream: itag="171" mime_type="audio/webm" abr="128kbps" acodec="vorbis">,
<Stream: itag="249" mime_type="audio/webm" abr="50kbps" acodec="opus">,
<Stream: itag="250" mime_type="audio/webm" abr="70kbps" acodec="opus">,
<Stream: itag="251" mime_type="audio/webm" abr="160kbps" acodec="opus">]
- 其中
itag="22"的視頻爲720p並帶有音頻（acodec="mp4a.40.2"）的視頻文件；而itag="136"同樣的720p的，卻是無聲版視頻文件。 - 回到之前的pytube的
first()方法，該方法會優先混合音頻的視頻源，再選擇無聲版視頻源。這就導致一種極端情況發生，first()會簡單粗暴的選擇了低分辨率的混合版視頻源，忽略了高清版視頻源。 - 我自己對視頻篩選邏輯進行重新改寫，後面會說明。
視頻篩選
- pytube提供了多種視頻篩選策略
1、傳統混合音頻的視頻源
- 設置參數爲
progressive=True
yt.streams.filter(progressive=True).all()
[<Stream: itag="22" mime_type="video/mp4" res="720p" fps="30fps" vcodec="avc1.64001F" acodec="mp4a.40.2">,
<Stream: itag="43" mime_type="video/webm" res="360p" fps="30fps" vcodec="vp8.0" acodec="vorbis">,
<Stream: itag="18" mime_type="video/mp4" res="360p" fps="30fps" vcodec="avc1.42001E" acodec="mp4a.40.2">,
<Stream: itag="36" mime_type="video/3gpp" res="240p" fps="30fps" vcodec="mp4v.20.3" acodec="mp4a.40.2">,
<Stream: itag="17" mime_type="video/3gpp" res="144p" fps="30fps" vcodec="mp4v.20.3" acodec="mp4a.40.2">]
2、DASH流的視頻源
- 設置參數爲
adaptive=True
yt.streams.filter(adaptive=True).all()
[<Stream: itag="137" mime_type="video/mp4" res="1080p" fps="30fps" vcodec="avc1.640028">,
<Stream: itag="248" mime_type="video/webm" res="1080p" fps="30fps" vcodec="vp9">,
<Stream: itag="136" mime_type="video/mp4" res="720p" fps="30fps" vcodec="avc1.4d401f">,
<Stream: itag="247" mime_type="video/webm" res="720p" fps="30fps" vcodec="vp9">,
<Stream: itag="135" mime_type="video/mp4" res="480p" fps="30fps" vcodec="avc1.4d401e">,
<Stream: itag="244" mime_type="video/webm" res="480p" fps="30fps" vcodec="vp9">,
<Stream: itag="134" mime_type="video/mp4" res="360p" fps="30fps" vcodec="avc1.4d401e">,
<Stream: itag="243" mime_type="video/webm" res="360p" fps="30fps" vcodec="vp9">,
<Stream: itag="133" mime_type="video/mp4" res="240p" fps="30fps" vcodec="avc1.4d4015">,
<Stream: itag="242" mime_type="video/webm" res="240p" fps="30fps" vcodec="vp9">,
<Stream: itag="160" mime_type="video/mp4" res="144p" fps="30fps" vcodec="avc1.4d400c">,
<Stream: itag="278" mime_type="video/webm" res="144p" fps="30fps" vcodec="vp9">,
<Stream: itag="140" mime_type="audio/mp4" abr="128kbps" acodec="mp4a.40.2">,
<Stream: itag="171" mime_type="audio/webm" abr="128kbps" acodec="vorbis">,
<Stream: itag="249" mime_type="audio/webm" abr="50kbps" acodec="opus">,
<Stream: itag="250" mime_type="audio/webm" abr="70kbps" acodec="opus">,
<Stream: itag="251" mime_type="audio/webm" abr="160kbps" acodec="opus">]
3、其它過濾條件
only_audio=True：只下載音頻only_video：只下載視頻subtype='mp4'：下載擴展名爲“mp4”的文件，包括音頻和視頻res="720p"：下載清晰度爲720p的視頻abr="64kbps"：下載碼率爲64kbps的視頻video_codec="vp9"：下載壓縮格式爲vp9的視頻audio_codec="vorbis"：下載壓縮格式爲vorbis的音頻
通過itag下載視頻
- YouTube對每個DASH流的視頻源的類型給了一個獨立的id，稱爲itag
- 可通過
get_by_itag方法下載對應視頻
yt.streams.get_by_itag(22)
- itag對應的類型如下
| itag Code | Container | Content | Resolution | Bitrate | Range | VR / 3D |
|---|---|---|---|---|---|---|
| 5 | flv | audio/video | 240p | - | - | - |
| 6 | flv | audio/video | 270p | - | - | - |
| 17 | 3gp | audio/video | 144p | - | - | - |
| 18 | mp4 | audio/video | 360p | - | - | - |
| 22 | mp4 | audio/video | 720p | - | - | - |
| 34 | flv | audio/video | 360p | - | - | - |
| 35 | flv | audio/video | 480p | - | - | - |
| 36 | 3gp | audio/video | 180p | - | - | - |
| 37 | mp4 | audio/video | 1080p | - | - | - |
| 38 | mp4 | audio/video | 3072p | - | - | - |
| 43 | webm | audio/video | 360p | - | - | - |
| 44 | webm | audio/video | 480p | - | - | - |
| 45 | webm | audio/video | 720p | - | - | - |
| 46 | webm | audio/video | 1080p | - | - | - |
| 82 | mp4 | audio/video | 360p | - | - | 3D |
| 83 | mp4 | audio/video | 480p | - | - | 3D |
| 84 | mp4 | audio/video | 720p | - | - | 3D |
| 85 | mp4 | audio/video | 1080p | - | - | 3D |
| 92 | hls | audio/video | 240p | - | - | 3D |
| 93 | hls | audio/video | 360p | - | - | 3D |
| 94 | hls | audio/video | 480p | - | - | 3D |
| 95 | hls | audio/video | 720p | - | - | 3D |
| 96 | hls | audio/video | 1080p | - | - | - |
| 100 | webm | audio/video | 360p | - | - | 3D |
| 101 | webm | audio/video | 480p | - | - | 3D |
| 102 | webm | audio/video | 720p | - | - | 3D |
| 132 | hls | audio/video | 240p | - | - | |
| 133 | mp4 | video | 240p | - | - | |
| 134 | mp4 | video | 360p | - | - | |
| 135 | mp4 | video | 480p | - | - | |
| 136 | mp4 | video | 720p | - | - | |
| 137 | mp4 | video | 1080p | - | - | |
| 138 | mp4 | video | 2160p60 | - | - | |
| 139 | m4a | audio | - | 48k | - | |
| 140 | m4a | audio | - | 128k | - | |
| 141 | m4a | audio | - | 256k | - | |
| 151 | hls | audio/video | 72p | - | - | |
| 160 | mp4 | video | 144p | - | - | |
| 167 | webm | video | 360p | - | - | |
| 168 | webm | video | 480p | - | - | |
| 169 | webm | video | 1080p | - | - | |
| 171 | webm | audio | - | 128k | - | |
| 218 | webm | video | 480p | - | - | |
| 219 | webm | video | 144p | - | - | |
| 242 | webm | video | 240p | - | - | |
| 243 | webm | video | 360p | - | - | |
| 244 | webm | video | 480p | - | - | |
| 245 | webm | video | 480p | - | - | |
| 246 | webm | video | 480p | - | - | |
| 247 | webm | video | 720p | - | - | |
| 248 | webm | video | 1080p | - | - | |
| 249 | webm | audio | - | 50k | - | |
| 250 | webm | audio | - | 70k | - | |
| 251 | webm | audio | - | 160k | - | |
| 264 | mp4 | video | 1440p | - | - | |
| 266 | mp4 | video | 2160p60 | - | - | |
| 271 | webm | video | 1440p | - | - | |
| 272 | webm | video | 4320p | - | - | |
| 278 | webm | video | 144p | - | - | |
| 298 | mp4 | video | 720p60 | - | - | |
| 299 | mp4 | video | 1080p60 | - | - | |
| 302 | webm | video | 720p60 | - | - | |
| 303 | webm | video | 1080p60 | - | - | |
| 308 | webm | video | 1440p60 | - | - | |
| 313 | webm | video | 2160p | - | - | |
| 315 | webm | video | 2160p60 | - | - | |
| 330 | webm | video | 144p60 | - | hdr | |
| 331 | webm | video | 240p60 | - | hdr | |
| 332 | webm | video | 360p60 | - | hdr | |
| 333 | webm | video | 480p60 | - | hdr | |
| 334 | webm | video | 720p60 | - | hdr | |
| 335 | webm | video | 1080p60 | - | hdr | |
| 336 | webm | video | 1440p60 | - | hdr | |
| 337 | webm | video | 2160p60 | - | hdr | |
| 394 | mp4 | video | 144p | - | - | |
| 395 | mp4 | video | 240p | - | - | |
| 396 | mp4 | video | 360p | - | - | |
| 397 | mp4 | video | 480p | - | - | |
| 398 | mp4 | video | 720p | - | - | |
| 399 | mp4 | video | 1080p | - | - | |
| 400 | mp4 | video | 1440p | - | - | |
| 401 | mp4 | video | 2160p | - | - | |
| 402 | mp4 | video | 2880p | - | - |
關於網絡
- 因爲需要避免西方資本主義思想毒害，網絡經常請求不穩定
- 常見的錯誤會有以下兩種：
HTTPErrorURLError- 使用Pycharm的同學還會遇到
ConnectionResetError
- 前兩種錯誤需要引入
from urllib.error import HTTPError, URLError - 然後通過where循環，try…except… 來重複請求
yt = None
while True:
try:
yt = YouTube(url)
break
except HTTPError:
self.logger.error("請求出錯一次：HTTPError")
continue
except URLError:
self.logger.error("請求出錯一次：URLError")
continue
streams = yt.streams.filter(subtype='mp4').all()
下載視頻
- 當確認了符合條件的視頻後，可通過
download的方式直接下載
from pytube import YouTube
yt=YouTube('http://youtube.com/watch?v=9bZkp7q19f0')
mp4=yt.streams.first()
mp4.download(output_path, filename, filename_prefix)
- 其中
download會接受3個參數：output_path：視頻輸出路徑；filename：視頻輸出名稱，默認爲視頻的標題，該名稱不需要擴展名；filename_prefix：視頻名稱前綴，這裏主要是區分音頻和視頻，因爲音頻和視頻下載後名稱相同，格式相同，前者會被後者覆蓋掉。可以增加前綴來進行區分，比如音頻爲“audio_FilmTitle.mp4”、視頻爲“video_FilmTitle.mp4”