ffprobe is unable to parse certain mp3 files

[vlad312]

• What I was trying to accomplish:

I'm trying to accurately determine the bitrate and duration of the MP3 file by using ffprobe
to output information about each audio packet (namely, pts_time, duration_time and size),
and then using this information to determine file's duration and bitrate.

Namely, file's duration is determined as pts_time+duration_time from the last packet,
and file's bitrate is determined as 8*(sum of sizes of all packets)/file's duration.

• The problem I encountered:

ffprobe was unable to parse all packets of the MP3 file, resulting in the wrong value of the duration and bitrate.

• The exact command line I was using

The command line I'm using looks like this:

ffprobe -v error -select_streams a:0 -show_entries packet=pts_time,duration_time,size -of compact ffprobe_packet_parsing_bug.mp3

It outputs only 53 packets. Total size of the packets is 107760 bytes, the last packet looks like:
packet|pts_time=0.277333|duration_time=0.003291|size=1264

so the duration is 0.277333 + 0.003291 = 0.280624
and the bitrate is 8 * 107760 / 0.280624 = 3072011

When I'm using another approach like this:

ffprobe -v error -select_streams a:0 -show_entries stream=duration,bit_rate -of default=noprint_wrappers=1 ffprobe_packet_parsing_bug.mp3

I'm also getting the wrong values:
duration=0.180625
bit_rate=3072000

The reported duration is wrong, as the file can be played e.g. in vlc and I'm getting the duration of about 536 seconds (08:56).
The reported bit_rate is also wrong, because the MP3 cannot have a bitrate greater than 320000.

I've processed a large amount of MP3 files and this approach generally
works very well. However, I've encountered a few files for which I'm
clearly getting the wrong result about the duration and bitrate, which
looks like a bug in ffprobe. It seems that ffmpeg is also unable to
properly parse this file.

• The full, uncut console output provided by ffmpeg -v 9 -loglevel 99 -i ffprobe_packet_parsing_bug.mp3

ffmpeg version 4.4.1 Copyright (c) 2000-2021 the FFmpeg developers

built with gcc 11 (Debian 11.2.0-12)
configuration: --disable-decoder=amrnb --disable-decoder=libopenjpeg --disable-gnutls --disable-liblensfun --disable-libopencv --disable-podpages --disable-sndio --disable-stripping --enable-avfilter --enable-gcrypt --enable-gpl --enable-ladspa --enable-libaom --enable-libaribb24 --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libdavs2 --enable-libdc1394 --enable-libfdk-aac --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libiec61883 --enable-libjack --enable-libkvazaar --enable-libmp3lame --enable-libmysofa --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librist --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libtesseract --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libwebp --enable-libx265 --enable-libxavs2 --enable-libxml2 --enable-libxvid --enable-libzimg --enable-libzmq --enable-libzvbi --enable-lv2 --enable-nonfree --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-openssl --enable-postproc --enable-pthreads --enable-shared --enable-version3 --enable-vulkan --incdir=/usr/include/x86_64-linux-gnu --libdir=/usr/lib/x86_64-linux-gnu --prefix=/usr --toolchain=hardened --enable-frei0r --enable-chromaprint --enable-libx264 --enable-vaapi --enable-libmfx --enable-libvmaf --enable-libsvtav1 --enable-libilbc --disable-altivec --shlibdir=/usr/lib/x86_64-linux-gnu
libavutil 56. 70.100 / 56. 70.100
libavcodec 58.134.100 / 58.134.100
libavformat 58. 76.100 / 58. 76.100
libavdevice 58. 13.100 / 58. 13.100
libavfilter 7.110.100 / 7.110.100
libswscale 5. 9.100 / 5. 9.100
libswresample 3. 9.100 / 3. 9.100
libpostproc 55. 9.100 / 55. 9.100

Splitting the commandline.
Reading option '-v' ... matched as option 'v' (set logging level) with argument '9'.
Reading option '-loglevel' ... matched as option 'loglevel' (set logging level) with argument '99'.
Reading option '-i' ... matched as input url with argument '/tmp/ffprobe_packet_parsing_bug.mp3'.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option v (set logging level) with argument 9.
Successfully parsed a group of options.
Parsing a group of options: input url /tmp/ffprobe_packet_parsing_bug.mp3.
Successfully parsed a group of options.
Opening an input file: /tmp/ffprobe_packet_parsing_bug.mp3.
[NULL @ 0x55e53e7ba800] Opening '/tmp/ffprobe_packet_parsing_bug.mp3' for reading
[file @ 0x55e53e7bb4c0] Setting default whitelist 'file,crypto,data'
Probing mp3 score:1 size:647
Probing mp3 score:1 size:2695
Probing libopenmpt score:76 size:2695
[libopenmpt @ 0x55e53e7ba800] Format libopenmpt probed with size=4096 and score=76
id3v2 ver:3 flags:00 len:1391
[libopenmpt @ 0x55e53e7ba800] Discarding ID3 tags because more suitable tags were found.
[libopenmpt @ 0x55e53e7ba800] Before avformat_find_stream_info() pos: 21425453 bytes read:21425453 seeks:0 nb_streams:1
[libopenmpt @ 0x55e53e7ba800] All info found
[libopenmpt @ 0x55e53e7ba800] stream 0: start_time: NOPTS duration: 0.180625
[libopenmpt @ 0x55e53e7ba800] format: start_time: NOPTS duration: 0.180625 (estimate from stream) bitrate=948947 kb/s
[libopenmpt @ 0x55e53e7ba800] After avformat_find_stream_info() pos: 21425453 bytes read:21425453 seeks:0 frames:50
Guessed Channel Layout for Input Stream #0.0 : stereo
Input #0, libopenmpt, from '/tmp/ffprobe_packet_parsing_bug.mp3':

Metadata:

title : ÿûàd ?ð i
encoder : Generic MOD-compatible Tracker
comment : ¤ 4€ LAME3.

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Duration: 00:00:00.18, bitrate: 948947 kb/s
Stream #0:0, 50, 1/1000000: Audio: pcm_f32le, 48000 Hz, stereo, flt, 3072 kb/s

Successfully opened the file.
At least one output file must be specified
[AVIOContext @ 0x55e53e7c3840] Statistics: 21425453 bytes read, 0 seeks

• Sufficient information, including any required input files, to reproduce the bug and confirm a potential fix.

I've uploaded the file "ffprobe_packet_parsing_bug.mp3" to ​the VideoLAN File Uploader (file size is 21425453 bytes, md5 is 452c0dabf3398fc64fb2588ce3a513d3).