[FFmpeg-user] [AVCHD] Join + resize?

[Carl Eugen Hoyos]

Gilles <codecomplete <at> free.fr> writes:

> On Wed, 31 Oct 2012 00:02:16 +0000 (UTC), Carl Eugen Hoyos
> <cehoyos <at> ag.or.at> wrote:
> 
> >Gilles <codecomplete <at> free.fr> writes:
> >
> >> 1. Join two files (40mn + 10mn; video = MPEG-4 AVC 
> >> 1440x1080, 50fps; audio = A52 AC3 48KHz 3F2R/LFE)
> >
> >Does concatenation (with `cat`) work?
> 
> Not on Windows

$ copy /b input1 + input2 + input3 output
or
$ copy /b input* output

> I'm trying to first convert the two files into
> something smaller, before editing/joigning them 

I still suspect (the same discussion currently happens 
in another thread with a similar name) that 
concatenating the files would allow you to work on 
perfectly synchronised and complete files (assuming 
there are no intended cuts between the files) while 
re-encoding first imo means that you will have a 
discontinuity.

> with eg. AviDemux or some other NLE editor.
> 
> Is there a codec that would give a less compressed output than mpeg4?

less compressed?

> ffmpeg -i myfile.mts -s 640x480 -codec:v mpeg4 -profile:v 3 
> -codec:a copy myfile.mp4

Do you know what -profile:v 3 does in this line?
(I ask because I don't know.)

Without you specifying a bitrate or a constant quantiser, 
this is not going to produce something useful.

Carl Eugen