How to decrypt

[conner]

1.

mp4dash --widevine-header provider:widevine_test#content_id:2a --encryption-key aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb video-source.mp4

2.

[Attachment 49679 - Click to enlarge]

[Attachment 49680 - Click to enlarge]

[Attachment 49681 - Click to enlarge]


mp4decrypt --key 1:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa --key 2:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb init.mp4 out.mp4

It doesn't work

https://mega.nz/#!idpV3aDB!Er_zza8HedEJJ2I_-DZr8QPEPT6DoaRaFuClWShFkus

[Sviests]

First you have to merge those .m4s in to init.mp4 files with curl (video and audio separately),then merge video and audio with ffmpeg , then use the mp4decrypt.exe
If you have managed to actually write the decryption key to use as aaaa and bbbb - good for you,if not - no chance to decrypt.

[conner]

Thanks for the reply

How to merge video and audio with ffmpeg

cat init.mp4 > v.mp4
cat seg-1.m4s >> v.mp4
cat seg-2.m4s >> v.mp4
cat seg-3.m4s >> v.mp4

cat init.mp4 > a.mp4
cat seg-1.m4s >> a.mp4
cat seg-2.m4s >> a.mp4
cat seg-3.m4s >> a.mp4


ffmpeg -i a.mp4 -i v.mp4 -vcodec copy -acodec copy enc.mp4

ffmpeg version 3.2.14-1~deb9u1 Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 6.3.0 (Debian 6.3.0-18+deb9u1) 20170516
  configuration: --prefix=/usr --extra-version='1~deb9u1' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libebur128 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
  libavutil      55. 34.101 / 55. 34.101
  libavcodec     57. 64.101 / 57. 64.101
  libavformat    57. 56.101 / 57. 56.101
  libavdevice    57.  1.100 / 57.  1.100
  libavfilter     6. 65.100 /  6. 65.100
  libavresample   3.  1.  0 /  3.  1.  0
  libswscale      4.  2.100 /  4.  2.100
  libswresample   2.  3.100 /  2.  3.100
  libpostproc    54.  1.100 / 54.  1.100
[aac @ 0x5569b1ccc640] Number of bands (58) exceeds limit (37).
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'a.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41iso5iso6
  Duration: 00:00:05.03, start: 0.000000, bitrate: 53 kb/s
    Stream #0:0(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 48 kb/s (default)
    Metadata:
      handler_name    : Bento4 Sound Handler
[h264 @ 0x5569b1ce95e0] top block unavailable for requested intra mode -1
[h264 @ 0x5569b1ce95e0] error while decoding MB 31 0, bytestream 33068
[h264 @ 0x5569b1ce95e0] concealing 3060 DC, 3060 AC, 3060 MV errors in I frame
Input #1, mov,mp4,m4a,3gp,3g2,mj2, from 'v.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41iso5iso6
  Duration: 00:00:05.07, start: 0.000000, bitrate: 394 kb/s
    Stream #1:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p, 1086x720 [SAR 1:1 DAR 181:120], 383 kb/s, SAR 10680:10679 DAR 89:59, 30 fps, 30 tbr, 15360 tbn, 60 tbc (default)
    Metadata:
      handler_name    : Bento4 Video Handler
[mp4 @ 0x5569b1cfefc0] track 1: codec frame size is not set
Output #0, mp4, to 'enc.mp4':
Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41iso5iso6
    encoder         : Lavf57.56.101
    Stream #0:0(und): Video: h264 (Main) ([33][0][0][0] / 0x0021), yuv420p, 1086x720 [SAR 10680:10679 DAR 89:59], q
=2-31, 383 kb/s, 30 fps, 30 tbr, 15360 tbn, 15360 tbc (default)
    Metadata:
      handler_name    : Bento4 Video Handler
    Stream #0:1(und): Audio: aac (LC) ([64][0][0][0] / 0x0040), 48000 Hz, stereo, 48 kb/s (default)
    Metadata:
      handler_name    : Bento4 Sound Handler
Stream mapping:
  Stream #1:0 -> #0:0 (copy)
  Stream #0:0 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame=  152 fps=0.0 q=-1.0 Lsize=     272kB time=00:00:04.99 bitrate= 445.8kbits/s speed=1.31e+03x    
video:237kB audio:30kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.768678%