[FFmpeg-trac] #810(avformat:new): Muxing MXF audio only files leads to a floating point exception

[FFmpeg]

#810: Muxing MXF audio only files leads to a floating point exception
--------------------------------------+----------------------------------
               Reporter:  ubitux      |                  Owner:
                   Type:  defect      |                 Status:  new
               Priority:  normal      |              Component:  avformat
                Version:  git-master  |               Keywords:  mxf
             Blocked By:              |               Blocking:
Reproduced by developer:  0           |  Analyzed by developer:  0
--------------------------------------+----------------------------------
 Steps to reproduce:

 {{{
 % make tests/audiogen
 % ./tests/audiogen a.sw 48000 2
 % ./ffmpeg -ar 48000 -ac 2 -i a.sw -y a.mxf
 }}}

 Backtrace:

 {{{
 (gdb) r
 Starting program: /home/ubitux/proj/ffmpeg/ffmpeg_g -ar 48000 -ac 2 -i
 a.sw -y a.mxf
 [Thread debugging using libthread_db enabled]
 ffmpeg version N-36003-gf27930c, Copyright (c) 2000-2011 the FFmpeg
 developers
   built on Dec 21 2011 00:07:07 with gcc 4.6.2 20111125 (prerelease)
   configuration: --enable-gpl --enable-libmp3lame --enable-libvorbis
 --enable-libxvid --enable-libx264 --enable-libvpx --enable-libtheora
 --enable-x11grab --enable-libopenjpeg --enable-version3 --enable-
 libmodplug --enable-libass --cc='ccache cc'
   libavutil    51. 32. 0 / 51. 32. 0
   libavcodec   53. 46. 1 / 53. 46. 1
   libavformat  53. 27. 0 / 53. 27. 0
   libavdevice  53.  4. 0 / 53.  4. 0
   libavfilter   2. 53. 0 /  2. 53. 0
   libswscale    2.  1. 0 /  2.  1. 0
   libpostproc  51.  2. 0 / 51.  2. 0
 [s16le @ 0x141d840] Estimating duration from bitrate, this may be
 inaccurate
 Input #0, s16le, from 'a.sw':
   Duration: N/A, start: 0.000000, bitrate: N/A
     Stream #0:0: Audio: pcm_s16le, 48000 Hz, 2 channels, s16, 1536 kb/s
 Output #0, mxf, to 'a.mxf':
   Metadata:
     encoder         : Lavf53.27.0
     Stream #0:0: Audio: pcm_s16le, 48000 Hz, 2 channels, s16, 1536 kb/s
 Stream mapping:
   Stream #0:0 -> #0:0 (pcm_s16le -> pcm_s16le)
 Press [q] to stop, [?] for help

 Program received signal SIGFPE, Arithmetic exception.
 0x0000000000a9ec0b in av_rescale_rnd (a=<optimized out>, b=0, c=0,
 rnd=<optimized out>) at libavutil/mathematics.c:91
 91                  return (a * b + r)/c;
 (gdb) bt
 #0  0x0000000000a9ec0b in av_rescale_rnd (a=<optimized out>, b=0, c=0,
 rnd=<optimized out>) at libavutil/mathematics.c:91
 #1  0x0000000000553acb in ff_interleave_new_audio_packet (flush=0,
 stream_index=0, pkt=0x7fffffffbfa0, s=<optimized out>)
     at libavformat/audiointerleave.c:87
 #2  ff_audio_rechunk_interleave (s=0x1425c80, out=0x7fffffffc050, pkt=0x0,
 flush=0,
     get_packet=0x502fd0 <mxf_interleave_get_packet>, compare_ts=0x502f60
 <mxf_compare_timestamps>)
     at libavformat/audiointerleave.c:132
 #3  0x0000000000543175 in interleave_packet (flush=0, in=0x7fffffffc300,
 out=0x7fffffffc050, s=<optimized out>)
     at libavformat/utils.c:3454
 #4  av_interleaved_write_frame (s=0x1425c80, pkt=0x7fffffffc300) at
 libavformat/utils.c:3477
 #5  0x00000000004466d5 in write_frame (s=0x1425c80, pkt=0x7fffffffc300,
 avctx=0x141e860, bsfc=0x0) at ffmpeg.c:833
 #6  0x0000000000448ec9 in do_audio_out (ist=0x141dd90, ost=0x1424830,
 s=0x1425c80, decoded_frame=<optimized out>)
     at ffmpeg.c:1072
 #7  transcode_audio (got_output=0x7fffffffc3c8, pkt=0x7fffffffc2a0,
 ist=0x141dd90) at ffmpeg.c:1838
 #8  output_packet (ist=<optimized out>, ost_table=0x1424830,
 nb_ostreams=<optimized out>, pkt=<optimized out>)
     at ffmpeg.c:2043
 #9  0x000000000044b72e in transcode (output_files=0x1424b00,
 nb_output_files=1, input_files=0x1424c10, nb_input_files=0)
     at ffmpeg.c:2804
 #10 0x00000000004432a2 in main (argc=<optimized out>, argv=0x7fffffffe698)
 at ffmpeg.c:4885
 (gdb)
 }}}

 The time base seems to be set only with when a video stream is specified,
 so trying to rescale it in case of audio only leads to a floating
 exception. The issue might also be reproducible with data or subtitles
 muxing without video.

-- 
Ticket URL: <https://ffmpeg.org/trac/ffmpeg/ticket/810>
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