[Ffmpeg-user] Cutting 3gp files

[Benoit Fouet]

Bill Eldridge wrote:
> Benoit Fouet wrote:
>   
>> Bill Eldridge wrote:
>>   
>>     
>>> I'm trying to cut a 2-pass 3gp file (created in ffmpeg - both h263 & 
>>> mpeg4, AMR_nb audio) into 3 pieces -
>>>
>>> I try:
>>>
>>> ffmpeg -i bigfile.3gp -ss 0 -t 300 -vcodec copy -acodec copy cut1.3gp
>>> ffmpeg -i bigfile.3gp -ss 300 -t 300 -vcodec copy -acodec copy cut2.3gp
>>> ffmpeg -i bigfile.3gp -ss 600 -t 300 -vcodec copy -acodec copy cut3.3gp
>>>
>>>   
>>>     
>>>       
>> you should try with -ss an -t options before your input file
>>   
>>     
> Changes nothing - the size & times came out right before, the video 
> jumpiness is still there.
>   

ok

>>   
>>     
>>> And get unplayable , very different videos (out without the sound,
>>> and the error message:
>>>
>>>     [3gp @ 0x800fa0]fatal error, input is not a single packet, inplement
>>>     a AVParser for it
>>>
>>>   
>>>     
>>>       
>> or follow this message if the latter does not help ;)
>>   
>>     
> Well, if every video package required users to write their own AVParser 
> to simply
> split a video into 3 equal length pieces, life would have stopped long ago.
>
> However, reading back through the list, it does seem that giving a video 
> bitrate
> makes the files come out smoother. Still, -acodec copy gives the error 
> above -
> I don't understand why.
>   

neither do we, as you didn't even give the full uncut output from ffmpeg
command...
have you already tried re encoding both audio and video tracks ?

-- 
Ben
Purple Labs S.A.
www.purplelabs.com