ios - hls aes 加密视频在 ios 上的 EXT-X-DISCONTINUITY 标签后无法播放

Question

看起来 ios 不喜欢将加密的 .ts 文件与 EXT-X-DISCONTINUITY 标记混合在一起的 hls m3u8 文件。

这是一个测试播放列表，它是两个视频的混合。预卷广告未加密，主视频已加密。两者单独播放都很好，但是当我将它们放在一个 m3u8 中(由 EXT-X-DISCONTINUITY 分隔)时，仅播放预卷，然后播放器停止。

#EXTM3U
#EXT-X-TARGETDURATION:10
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/vig_400-0.ts
#EXTINF:10,
http://ixemes-ppweb.ixemes.com/prerollmain/vig_400-1.ts
#EXT-X-DISCONTINUITY
#EXTINF:10,
#EXT-X-KEY:METHOD=AES-128,URI="http://ixemes-ppweb.ixemes.com/prerollmain/113760.key"
http://ixemes-ppweb.ixemes.com/prerollmain/02-0.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-1.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-2.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-3.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-4.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-5.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-6.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-7.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-8.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-9.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-10.ts
#EXTINF:10,     
http://ixemes-ppweb.ixemes.com/prerollmain/02-11.ts
#EXTINF:2,      
http://ixemes-ppweb.ixemes.com/prerollmain/02-12.ts
#EXT-X-ENDLIST

我尝试过两个未加密的视频，效果很好。我在 HLS 规范中没有看到任何内容表明禁止对加密视频使用 EXT-X-DISCONTINUITY 标签:https://datatracker.ietf.org/doc/html/draft-pantos-http-live-streaming-08#section-6.3.3

所以我猜苹果对其自己的规范的实现是错误的，但也许是我做错了。

我制作了一个快速的 html 页面来测试它(在任何 ios5 设备上的 safari 中打开它):http://ixemes-ppweb.ixemes.com/prerollmain/index.html

Answer 1

我注意到你的 EXT-X-KEY 没有 IV 项，也称为初始化向量。标准支持这一点，例如:

#EXT-X-KEY:METHOD=AES-128,URI="https://priv.example.com/key.php?r=52",IV=0x9c7db8778570d05c3177c349fd9236aa

如果缺少此内容，请按以下方法 https://developer.apple.com/library/ios/technotes/tn2288/_index.html说玩家应该选择 IV:

The default Initialization Vector for media encryption (if none is specified) is the sequence number of the media file. You should specify an Initialization Vector value, and not rely on sequence numbers. The main reason for this is portability. For example, if you change where the segment appears in the playlist (e.g. inserting an ad), that changes its sequence number, requiring a re-encrypt.

在我的团队中，我们无法弄清楚为什么带有插入广告的加密内容无法播放。我们有一个播放加密内容的示例:

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-MEDIA-SEQUENCE:1
#EXT-X-ALLOW-CACHE:NO
#EXT-X-TARGETDURATION:11
#EXT-X-KEY:METHOD=AES-128,URI="http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans.key"
#EXTINF:11,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-1.ts
#EXTINF:7,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-2.ts
#EXTINF:7,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-3.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-4.ts
#EXTINF:10,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-5.ts
#EXTINF:6,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-6.ts
#EXTINF:9,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-7.ts
#EXTINF:7,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-8.ts
#EXTINF:9,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-9.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-10.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-11.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-12.ts
#EXTINF:6,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-13.ts
#EXTINF:9,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-14.ts
#EXTINF:5,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-15.ts
#EXT-X-ENDLIST

您可以尝试这个:http://demo.theplatform.com/dev/m3u8/encrypted.m3u8 。但是当我们在它之前插入内容时，就像这样，它没有播放:

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-MEDIA-SEQUENCE:1
#EXT-X-ALLOW-CACHE:NO
#EXT-X-TARGETDURATION:11
#EXT-X-KEY:METHOD=NONE
#EXTINF:10.01,
http://ne.edgecastcdn.net/0008B0/mps/Inkola_VMS/20/687/15_WordIsOut_UPFW1764H_1080p_20802040_m3u8_video_480x0_400000_primary_audio_eng_2_x5e1c9dd7b9834f38a319d348e1a5f9ee_00001.ts
#EXTINF:5.088,
http://ne.edgecastcdn.net/0008B0/mps/Inkola_VMS/20/687/15_WordIsOut_UPFW1764H_1080p_20802040_m3u8_video_480x0_400000_primary_audio_eng_2_x5e1c9dd7b9834f38a319d348e1a5f9ee_00002.ts
#EXT-X-DISCONTINUITY
#EXT-X-KEY:METHOD=AES-128,URI="http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans.key"
#EXTINF:11,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-1.ts
#EXTINF:7,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-2.ts
#EXTINF:7,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-3.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-4.ts
#EXTINF:10,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-5.ts
#EXTINF:6,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-6.ts
#EXTINF:9,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-7.ts
#EXTINF:7,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-8.ts
#EXTINF:9,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-9.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-10.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-11.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-12.ts
#EXTINF:6,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-13.ts
#EXTINF:9,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-14.ts
#EXTINF:5,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-15.ts
#EXT-X-ENDLIST

此网址为http://demo.theplatform.com/dev/m3u8/mix.m3u8 。我们发现问题是因为我们添加了两个片段，媒体序列号现在减少了 2。如果您明确地将 IV 设置为“0x00000000000000000000000000000001”，如下所示:

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-MEDIA-SEQUENCE:1
#EXT-X-ALLOW-CACHE:NO
#EXT-X-TARGETDURATION:11
#EXT-X-KEY:METHOD=NONE
#EXTINF:10.01,
http://ne.edgecastcdn.net/0008B0/mps/Inkola_VMS/20/687/15_WordIsOut_UPFW1764H_1080p_20802040_m3u8_video_480x0_400000_primary_audio_eng_2_x5e1c9dd7b9834f38a319d348e1a5f9ee_00001.ts
#EXTINF:5.088,
http://ne.edgecastcdn.net/0008B0/mps/Inkola_VMS/20/687/15_WordIsOut_UPFW1764H_1080p_20802040_m3u8_video_480x0_400000_primary_audio_eng_2_x5e1c9dd7b9834f38a319d348e1a5f9ee_00002.ts
#EXT-X-DISCONTINUITY
#EXT-X-KEY:METHOD=AES-128,URI="http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans.key",IV=0x00000000000000000000000000000001
#EXTINF:11,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-1.ts
#EXTINF:7,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-2.ts
#EXTINF:7,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-3.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-4.ts
#EXTINF:10,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-5.ts
#EXTINF:6,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-6.ts
#EXTINF:9,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-7.ts
#EXTINF:7,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-8.ts
#EXTINF:9,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-9.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-10.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-11.ts
#EXTINF:8,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-12.ts
#EXTINF:6,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-13.ts
#EXTINF:9,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-14.ts
#EXTINF:5,
http://playertest.longtailvideo.com/adaptive/oceans_aes/oceans_aes-audio=65000-video=2042000-15.ts
#EXT-X-ENDLIST

然后就可以了。您可以尝试使用 http://demo.theplatform.com/dev/m3u8/mix_fixed.m3u8 。所以也许这就是您遇到的问题。