[FFmpeg-user] DTS-HD MA decoding error

[Felix Muster]

I did this:

ffmpeg -i input.mkv -map 0:1 -c copy -f rawvideo out1.dts
clean log

mkvextract tracks input.mkv 1:out2.dts
also no errors or warnings

out1.dts and out2.dts are bit-identical.

Then I tried to convert the raw dts-stream:

ffmpeg -i out1.dts -c:a alac alac.m4a
ffmpeg version N-93069-g6dc06e979c Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 8.2.1 (GCC) 20181201
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt
  libavutil      56. 26.100 / 56. 26.100
  libavcodec     58. 46.100 / 58. 46.100
  libavformat    58. 26.100 / 58. 26.100
  libavdevice    58.  6.101 / 58.  6.101
  libavfilter     7. 48.100 /  7. 48.100
  libswscale      5.  4.100 /  5.  4.100
  libswresample   3.  4.100 /  3.  4.100
  libpostproc    55.  4.100 / 55.  4.100
Input #0, dts, from 'out1.dts':
  Duration: N/A, start: 0.000000, bitrate: N/A
    Stream #0:0: Audio: dts (DTS-HD MA), 48000 Hz, 5.1(side), s16p
Stream mapping:
  Stream #0:0 -> #0:0 (dts (dca) -> alac (native))
Press [q] to stop, [?] for help
Output #0, ipod, to 'alac.m4a':
  Metadata:
    encoder         : Lavf58.26.100
    Stream #0:0: Audio: alac (alac / 0x63616C61), 48000 Hz, 5.1, s16p, 128 kb/s
    Metadata:
      encoder         : Lavc58.46.100 alac
size=    1792kB time=00:00:22.44 bitrate= 654.1kbits/s speed=43.6x    
[...]    
size=  791296kB time=01:27:05.89 bitrate=1240.4kbits/s speed=37.8x    
[dca @ 00000000003b96c0] Failed to decode block code(s)
Error while decoding stream #0:0: Invalid data found when processing input
size=  793600kB time=01:27:29.03 bitrate=1238.5kbits/s speed=37.8x    
[...]
size= 1592971kB time=02:54:56.43 bitrate=1243.2kbits/s speed=37.5x    
video:0kB audio:1592466kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.031661%


Same error at same timestamp.
Second error message "Residual encoded channels are present without core" is gone but the other error message persists.