Can't open an m4a file

[luni-4]

Hi FFmpeg developers!

I've tried to convert the m4a file attached to this issue in this way:

ffmpeg -i adts_m4a_aac_no_stream.m4a sample.mp3

ffmpeg version N-47548-g8a3ed5a313 Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 8 (Ubuntu 8.3.0-6ubuntu1~18.10)
  configuration: --disable-debug --disable-stripping --disable-libdrm --disable-cuda --enable-avisynth --enable-fontconfig --enable-gmp --enable-gnutls --enable-gpl --enable-ladspa --enable-libass --enable-libbluray --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libv4l2 --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libaom --enable-libxvid --enable-shared --enable-version3
  libavutil      56. 26.100 / 56. 26.100
  libavcodec     58. 51.100 / 58. 51.100
  libavformat    58. 27.102 / 58. 27.102
  libavdevice    58.  7.100 / 58.  7.100
  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
[aac @ 0x55830faeac00] Could not find codec parameters for stream 0 (Audio: aac, 0 channels, fltp): unspecified sample rate
Consider increasing the value for the 'analyzeduration' and 'probesize' options
Input #0, aac, from 'adts_m4a_aac_no_stream.m4a':
  Duration: N/A, bitrate: N/A
    Stream #0:0: Audio: aac, 0 channels, fltp
Output #0, mp3, to 'sample.mp3':
Output file #0 does not contain any stream

I've increased the value of analyzeduration and probesize, but nothing has changed.

The file can be opened and reproduced using VLC, so it isn't corrupted.

Thanks in advance for the reply!

[luni-4]

An m4a file with the ADTS format an AAC codec inside

[James]

Looks like a regression since e023334661e6eafcf638ffc2a780fd495fc25ec9

The file is not an m4a, it's a raw adts aac file, but libavformat figured that on its own just fine.

[luni-4]

Oh, great. Out of curiosity, why the phone has saved that as a m4a file format?

[Carl Eugen Hoyos]

I believe this is a duplicate of ticket #7271.