[FFmpeg-user] concat issue

[Liam Condron-Farnos]

 >> To use the concat protocol, your files need to be one of a limited
number
>> of container formats, lkike mpeg ts. If they are MP4s, you have to create
>> intermediate .ts files in the way I described upthread.
>>
>> With the demuxer, you don't need to do that, it can take any input from
any
>> container, as long as they have the same resolution and codecs. So even
if
>> you want to concatenate an MP4 and an FLV files, you can do that, so long
>> as they both have h.264 video/AAC audio. Because the demuxer doesn't care
>> about the container format, there is no need to create those intermediate
>> .ts files, it can work straight from your initial MP4s.

>So in my case, I am starting with some videos (they could all be
>different codecs/containers).  I cut them up into  h.264/mp4,
>create some black silent videos of teh same codec/container.
>
>At the end I have a bunch of clips that are all h.264/mp4.  Is there
>any advantage in using the concat demuxer  as opposed to the
>concat filter?

*If* you put them into .ts files in the first place, rather than MP4s, then
no, there is no advantage to using the demuxer - in fact, I've found that
the protocol uses less resources (but only so long as your input files are
in one of those container formats that support file-level concatenation).
You will have to use `-bsf:a aac_adtstoasc` in your ocmmand-line, though.