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Detect any video playing on Windows OS (7,8,10)

I am search for a way to detect if video is playing on Windows OS (7,8,10).
SetThreadExecutionState api function does not help I have tryied with different players (VLC, BS player etc.) but it seems they don't use flag ES_DISPLAY_REQUIRED.
Checking for disabled screensaver is not good solution, because it should be allowed at first place and almost nobody use screensavers nowdays.
My app is a break timer, I am using LASTINPUTINFO() function but I want to know
when the user is watching video because there is not input (keyboard or mouse) during this time.
A dirty and partial solution would be if the app does snapshot of region in the center of the screen and comparing hashes, but it will be 90% accurate.
Any better ideas?

Dynamically increasing/decreasing speed of a video in a windows forms application

I'm building a Windows Forms application in VS 2010 that smoothly increases or decreases the speed of a video playing back based on the speed of the user input.
I've tried several avenues..
1.) Using the AudioVideoPlayback DirectX class - I set the speed of the video, by setting the current position of the video, based on a timer.. and increased or decreased that value based on user input. While this worked on my PC, it lags a lot on our lower end target PC's. Can anyone think of a more efficient way to increase/decrease the speed of playback using this class?
2.) I've tried the Windows Media Player ActiveX control, and tried setting the rate/position dynamically, but this is extremely jumpy and laggy even on my development PC
3.) I've tried the Apple QuickTime Control 2.0 COM Component that comes with VS 2010, and it's also very laggy.
4.) I'm trying to figure out how to set the speed on the Shockwave Flash Object control, but haven't found that out yet
Can anyone suggest other avenues to explore? I just need to be able to increase/decrease the speed of video playback smoothly based on user input without lag. I don't care what format the video needs to be in, all videos can be converted to the required format.
Any help/ideas will be appreciated.
Thanks

The ultimate way is to decode the Bitmaps from videos, and handle the frames yourself.
Try the CaptureNET example from DirectShow.NET. It allows you to capture bitmaps from each frame. After that, write your own playback control to handle the refresh rate.

After trying many different formats/libraries and components I found the VLC Media Player ActiveX control to be the most efficient method to slow down/speed up video without any noticeable lag.

Reading specific frames from video file with .NET (not necessarily in sequential order)

I have a .NET Winform application and i need to show specific frames of a video file. Frames aren't necessarily in sequential order and are loaded when the user moves a slider, or when the application fires some events. I tried the following things:
Using EmguCV (OpenCV Wrapper): The problem here is that when i use SetCaptureProperty (With CAP_PROP.CV_CAP_PROP_POS_FRAMES, AVI_RATIO or MSEC ) to sets capture's position, the position isn't seted correctly (I checked it using GetCaptureProperty next to the SetCaptureProperty instruction). So, the frame returned by QueryFrame isn't the needed frame.
Using WPF MediaElement with Clock driven behavior: I can set the position of the video at the place that i need. The problem is that i don't know how get only one frame of the video sequence. By default, i have the Clock controller paused. When I set the position, If I call Clock.Controller.Resume(), then the video start playing from here. If I don't call Clock.Controller.Resume(), or if i call Clock.Controller.Resume() and then Clock.Controller.Pause() nothing is happening.
Im looking for another video library that can be used for accomplish this work, but i am not sure about what could be used. Any idea?
Thanks a lot for all comunity members, not only for help with this answer, but for the very big help that you give me with my problems every day. Iam new, but i would try to return these helping others with your problems.
Sorry for my terrible english! (Im spanish speaker and english speaking is not my best quality :S)

Creating a Windows Game Overlay Application?

After playing quite a bit of Bad Company 2 over the last month, I'm getting kind of tired of Alt+Tabbing out of my game to change the song on iTunes. I've got a fairly good iTunes controller library already built for a previous project I was working on, and I'd like to create a WPF application mimicking the BC2 UI that would overlay the game when pressing a shortcut key, much the same way as the Steam Community overlay.
The only problem I foresee is getting my application to overlay BC2 when the user presses a specified shortcut key in-game. Is there a way to intercept a keypress from BC2 (or, really, any Win32 application) and use it to bring my app to the foreground?

In order to have a global keyboard shortcut, you need to use a Hook.
Here is a tutorial showing how to do Keyboard Hooks in C#.
That being said, doing the overlay may be difficult, depending on how the game is written. Many full screen games cannot (easily) have other programs run in front of them. I'd play with making sure that works correctly in your specific game first.

polling joystick C#

i have an application that records a date/time when the space bar is pressed
unfortunately, the window doesn't always have focus, for various reasons. eg virus checker popup, itunes update, windows update, etc
so what i though would be a cool idea is to use a joystick button, then regardless of which window has focus, i can always detect the button press event and record the date/time it was pressed.
now i had a look at a few game tutorials, but they seem to have the joystick polling tied into the screen refresh event, because in a game i guess if the computer is slow and the screen doesn't refresh often, having the joystick button pressed is going to make no difference anyway.
That doesn't really suit my need, so i am looking at running a thread that will poll the joystick every so often
My questions are
is a background thread the best solution
how often should i poll the joystick
what kind of timer should i use to determine the polling frequency.
I would like the responses to be at least equivalent to a keyboard. also need to make sure it doesn't auto-repeat if trigger is held down.
any sample code (C#) appreciated
thanks
alex

If you want to go for polling the joystick just because you are not able to capture the keyboard event, I think you need to re-work your strategy.
Even if your form doesn't have the focus there are ways that you can make sure you know of the keyboard state.
You could set up a system wide keyboard hook which can be done in C# using the SetWindowsHookEx API call.
This is delving a little in unmanaged code and Windows API, but I think it's a better idea than polling a joystick cause you won't need to add a joystick to your computer just because you need to capture datetime at the press of a spacebar.
Do a little search on google for keyboard hooks in C#. It's easier than many people believe.
I don't think using a timer object to do this is a good idea at all. Cause I believe you said you need to do it at the press of a key.

Your best bet would be to create a Timer object on your form, and tie the joystick check to the Tick event.
I've also found that running simple stuff like this every 100ms (10 times a second) has a negligible effect on CPU usage.

Use something like AHK (Auto HotKey) it is a simple language that can be compiled to an EXE and is designed for automating the keyboard and mouse, I'm not 100% sure how well it works with a joystick, but I'm sure it's possible they managed to write some stuff for the wii remotes.
Also the IRC Channel and Forums always have people willing to help if need be.