Is there any Windows-based media player software that allows you to pause a video, and then un-pause a few seconds earlier?
I suggest a player agnostic solution: Install: AutoHotkey (freeware)
Example for Windows Media Player Define Space to be a macro for Ctrl+P and ←
;AutoHotkey Pause + Left Macro Example
Space::
Send ^p{Left}
To use it, enable the macro and set the focus (= click once) on Media Player's time scrollbar. This way while playing something you press Space and it pauses and goes back a few seconds. To continue press Space again and it continues and goes back a few more seconds.
Warning: Don't forget to disable the macro when not using that feature or it will drive you nuts ;)
AutoHotkey has a powerful macro language. If you can do a little programming you may even build something like a simplified remote control for your player by changing window focus and such things.
You can do it with VLC.
Combinations of CTRL, SHIFT, ALT and Left arrow will jump backwards - replace with right arrow to jump forwards.
If you look in the VLC preferences window, under hotkeys, you can see which key-combination does which jump.
If you are an advanced user (or know someone) and your computer has a microphone, then you might be able to use Windows Speech Recognition Macros :
The Windows Speech Recognition Macros tool or WSR Macros for short extends the usefulness of the speech recognition capabilities in Windows Vista.
Users can create powerful macros that are triggered by spoken commands which can perform a series of tasks from as simple as inserting your mailing address to as complex as providing a completely different speech interaction with applications.
Please note that most Bluetooth microphones do not function well with Windows Speech Recognition due to limited audio bandwidth.
So in theory, by using nothing else than one's voice, one should be able to program a speech-activated macro that will send keyboard commands to the player to pause, rewind and unpause. Most players support a keyboard interface.
The download is available from here, some archived macros are available here, and a forum here.
From the large availability of related material on the Internet, I would say that the technology does work. However, I have never tried it, so cannot testify for its efficiency.
Daum PotPlayer, or The KMPlayer. Both can do this. Just hit the left arrow key to jump back(5 seconds is default but you can change this.) http://filehippo.com/download_kmplayer/ You can search around for the PotPlayer.