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

Sean Darcy seandarcy2 at gmail.com
Sun Jun 15 21:42:00 CEST 2014


On 06/15/2014 11:01 AM, Sean Darcy wrote:
> 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

Done.

sean



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