创建使用Clear Key加密加密的可播放DASH视频

Question

我正在尝试对Google Shaka播放器进行转码和DASH(使用Clear Key加密)示例H.264文件.我已经能够在线拼凑的每一组步骤都会在未加密的情况下生成可播放的版本,然后在我尝试加密时进行分解.

未加密

以下是我处理未加密版本的步骤:

1. 将视频与音频分开

   ffmpeg -i input.mp4 -an -c copy video_only.mp4
   ffmpeg -i input.mp4 -map 0:2 -c copy audio_only.m4a
   

2. 将视频转码为工作变体(目前只有1个)

   ffmpeg -i video_only.mp4 -an -vcodec libx264 -s 1280x720 -c:v libx264 -b:v 384k -bf 2 -g 90 -sc_threshold 0 -an -strict experimental video_only_384kbps.mp4
   

3A.创建mpd

    MP4Box -dash 5000 -segment-name 'outputseg-%s' -url-template -bs-switching no \
        -out output.mpd -rap \
        audio_only.m4a \
        video_only_384kbps.mp4

4A.将视频加载到Osmo4或Google Shaka中播放.

使用加密

现在,我尝试分层加密.从上面的第2步开始:

3B.使用Clear Key加密变体

    MP4Box -crypt drm.xml audio_only.m4a -out audio_only_encrypted.m4a
    MP4Box -crypt drm.xml video_only_384kbps.mp4 -out video_only_384kbps_encrypted.mp4

其中drm.xml包含直接从MP4Box/GPAC站点派生的样本:

    <?xml version="1.0" encoding="UTF-8"?>
    <GPACDRM type="CENC AES-CTR">
      <!-- example for GPAC - keys are listed after the content and UL follows -->
      <DRMInfo cypherIV="0x00000000000000000000000000000001" cypherKey="0x6770616363656E6364726D746F6F6C31" cypherOffset="9" type="pssh" version="1">
        <BS ID128="6770616363656E6364726D746F6F6C31"/>
        <BS bits="32" value="2"/>
        <BS ID128="0x279926496a7f5d25da69f2b3b2799a7f"/>
        <BS ID128="0x676cb88f302d10227992649885984045"/>
        <BS bits="8" string="CID=Toto"/>
        <BS ID128="0xccc0f2b3b279926496a7f5d25da692f6"/>
        <BS ID128="0xccc0f2b3b279926496a7f5d25da692d6"/>
      </DRMInfo>
      <CrypTrack IV_size="16" IsEncrypted="1" first_IV="0x0a610676cb88f302d10ac8bc66e039ed" saiSavedBox="senc" trackID="1">
        <key KID="0x279926496a7f5d25da69f2b3b2799a7f" value="0xccc0f2b3b279926496a7f5d25da692f6"/>
      </CrypTrack>
    </GPACDRM>

4B.创建mpd

MP4Box -dash 5000 -segment-name 'outputseg-%s' -url-template -bs-switching no \
    -out output.mpd -rap \
    audio_only_encrypted.m4a \
    video_only_384kbps_encrypted.mp4

5B.将视频加载到Osmo4或Google Shaka中.*在Osmo4上,没有发现任何错误,但玩家只是挂起,直到我杀了它*在Google Shaka上,我一直收到一个玩家错误:"CustomEvent {detail:错误:没有DrmInfo存在!在shaka.media.EmeManager.buildKeySystemQueries_(http :// localhost:808 ...,srcElement:null,target:s ... ap ... r.Player,currentTarget:s ... ap ... r.Player}

5b之后的output.mpd如下所示:

    <?xml version="1.0"?>
    <!-- MPD file Generated with GPAC version 0.5.2-DEV-rev566-g4c06d0f-master  at 2015-09-03T19:17:57.544Z-->
    <MPD xmlns="urn:mpeg:dash:schema:mpd:2011" minBufferTime="PT1.500S" type="static" mediaPresentationDuration="PT0H0M54.424S" maxSegmentDuration="PT0H0M4.992S" profiles="urn:mpeg:dash:profile:full:2011" xmlns:cenc="urn:mpeg:cenc:2013">
     <ProgramInformation moreInformationURL="http://gpac.sourceforge.net">
      <Title>output.mpd generated by GPAC</Title>
     </ProgramInformation>

     <Period duration="PT0H0M54.424S">
      <AdaptationSet segmentAlignment="true" lang="eng">
       <Representation id="1" mimeType="audio/mp4" codecs="mp4a.40.2" audioSamplingRate="48000" startWithSAP="1" bandwidth="140631">
        <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
        <ContentProtection schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc" cenc:default_KID="27992649-6a7f-5d25-da69-f2b3b2799a7f"/>
        <SegmentTemplate timescale="48000" media="outputseg-audio_only_encrypted$Number$.m4s" startNumber="1" duration="239616" initialization="outputseg-audio_only_encryptedinit.mp4"/>
       </Representation>
      </AdaptationSet>
      <AdaptationSet segmentAlignment="true" maxWidth="1280" maxHeight="720" maxFrameRate="24" par="16:9" lang="eng">
       <Representation id="2" mimeType="video/mp4" codecs="avc1.64001f" width="1280" height="720" frameRate="24" sar="1:1" startWithSAP="1" bandwidth="375052">
        <ContentProtection schemeIdUri="urn:mpeg:dash:mp4protection:2011" value="cenc" cenc:default_KID="27992649-6a7f-5d25-da69-f2b3b2799a7f"/>
        <SegmentTemplate timescale="12288" media="outputseg-video_only_384kbps_encrypted$Number$.m4s" startNumber="1" duration="46080" initialization="outputseg-video_only_384kbps_encryptedinit.mp4"/>
       </Representation>
      </AdaptationSet>
     </Period>
    </MPD>

软件版本:

• MP4Box:GPAC版本0.5.2-DEV-rev566-g4c06d0f-master
• FFMPEG:ffmpeg版本2.6.3版权所有(c)2000-2015 FFmpeg开发人员使用Apple LLVM版本6.1.0(clang-602.0.53)构建(基于LLVM 3.6.0svn)

有没有人对如何进行有任何建议？