Smart-Copy

[AQUAR]

@ Papou

Aren't all operations used here supposed to work?

That would be the aim of a work in progress, and should be the case of a final.

In principle, the only possible gotcha is selecting a compatible encoding.

In practice there is more trickery involved, as you found out.
To get at that trickery, you need to know the ins and outs of all the dependancies involved.
Way beyond me, so I bow to the expert opinion of the person here in the know - Mean the developer.
And Mr Mean says its too difficult.

That still leaves You with a desire for AVC smartcopy in Avidemux, just like the rest of us (me included).
Some options now are:
1) Accept that some implementation of a smart copy is not likely to be forthcoming from mean.
2) Dig into the principles of operation and back up that new knowledge with some smartcopy code for avidemux.
    There are many such type of contributions from members, as avidemux is open source.
3) Find a work around fiddle, like you tried with cut - recode - append. Personally, I applaud and appreciate such shared initiative.
4) Find an editor that has smartcopy on AVC. etc

Here is a variation on your intiative.
And one you must take with a pinch of salt because I also am just a Noob.
Say that section 2 is what you want to cut out of your video, except for some frames at the start and some frames at the end.
These frames of course would be inside a GOP and are therefore not Idr frames.
Now save a few GOPS from the start and end of the cut and compatibly recode them ALL as Idr frames
(ie create a segment 2A and a segment 2B all with Idr frames)
Now edit/cut those segment for the wanted frames leaving 2a and 2b (still all Idr frames).
Then append 1 plus 2a plus 2b plus 3 and see if that avoids strange frames at the intended cut points.

[Papou]

@ Papou

Aren't all operations used here supposed to work?

That would be the aim of a work in progress, and should be the case of a final.

In principle, the only possible gotcha is selecting a compatible encoding.

In practice there is more trickery involved, as you found out.
To get at that trickery, you need to know the ins and outs of all the dependancies involved.
Way beyond me, so I bow to the expert opinion of the person here in the know - Mean the developer.
And Mr Mean says its too difficult.

Your explanation why the very simple, common appending of videos with like characteristics (Mpeg4 AVC (x264)  30 fps same size) does not work is very very, very, unclear.

[AQUAR]

Your explanation why the very simple, common appending of videos with like characteristics (Mpeg4 AVC (x264)  30 fps same size) does not work is very very, very, unclear.

Of course as I didn't explain it AT ALL.  And neither did I say appending doesn't work.
I can't help it if people mistake a beta program as a final/proven program. 

Smartcopy is the topic here not the append function.
So what I did do was reference your own initiative for a "smart copy" like process.
I added some info for you to try out if you wished too (don't expect others to do it for you).
And I qualified that info with "take it with a pinch of salt".

I have some comprehension of why the smartcopy process is difficult to implement.
Not going to elaborate on that, as that comprehension is at Noob level.

If you reject the responses already given, try turning the pages of the book yourself.

[lenildosb]

hi friend @Papou, use the version Avidemux 2.4 GTK+, it has the function Smart-Copy!!!

[AQUAR]

Everyone - don't take any notice of this response from lenildosb.

Avidemux 2.4 is designed to work with older codecs and so is not for AVC.