I have been fooling around with screen capture for awhile now and I managed to capture the entire screen, certain areas on the screen etc...
But when I go into a game and try to capture the screen, it completely ignores the game and instead, captures the desktop (or whatever is behind the game window).
Another interesting fact is that the same thing happens with the PrtScn button.
Any ideas on how to capture a game's screen?
The screen capturing technique you are using works well for capturing things that aren't hardware accelerated. I suspect you'd have the same problem trying to capture a movie frame in Windows Media Player.
The solution is the do a screen capture from the hardware itself using DirectX. This article explains how to do that with some code and a managed wrapper around DirectX called SlimDX.
EDIT
If Slim DX doesn't work for you, then you'd just have to find another managed wrapper around Direct X. I don't think you are going to be able to do the screen capture without working at the hardware level, and DirectX is the means of doing that on the Windows platform.
Related
I was looking for examples of how to make a screenshot of an inactive window, but I did not find it. I want to take a screenshot of the game that works in the window, and not in full screen mode.
Which can be blocked by other windows.
I found some examples on the Internet, but could not implement in my project.
Could you set an example of how to do this with the help of EasyHook and SharpDX (or SlimDX) on language C#?
I'll be very grateful!
I created an example project for this on GitHub, https://github.com/spazzarama/Direct3DHook
Allows screen capture and drawing an overlay into the Direct3D target application using C#, EasyHook and SharpDX.
Keep in mind that some games will employ anti-injection/hooking techniqiues that may block EasyHook.
In addition this usually won’t work for minimised applications as it is best practice to pause your render loop when minimised.
I have problem with handling multiple video windows in directshow.
I have app in c# that captures video stream of my webcam and sends it through infinite pin tree to 2 separate renderers. When I run the app each of the renderers gets its own VideoWindow. Now when I set VideoWindow Style I can see changes only on one of them (looks like it is 2nd renderer window). Secound window is not effected at all. What should I do to access both of them? There is only one graph to build entire thing. Is there a way to reference videowindow by the renderer not by the graph? I was looking around web but there is nothing thats was able to point me in to good direction.
I am working on a multi-touch app using Monogame, where multiple users can work on a larger multi-touch screen with separate documents/images/videos simultaneously, and I was wondering if it's possible to make gestures "context-aware", i.e. two fingers pinching a document on one side of the wall shouldn't affect somebody panning the other side of the wall.
The way Monogame works is, all input points are translated into gestures, which can be read using:
if (TouchPanel.IsGestureAvailable)
{
var gesture = TouchPanel.ReadGesture();
// do stuff
}
Is there a way to make gestures limited to a certain point on the screen, or do I need to implement this myself? For example, by looking at the source code, it appears that the TouchPanelState class does all the work, but unfortunately its constructors are internal.
That feature is not built in to MonoGame, as it is not part of original XNA. Essentially you'd want more than one 'logical' TouchPanel defined by its sub-rectangle of the window. However TouchPanel is static, hence there is only one for the whole game in default XNA.
The good news is that MonoGame does its own gesture recognition. So, the code is there, you just need to make some changes to MonoGame.
Eg...
-Make TouchPanel a non-static class that can be allocated with a given subrect.
-Add non-static versions of all TouchPanel methods.
-The static methods redirect to a singleton/instance of TouchPanel, preserving the old API.
...now you can optionally allocate more TouchPanel(s) that AREN'T the whole screen.
Note: This doesn't help you, but MonoGame does allow you to have more than one OS window (on windows only afaik) in which case the static TouchPanel is the first window and there is a separate API for accessing touch input / gestures for any additional windows.
I have a question that How to detect the change on the screen? Its position is not necessary but is possible to get its position it will be helpful. I searched it on the internet but not found any suitable answer. Now, I am making a program in C# and I have to detect a change on the screen. I tried to capture four screen shots per second and compare them. This method works but it badly effect on the performance of the PC.
I think it is easy to do in C or Assembly language (x86) because in assembly we can get access to video memory directly.
Is it possible to do in C#?
Code sample will be appreciated.
Project: Detect any change on full Screen camera monitoring software.
Are you really looking just for simple difference of what you see on your monitor? I doubt that would do the job.
For motion detection from cam input you can take a look at Motion Detection Algorithms article on CodeProject.
Aside from taking screen captures and comparing them at some time intervals (which would cause performance issues),
The only solution i can think of is hooking up to system events, the "redraw" kind of events.
You will need to choose which events to hook your program with.
This codeproject tutorial might help-
http://www.codeproject.com/KB/system/WilsonSystemGlobalHooks.aspx
Hello,
I've written a program in C# to take screenshots of rectangular areas on my screen. however i don't seem to be able to capture the information from Adobe AIR applications. Instead, the applications beneath are what i end up with.
the meat of the action revolves around System.Drawing.Graphics.CopyFromScreen - passing in what amounts to an upper left point and a size and grabbing that area. I've had no problems so far with anything else, including flash movies in web pages.
I really have no idea where to look, and my google searches lead me to believe i'm the only person who has ever encountered this. :O
Any ideas?
Use the print screen key to take a screenshot of an Adobe AIR application on the Windows clipboard. Paste the screenshot into MS Paint. If you don't see Adobe AIR in your screenshot, then it's an acceleration issue - Adobe AIR is using a hardware accelerated surface (i.e. DirectX or OpenGL) for all its rendering, which means it just doesn't exist in the software screen buffer (there are ways to take screenshots of accelerated surfaces in other applications, but that gets very specialized).
This doesn't help you but I just threw together a quick WinForms app to try it and I was able to take a screenshot of TweetDeck using the CopyFromScreen function.