Gfilui

kdenlive is (in my experience) the easiest software which will allow you to perform that task in a few steps and without problems. Even so, the OpenShot Video Editor project is also useful but it yet needs lots of hard work to get closer to the kdenlive.

Here are a screenshot of the kdenlive and openshot respectively:

Good luck!

With new version from ubuntu avconv

avconv -i srcFileName -c:a copy -c:v copy -ss 00:03:40 -t 00:01:12 targetFileName

• First argument time is from time


• Second argument is duration (not end time) duration may be either in seconds or in "hh:mm:ss[.xxx]" form.

Please refer to ffmpeg documentation for more informations

I like kdenlive for finishing up as well or clipping out small chunks...but if he wants to split a LARGE lecture into smaller pieces he could try:

ffmpeg -i input.mpg -ss 00:00:10 -t 00:00:30 out1.mpg -ss 00:00:35 -t 00:00:30 out2.mpg

discussion of the command is here: http://ubuntuforums.org/showthread.php?t=480343

OpenShot Video Editor looks promising. Have you checked it?. Checkout the features: http://www.openshot.org/features/

To install it just open a terminal and run the following commands:

sudo add-apt-repository ppa:jonoomph/openshot-edge
sudo apt-get update
sudo apt-get install openshot openshot-doc

Just give a try.

My preference for easy video clipping has always been avidemux.

Just set the video and audio encoding to Copy and choose the container format you want, within reason.

Try Avidemux

sudo apt-get install avidemux

or LiVES

sudo apt-get install lives

more
here http://techcityinc.com/2009/02/04/top-10-free-video-editors-for-ubuntu-linux/ (Dead link, redirects to random commercial sites)

I use Kdenlive, but I wouldn't be surprised if you could even slice video this way in PiTiVi:

1. Create a new project with your full lecture.


2. Set your start and end points for the first "manageable chunk" in the clip monitor.


3. Drag from the video in the clip monitor down to your timeline. It will be just the chunk you chose.


4. Set new start and end points in the clip monitor and repeat as needed.

For cutting, merging, scaling etc one can use … Blender (yes, this 3D editor, but it has also video editing part). You need workout some 20-min tutorial to survive the interface, but then it appears to be unexpectedly pleasant to use.

I'm using ffmpeg CLI interface for that. It's very easy and fast:

• 
  

  to cut video:

  
  
  

  ffmpeg -i InputFile -vcodec copy -acodec copy -ss 00:00:00 -t 00:01:32 OutPutFile
  

  
  


• 
  

  to cut audio:

  
  
  

  ffmpeg -i InputFile -vn -acodec copy -ss 00:00:00 -t 00:01:32 OutPutFile
  

  
  

In both of these -ss is the start point, while -t is the duration of the piece.

You can calculate duration e.g. using LibreOffice Calc or python's dateutil package.

There is also WinFF that is avconv graphic interface. It works great. I installed it from Ubuntu Software Center.

Here is the screenshot:

In PiTiVi 0.13.5 (Ubuntu 10.10) I was able to simply select a clip and go to Timeline > Split (or just press "S").

For quickly cutting I have used MythTV. I recorded some show, let it automatically search for the commercial breaks and fine-tuned the found markers. After this I started the Myth archiving function and burned all to DVD, without the commercials.

I have to admit, it worked gread from about 2006 or such. Somewhere in 2008 or 2009 some update ruined it all, my markers where somehow shifted.

Right now, I'm in the progress of re-installing this myth stuff, just to see if I can get the trimmer/editor and archiver working.

I am running into the same trouble.
I have searched and tried to install this sort of ubuntu software
for many times, but unable to install any of them!
Perhaps my repository is broken?

It always says this depends that,
this depends A but B is going to be installed

Yesterday I just found that I can do it online,
With a youtube account:) If you are in a hurry, and do not have
enough time to try which ubuntu software works for you,
then do it online.

Go to youtube account, upload your video, then
select
Video Manager,
there is a Enhancement option,
at the bottom right corner there lies Trim option

Watch this 1 minute tutorial if you still can not find it

vidcutter is a very useful tool for cutting, trimming and merging videos in ubuntu:

Install vidcutter:

sudo add-apt-repository ppa:ozmartian/apps
sudo apt update
sudo apt install vidcutter

works in ubuntu 17.10

Pitivi too complex? Well... I suggest you learn how to use the mouse then lol

Anyway, I always use Kdenlive.
Just import the video, drag it onto the timeline, click on the spot where you want to split it, right-click it, and choose cut. Then remove the part you don't need.

If you want a GUI application you can use dmMediaConverter, a ffmpeg frontend, which has a split function, without reencoding, fast. Just add the split points and press Run. Also, it can do a lot of other stuff.
http://dmsimpleapps.blogspot.ro/2014/04/dmmediaconverter.html

I've struggled with this same issue, having a large video file that I want to cut and save as separate scenes. After trying to do this in the usual suspects all listed by others here I ended up using Kino.

You will have to import the file as Kino needs it in dv format (whatever that is) and you can then specify start and end point for each clip on the Edit tab, then export each clip individually on the Export tab. Works great and is fast, the slowest part is the initial import of the video file. You can even add effects like titles to each clip.

I found that it is hard to find the exact spot to cut the scene in Kino and when I play the vid in the built in player there is no sound (there is when exported) and it plays too fast so I play the video in avidemux, find the time or frame number where I want to cut it, then use this info in Kino.

I do find it crashes a fair bit (I use Ubuntu 15.04 Kino v1.3.4) but it will recover where you were upon restart.

Update on the Kino webpage:

Kino is a dead project

( 05.08.2013 14:15 )

Kino has not been actively maintained since 2009. We encourage you to try other Linux video editors such as Shotcut, Kdenlive, Flowblade, OpenShot, PiTiVi, LiVES, and LightWorks.