[FFmpeg-user] 2 pass seg faults if audio codec not specified in pass 1

Sean Darcy seandarcy2 at gmail.com
Sun Jun 15 17:01:57 CEST 2014


On 06/15/2014 10:52 AM, Carl Eugen Hoyos wrote:
> Sean Darcy <seandarcy2 <at> gmail.com> writes:
>
>>> If the segfault gets fixed, you get an output file but
>>> no indication that it is broken
>
> This seems wrong, x264 prints a message at the end that
> the number of frames did not match between first and
> second pass.
> I fear that most users will ignore this messages (that
> indicates a completely broken two-pass encode) though.
>
> This is discussed in ticket #2846 but it is not easy
> to read there.
>
>> ffmpeg -y -i input -c:v libx264 -preset medium -b:v 555k
>> -pass 1 -an -f mp4 /dev/null
>
>> ffmpeg -y -i input -c:v libx264 -preset medium -b:v 555k
>> -pass 1 -c:a libfdk_aac -b:a 128k -f mp4 /dev/null
>
> This looks better, you can check if the passlog files
> are different to confirm my suspicion.
>
> Carl Eugen
>

OK. I'll make the change.

sean



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