如何下载知乎 m3u8 视频

[mingyun]

视频地址 https://v.vzuu.com/video/930514486520012800 抓包看到 https://lens.zhihu.com/api/videos/930514486520012800 这个请求 ，里面有 m3u8 地址，但是用 ffmpeg 下载失败了

$ ffmpeg  -i 'https://vdn.vzuu.com/Act-ss-m3u8-hd/74d0edb67b0c44dca559375da1e4df74/6005a040-ed51-11e7-9313-0242ac112a03None.m3u8?auth_key=1515338325-0-0-89d1ba089ceda0022fff9f4448af9786&expiration=1515338325&disable_local_cache=0' 'jump.mp4'
[https @ 0000000000099280] HTTP error 403 Forbidden
https://vdn.vzuu.com/Act-ss-m3u8-hd/74d0edb67b0c44dca559375da1e4df74/6005a040-ed51-11e7-9313-0242ac112a03None.m3u8?auth_key=1515338325-0-0-89d1ba089ceda0022fff9f4448af9786&expiration=1515338325&disable_local_cache=0: Server returned 403 For
bidden (access denied)

[mingyun]

播放视频的时候会请求 https://lens.zhihu.com/api/videos/989827766300401664 返回值里有 m3u8 地址 https://vdn.vzuu.com/Act-ss-m3u8-hd/5f9fea8c25764f18aa33d12c5563feff/dc085598-6dee-11e8-824c-0242ac112a0f.m3u8?auth_key=1535385091-0-0-da5c677c79754acee6456df95f8abbd2&expiration=1535385091&disable_local_cache=0

[mingyun]

ffmpeg -i "https://xxx.m3u8" -vcodec copy -acodec copy -absf aac_adtstoasc baihespxyz.mp4