使用 ffmpeg 解密碎片化的 mpeg-dash

Question

我有一个要解密的 mpeg-dash。 我有 CENC 解密密钥。 但我无法让它工作。 破折号使用段模板。 这是破折号

<?xml version="1.0" ?>
<MPD mediaPresentationDuration="PT1H55M53.987S" minBufferTime="PT6.00S" profiles="urn:mpeg:dash:profile:isoff-live:2011" type="static" xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:cenc="urn:mpeg:cenc:2013" xmlns:mspr="urn:microsoft:playready">
  <!-- Created with Bento4 mp4-dash.py, VERSION=1.8.0-629 -->
  <Period>
    <!-- Video -->
    <AdaptationSet maxHeight="720" maxWidth="1280" mimeType="video/mp4" segmentAlignment="true" startWithSAP="1">
      <Accessibility schemeIdUri="urn:scte:dash:cc:cea-608:2015" value="eng"/>
      <Viewpoint schemeIdUri="urn:mpeg:dash:role:2011" value="vp2"/>
      <!-- MPEG Common Encryption -->
      <ContentProtection cenc:default_KID="3cb715f2-4eac-cb21-a459-5c4a671dbb0a" schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc"/>
      <!-- PlayReady -->
      <ContentProtection schemeIdUri="urn:uuid:9a04f079-9840-4286-ab92-e65be0885f95">
        <mspr:pro>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</mspr:pro>
      </ContentProtection>
      <!-- Widevine -->
      <ContentProtection schemeIdUri="urn:uuid:edef8ba9-79d6-4ace-a3c8-27dcd51d21ed">
        <cenc:pssh>AAAAQ3Bzc2gAAAAA7e+LqXnWSs6jyCfc1R0h7QAAACMIARIQPLcV8k6syyGkWVxKZx27ChoKaW50ZXJ0cnVzdCIBKg==</cenc:pssh>
      </ContentProtection>
      <SegmentTemplate duration="6000" initialization="$RepresentationID$/init.mp4" media="$RepresentationID$/seg-$Number$.m4s" startNumber="1" timescale="1000"/>
      <Representation bandwidth="634478" codecs="avc1.4D401F" frameRate="2997/100" height="288" id="video/avc1/1" scanType="progressive" width="512"/>
      <Representation bandwidth="789637" codecs="avc1.4D401F" frameRate="2997/100" height="360" id="video/avc1/2" scanType="progressive" width="640"/>
      <Representation bandwidth="1562569" codecs="avc1.4D401F" frameRate="2997/100" height="432" id="video/avc1/3" scanType="progressive" width="768"/>
      <Representation bandwidth="2124583" codecs="avc1.4D401F" frameRate="2997/100" height="720" id="video/avc1/4" scanType="progressive" width="1280"/>
    </AdaptationSet>
    <!-- Audio -->
    <AdaptationSet lang="en" mimeType="audio/mp4" segmentAlignment="true" startWithSAP="1">
      <!-- MPEG Common Encryption -->
      <ContentProtection cenc:default_KID="3cb715f2-4eac-cb21-a459-5c4a671dbb0a" schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc"/>
      <!-- PlayReady -->
      <ContentProtection schemeIdUri="urn:uuid:9a04f079-9840-4286-ab92-e65be0885f95">
        <mspr:pro>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</mspr:pro>
      </ContentProtection>
      <!-- Widevine -->
      <ContentProtection schemeIdUri="urn:uuid:edef8ba9-79d6-4ace-a3c8-27dcd51d21ed">
        <cenc:pssh>AAAAQ3Bzc2gAAAAA7e+LqXnWSs6jyCfc1R0h7QAAACMIARIQPLcV8k6syyGkWVxKZx27ChoKaW50ZXJ0cnVzdCIBKg==</cenc:pssh>
      </ContentProtection>
      <SegmentTemplate duration="6000" initialization="$RepresentationID$/init.mp4" media="$RepresentationID$/seg-$Number$.m4s" startNumber="1" timescale="1000"/>
      <Representation audioSamplingRate="48000" bandwidth="136225" codecs="mp4a.40.2" id="audio/en/mp4a">
        <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
      </Representation>
    </AdaptationSet>
  </Period>
</MPD>

我通过组合这样的所有片段生成了一个 mp4 文件

init.mp4+seg-1.m4s+seg-2.m4s+....+seg-1159.m4s

但我最终出现以下错误

ffmpeg version N-99631-g9018257751-anan5a-2020-10-19 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 8 (Debian 8.3.0-6)
  configuration: --extra-version=anan5a-2020-10-19 --enable-gpl --enable-version3 --disable-shared --enable-static --enable-small --enable-avisynth --enable-chromaprint --enable-frei0r --enable-gmp --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-librtmp --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtesseract --enable-libtheora --enable-libtwolame --enable-libv4l2 --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libxml2 --enable-libzmq --enable-libzvbi --enable-lv2 --enable-openal --enable-opencl --enable-opengl --enable-libdrm --enable-nonfree --enable-libfdk-aac --enable-libbluray --enable-libzimg --enable-libsvtav1
  libavutil      56. 60.100 / 56. 60.100
  libavcodec     58.111.101 / 58.111.101
  libavformat    58. 62.100 / 58. 62.100
  libavdevice    58. 11.102 / 58. 11.102
  libavfilter     7. 87.100 /  7. 87.100
  libswscale      5.  8.100 /  5.  8.100
  libswresample   3.  8.100 /  3.  8.100
  libpostproc    55.  8.100 / 55.  8.100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x557789b49300] Incorrect number of samples in encryption info
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x557789b49300] Could not find codec parameters for stream 0 (Video: h264 (avc1 / 0x31637661), none, 512x288, 616 kb/s): unspecified pixel format
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '../videos/enc.0a7bd4e9ec72b6e0-5549.mkv':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41iso5iso6
  Duration: 01:55:47.95, bitrate: 625 kb/s
    Stream #0:0(eng): Video: h264 (avc1 / 0x31637661), none, 512x288, 616 kb/s, SAR 1:1 DAR 16:9, 29.97 fps, 11988 tbr, 11988 tbn, 23976 tbc (default)
    Metadata:
      handler_name    : Bento4 Video Handler
    Side data:
      unknown side data type 24 (779 bytes)
Output #0, matroska, to '../videos/dec.0a7bd4e9ec72b6e0-5549.mkv':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41iso5iso6
    encoder         : Lavf58.62.100
    Stream #0:0(eng): Video: h264 (avc1 / 0x31637661), none, 512x288 [SAR 1:1 DAR 16:9], q=2-31, 616 kb/s, 29.97 fps, 11988 tbr, 1k tbn, 11988 tbc (default)
    Metadata:
      handler_name    : Bento4 Video Handler
    Side data:
      unknown side data type 24 (779 bytes)
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
Press [q] to stop, [?] for help
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x557789b49300] Incorrect number of samples in encryption info
../videos/enc.0a7bd4e9ec72b6e0-5549.mkv: Invalid data found when processing input
frame=    0 fps=0.0 q=-1.0 Lsize=       1kB time=00:00:00.00 bitrate=N/A speed=   0x    
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown

我怎样才能实现无错误的解密？

Answer 1

经过一些试验和错误，我能够解决这个问题。 这并不像加入文件那么简单。 所以这是我的解决方案init.mp4必须用于每个单独的段以实现解密。 所以这是解决方案

init.mp4+seg-1.m4s <-- now this can be decrypted
init.mp4+seg-2.m4s <-- this can be as well!

最后使用 ffmpeg 复制映射合并它们。