[FFmpeg-user] Floating point exception with flashsv2

[Jaume Lopez]

Hello,

I'm getting a "floating point exception" when trying to generate a small
flv file using flashsv2. At the end of the mail you can find the complete
output.

I've noticed that using the libx264 codec for the same settings work, and
using the flashsv2 codec for other sizes seems to work. Some examples I've
tested (only changing the -s parameter, the rest just the same):


320x180 --> Exception

400x225 --> OK
330x186 --> Exception

 300x168 --> Exception
380x214 --> OK

360x202 --> OK

100x56 --> Exception

340x192 --> OK

336x189 --> Exception
338x190 --> Exception


So it seems to happen to any size below 340. The format of the input file
doesn't seem to have any impact on this (I tested this with different files
in different formats, not just the same file converted).

Google didn't throw any useful tip on what could I be doing wrong. Thanks
for the help!


 ffmpeg -y -i input.mp4 -acodec aac -ar 44100 -b:a 128000 -b:v 512000 -f
flv -r 25 -s 320x180 -strict experimental -vcodec flashsv2 -f flv
output.flv
ffmpeg version 0.10.2 Copyright (c) 2000-2012 the FFmpeg developers
  built on Apr 25 2012 10:56:47 with gcc 4.4.5
  configuration: --enable-version3 --enable-libvpx --enable-libfaac
--enable-libmp3lame --enable-libtheora --enable-libvorbis --enable-libx264
--enable-shared --enable-gpl --enable-postproc --enable-nonfree
--enable-avfilter --extra-cflags=-fPIC --enable-librtmp
--enable-libopencore-amrnb --enable-libopencore-amrwb --disable-pthreads
  libavutil      51. 35.100 / 51. 35.100
  libavcodec     53. 61.100 / 53. 61.100
  libavformat    53. 32.100 / 53. 32.100
  libavdevice    53.  4.100 / 53.  4.100
  libavfilter     2. 61.100 /  2. 61.100
  libswscale      2.  1.100 /  2.  1.100
  libswresample   0.  6.100 /  0.  6.100
  libpostproc    52.  0.100 / 52.  0.100
[h264 @ 0x24a5300] Warning: not compiled with thread support, using thread
emulation
[aac @ 0x24a6500] Warning: not compiled with thread support, using thread
emulation
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'input.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: mp42mp41
    creation_time   : 2012-06-27 07:29:10
  Duration: 00:00:28.65, start: 0.000000, bitrate: 1209 kb/s
    Stream #0:0(eng): Video: h264 (Main) (avc1 / 0x31637661), yuv420p,
1280x720 [SAR 1:1 DAR 16:9], 948 kb/s, 25 fps, 25 tbr, 25k tbn, 50 tbc
    Metadata:
      creation_time   : 2012-06-27 07:29:10
      handler_name    : Mainconcept MP4 Video Media Handler
    Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo,
s16, 253 kb/s
    Metadata:
      creation_time   : 2012-06-27 07:29:10
      handler_name    : Mainconcept MP4 Sound Media Handler
Incompatible pixel format 'yuv420p' for codec 'flashsv2', auto-selecting
format 'bgr24'
[buffer @ 0x24ba9a0] w:1280 h:720 pixfmt:yuv420p tb:1/1000000 sar:1/1
sws_param:
[scale @ 0x256e4e0] w:1280 h:720 fmt:yuv420p -> w:320 h:180 fmt:bgr24
flags:0x4
Incompatible sample format 's16' for codec 'aac', auto-selecting format
'flt'
[flashsv2 @ 0x24c9f20] Warning: not compiled with thread support, using
thread emulation
Excepción de coma flotante


(Excepción de coma flotante = Floating point exception, I use Spanish
locale)